CONTRACT N°: FIR1-CT-2002-2011 ACTINET - cordis.europa.eu fileACTINET Final Technical Report...

FINAL TECHNICAL REPORT

CONTRACT N°: FIR1-CT-2002-2011 PROJECT N° : ACRONYM: ACTINET TITLE: ESTABLISHMENT OF A NETWORK OF EXCELLENCE FOR ACTINIDE SCIENCES PROJECT CO-ORDINATOR:

Forschungszentrum Karlsruhe GmbH (FZK) DE

CONTRACTORS: Commissariat á l'Energie Atomique (CEA) FR

Institute for Transuranic Elements, JRC (ITU) DE

MEMBERS: Paul Scherrer Institut (PSI) CH

University of Manchester (UniMan) UK

Forschungszentrum Rossendorf e.V. (FZR) DE

Ecole Nationale Supérieure des Mines de Nantes (ENSTIMN SUB): FR

Association pour la Recherche et le Développement

des méthodes et Processus Industiels (ARMINES SUB): FR

REPORTING PERIOD: FROM 01.11.2002 TO 31.10.2004 PROJECT START DATE: 01.11.2002 DURATION: 2 years Date of issue of this report: 20.05.2005

Project funded by the European Community under the ‘EURATOM’ Programme (1998-2002)

ACTINET Final Technical Report 20.05.2005

Table of contents 1 Executive summary 3 2 Detailed Final Report 4 2.1 Objectives and strategic aspects 4 2.2. Scientific and technical description of the results 5

WP. 1: Assessment and proposal of a management structure and a "pool” system of facilities 5 WP. 2: Selection of research areas subjects of broad interest 9 WP. 3: Organization of education and training system 11 WP. 4: Management and dissemination of research activities and results 11

3 Perspectives for ACTINET 13

3.1 Progression of ACTINET-5 to ACTINET-6 13 3.2 Progress in research undertaking 13 3.3 How to sustain ACTINET as a long-term association 14 3.4 Elevation of the innovative research projects 14 3.5 Expansion of international cooperation 14

ANNEXES 16

ANNEX I: Assessment of key issues in Scientific Scope and Task Cornerstones A 1 ANNEX II: Assessment of Information on Research areas,

Scientific interest, “Pooling” Research facilities, Education and Training, Dissemination of Knowledge. A 3

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ACTINET Final Technical Report 20.05.2005

1. Executive Summary The project “ACTINET” was to establish a network of excellence for actinide sciences in Europe to sustain and disseminate the indispensable knowledge and to advance the innovative research activity in actinide sciences. In the sphere of this network it was also envisaged to build up competent actinide scientists of the future generation by promoting the research collaboration via mobility of young scien-tists within the network member laboratories.

For establishing the network, the meetings have been organized by the core-institutions (FZK-INE, CEA-DSOE, JRC-ITU) for information exchange as well as for assessment of common interests on inviting the representatives of various laboratories working with actinides within the EU countries. Two workshops of broad participation (28 laboratories) were held for this purpose along with numer-ous internal coordination meetings among the core-institutions.

From the workshops together with the internal coordination meetings, a conceptual consensus has been attained for the scientific scope and task cornerstones of the “ACTINET” programme. They are the following:

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ACTINET FINAL Technical Report 20.05.2005

Scientific Scope 1. Chemistry and physics of actinides in solution and solid phases 2. Chemistry of actinides in the geological environment 3. Chemistry and physics of actinide materials under irradiation

Task cornerstones

1. Coordination and common utilization of pooled facilities 2. Training and education in actinide sciences 3. Evaluation and dissemination of knowledge

The interests expressed by 28 individual participating laboratories to each scientific scope and task cornerstone are assessed and summarized as follows:

Scientific scope Task cornerstones 1. Scope: 25 laboratories 1. Cornerstone: 18 laboratories 2. Scope: 19 laboratories 2. Cornerstone: 24 laboratories 3. Scope: 9 laboratories 3. Cornerstone: 20 laboratories

Overall numbers suggest that a network of excellence for actinide sciences is an indispensable estab-lishment welcomed by nearly all-European nuclear science laboratories. At this stage the project is named “ACTINET-5” (5th Framework) which is to distinguish from the executing stage project that is then called “ACTINET-6” (6th Framework). The overall evaluation performed in “ACTINET-5” has been directly handed over to “ACTINET-6” for its fundamental concept and structure building.

On-going research activity, main scientific interest, available facilities and manpower of 28 laborato-ries in Europe, which have expressed their interest of joining the network of actinide sciences, have been evaluated and compiled in this report. They have become actually the members of ACTINET-6.

Establishing the network of excellence for actinide sciences in Europe, which was the main objective of ACTINET-5, has been successfully accomplished.


2 Detailed Final Report 2.1 Objectives and strategic aspects The advanced research on "Actinide Sciences” is a major part of the essential endeavours for the further development of nuclear fuel cycle, coupled directly with the safe disposal of nu-clear waste. For various reasons, the research activity in this subject area has been stagnated in the past in European countries. To sustain and disseminate the indispensable knowledge as well as to advance the research activity of actinide sciences in Europe, it was planned to build a Europe-wide networking for this particular research area. The network was envisaged not only to facilitate the coordination and utilization of "pooled” facilities for the research on ac-tinide sciences but also to consolidate and exploit the education and training possibilities in Europe. To prepare such a networking in the period of the 5th framework programme was the main objective of the present project. The structure of the “Network of Excellence for Actinide Sciences” was foreseen to comprise the core-institutions and associated laboratories. The three core-institutions, which conceived the network onset together, were envisaged to promote the practicable organisation of the network. The associated laboratory can be anyone having keen interest to carry out actinide research by joining the network. Nuclear science laboratories of universities and national laboratories in Europe can be associated members to join the individual subject areas of acti-nide research. The networking was anticipated to include those research subjects relevant immediately to the future development of nuclear waste disposal within the context of nuclear fuel cycle. The selected research areas were expected to comprise all aspects of basic understanding, which might well promote a better management of nuclear fuel cycle, leading to the sustained safety of waste disposal. Such a concept encompasses safe geologic disposal of nuclear waste, ex-tending also to an alternative approach, i.e. actinide partitioning and pertinent fuel develop-ment for transmutaion. In the preparatory stage to establish the “Network of Excellence for Actinide Sciences” within the 5th framework programme (ACTINET-5), the consolidation of scientific scope and task cornerstone was the intensive discussion among the core institutions and associated laborato-ries. The final scientific scope and priority research subjects were selected based on the broad common interests addressed by all future members and hence approved to implement them in in the executing stage of the network, which was programmed as actually operational within the 6th framework programme (ACTINET-6). They advocate the strategic guidelines of the network. Scientific Scope

1. Chemistry and physics of actinides in solution and solid phases 2. Chemistry of actinides in the geological environment 3. Chemistry and physics of actinide materials under irradiation

Task cornerstones

1. Coordination and common utilization of pooled facilities 2. Training and education in actinide sciences 3. Evaluation and dissemination of knowledge

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For promoting the structural establishment of the network that adhered to the aforementioned scien-tific scope and task cornerstones, the working package shared by the core-institutions was prepared as follows:

WP. 1: Assessment and proposal of a management structure and a "pool” system of facilities (FZK-INE) WP. 2: Selection of research areas subjects of broad interest (JRC-ITU) WP. 3: Organization of education and training system (JRC-ITU) WP. 4: Management and dissemination of research activities and results (CEA-DSOE) WP. 5: Project management (FZK-INE) The primary strategy of “ACTINET-5” was to appraise the potentials of actinide research in Europe, individual areas of development and scientific subjects of future interest. The subse-quent strategy was how to coordinate and promote the research activities of common interest in actinide sciences in a sustainable system. 2.2 Scientific and technical assessment In the coordination meeting (21. 02. 2003) for the evaluation of the 1st workshop, it was agreed upon to maintain the acronym “ACTINET” also for the execution stage of the network project in the 6th framework programme. To distinguish the network projects in the 5th and 6th framework programmes, the acronyms were then denoted to “ACTINET-5” and “ACTINET-6”. In the context of the envisaged sustainable network, even after the termination of EC support, the acronym ACTINET shall be main-tained.

The achievements of ACTINET-5 are summarized in the following for each work-package separately (Details are put together in ANEXES and the management report).

WP 1: Assessment and proposal of a management structure and a “pool” system of fa-cilities Objectives Establishing a sustainable “Network of Excellence for Actinide Sciences” is a new feature, being definitely different from the former EC projects. The success of such a network de-pends largely on an efficient management and co-ordination. Therefore, the goal of this work-package is to develop a structure, which is capable of managing the network for a large num-ber of participating laboratories with different interests in actinide sciences. The second aspect of this work-package is the establishment of “pooled” facilities, which can be beneficial for all members of the network. Information has to be collected on the facilities and experimental methods available in the laboratories of the core-institutions and associated members, which are apposite for collective researches within the network. A detailed assess-ment of the “pooled” facilities is necessary for their availability and precincts. Besides techni-cal scrutiny, discussion is opened on general management issues and possible coordination of pooled facilities.

7


Description of work Various options were discussed and evaluated for the management structure of the network in the internal coordination meetings among the core-institutions as well as in the workshops of broad participation (28 laboratories). And how to coordinate a “pool” system of large and/or specific experimental facilities was the subject of intensive discussion as well. As for the management structure building, a case study example prepared by CEA-DSOE) was adopted after improving a number of details and the result was agreed on to implement in ACTINET-6. Preparatory discussion was concentrated on the following subjects: • Assessment and coordination of the millstones of the network management structure

• Availability and coordination of “pooled” research facilities for external partners

• Management of financial resources for a collective investment policy

Achievements

Submission of a common proposal for ACTINET within the 6th FP Within the ACTINET-5 activity, a general consensus was attained to promote ACTINET-6 as follows:

• CEA was selected as a coordinator to prepare and submit the ACTINET-6 proposal, • Core-institutions for ACTINET-6 were CEA-DSOE, JNC-ITU, FZK-INE and SCK-CEN, • The scientific scope, task cornerstones and management structure as addressed in

ACTINET-5 were accepted to implement in ACTINET-6 • The activity of ACTINET-5 should be maintained, even if the 5th and 6th FP activities

were overlapping, to find out the feasibility of maintaining the whole ACTINET activity as a long-term institution.

General management policy and structure of ACTINET For a successful implementation of the network, an efficient management structure was of cardinal importance. The management system was entitled to take the following into consid-eration:

* Consolidation of various interests and opinions of the network members

* Outline the general rules and guidelines for the execution of the network

• * Internal as well as external evaluation of the scientific performance

* Conflict solving and promoting the research performance at excellence

* Making efficient decision possible with a minimal administrative load

The organisational structure of the ACTINET-6 Consortium and the management structure prepared as a case study example by CEA-DSOE were consolidated in the core-institution meetings upon amending some details and adopted as fundamentals for the ACTINET forma-tion. The ACTINET organization is structured into four committees having the following functions:

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• Governing Board: Consisting of one representative from each member organisation. The main decision making body for the general policy and strategic orientation of the NOE.

• Executive Committee: Consisting of one member from each core group and equal num-ber of persons selected from associated members. Preparing and implementing decisions to be adopted by the governing board.

• Scientific Advisory Board: Up to 8 independent experts appointed by the governing board. Evaluating the scientific quality of the research performance.

• Management team: Day-to-day management of the network. The team headed by the coordinator consists of managing leaders of each scientific scope and task cornerstone.

Chair Person of the Governing BoardGoverning Board

- 1 representative per ACTINET member organisation

Head of the Executive CommitteeVice-Head of the Executive Committe

Executive Committee-8 persons proposed by the Head of the Executive Committee

(4 from the Core Group)

Coordinator

Chair Person of the Scientific Advisory CommitteeScientific Advisory Committee

- up to 8 persons serving in their personal capacities

Management Team

EC

Fig. 1 Organisation structure of ACTINET-6

This structural concept of the organization was adapted to ACTINET-6 (see Fig. 1)). Fur-thermore, the management structure of ACTINET-6 shown in Fig. 2 followed to a great ex-tent the recommendation of ACTINET-5 (it should be noted that the Working Groups 1-3 correspond to Scientific Scopes 1-3).

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- Financial Officer- Legal/IPR Expert

- Database Manager - Other as necessary

Working Group 2Chemistry of actinides in the

geological environment

Working Group 3Chemistry and physics of actinide materials under / after irradiation

Task Group 1Pooled Facilities

Task Group 2Education and Training

Task Group 3Use and Dissemination

Electronic Info infrastructure

Head of the Management Team(Coordinator’s representative)

- Assistant- Quality Management Assistant

Working Group 1Chemistry and physics of actinides

in solution and solid phases

Fig. 2 Management Structure of ACTINET-6

Consortium Agreement between the ACTINET-6 Participants At the 2nd ACTINET-5 workshop, held in Avignon in March 2003, the attending scientists were asked to express their interest to participate in the envisaged ACTINET-6 and to support a common proposal within the 6th EC framework programme in written form. The “memoran-dum of understanding” outlined by CEA and approved by the ACTINET-5 core institutions was intensively discussed at the workshop and finally approved by all involved. Based on this document, a consortium agreement among the ACTINET-6 participants was drafted by CEA and, after accommodating legal hurdles, finally signed by all ACTINET-6 partners in March 2004. The consortium agreement was a mandatory part of the EC-contract of ACTINET-6, which specifies the legal basis for the collaboration among the partners.

General discussion among the core institutions and also with the future ACTINET-6 partici-pants within ACTINET-5 was considered as essential for establishing a legal frame of ACTI-NET-6, since the main objective of ACTINET-5 was to establish such a network. Coordination and utilisation of “pooled facilities” (Task Cornerstone 1) Opening access to the nuclear facilities of the core institutions to the associated members was one of the essential task cornerstones of ACTINET. The utilization of pooled facilities was generally understood to make an intensive exchange of know-how possible and to enhance research collaboration among the network laboratories. This issue was discussed intensively between the core institutions and participants in the workshops. As a result, a detailed list of facilities was compiled, which were available from the core-institutions for a “pooled” sys-tem. The constellation of such a system is not only to provide facilities to handle radioactive materials but also to assist sophisticated experiments, such as using synchrotron radiation sources, laser spectroscopy, etc. For this purpose, the facilities from non-core members have been also included (e.g. FZR: ROBL at ESRF and laser spectroscopy; PSI: micro-XAS). Fur-thermore, it was discussed to establish a “Theoretical user lab” to disseminate expertise of computational actinide chemistry. The assessment of discussion within ACTINET-5 on the pooled facilities has been a straight assistance for preparing the ACTINET-6 project in detail.

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Another important aspect discussed among the core and associated members was under what conditions the access to the pooled facilities should be possible for external users. Some members preferred “user laboratories”, where guest could perform experiments independ-ently, while others intended to open their labs only in close scientific collaboration with ex-ternal partners. Finally it was agreed that the scientific priority and the resources required in any proposal should be reviewed and approved by the scientific advisory committee. A de-tailed procedure was elaborated and included in the ACTINET-6 management structure.

Among the ACTINET-5 participants, it was agreed that the general structure of the network should integrate the following: Core-institutions provide primarily the “pooled” facilities to carry out research on actinide materials. • Access to the “pooled” facilities is allowed for associated members with a keen interest in

actinide research. This concept of pooled facilities was incorporated within the ACTINET-6 proposal and is presently implemented. Besides the ACTINET-6 core institutions, pooled facilities will be provided by FZR (active beam-line ROBL at ESRF and laser spectroscopy) and PSI (active micro-XAFS-beam-line at SLS).

WP 2: Selection of research subjects of broad interest

Objectives

A survey of general and specific interests of actinide scientists in Europe was the primary ob-jective to orient the ACTINET activity as a whole. Accommodation of various interests to common nominators and hence the selection of research subjects of broad interest was the subsequent objective for structuring the ACTINET project. Description of work Discussion was conducted in the workshops on inviting the representatives of actinide re-search laboratories in Europe (28 laboratories) to formulate scientific scope that covers prop-erly the various interests of all participants. After reaching common agreement on the scien-tific scope, the subject-wise interests of individual participants were comprehensively dis-cussed in the workshops and the outcomes were implemented into each relevant scope. Participants of the first workshop were called for summarizing their specific scientific inter-ests in actinide sciences. All responses were compiled and distributed at the second ACTI-NET-5 workshop, held at Avignon, March 6/7, 2003. This compilation served as a basis for the joint programme of research that was imbedded later in the ACTINET-6 project. All par-ticipants in ACTINET-5 have become thereafter members of ACTINET-6.

At the first workshop held at FZK, Karlsruhe, on Dec. 11/12, 2002, a questionnaire was ad-dressed to the participants regarding their scientific interests. As reflected by the numbers of laboratories (28 different institutions), the interests in each scientific scope and the intended contributions to each task cornerstone of ACTINET provided an actual overview (See below). The fact suggested that a network for actinide sciences is an indispensable establishment wel-comed by nearly all-European nuclear science laboratories.

Nearly all participating laboratories have shown their ardent interests in the scientific scope 1: the basic chemistry and physics of actinides in solution and solid phases, since the basic

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knowledge on actinides is indispensable for almost every field of nuclear science. The scien-tific scope 2: the chemistry of actinides in the geological environment appears to be of great interest for those who are directly involved in research for the geo-chemical behaviour of ac-tinides pertinent to the safe disposal of nuclear waste. Nanoscopic (molecular level) chemical reactions in multi-component aquifer systems entail special innovative approaches. The scien-tific scope 3: chemistry and physics of actinide materials under irradiation attracts only a small number of laboratories, because not so many laboratories can be involved in the trans-mutation or in the spent fuel behaviour or fuel cycle. However, all participants in the work-shops underlined the importance of this scientific scope.

The general and specific research areas of interest and the possible contributions addressed to task cornerstones are illustrated below as summarized from the survey,:

Scientific Scope

1. Chemistry and physics of actinides in solution and solid phases (25 Labs.) 2. Chemistry of actinides in the geological environment (19 Labs.) 3. Chemistry and physics of actinide materials under irradiation ( 9 Labs.)

Task cornerstones

1. Coordination and common utilization of pooled facilities (18 Labs.) 2. Training and education in actinide sciences (24 Labs.) 3. Evaluation and dissemination of knowledge (20 Labs.)

Achievements Based on the preliminary written survey and comprehensive discussion in the workshops, the scientific scope of ACTINET-5 had been consolidated and the research areas of broad interest were integrated in each of pertinent scope, as summarized below. This scope and contents were taken over without any change to ACTINET-6. (1) Chemistry and physics of actinides in solution and solid phases

The scope comprises thermodynamics, spectroscopic speciation, solid phase formation and characterization, separation chemistry (e.g. relevant to partitioning), computational & theo-retical chemistry, etc., which belong to the basic knowledge of actinides for practical use in the nuclear fuel cycle. (2) Chemistry of actinides in the geological environment The scope comprises basic geo-chemistry of actinides relevant to the long-term safety as-sessment of nuclear waste disposal, which therefore includes the basic chemical behaviour of actinides (and also long-lived fission products) in the repository environment, comprising en-gineered, geo-engineered, and geological barriers. (3) Chemistry and physics of actinide materials under irradiation This scope comprises basic alteration mechanisms involved in the fuel in present and future reactors, including high temperature reactors or transmutation devices. Evolution of the physical and chemical properties of actinide and their migration under irradiation consistently with boundary grain behaviour, etc. either under closed boundary conditions for long term interim storage or in an opened system for final disposal.

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WP 3: Organisation of education and training (Task Cornerstone 2) Objectives The main objectives are to provide education and training possibilities in the field of basic understanding of physics and chemistry of actinides as well as to optimise the use of available expertise and facilities for the training of engineers and scientists in the field. Description of work Assessment of the present situation in European countries, as documented and presented by all participants of the workshops, indicated that the education and training in the field of phys-ics and chemistry of actinides was strongly desired. General problem appraised from discus-sion in the workshops was a decline of interest in nuclear sciences in general for young gen-eration, in addition of the high cost for maintaining nuclear laboratories for well-known rea-sons. Collective endeavours, as envisaged in ACTINET, appeared to be an indispensable solution to improve actively the stagnating situation of research in actinide sciences in

urope. E Achievements The task cornerstone 2 on “training and education in actinide sciences” raised an active dis-cussion at the second ACTINET-5 workshop in Avignon, since the education possibility of nuclear sciences and its general interest are different from one country to another. It was agreed that the education was a main task of the ACTINET network. Various suggestions were addressed to intensify the education at undergraduate and graduate level at universities, promoting the mobility of young actinide scientists, organisation of summer schools, etc. All these issues have been put into the execution stage of ACTINET -6. WP 4: Management and dissemination of research activities and results Objectives To sustain and disseminate the knowledge of actinide sciences was one of the main objectives that was in the end to promote advanced research activities in Europe and hence to endorse the development of nuclear fuel cycle extended to the safe disposal of nuclear waste. Description of work Various suggestions were addressed in the workshops how to manage effectively research activities and disseminate the results within the ACTINET network, besides publication, hold-ing workshops, addressing in conferences, etc. The general primary issue was to install an effective internal communication system within ACTINET to manage actual research activi-ties and to disseminate on-going results among member laboratories.

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Achievements

The evaluation and dissemination of knowledge shall certainly promote the advanced research in actinide sciences, e.g. common benefits of intellectual instrumentation accrued within the network. The present network is supposed to build up expertise and to sustain its activity far over the period of the EC framework programme supports (more than 4 years of FP6). Through the discussion, it appeared as a consensus that the network should take the following as a responsible task:

• To make available the database, modelling tools, technical developments etc. to all par-

ticipants of the network. • To disseminate effectively the research achievements in actinide sciences to the scientific

community. • To make the effective communication available to policy makers for the long-term impor-

tance of actinide sciences in the coming generation of nuclear fuel cycle. The activity on this subject cannot be achieved within a short period of time but demands a long-term endeavour of concerted action among the ACTINET members. On-going activity of ACTINET-6 is concentrated on this area with the help of continuous evaluation supported by the scientific advisory committee.

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ACTINET FINAL Technical Report: ANNEX I 20.05.2005

3. Perspectives of ACTINET 3.1 Progression of ACTINET-5 to ACTINET-6 The initial scientific concept and groundwork of ACTINET-5 has been adopted and followed on the whole by ACTINET-6. All laboratories registered their interest of collaboration to ACTINET-5 have joined automatically ACTINET-6 as an individual member of its governing board, which functions now as an autonomous forum for the ultimate decision making. In the meantime the members have applied trice in succession the joint research projects of common interest to the net-work programme and subsequently pursuing actively collaborative research in actinide sciences above all with the benefit of utilizing the “pooled” facilities. The transition from ACTINET-5 to ACTINET-6 has thus taken place efficiently for promoting the common purpose of developing ac-tinide sciences in Europe. The successful establishment of such a network has been possible owing to the generous granting of EC financing for the autonomous network management on the one hand and to the well-shared col-laboration of all members that have joined the network each with a substantiated contribution on the other hand. 3.2 Progress in research undertaking The scientific advisory committee (SAC) composed of renowned experts in the scientific scope of ACTINET has initiated its unbiased task of evaluating research proposals. The evaluation of SAC has concentrated only on the scientific innovation and practicability within the framework of AC-TINET. The ACTINET members have already appreciated the scientific competence and objectiv-ity of the SAC activity. The three key organs of ACTINET, Governing Board, Executive Commit-tee and SAC have exercised harmoniously the management of ACTINET under reciprocal controls genially and the managing team has executed the common decisions promptly with great profi-ciency. As a result, the collaborative research activity of ACTINET is moving forward progres-sively. However, the scientific harvest has to be waited for some while, as is generally perceptible for maturing such cooperative research endeavours. The first and second calls for the collaborative research proposals have attained enthusiastic re-sponses from the ACTINET member laboratories. They are briefly summarized as follows. The third call, being under execution, is not included in this table. Call Deadline Submitted proposals

Scope Ranking a) Finally

approved Total 1 2 3 E&Tb) A B C No

1st 10.07.04 37 15 15 4 (3) 12 15 7 3 10 2nd 20.12.04 33 13 11 3 6 17 3 13 17

a) Categories: A (accepted), B (revision needed), C (rejected) b) E&T: Joint education and training project, was not considered at the first call. 3.3 How to sustain ACTINET as a long-term network

A 1


The scientific scope and task cornerstones of ACTINET-5 has been hitherto organized and executed very effectively in ACTINET-6. How to sustain such a network of already good standing to a long-term institution in Europe is a vital common mission of all ACTINET members. The sustained fi-nancial support from the EC research programme for the future growth of ACTINET is therefore indispensable. In fact the major part of financial support of the individual ACTINET members comes from the national research funds for maintaining their laboratory facilities and personnel costs. The EC fund is being used for supporting the collaboration of individual research activities only, i.e. mobility of researchers, use of the “pooled” facilities, workshops, etc. However, the continuation of EC support for networking of ACTINET is essential, since the network not only provides the possibility of co-operation among the member laboratories within Europe but also encourages the national funding for individual ACTINET members in their own countries. On the other hand, the direct and sustained national financial supports from each member country have to complement the future financial demands of ACTINET, likewise: EC programme support ⇒ ACTINET ⇐ National supports of member counties By such means, the long-term financial asset of ACTINET can be created, similar to the thermody-namic database (TDB) fund of OECD-NEA, by making plans for the endorsement of individual national research funding institutions for shared benefits. The governing board of ACTINET has to take hold of this task as a primary mission within the period of the EC framework programmes 6 and 7 by creating a special commission within the board to carry out this particular mission. 3.4 Elevation of the innovative research projects Within ACTINET, the collaboration of research is for the moment supported financially only for the mobility and partial expenses of utilizing pooled facilities. In the future, it is equally desired to support fully the innovative research projects to attain the international “prominence” of the ACTI-NET activity as a whole. SAC is capable of selecting or proposing such research projects within the scientific scope of ACTINET and accompanying their progress. The creation and promotion of ex-cellence in the research activity of ACTINET is for obvious reasons of cardinal importance. Once an innovative and promising research proposal is recognized and approved, its progress has to be financed substantially from the ACTINET fund. Special treatment of such a particular research proposal is ardently desired, which has to be not necessarily bound to formal collaboration with other laboratory, as exercised in ACTINET as a general rule, but can be pursued alone by a single laboratory. This does not mean that a necessary collaboration is discouraged. Search for an innova-tive research project entails simply an exceptional undertaking. 3.5 Expansion of international cooperation The international cooperation of ACTINET has been taking place with supporting pertinent confer-ences, workshops and summer schools organized by the members. In the future, it is also desired that ACTINET shall provide the financial support for the collaborative research with non-EU labo-ratories, evidently in the case there are shared benefits from such endeavours. Such an activity is surely to promote ACTINET internationally and in return it can also take advantage of the limited expertise resources of actinide sciences worldwide. What kind of international collaboration has to

A 2


be supported belongs of course to the decision of the governing board. However, the broadening of cooperation scope is found necessary.

A 3


FINAL TECHNICAL REPORT

“Establishment of a Network of Excellence for Actinide Sciences”

ACTINET 5 Project

ANNEXES

A 4

ACTINET FINAL Technical Report: ANNEX 20.05.2005

ANNEX I

List of Participants at the first ACTINET Workshop at Karlsruhe & Declared interest in Scientific Scopes and Task Cornerstones

Name Institution Scientific Scope Task Corner-

stone Kim, J.-I. Fanghänel, Th. Buckau, G. Denecke, M.A. Kienzler, B. Klenze, R.

Forschungszentrum Karlsruhe Institut für Nukleare Entsorgung Heinrich-von-Helmholtz-Platz 1 D-76344Eggenstein-Leopoldshafen

1+2

1+2+3

Ledermann, P.; Gerard, A.; Chaix, P.

Commissariat a l'Energie Atomique DEN/SAC/DSOE Bat 121 F-91191Gif-sur-Yvette

1+3

1+2+3

Petit, T. Commissariat a l'Energie Atomique DEN/DEC/SESC/LLCC/ Bat 315 CEA-Cadarache F-13108 Saint-Paul lez Durance

1+2+3 1+2+3

Leroy, M. CEC Joint Research Center ITU European Institute for Transuranium Elements P.O. 2340 D-76125Karlsruhe

1+2+3

1+2+3

Albinsson, Y. Chalmers University of Technology Department of Nuclear Chemistry Kemivagen 4 S-412 96Gothenburg

1+2

1+2+3

Benes, P. John, J.

Czech Technical University Department of Nuclear Chemistry Brehova 7 CZ-11519Prague 1

1+2

1+2+3

Bernhard, G.; Brend-ler, V.

Forschungszentrum Rossendorf e.V. Institut für Radiochemie P.O. Box 51 01 19 D-1314Dresden

1+2

1+2+3

Billard, I. Laboratoire de Chimie Nucleaire CRN, Bat 35 B.P. 28 F-67037Strasbourg Cedex 2

1

Bradbury, M.; Hadermann, J.

Switzerland Paul Scherrer Institut Waste Management Laboratory CH-5232Villigen

2

2+3

Bruggeman, A. SCK/CEN Belgian Nuclear Research Institute Boeretang 200 B-240Mol

1+2+3

1+2+3

Bruno, J. QuantiSci, S.L. AVDA. Universitat Autonoma 3, Parc Tecnologic del Valls E-8290Cerdanyola, Barcelona

1+2

1+2+3

A 1


Desreux, J.F. University of Liege Coordination & Radiochemistry Bt B 6, Alle de VI aot B-4000Liege

1

2

Diaz Arocas, P.; Gonzalez de la Hue-bra,

CIEMAT Departamento de Fisin Nuclear Avenida Complutense 22 E-28040Madrid

(1+2+3)

(2+3)

Grambow, B. Ecole de Mines de Nantes Laboratoire SUBATECH 4, Rue Alfred Kastler F-44307Nantes Cedex 3

1+2+3

2+3

Grenthe, I. Royal Institute of Technology Dept. of Inorganic Chemistry Teknikringen 30 S-10044Stockholm

1

1

Johansson, B. University of Uppsala Physics Department P.O. Box 530 S-75121Uppsala

1

1

Kaczorowski, D. Institute of Low Temp. & Structure Research P.O. Box 1410 PL-50-950Wroclaw

1

2+3

Kratz, J.V. Reich, T.

Johannes Gutenberg Universität Mainz Institut für Kernchemie Fritz Strassmann-Weg 2 D-55099Mainz

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Lehto, J. University of Helsinki Department of Chemistry P.O. Box 55 FIN-14Helsinki

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2

Livens, F. R. University of Manchester Department of Chemistry Oxford Road UK-Manchester M13 9PL

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Odoj, R. Forschungszentrum Jülich Institut für Sicherheitsforschung & Reaktortechnik Postfach 1913 D-52425Jülich

1

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Pashalidis, I. University of Cyprus Department of Natural Sciences Kallipoleos 70 CY-1678Nikosia

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Simoni, E. Universite Paris XI Institut de Physique Nuclaire Campus Universitaire d'Orsay / Bt 100 F-91406Orsay Cedex

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1+2+3

Stipp, S. Copenhagen University Interface Geochemistry Oster Voldgade 10 DK-1350Copenhagen K

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Türler, A. Technische Universität München Institut für Radiochemie Walther-Meissner-Str. 3 D-85747Garching

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Uhlir, J. Nuclear Research Institute CZ-250 68Rez

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Wahlgren, U. Stockholm University Institute of Physics P.O. Box 6730 S-11385Stockholm

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ANNEX II

European Commission: The 5th Framework Programme

“Establishment of a Network of Excellence for Actinide Sciences” ACTINET 5 Project

(FIR1-CT-2002-20211)

Assessment of Information on

Research areas, Scientific interest,

“Pooling” Research facilities, Education and Training,

Dissemination of Knowledge

of the EU actinide laboratories

Compiled by FZK ACTINET 5 Coordinator

Actual state in 2004

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Content

ACTINET Laboratories & Contributions intended to ACTINET 5 1. Forschungszentrum Karlsruhe, Institut für Nukleare Entsorgung (FZK / INE), Germany A 5 2. Commissariat a l'Energie Atomique CEA, DEN/SAC/DSOE, France A 8 3. CEC Joint Research Center, European Institute for Transuranium Elements (JRC / ITU) A 13 4. Paul Scherrer Institut, Waste Management Laboratory, Switzerland A 17 5. University of Manchester, Department of Chemistry, UK A 19 6. Forschungszentrum Rossendorf e.V., Institut für Radiochemie, Germany A 22 7. Ecole de Mines de Nantes, Laboratoire SUBATECH, France A 26 8. The Belgian Nuclear Research Centre (SCK•CEN), Belgium A 29 9. Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Departamento de Fisin Nuclear, Spain A 39 10. Universitat Politécnica de Catalunya (UPC), Spain A 43 11. Institut de Recherches Subatomiques (IReS) /CNRS-IN2P3, France A 46 12. Institut de Physique Nucléaire, Radiochemistry group, France A 48 13. University of Liege, Coordination & Radiochemistry, Belgium A 51 14. Forschungszentrum Jülich GmbH (FZJ), Institut für Sicherheitsforschung und Reaktortechnik , Germany A 53 15. Johannes Gutenberg Universität Mainz, Institut für Kernchemie, Germany A 54 16. Technische Universität München, Institut für Radiochemie (TUM-RCM), Germany A 56 17. University Toulouse, Laboratory for Quantum Physics (LPQ), France A 59 18. Royal Institute of Technology, Dept. of Inorganic Chemistry (KTH), Sweden A 63 19. Stockholm University, Institute of Physics, Sweden A 63 20. University of Uppsala, Physics Department, Sweden A 63 21. Chalmers University of Technology, Department of Nuclear Chemistry, Sweden A 65 22. Københavns Universitet (KU), NanoGeoScience Group of Geologisk Institut, Denmark A 67 23. University of Helsinki, Department of Chemistry, Finland A 71 24. Nuclear Research Institute, Rez plc, Czech Republic A 74 25. Czech Technical University, Department of Nuclear Chemistry, Czech Republic A 76 26. Institute of Low Temperature and Structure Research, PAS, Poland A 80 27. University of Cyprus, Department of Natural Sciences, Cyprus A 83 28. University of Naples, Analytical Chemistry, Italy A 85

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ACTINET Laboratory 1 (Core institution)

Institut für Nukleare Entsorgung (INE) / Forschungszentrum Karlsruhe (FZK)

Description of the Institution Forschungszentrum Karlsruhe GmbH (FZK) is an independent science and research institution in Germany with permanent personnel of about 3500 employees. In the area of technology and the environment, the cen-tre devotes to research and developing work in the interest of the public. FZK is a member of the Helmholtz Association of National Research Centres (HGF) and institutionally supported by the federal government and the state government of Land Baden-Wuerttemberg.

The research activities at the Institut für Nukleare Entsorgung (INE) on the topic “Safety Research for Nu-clear Waste Disposal” are integrated within the HGF Programme “Energy: Nuclear Safety Research”. Be-sides technical developments on the vitrification of high-level waste and research work on the partitioning of actinides from high-level radioactive waste, the main research activities at INE are addressed to “long-term safety of nuclear waste disposal”.

Scientific Scope 2: Chemistry of actinides in the geological environment The actinide elements, especially plutonium, make the greatest contribution to the radio-toxicity of disposed radioactive waste over long periods of time. Therefore, the research activities at INE are focused on acti-nides, especially transuranium elements, which can be handled only in special laboratories, and also some long-lived fission products (e.g. Tc-99). Basic understanding of geochemical processes and quantification of the ongoing reactions is a prerequisite for predicting long-term behavior of actinides and, therefore, essential for safety analyses. The concentration of actinides in natural aquatic systems is in the trace range (nanomol). To identify and quantify their chemical form (speciation), highly sensitive, direct laser spectroscopic speci-ation methods are developed and applied at INE.

The main research topics in actinide chemistry related to nuclear waste disposal, which are performed pres-ently at INE are summarized below.

Chemistry and Thermodynamic of Actinides in Aqueous Solution

Basis for quantification of actinides in aquatic systems is the determination of thermodynamic data (activity coefficients and equilibrium constants) for dissolved actinides species in the prevailing oxidation levels for hydrolysis and complexation reactions. For tri- and pentavalent actinides, thermodynamic data were deter-mined covering a broad range of conditions, including strong brine solutions. Corresponding sound data on the tetravalent actinides are scare for various reasons. Quite recently at INE a complete and consistent set of hydrolysis constants for An(IV) = Th, Np, Pu has been derived based on literature survey, semi-empirical correlations, solubility measurements and laser spectroscopic speciation. In summary, huge progress has been made in recent years to complete the database of aqueous actinide ions. However, in some areas such as formation of ternary complexes or reactions at elevated temperature, further efforts are required.

Interaction of Actinides with Mineral Surfaces

Sorption of radionuclides on mineral surfaces presents an important retention mechanism for the radionu-clide transport in the geosphere. However up to now, safety analyses are based on phenomenological sorp-tion approaches, a fundamental understanding of the sorption mechanism on a molecular level is missing. To overcome this drawback, reactions of actinide ions at the mineral/electrolyte interface of selected mineral phases (silica, alumina, clay, iron oxides) have been studied by a combination of classical wet-chemistry and laser-spectroscopic methods. Sorption mechanism (ion exchange, adsorption, or incorporation) as well as the formation of ternary hydroxo surface complexes has been elucidated by spectroscopic speciation. To achieve a better understanding, e.g. of the heterogeneity of binding sites and the influence of the electrostatic poten-

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tial, experiments on single crystals using surface sensitive methods (GIXAFS, TRLFS, non-linear IR spec-troscopy) are performed. The results will be used to develop a thermodynamically based surface complexa-tion model.

Co-precipitation of Actinides in Secondary Phases

Secondary phases precipitate as a consequence of the interaction of an aqueous solution with the waste ma-trix, the backfill material and the host rock, the primary minerals in the multi-barrier system. Radionuclides may co-precipitate and be incorporated into the crystal lattice of these secondary phases. To take credit of this retention mechanism for safety analysis, a detailed kinetic and thermodynamic description of the co-precipitation processes is required, including the possible formation of mobile colloidal radionuclide species. The incorporation of trivalent actinides under complete loss of their hydration water by co-precipitation from aqueous solution was observed in calcite, hydroxy aluminosilicate and powellite for the first time by laser fluorescence spectroscopy. Mixed-flow reactor experiments will be performed to synthesise secondary solid solutions under well-defined conditions, thus providing a homogeneous partition coefficient. Complemen-tary, spectroscopic (TRLFS, XAFS, XPS), microsopic (AFM) and diffraction (XRD) methods will be used to identify the incorporation mechanism on a molecular level.

Colloid Facilitated Transport of Actinides

Aquatic colloids are considered to have a considerable influence on the chemical speciation and the mobility of actinide ions in a natural aquifer. As colloid concentrations in natural groundwater usually are found in the trace concentration range, one main research activity at INE concerns the development of sufficiently sensi-tive colloid characterisation methods as laser induced breakdown detection (LIBD) and a combination of sensitive detection methods as LIBD and ICP-MS with the flow-field flow fractionation (FFFF). Another focus is laid on the elucidation of interaction mechanisms of actinide with organic/inorganic colloids, which contribute to the kinetic hindrance of dissociation reactions. Site-specific studies are related to the characteri-sation of groundwater colloids as a function of various geochemical parameters in order to derive major pa-rameters influencing colloid stability. The colloid influence on the radionuclide migration is investigated in laboratory column experiments as well as under in-situ conditions (e.g. Äspö, HRL, Sweden and Grimsel Test Site, GTS, Switzerland).

Development and application of speciation methods

Understanding of relevant geochemical processes on a molecular level necessitates the characterisation and quantification of the chemical state of the species involved. Laser spectroscopic speciation methods (laser-induced photo-acoustic spectroscopy (LPAS) and time resolved laser fluorescence spectroscopy (TRLFS)) are selective and sensitive for the speciation of many actinide oxidation states. In particular TRLFS on Cm(III) by has been proven as a very powerful tool for speciation in solution, at mineral/electrolyte inter-faces and in secondary phases. Laser-induced breakdown detection (LIBD) has been developed at INE for the ultra-sensitive quantification of small colloidal particles (>10nm). Surface-sensitive non-linear IR spec-troscopy / microscopy is presently under development at INE for the speciation of surface functional groups. X-ray fine structure spectroscopy (EXAFS, XANES) is employed to derive valuable structural information on the coordination environment of the actinide ions. An important impact on the future spectroscopic capa-bilities at INE will be expected by commissioning the active beam-line at the ANKA synchrotron source in 2004. Development and adoption of new spectroscopic methods seem to be indispensable for future devel-opment in actinide research.

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Task cornerstone 1: “Pooled Facilities” at FZK / INE

Handling of radioactive material

INE is licensed to work with radionuclides of all types up to 1010 times the exemption level in total, includ-ing high active glass, spent fuel and smaller amounts of nuclear fuel. Laboratories with more than 800 m2 are available in the controlled area to handle radioactive material at various level of activity, to work under spe-cial (inert-gas) conditions, and to use numerous analytical tools and special methods.

• Shielded hot cells (7) for remote handling and experiments with high active glass and spent fuel.

• Alpha-glove boxes (42) for experiments with actinides.

• Alpha glove boxes (20 out of 42) with inert gas atmosphere (Ar or Ar/CO2) for experiments under controlled conditions

Analytical and Speciation Equipment

• INE is provided with a broad range of analytical equipment for performing analyses related to research on actinide material including high active waste and spent fuel elements. Most of the instruments and methods have been adapted to be applicable for radioactive samples and are located within the con-trolled area of the institute.

• INE has a number of instruments for radio analyses such as α-,β-,γ-spectrometers. For low level measurements both anti-Compton-γ-spectrometry and liquid scintillation counting is available.

• Trace analyses and isotope analyses are performed with atomic absorption spectrometry (AAS), ICP-atom emission spectrometry (ICP-AES), ICP-mass spectrometry (ICP-MS) and X-ray fluorescence analysis (RFA).

• Numerous instruments for surface/solid-state analyses are available at INE, including a scanning elec-tron microscope (SEM) with an energy dispersive detector, an ESCA-/Auger-spectrometer, x-ray dif-fractometers, atomic force microscopy (AFM), and laser-ablation coupled to ICP-MS.

• For the laser-spectroscopic speciation of actinide ions various tuneable pulsed laser systems and time-gated optical multi-channel analyzers are employed. Most of the lasers and detectors are coupled via optical fibres to the sample cell within inert-gas glove boxes, thus separating spectroscopic and chemi-cal part from each other. Actinide speciation is also performed by conventional UV/Vis/NIR spectros-copy and by capillary electrophoresis.

• For the quantification of colloids various home made instrumentations for laser-induced breakdown detection (LIBD), a flow-field flow fractionation (FFFF) coupled to UV/Vis, LIBD and ICP-MS de-tection and dynamic light-scattering are available.

• Surface-sensitive non-linear IR spectroscopy / microscopy is presently under development at INE for the speciation of surface functional groups.

• At the FZK synchrotron radiation source ANKA a multifunctional XAFS beam-line dedicated for the study of actinides (Pa, Th, U, Np, Pu, Am and Cm up to 106 times the exemption level) is under con-struction. After commissioning the beam-line in 2004, a versatile tool for actinide sciences will be available in the direct vicinity to the active labs at INE.

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Commissariat a l’Energie Atomique (CEA)

Scientific Scope 3: Basic properties and evolution of actinide materials under irradiation The aim of this project is to yield a basic set of data in the field of oxide fuel behaviour. Two distinct areas of research have been identified. The first pertains to data and experiments relative to the behaviour in uranium dioxide of helium and volatile fission products (Xe, Kr, I, Cs). The second concerns mechanical data. The data and results this programme generates is aimed at improving our understanding of the complex phenom-ena that are liable to occur in nuclear fuels under most operating conditions and will provide quantitative and qualitative support for the development of increasingly mechanistic and physically based fuel behaviour models.

PART I: A separate effects study of the behaviour of helium and volatile fission products in uranium oxides

Aim and scope The main objective of this programme is to generate a comprehensive set of basic physical data relative to the behaviour in uranium dioxide of volatile fission products and helium. Access to these data is essential to fuel behaviour modelling under all operating conditions pertaining to in-pile and interim or long-term storage situations.

The project aims to study the consequence of both temperature and radiation on the diffusional properties of helium, xenon, krypton, iodine and caesium in uranium dioxide.

Four areas of research have a priori been identified:

2.1. thermal diffusion of helium, iodine, xenon, krypton, and caesium.

2.2. irradiation induced or enhanced diffusion. The effects of swift and low energy ions will be studied separately.

2.3. the interaction between a given volatile element and other elements simulating the presence of fis-sion products. The presence of fission gas bubbles or metallic precipitates and their consequences on element migration will be of particular interest here.

2.4. the effects of temperature and radiation on fission gas bubble stability.

General methodology The mechanisms that control the behaviour of volatile elements in uranium oxide fuels are complex, very often coupled and the effects they have are virtually impossible to quantify independently in irradiated mate-rials. On the other hand the increasingly sophisticated models that are developed to simulate the behaviour of such volatile fission products describe mechanisms that are very often only assumed. The values of the physical parameters associated with the basic mechanisms described are only known to within an order of magnitude at the best of times.

The idea therefore is to set up increasingly complex separate effects experiments on uranium dioxide sam-ples in which "no or hardly any" fission reactions have taken place. Working on un-irradiated materials will enable the use of a very wide variety of characterisation techniques that are usually impossible or very diffi-cult to apply to in-pile irradiated samples. This will help ascertain the effects of each type of treatment on the samples, be they physical, structural or chemical. A thorough and comprehensive characterisation of the samples will provide a means of controlling experimental conditions thus avoiding any misinterpretation of results.

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Single crystals or polycrystalline-sintered samples will be used. Several techniques may be used to introduce the elements of interest:

3.1. Ion implantations may be used to create tailored concentrations at the sample surface,

3.2. In the case of helium, infusion devices may also provide an adequate means.

In most cases, stable isotopes will be used. However, it is also possible and in some cases preferable to work with trace radioactive isotopes.

The samples containing the element whose behaviour is being studied will then undergo a series of either anneals, or ion bombardments, or both. The ion bombardments will provide a means of simulating the effects of fission fragments in-pile or α decay under long-term storage conditions (α particles or recoil atoms). The elemental concentrations (or concentration profiles whenever possible) will be characterised prior and fol-lowing each type of treatment.

Experimental techniques envisaged The following table contains a non-exhaustive list of experimental (mainly surface characterisation and nu-clear) techniques that will be available for concerted use through the aggregation of a number of laboratories that have developed a specific expertise in a field. Implementation of various techniques will yield specific information on a physical quantity. In addition, the use of different techniques to access the same or similar physical quantities can provide a means of 'cross-validation' or will enrich the analysis by possibly shedding light on a process from a different angle.

I) Element insertion, detection and sample characterisation techniques Introduction

Diffusion studies of volatile elements in UO2 are rather complex to carry out mainly because most of the elements of interest are insoluble and therefore precipitate in bubbles at relatively low concentrations. In addition to this, the actual introduction of the element in the material will usually introduce defects which affects the diffusive properties of the element.

Finally, the behaviour of gas atoms at grain boundaries is notably different from what it is within the grain so that grain boundary behaviour has to be assessed independently. The latter difficulty may be circumvented by using single crystals and comparing the results with experiments run under the same conditions but in-volving polycrystalline samples.

The two former difficulties necessitate the use of an experimental technique that is sensitive enough to be operative at very low element concentrations. When no experimental technique is available, then a method-ology involving modelling the coupled phenomena and bubble characterisation will be necessary.

Fission products

Regarding fission gases (Kr or Xe), it appears that working with radioactive trace elements is the only means of avoiding bubble precipitation. Radioactive isotopes can be introduced in several ways:

I. Ion implantation using a radioactive source

II. Nuclear reaction recoil atoms

Concerning the latter method, specific nuclear reactions can be chosen to produce the desired trace radioac-tive element. Alternatively, fission of very small amount 235U atoms could also be used.

Using SIMS, it is possible to work at iodine concentrations sufficiently low to avoid bubble precipitation. Caesium could also possibly be studied using SIMS at very low concentrations. The advantage here lies in the fact that there are no experimental complications related to the use of radioactive material and that a SIMS analysis yields a depth profile which provides more information than the fractional release alone.

Helium

Introduction of this element in the material can be done directly through ion implantation or using an infu-sion device (high helium pressure furnace). The effect of α-decay on the oxide matrix may also be ap-

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proached by doping samples with α-emitters such as 238Pu. The advantage of an infusion method is that no structural defects are introduced in the process. Mass spectrometry can then be applied to monitoring helium desorption kinetics.

Nuclear Reaction Analysis (NRA) can also provide a means of assessing the amount of 3He contained in a sample. This technique is capable of yielding concentration profiles or concentration profile changes.

Sample characterisation

The energy of implanted ions be they radioactive or stable is usually in the 0.5-1MeV range. The atoms are therefore implanted near the surface. This requires the physical and chemical state of the surface (roughness, oxidation, point defects etc.) to be monitored with the utmost care to avoid any experimental artefacts. Sam-ples must be annealed prior to initial element implantation to eliminate surface roughness, preferably in a reducing atmosphere so as to avoid any risk of surface oxidation. XPS or EXAFS may be used to character-ise the state of the surface with respect to oxidation and PAS could be used to assess the presence of vacancy type point defects in the material.

II) Thermal and irradiation enhanced diffusion Low doses

Xe, I, or Cs implanted-samples will be annealed at various temperatures above which thermal diffusion is expected. γ spectrometry will be used to monitor the release kinetics from the samples of radioactive ele-ments. SIMS will be used to assess I or Cs concentration profile change for different hold times.

Enhanced diffusion will be studied by pre-faulting the material which can be done by implanting elements such as rare-earths that will damage the oxide matrix but remain immobile in the course of the anneal. Defect concentrations and atom diffusion will whenever possible be correlated.

Higher doses: Diffusion-trapping in the presence of rare gas bubbles

Thermal behaviour at higher doses will also be studied. Implanting stable isotopes at higher doses and then annealing the samples may actually do this. PIXE or EPMA (resp. SIMS) could no doubt be used to monitor the total amount (resp. local concentration) of the volatile species remaining in the sample. At high doses however, precipitation is most likely to occur and bubble characterisation will be necessary. This may be done either through TEM observations of thin samples or by using SAXS. In addition to bubble concentra-tions and sizes, this latter technique could in principle also provide important information such as the pres-sure inside the precipitated bubbles. Stable and radioactive isotopes could also be used simultaneously and the results directly compared to the equivalent experiment at lower doses.

Grain boundary effects

The effect of grain boundaries could in principle be studied by running parallel experiments on single crystal and sintered polycrystalline samples. However, the depth at which elements can be implanted (100-300nm) would preclude any quantitative assessment of the role of grain boundaries at least as far as Xe, Kr, Cs or I is concerned.

The case of helium

Helium stands out from the rest of the elements studied if only from a practical point of view because it can be introduced in samples either through high temperature & pressure anneals (infusion), α doping, or through ion implantation at distances from the sample surface in the 1-2µm ranges. This latter point is sig-nificant, since one can expect grain boundaries to have a greater impact on annealing than for sub-surface implanted specimens. Of course the quantity of helium remaining in the sample will be measured either us-ing NRA or TDS.

Parametric studies involving the introduction of point defects or the precipitation of bubbles and the quantifi-cation of their role on diffusion kinetics should also be undertaken.

III) Irradiation induced diffusion In this and the following section, irradiation effects (fission fragment energy loss or α decay) are simulated either through the use of swift heavy ion accelerators (mainly for the study of electronic effects) or through the use of more standard lower energy implanters (for the study of collision cascades).

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Samples will first of all be implanted with the element whose behaviour is being studied and then irradiated with high or low energy ions. The changes in concentration profiles are then ascertained using the relevant technique (NRA, SIMS). Note that controlling the energy or electronic stopping power of the incident ion can run parametric experiments.

The effects of temperature may be studied in conjunction with radiation effects either by annealing the sam-ples previously irradiated or by simultaneously irradiating and annealing the samples at the required temperature.

IV) Fission gas and helium bubble stability Crucial to the understanding and modelling of the behaviour of volatile elements in uranium dioxide is the knowledge of the kinetics of bubble precipitation and re-solution. Such information is a prerequisite to any mechanistic approach to fission gas behaviour modelling. This section is an essential part of the study and will have to be carried out in parallel.

Implanted samples will be annealed at different temperatures and hold times and then studied in TEM or using a SAXS or EXAFS technique. Bubble size distributions will be determined.

Implanted samples will also be irradiated with swift heavy ions in order verify the relevance of heterogene-ous nucleation. Conversely, pre-annealed samples containing tailored bubble populations will be irradiated in order to quantify radiation effects on bubble resolution.

V) Modelling and simulation Modelling is an integral part of this project and will be performed at several different scales. Firstly kinetic-diffusion models, similar in principle to those used in fuel behaviour applications will be used to interpret the various experiments run. This will serve the double purpose of interpreting the above-mentioned experiments and producing data which can directly be 'injected into' fuel behaviour applications. When appropriate, multi-dimensional modelling may be introduced in order for instance, to mechanistically describe the behav-iour of the volatile products studied at the grain boundaries.

Complementary to this approach, molecular dynamics will provide a useful description of collision cascades and their effects on the mobility of fission products. Finally ab initio calculations will be used to evaluate physical quantities such as incorporation or solution energies, which in the case of helium may directly be assessed against data generated from infusion experiments.

PART II: Micro-indentation programme

Introduction Equipment designed for micro-indentation testing with the load being force or displacement controlled is now operational at the ITU in Karlsruhe. This equipment is set up in a hot cell and can be applied to tensile, creep or relaxation testing on a volume of solid of a few cubic microns and at temperatures in the 20°C-1200°C range.

Use of this equipment to determine the irradiation-induced changes in mechanical properties appears to be promising. Furthermore, coupled to a micro-acoustic device it would be possible to determine the full range of mechanical properties (elastic and visco-plastic) over the entire pellet radius.

This paper lays down the various stages and the strategy required to ascertain the effects of burn-up on the fuel visco-plastic behaviour law which itself was determined through compression tests run on un-irradiated material and subsequently validated through bending tests.

The burn-up will eventually be replaced by calculated physical quantities such as the concentration in fission products in solution, metallic precipitate or fission gas bubble concentrations, or radiation damage 'indica-tors' (dislocation density, point defect concentrations). The MOGADOR fuel behaviour model could provide this information.

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Strategy The study of burn-up effects is undertaken in such a way as to identify the effect of different phenomena separately. Three types of tests are currently envisaged:

1. Standard tests on SIMFUELS enabling the study of the impact of precipitates and elements in solution

2. Tests on ion irradiated materials in order to quantify radiation effects

3. Micro-indentation tests on irradiated fuels which would provide a complete validation of the visco-plastic fuel behaviour law.

The micro-indentation tests are therefore an integral part of a wider programme aimed at establishing the effects of burn-up on the fuel behaviour law. The number of reactor cycles over which fuel rods are irradi-ated could therefore be explicitly taken into account in the modelling.

Feasibility on un-irradiated material

This stage should proceed as follows: a parametric study involving different grain sizes and pore-size distri-butions will be run for porosity effects, grain size effects, temperature effects and different types of loading.

All the above tests will be modelled. Initially the fuel behaviour law developed from standard creep tests and currently used will be applied to model the experimental data generated. The parameters the law comprises could then be reassessed and used as reference for the rest of the study. At this stage, approximately twenty samples will be needed, each of which will be extensively characterised.

Out-of-pile tests on irradiated material

Several types of fuels (UO2 based, MOX, Gd or Cr doped) will be tested. For each type of fuel six burn-up ranges will be studied. At each burn-up level, creep and tensile tests will be undertaken at different tempera-tures and positions along the pellet radius.

A micro-acoustic analysis will be run prior to the mechanical tests proper in order to evaluate the apparent rigidity of the area of fuel studied. These tests will be run at room temperature and at the same locations as the indentation tests.

Chemical and physical characterisations (pore and bubble size distributions in particular) will be performed at the location where the mechanical tests are carried out. Post-test micro-structural characterisations based on SEM and TEM observations could also give an indication of the type of deformation mechanisms in-volved.

Equipment required As regards micro-acoustic, it will be necessary to set up a rig to test un-irradiated materials. An electronic control system must also be acquired which will be shared with the equivalent device set up in the hot cells.

There is also a need for irradiated samples on which out-of-pile tests can be carried out and which are com-patible with the above described test grid.

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European Commission – Directorate General JRC

Joint Research Center Institute for Transuranium Elements

Scientific Objectives

In the frame of the EURATOM programme and in line with its mission, the Institute for Transuranium Ele-ments responds to the concerns of the European citizens by performing customer driven research and basic and exploratory research related to its core competences. The research areas are described briefly below.

Management of spent nuclear fuel and highly active nuclear waste The two approaches for spent nuclear fuel management favoured by the Member States of the European Un-ion are studied at ITU:

1. Intermediate storage with subsequent conditioning for final disposal and

2. Intermediate storage with subsequent reprocessing before final disposal in geological formations.

The behaviour of irradiated fuel under conditions of direct long-term disposal requires further investigation with regard to basic processes involved. Safety relevant data on the corrosion and dissolution behaviour of waste under realistic conditions and over a time period of 60-200 years are of utmost importance to deter-mine the radiotoxic potential and assess the consequences of storage over extended periods of time.

The lowering of the radio-toxicity of highly active waste by reducing the quantity of actinides and other long-lived radioactive elements is another objective addressed in this research programme. Separating long-lived nuclides from the waste, recycling them with appropriate fuels in reactors for transmuting or “burning” them is therefore considered an important waste management option.

ITU is developing a partitioning and transmutation programme in close co-operation with its European, Japa-nese and US.

The first goal of this activity is to define and experimentally assess the advanced reprocessing methods for commercial fuels of the first stratum, and both aqueous and pyro-metallurgical partitioning techniques for fuels and targets for actinides transmutation in the multi-recycling strategy.

The second goal of this activity is to define and characterise the most suitable materials for transmutation of transuranium elements, in order to assess the technical feasibility of P&T. This objective requires further investigation on the manufacturing of fuels and targets for irradiation testing, and their material property determinations, including their reprocessing ability. This objective also applies for the recycling and degrad-ing of the plutonium obtained from the destruction of atomic weapons. This task will include a contribution to setting up advanced methods for transmutation; through basic physics calculations and related experimentation.

The third, technically connected objective of this programme is to define, fabricate and characterise matrices for the conditioning and long-term storage (up to their final disposal) of minor actinides and long-lived fis-sion products.

Safety of nuclear fuel Due to the extended use nuclear fuel in existing reactors ITU studies the behaviour of nuclear fuels under high burn-up or accidental conditions. Databases are needed on the properties for UO2 (at b.u. >100 GWd/t) and MOX (at b.u. > 50 GWd/t) such as: high-temperature thermophysical properties, melting point behaviour

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of high burn-up fuel and corium, high temperature mechanical properties, swelling and gas release under transient conditions, RIM effect investigations…

This contributes to a better use of energy resources, and to an overall reduction of nuclear waste and trans-port requirements.

Modelling is an integral part of safety studies and ITU develops the TRANSURANUS fuel performance code. This code is presently extended with new data for MOX and UO2 at high burn-up and in transient con-ditions. Training of users is a very important task and special attention is given to scientists from Candidate Countries. Through participation in PHEBUS, the reactor meltdown simulation project, ITU gains new in-sights into the behaviour of melted fuel rod bundles and of the behaviour of aerosol deposits in the primary circuit.

ITU contributes also to the development and use of advanced fuels in order to improve fuel safety and reduce civil and military stockpiles of plutonium. Together with European partners, ITU is developing advanced fuel fabrication techniques based on the sol-gel process and carbo-thermal reduction.

Nuclear Safeguards and Non-proliferation Preventing proliferation of nuclear material is a worldwide task shared by the European Commission’s Eura-tom and the International Atomic Energy Agency (IAEA) inspectorates. They are responsible for imple-menting safeguards measures to control the use of nuclear materials within the European Union and world-wide.

As a long-time partner, ITU continues to provide analytical assistance and expertise on plutonium handling facilities, such as reprocessing or MOX fuel fabrication plants. As the Commission’s Analytical Reference Laboratory in safeguards ITU develops new analytical tools to analyse and characterise different nuclear materials, perfecting them to perform forensic analysis and identify seized, illicit material. ITU fulfilled its commitment for designing and installing an in situ laboratory for safeguards measurements and continues to operate the On-Site Laboratory at BNFL’s Sellafield reprocessing plant and the Laboratoire sur Site at Co-gema’s La Hague plant.

ITU is closely involved in the international efforts to detect clandestine activities and to combat the illicit trafficking of nuclear materials. ITUs activities in this area are co-ordinated through participation in the P-8 International Technical Working Group. Together with IAEA, ITU contributes to the development and im-plementation of a model action plan for the seizure of nuclear material in the future Member States to the European Union. The ITU nuclear materials databank is continuously extended by integrating data received from industry in the Member States, from Russia, Ukraine and from candidate Countries.

In the areas of illicit trafficking of nuclear materials, illicit waste dumping and environmental impact of ra-dioactive releases ITU improves the selectivity, sensitivity and accuracy of detection and measurement methods to better identify the origin of the materials.

Radioactivity in the environment There is a need for validated analytical methods dedicated to traces and ultra-traces of actinide elements in environmental samples. ITU is developing analytical methodology for isotopic determination of actinides in particles (fission tracks), in soils and in slugs to provide the scientific community, dealing with radioactivity in the environment with the necessary assessed analytical protocols. A special attention is given to the devel-opment of separation and pre-concentration techniques for improving the limits of determination of actinide elements in various matrices. This research is carried out in collaboration with institutional research centres and universities from Members States and Candidate Countries.

Maintaining and acquiring competence in basic actinide research Any technological problem solving or improvement process requires a thorough understanding of the basic phenomena. Typically an evolution from macroscopic to meso- and microscopic investigation is required and a coupling between the different disciplines and scales of research within one institute is of vital impor-

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tance. A good knowledge of fundamental physical, chemical and materials science data on actinides and ac-tinide-containing products, i.e. nuclear fuels and nuclear waste, is the basis for addressing nuclear issues at ITU.

ITU scientists aim at developing an understanding of these properties, including the electronic structure of actinides and actinide compounds and four major research topics are developed:

Preparation and characterisation of actinide elements and compounds:

Concerning fuel cycle safety actinide research contributes to the basic understanding by the structural studies of actinide compounds in both, polycrystalline and single crystals forms. ITU activity aims at providing these materials for both internal and external “customers”.

Material Science:

Present systems (safety, optimisation of lifetime and burn-up), future systems (new concepts and new proc-esses), fuel behaviour under irradiation, intermediate storage, long term storage, targets for transmutation, waste management, etc require material science data on actinides and actinide-containing products. ITU sci-entists aim at developing a profound understanding of thermo-physical and thermodynamic properties of refractory nuclear materials.

Investigation of the solid-state physics of actinides:

From a theoretical point of view, expanding the knowledge on 5f elements is a task of ITU as these elements possess magnetic and superconductive properties not expected using the description of f orbitals derived from the properties of 4f (lanthanides) elements.

Surface and Interface Science of Actinide materials:

Many processes in the nuclear fuel cycle are dependent on the behaviour of actinide elements in different chemical and physical forms. Of particular interest are phenomena at the interface (fuel-cladding interac-tions, lixiviation of spent fuel in intermediate or final disposal…). Therefore tailor-made thin films, clusters of atoms or multi-layers of actinides are studied at ITU.

With the creation of the Actinide User Laboratory, ITU gives active support to the scientific community by giving access to its facilities to host scientists. Particular attention is given to training the next generation of scientists, especially those from Member States and Candidates Countries, which lack of nuclear installations suitable for training.

Health and nuclear medicine As a spin-off of the Institute’s experience in radiochemistry in general and radionuclide separation in particu-lar, quality controlled, safe and reliable separation techniques have been developed for the isolation of spe-cific radionuclides, for application in nuclear medicine. The high interest in the cancer-cell killing potential of such radionuclides (when coupled to specific targeting carriers) caused ITU to embark on dedicated production processes for such radioisotopes, the development of high performance radionuclide generators and on the efficient chelation of the compounds. ITU also continues to support the execution of clinical trials with these products and fosters the ability for widespread use of such new therapeutical treatment (known under alpha-immunotherapy).

Equipment and Facilities

• Hot cells for the handling and studies of genuine fuel pins and examination and dissolution of real

spent fuel.

• Minor Actinide Laboratory. Preparation of fuel pellets and transmutation targets. (Max 150 g of Am, 5 g of Cm)

• Power laser installation for the thermophysical studies of fuel, spent fuel, inert matrices….

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• Full analytical equipment for destructive and non-destructive analysis of actinides elements

• User Lab:

Samples Preparation

Samples Characterization

Physical Properties Measurements

- Arc melting furnaces

- High-temperature facilities

- Single Crystal Growth (Mineralisation,- Vapor Transport processes)

- Thin films

- Thin Layers

- X-ray diffraction (Powder, Single Crystals)

- High Temperature X-ray diffraction

- High Pressure X-ray diffraction

- Mössbauer Spectroscopy (237Np, down to 1.5K)

- Electrical resistivity (Low, High-temperature 1.5K to 1000K, High Pressure )

- Magnetization (SQUID) (2K to 700K and up to 7 Tesla)

- Specific heat (0.3K to 200K and up to 9T)

- Photoelectron spectroscopy (XPS, UPS, AES, ISS)

- Theoretical Modeling

• Pyro-reprocessing and liquid-liquid separation units

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ACTINET Laboratory 4

Paul Scherrer Institut (PSI), Waste Management Laboratory

Activities The Waste Management Laboratory has two tasks: (i) to carry out an R&D programme strengthening the scientific basis for nuclear waste management, and (ii) to build and then run – together with the Swiss Light Source team – a micro-XAS beam-line.

In its first task, the Laboratory serves an important national role by supporting the Swiss Federal Govern-ment and Nagra in their tasks to safely dispose of wastes from medical, industrial and research applications as well as from nuclear power plants. The activities are in fundamental repository chemistry, chemistry and physics of radionuclides at geological interfaces and radionuclide transport and retardation in geological me-dia and man-made repository barriers. The work performed is a balanced combination of experimental activi-ties in dedicated radioactive laboratories and the field, and theoretical modelling. The work is directed to-wards repository projects and the results find their application in comprehensive performance assessments carried out by Nagra.

In the following we sketch the activities related to the physics and chemistry of actinides (and long-lived fission products).

Fundamental repository chemistry

We have developed a thermodynamic data-base with special reference to applications in repository projects. This requires constant updating and work on its consistency. We are further developing a new geochemical code, GEMS/PSI, based on Gibbs energy minimisation. The tool allows speciation in the aqueous phase, reactions at surfaces (sorption and solid solution formation) as well as incongruent dissolution of solids to be considered simultaneously.

Chemistry at the solid/liquid interface

We are measuring sorption and desorption processes on clay and cement minerals, on argillaceous rocks, bentonite and hardened cement paste. We have developed sorption models to describe the uptake processes on a mechanistic basis. Our involvement in XAS grew out of this activity. The long-term goal is to develop a thermodynamic based sorption data-base.

Radionuclide transport

We are performing laboratory and field experiments to elucidate diffusion and sorption processes in compact systems, particularly for argillaceous rocks and cement systems. We are developing the corresponding mod-els, especially coupling chemical interactions and physical transport mechanisms with an emphasis on de-scribing the influence of geometrical factors.

The micro-XAS beam-line

At the Swiss Light Source we are presently building a beam-line dedicated to micro-beam X-ray absorption spectroscopy. The optical concept is optimised with regard to sub-micron spatial resolution and a mono-chromatic X-ray beam in the energy range from 4 keV to 20 keV. The beam-line will also serve as the opti-cal system to produce hard X-ray pulses of about 100 fs duration. The beam-line will allow for measure-ments of active samples. It will come into operation towards the end of 2004.

Resources Staff: 27 positions (of which 18 are academics) 2 PhD students from summer 2003 & possibility for further PhD students and post-docs

Infrastructure: 5 class A labs with equipment (5 atmosphere controlled glove box lines; centrifuges, beta/gamma counters)

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From the end of 2004: micro-XAS beam-line at the SLS; measurement facilities for active samples, lab for sample preparation

Scientific programme in the next 5 to 10 years in the actinides field We see our main contribution in scope 2, though there is some overlap with scope 1. The topics of scope 3 are outside our interest.

The needs and scope have been well presented by the main speakers at the 1st ACTINET Workshop – and discussed. We do not have any essentially new thoughts in this respect. Based on our mission, knowledge and resources we are especially interested in the following:

• Aquatic chemistry and thermodynamics development of tools and data bases

• Interaction of actinides with mineral and rock surfaces experiments and modelling; development of sorption database for PA.

• Formation of secondary phases experiments and modelling

• Reactive transport of actinides in natural and man-made barriers experiments and modelling

• Applicability of lab results to natural systems experiments and modelling

• Development of experimental and theoretical tools X-ray absorption spectroscopy, molecular modellingi

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University of Manchester- Centre for Radiochemistry Research (CRR) Background Information Laboratories and Expertise: 3 Controlled Area laboratories (15 fume-hoods). Working limits are essentially BNFL fume-hood limits (broadly 10 mg 237Np, 1 mg 242Pu in routine experiments, no powders, 50-100 mg 237Np or 242Pu in stocks; also 99Tc in comparable amounts to Np). Np and Tc chemistry on this scale is proven, Pu chemistry to be developed over the next year. Th and U chemistry are essentially unlimited.

One Supervised Area laboratory (6 fume-hoods) for low level separations and radiotracer experiments. Al-pha- and low background gamma spectroscopy (HPGe and REGe), low-level alpha/beta liquid scintillation counting. Actinide (236U, 237Np, Pu) accelerator mass spectrometry at ANU, Canberra, Australia.

Equipment for use with Th, U, Np, Pu, Tc includes multinuclear NMR (mainly 1H, 13C, 15N, 17O, 19F, 31P, 99Tc), UV-visible-near IR (solid and solution), ir/Raman (solid and solution) spectroscopy, titration micro-calorimeter, UV-visible and near-IR luminescence, electrochemistry (CV and CPE), single crystal XRD. Np and Pu EPR (powder, single crystal and solution phase) being developed. EXAFS experiments at Daresbury (U, Th, Tc) and ESRF (U, Np).

Equipment for use with U, Th includes in situ UV-visible spectroscopy in high temperature furnace, inert atmosphere dry box. Specialist microscale Schlenk apparatus being developed for Np, Pu.

Close links to Earth Sciences Department, which has excellent facilities for SEM (including ESEM), TEM, SPM, XPS for U and Th active materials and strong geo-microbiology. The CRR has recently been selected to lead the development of a UK Actinide Chemistry network (involving 7 academic and industrial partners).

Expertise- synthesis (aqueous and non-aqueous media), low oxidation state chemistry, electrochemistry, spectro-electrochemistry, spectroscopy, luminescence, separations, high and low T molten salts, analytical separations, colloid chemistry.

Financial Information. The CRR is now 3 ¾ years old and is on track to deliver a 16 M euro, 5 year Business Plan. The principal items in the plan are: Capital (refurbishment and major equipment) 4 M euro, Staff (academic and technical) 2.5 M euro, Project funding (Postdoctoral fellows and PhD students) 9.5 M euro.

Interaction of our research programmes with ACTINET. Items italicised are significant elements of our pro-gramme which are of less general interest in ACTINET.

Cornerstones. Pooled Facilities.

We are in a position to accommodate limited numbers of visitors from ACTINET. We can provide training, technical and scientific support. While we clearly cannot offer the same capability as the Core Laboratories, I suspect it may be easier to work in our laboratories (if our experience with BNFL is typical, there is exten-sive training, which takes about 2 months, required before we get anyone into a BNFL laboratory whereas we can get people into our labs in a couple of weeks).

Training and Education.

We teach introductory radiochemistry (8 lectures) to 140, 2nd year undergraduates and advanced radiochem-istry (24 lectures) to 100, 3rd/4th year undergraduates. There is a radiochemistry practical (1 week) in the 3rd year practical course and we also run 8-10, 24 week projects for 4th year students.

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Scientific Contributions Scope 1. Chemistry and Physics of Actinides

i) High and low temperature molten salts (synthesis, characterisation, electrochemistry and spectroscopy of actinides in molten salts)

ii) Synthesis of selective ligands for separation using both combinatorial and classical methodologies

iii) Purex chemistry- chemistry of polyoxometalate complexes, TBP degradation products, “third phase” formation

iv) Interaction with surfaces- mechanisms of contamination, decontamination

v) Non-aqueous actinyl chemistry- actinyl ions with soft donor atoms and in unusual coordination environ-ments

vi) Application of theoretical tools (QM, MM, QM/MM hybrid methods) in support of the above (redox, ligand selectivity, solvation, complexation). Incorporation of relativistic and spin-orbit effects in codes.

Scope 2. Actinides in the Geological Environment

i) Interactions with mineral surfaces/formation of secondary phases- sorption, surface complexation, surface mediated redox processes, spectroscopic characterisation, thermodynamic modelling

ii) Mechanisms of glass corrosion- experimental and kinetic modelling studies on glass simulants

iii) Generation, stability and mobility of colloids- kinetics of formation of inorganic colloids; growth and structural evolution followed by synchrotron radiation; interactions with cements. Actinide chemistry in ce-ment leachates and Magnox sludges.

iv) Properties of non-glass waste forms- actinide speciation in the waste form, leaching, colloid generation.

v) Kinetics and thermodynamics of complexation with humics; reversibility; enthalpies and entropies; com-parison of laboratory experiments with TU-containing humics from the natural environment

vi) Thermodynamic and kinetic modelling; coupled speciation/transport modelling; simulation of column transport experiments

vii) Field studies of actinide-contaminated environments (northeast Irish Sea Basin); remobilisation in sedi-ments; interactions with the microbial community

viii) Interactions of actinides with subsurface micro-organisms; biological reduction, biotransformation; biochemistry and genetics of transformation.

ix) Application of surface analytical techniques (XPS, ESEM, SPM, synchrotron).

x) Application of theoretical tools (QM, MM, QM/MM hybrid methods) to the above; development of meth-ods for use in large periodic systems.

Comments on Cornerstones. If this network is to operate effectively, there has to be a common training requirement for access to the pooled facilities, which needs to be agreed between the partners (i.e. if a student is deemed competent to work in ITU they have to be acceptable to Atalante as well without further extensive training). This training has to be readily accessible to all members of the network (i.e. it is not reasonable to expect a student to travel from Greece to Marcoule several times over a couple of months to attend a series of courses before getting access to the labs). This training has also to take account of the tremendous variability in background knowledge of students- the network may have to accommodate people with little or no physical science background, let alone knowledge of radioactivity (for example, Environmental Science students).

In addition, there are two components of training- one is generic (ionising radiation, radioactive materials etc.) and the other is site- (and perhaps even laboratory-) specific (if you hear this alarm you need to do this). There may also be a need for specific experiment-related training (active glove-box, Pu safety).

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I suggest we can identify three levels of training-

1. Introductory, generic instruction, which may have more than one component, and which can probably be done over the internet.

2. Classroom-based training (examples might include radiochemical technique, behavioural safety, fire fight-ing, monitoring, site alarms), which cannot be done over the internet but could be concentrated into, say, a 1 week course which was run 2-3 times a year.

Satisfactory completion of Levels 1 and 2 would signify that an individual had an acceptable level of back-ground knowledge to progress to Level 3 (specific practical training in an active laboratory)

3. Laboratory-specific and primarily practical training. Essentially working in a hot lab under close supervi-sion, learning laboratory technique. This would take place at whichever facility the individual was going to use and be geared specifically to that individual’s needs. Based on our experience with BNFL, we would expect to need about 1 week supervised working before an individual was able to work independently in an active fume-hood and another couple of weeks for Pu glove-box working. Supervising one person through this process takes 30-50% of a supervising technician’s time.

All components need to be assessed and a formal record of satisfactory completion must be assembled (simi-lar to our Proficiency Passport scheme).

I can see three ways in which this network might function- the students get access to hot labs and do the work themselves; the students get access to the labs and help a technician who does most of the work; the student devises an experiment which is done by a technician (possibly without the student even visiting the lab). To my mind, only the first of these is really acceptable since it is the only one of which is likely to en-thuse a student to remain in actinide science. The others are likely to be de-motivating for the students. How-ever, this first approach will be very demanding for the host institutions.

At graduate student level, summer schools would be excellent but these are really “preaching to the con-verted” and I think it is essential that we raise the profile of actinide science at undergraduate level. The Network has an excellent opportunity to do this since there is international concern over the weakness of education in the sciences relevant to the nuclear fuel cycle and, in many universities, there is actually no member of academic staff available who works in the area. As a result, courses are often quite weak and con-tain little or no practical work. If the network were to provide teaching materials, both information which could form the basis of lectures and also perhaps images of demonstration experiments in electronic format (e.g. DVDs), I suspect there would be demand for these. For example, discussion of the electronic structures of the lanthanides and actinides could be one such topic, and it could include images of, say, different Pu oxidation states and their electronic spectra, then lead on into laser spectroscopy. I believe this is important because, by raising the profile of actinide science in undergraduate courses, we will stimulate interest and compete more effectively with other disciplines for the good students.

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Forschungszentrum Rossendorf (FZR), Institute of Radiochemistry

The Institute for Radiochemistry (IRC) is part of the Forschungszentrum Rossendorf (FZR) that was founded in 1992. FZR is equally funded by the Federal Republic of Germany and the Free-State of Saxony. Other institutes at FZR are Ion-Beam Physics and Materials Research, Bioinorganic and Radiopharmaceutical Chemistry, Nuclear and Hadron Physics, and Safety Research. The Institute of Radiochemistry carries out applied basic research on the fields of radiochemistry and radioecology. The motivation and background of the work are environmental processes relevant for the installation of nuclear waste repositories, for the resi-dues and remediation of uranium mining and milling sites, and for radioactive contaminations caused by nuclear accidents and fallout. To reach tho goal of a basic-level understanding of migration processes and the improvement of respective macroscopic transport predictions, state-of-the-art methods and facilities are available, used in a truly interdisciplinary approach.

New laboratories for working with α-, β-, and γ-activity and the license to handle actinides have been into operation since 1997. All spectroscopic facilities and glove boxes are installed in a controlled area. Time-resolved laser fluorescence and laser-induced photo-acoustic spectroscopy are being used to obtain the ra-dionuclides` solution behaviour and their speciation in environmental matrices at very low concentrations. This equipment can also be utilized for concentration determination in solution (together with conventional UV/Vis-spectroscopy and ICP-MS). With detection times down to the femto-second range many organic ligands can be probed, too. Also facilities for solid phase characterizations are available (XRD, TG, DTA, ICP-MS, α,- β-, and γ-spectroscopy, XAS), with some of them allowing also low-level nuclear radiation measurements. EXAFS (Extended X-Ray Absorption Fine Structure Spectroscopy) studies are performed at the European Synchrotron Radiation Facility (ESRF) in Grenoble/France, where IRC/FZR established a Rossendorf beam-line laboratory to handle radioactive samples (ROBL). These measurements provide pre-cise information on the radionuclide valence and the ligand arrangements in the first and second coordination sphere including bond lengths and strengths, not only in solution but also on solid phases (surface complexa-tion). For investigations of colloids, Field Flow Fractionation techniques and Photon Correlation Spectros-copy is at hand. A well equipped microbiology laboratory supports investigations of actinide interactions with microbes and bio-films. Automated column experiments help to develop and parameterise reactive transport models. A wide variety of geochemical speciation codes and coupled transport models is in use and has successfully been applied to describe the source term development and possible effects of remediation measures at radioactively contaminated sites. Respective thermodynamic databases, also covering sorption equilibria, have been set up.

The institute has been involved in many national and international research co-operations. Within the fourth and fifth EC framework programme, IRC at FZR participated in a variety of projects, concerted actions and thematic networks.

Contribution to ACTINET: “Selection of research areas of broad interest” FZ Rossendorf would like to contribute to the following topics of scope 1 and 2, but there is less interest in topics belonging scope 3:

Scope 1. Chemistry and Physics of Actinides in Solution and Solid Phases

• Aquatic chemistry of actinides and long-lived radionuclides

- Determination of complexation constants and speciation in solution, identification of species stoichiometry and structure by spectroscopic evidence - Investigations of reaction mechanisms, especially for changes in redox state, and their kinetics

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• Actinide-containing mineral phases

- Determination of stoichiometry crystallinity and surface topology (phase characterization) - Thermodynamic solubility parameters - Mineral phase formation reaction paths and kinetics

• Thermodynamics of solid solutions

- Identification of composition ranges and end-member stability - Development and application of thermodynamic models

Scope 2. Chemistry of Actinides in the Geological Environment

• Aquatic chemistry of actinides and long-lived radionuclides (This topic dealing with more general thermodynamic aspects is of course also valid for WG 1)

- Determination of complexation constants and speciation in solution, identification of species stoichiometry and structure by spectroscopic evidence - Investigations of reaction mechanisms, especially for changes in redox state, and their kinetics

• Mineral matrices

- Identification and quantification of mineral reactions and secondary phase formation - Fate of actinides during mineral weathering - Reaction kinetics and reversibility

• Colloids

- Role of inorganic colloids as carriers - Interactions of actinides with complex organics including humics (natural origin and labeled model substances), focused on redox sensitive systems and incorporating competing reactions - Kinetics of colloid formation, colloid stability

• Sorption phenomena

- Stoichiometry and structure of sorbed complexes (including ternary ones with organic compounds up to humics), characterization of reactive surfaces - Application of surface complexation models (SCM) combined with an advanced sorption database and respective modeling tools, evaluation of bottom-up modelling strategies / predictive capabilities - Interactions of sorption, surface precipitation and diffusion - Sorption kinetics

• Interactions of actinides with microbes, bio-films and plants

- Investigation of the interaction of actinides with dominant bacteria found in the environment of se-lected areas (in particular: nuclear waste repositories). - Quantification of actinides and other heavy elements bonded on micro-organisms in dependence of the experimental parameters like pH, gas atmosphere, presence of different ligands. - Spectroscopic characterization of the formed actinide complexes/compounds. - Identification of fundamental processes

Contribution to Work Package 1 “Management structure and a polled system of facilities”

Rossendorf Beamline ROBL

Possible Modes of Measurements:

XANES and EXAFS spectroscopy of radionuclides and non-radioactive samples at ambient and low tem-peratures:

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transmission measurements

Fluorescence measurements for dilute samples

Quick EXAFS for time-dependent studies

Polarized X-ray absorption spectroscopy

X-ray beam characteristics:

The energy range usable at ROBL is 5-35 keV (5-12 keV with Si mirrors, 12-35 keV with Pt mirrors). The photon flux at an energy of 20 keV and a beam current of 200 mA is 6 x 1011 Photons / s.

Installed equipment:

Glove box for handling of radioactive samples

Three remote controlled sample positioners inside the glove box

Optical rail for mounting of detectors

Possibility to position non-radioactive sample outside the glove box

Gas ionization chambers with 310 and 170 mm length

Quad pixel Ge solid state fluorescence detector

Fluorescent x-ray ion chamber detector

Closed cycle He cryostat

Feedback system for beam stabilization

The isotopes to be investigated at ROBL and their half-lives are given below. Additionally listed is the maximum amount of material to remain below the activity limit of 185 MBq (5 mCi).

Isotope

Half-Live (years)

Amount (g)

Isotope Half-Live (years)

Amount (g)

Np-237 2.1 x 106 6.97 Pu-239 2.4 x 104 0.08

Am-241 433 1.4 x 10-3 Pu-242 3.75 x 105 1.27

Am-243 7370 0.025 Ra-226 1600 0.005

Po-208 2.9 8 x 10-6 Tc-99 2.1 x 105 29.1

Po-209 103 3.01 x 10-4 U nat 4.47 x 109 1000

Pa-231 3.28 x 104 0.106 Th nat 1.4 x 1010 1000

All radioactive samples will be delivered, stored, and handled according to the safety regulations agreed upon with the ESRF. This includes placing the samples within a multiple-layer containment, permanent monitoring of radioactivity, and redundant safety systems.

1. Applications directly to the ESRF, deadlines are March and September every year, the proposals are evaluated and selected by the ESRF Advisory Committee, covered costs are running costs at ESRF, travel expenses and accommodation, see the ROBL WWW Site for administrative details.

2. Applications to the EC (ROBL is again applying in the 6th Framework for funding as an EC Large Scale Facility), deadlines are April and October every year, the proposals are evaluated and selected by an interna-tional review committee, covered costs are running costs at ESRF, travel expenses and accommodation

3. Direct scientific co-operation with FZ Rossendorf

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Only specially trained staff will be allowed to operate this experimental station. However, ROBL will offer its know-how in this field to outside collaborators.

Laser Spectroscopy

Time-resolved Laser-Induced Fluorescence Spectroscopy (TRLFS):

Ti-Sapphire Laser (2nd harmonic generation) with Spectrograph and ICCD Camera (Gate > 5 ns; Delay range 5 ns-ms).

Nd:YAG (3rd and 4th harmonic generation) with Spectrograph and ICCD Camera (Gate > 5 ns; Delay range 5 ns-ms)

Diode pumped Nd:YAG (3rd and 4th harmonic generation) with Spectrograph and Intensified Diode Array (Gate > 5 ns; Delay range 5 ns-ms)

Tunable fs-Laser system (cw: Nd:YVO4; Ti-Sapphire oscillator with regenerative and multi-pass amplifier; optical parametrical amplifier (OPA); wavelength range: 280 nm to 10 :m) with Spectrograph and ICCD Camera (Gate 120 ps-6 ns; Delay range 25 ps-20 ns)

Laser-Induced Fluorescence Spectroscopy (LIFS):

Nd:YAG (3rd harmonic generation) in combination with an optical parametrical system (wavelength range 220 nm … 690 nm / 730 nm –1800 nm) with Spectrograph and ICCD Camera (Gate > 5 ns; Delay range 5 ns-ms,static). Reduced availability, Laser is shared with other methods.

Laser-Induced Photoacoustic Spectroscopy (LIPAS):

Nd:YAG (3rd harmonic generation) in combination with an optical parametrical oscillator system (wave-length range 220 nm-690 nm / 730 nm –1800 nm) with equipment for photoacoustic detection of absorbency. Reduced availability, Laser is shared with other methods.

(TR)LFS is possible with all fluorescent aqueous ions and complexes, and with respective solids. In particu-lar this includes Uranium(VI), Curium and Europium, and also organic ligands and fluorescent complexes with lifetimes < 20 ns. LIPAS is currently applicable to non-fluorescent (and fluorescent) ions, complexes and compounds in solution. The following nuclides can be measured:

Thorium: Th-nat, Uranium: U-233, U-nat, Neptunium: Np-237, Np-239

Plutonium: Pu-238, Pu-239, Pu-242, Americium: Am-241, Am-243

Curium: Cm-244, Cm-248

In addition, further isotopes often occurring as impurities accompanying the above nuclides, are permitted to handle, too.

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Ecole des Mines de Nantes, Laboratoire SUBATECH

Description of the resources and activities SUBATECH is a Joint Research Unit (JRU) of the Ecole des Mines de Nantes (ENSTIMN), the IN2P3-CNRS and the University of Nantes. Its mission are basic subatomic physics and associated technologies: environmental radiochemistry and research in high level waste management. SUBATECH has no legal status on its own. SUBATECH is involved as partner in the Network through the two legal entities ARMINES (ARMINES-SUBATECH) and ENSTIMN (ENSTIMN-SUBATECH). ARMINES (Association pour la Re-cherche et de Developpement des Methodes Industriels) offers the laboratories and administration, whereas ENSTIMN (Ecole Nationale Superieur des Techniques Industrielles et des Mines de Nantes) contributes the scientific and technical personnel. Additionally, for European Community Contracts, the ENSTIMN has given his legal, financial and administrative rights to ARMINES, including the right of signature.

The radiochemistry group of SUBATECH will carry out the contribution to the Network of Excellence. The radiochemistry group counts about 25 scientists, engineers and technicians, including actually six Ph.D. stu-dents. The group is involved in various contractual research activities in the field of nuclear waste manage-ment. Many framework contracts exist with the European Commission, with the CEA and with ANDRA (French national nuclear waste management company) in this field. Scientists in the department of radio-chemistry have experience in radiochemistry, geochemistry, microbiology, thermodynamics, and radiolysis. The radiochemistry group operates also a service for measurement of radioactivity in the environment, SMART, who has received the accreditation COFRAC for quality assurance in actinide measurement tech-niques and training of personnel.

The radiochemistry group has about 400 m2 of laboratory space and of disposes of the following equipments and instrumentations to be used to manipulate up to 1 MBq of actinides (exception: 100MBq Ac225):

• 4 low background gamma spectrometers with two sample exchangers

• 1 portable gamma spectrometer

• 1 X-ray spectrometer (low energy X ray emitters)

• 1 X-ray fluorescence spectrometer,

• 2 Proportional counters (type IN20) containing 10 detectors for the counting of alpha(tot), beta(tot),

• 2 alpha spectrometers with 15 measurement cells

• 2 liquid scintillation counters with sample exchangers to measure beta emitters

• 1 ICP-MS with collision chamber

• 2 UV spectrometers

• 1 FTIR spectrometer

• 2 Capillary electrophoreses instruments

• 1 Oxidizer (to allow separation of 14C and 3H)

• 1 Alpha spectrometer for the measurement of Radon-daughters

• 3 Radon measurement units

• 1 Microwave mineralisator

• Potentiometer, coulometer, voltammeter

• 2 Cells fixing electrochemical in situ conditions for EXAFS measurements

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• 5 Inert gas glove boxes

• 1 Other glove box for the manipulation of actinides

• 4 Other glove boxes

The mission of the radiochemistry group is the development of solutions for the management of radioactivity in the environment, in industry and medicine.

The research themes are linked to environmental issues, to the nuclear fuel cycle, to radioelements of medi-cal interest and to the development of analytical techniques. The principal research theme concerns the in-teractions of radioelements in natural water environments, be they either related to radioecological questions at the biosphere /geosphere / hydrosphere interface, or to the environment of the deep geological disposal of radioactive waste. The goal of the research programme is to contribute to radiological safety and to allow assessment/prediction of environmental impacts of radioactive sources both for short and very long periods of time. For this purpose, model development is an integral part of our work. The applied research is well rooted in a long-term oriented fundamental radiochemical research on the chemical properties of radionu-clides and on the effect of radiation on these properties.

In some more detail our research items are summarized as follows:

• In the field of general radiochemistry we study the chemical properties of Tc, Zr, U under controlled atmosphere conditions with and without external irradiation (alpha and gamma) and the co-precipitation behaviour of actinides with UO2. Three PhD thesis have been performed on the properties mainly of Tc(IV).

• In the field of radioecology, specific research items are a) the mechanism and thermodynamics of the interaction of humic substances in surface aquifers and of kerogenes from deep geological formations governing the migration of radioelements, b) the effect of microorganism on the migration of radioele-ments in a reducing geochemical environment, c) the impact of radioactivity on the safety of drinking water, d) the radon.

• In the field of the safety of nuclear waste disposal, specific research items are a) the mechanism of inter-action of nuclear waste glasses and spent fuel and of incorporated radionuclides with groundwater; here we study in particular diffusion processes and the effect of radiolysis, b) the development of mechanistic and thermodynamic models to predict the effect of geochemical parameters (pH, Eh, pCO2…) on the in-teraction of radionuclides (Tc, U, Se, Ni, C, Ac, Zr) with bentonites and ciments as engineered barrier materials and with host rock clay minerals, c) the mechanism of radionuclide transport in nano-porous media: coupling of radiochemistry and hydrodynamics.

• In the field of new reactor concepts the laboratory studies the properties of fuel particles of HTR reactors under conditions of nuclear waste disposal

• In the field of analytical techniques the laboratory concentrates on separation techniques of actinides as well as of pure beta emitters from complex solid and liquid matrices

Description of scientific programmes of actinide science that would both be of prominent sci-entific interest to us • Networking of the formation of young PhD students and engineers in the field of actinide chemistry. The

Ecole des Mines de Nantes is an elite school of engineering, with strong involvement in nuclear fields. Radiochemistry and actinide chemistry are important teaching issues and access to the modern European research infrastructure of the core institutions of the network is very important for the future professional perspectives of the engineering students. Currently also 4 PhD students are working in the field of nu-clear waste management in the radiochemistry department, two of them with actinides. We would be very much interested in a European Master of Nuclear Engineering or a corresponding radiochemistry oriented Master programme

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• The geochemistry and environmental chemistry of the actinides. We are currently working in the envi-ronment related solution chemistry, particularly of the tetravalent actinides as well as in their solubility and solid solution formation. We are also strongly involved in the interface chemistry of the actinide ions, particularly with reference to clay surfaces and organic matter. Our interest is as well in the geo-chemical thermodynamics and kinetics of the actinides: development of respective data bases etc.. The network may help us to perform experiments with larger quantities of Pu in a laboratory, which is better equipped for this work then ours.

• Actinide chemistry and physics related to the performance of high level waste glass and spent nuclear light water reactor fuel in long-term interim storage and final disposal. Here we participate in a project in the 5th framework programme of the European commission with our modelling capacity as well as with experiments in the field of radiolysis effect on fuel dissolution. We are interested to take advantage from the network structure to design experiments with high level waste glass and spent fuel, to help resolve fundamental questions on corrosion mechanism and actinide retention processes. Experiments with real high level waste forms will principally be performed in the laboratories of one of the core institutions of ACTINET, but it would be beneficial both to core institutions and to the other members of the network, if some pertinent experiments can also be designed according to the research strategy of a member or-ganisation.

• Actinide chemistry and physics related to new reactor concepts. We are interested particularly in HTR type reactors. Currently, we participate in two projects of the European commission: performance as-sessment of Thorium or mixed U/Th based fuels kernels as waste form for final disposal. We will ana-lyse the performance of irradiated kernels on the mCi level in our laboratory. Our experience in the co-precipitation of tetravalent actinides from aqueous solutions may also help to design new fuels for novel reactor concepts.

• Analytics of actinide ions in the environment. There is still quite a lot of research necessary to measure actinides at environmental concentration levels in divers matrices. We would like to benefice from the network structure to collaborate in respective research.

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The Belgian Nuclear Research Centre (SCK•CEN)

1. Introduction

The Belgian Nuclear Research Centre SCK•CEN is an institute of public utility under the tutorial of the Bel-gian Federal Minister in charge of energy. More than 600 highly qualified researchers and technicians realize an annual turn-over of 75 million Euros, 50 % being covered by a governmental subsidy and 50 % due to contract work and services for the Belgian and foreign industry and the European Union.

SCK·CEN plays a unique and pivotal part in radioactive waste management and site restoration, in nuclear reactor safety and radiation protection, and in the development of multidisciplinary national and international projects. As a leading research institution, it recognizes its responsibility for advising the Belgian authorities and industry on nuclear matters and for occupying a central position in nuclear science and technology re-search, development, and demonstration activities.

SCK•CEN's most important installations are the reactors BR1, BR2, BR3 and VENUS, hot laboratories and an underground research facility (-225 m) for the study on the disposal of radioactive waste in clay layers. A new accelerator driven neutron source, MYRRHA, is being designed.

SCK•CEN has extensive expertise in radioactivity measurements for nuclear, biological, medical and envi-ronmental applications and in the handling of alpha emitting radionuclides. Its infrastructure includes equip-ment for various types of destructive and non-destructive analyses as well as glove-boxes and hot-cells. The laboratories of the Analyses and Applied Radiochemistry group and the Laboratory for Low-Level Radioac-tivity Measurements are accredited according to the European EN45001 (now ISO 17025) norm. The table in ANNEX 1 gives an overview of destructive and non-destructive analytical techniques that are available at SCK•CEN for application on radioactive materials.

SCK·CEN contributes significantly to nuclear education and training. Let us mention its PhD and postdoc program for hiring about 10 young scientific researchers every year and more recently its role in the Belgian and the European Nuclear Engineering Network. There is furthermore the International School for Radio-logical Protection, the organization of nuclear oriented conferences, symposia, workshops, topical days, lunch talks and training programs, and the Knowledge Centre (former library).

More information about SCK•CEN, its activities, infrastructure and equipment, also with respect to acti-nides, can be found at the SCK•CEN web site: http://www.sckcen.be

2. SCK•CEN, partner for ACTINET SCK•CEN participated as one of the four core members to the CAPITAN EoI. Its programs, skills and tools cover each of the main topics of the scientific scope of the planned Network. Within ACTINET, SCK•CEN can contribute to each of the three working groups for the selection of research subjects of common interest, i.e. chemistry and physics of actinides in solution and solid phases, chemistry of actinides in the geological environment and basic properties and evolution of actinide materials under irradiation. More than 30 perma-nent researchers, several temporary young researchers (PhD candidate or postdoc) and more than 10 research engineers are involved in actinide related work at SCK•CEN. Many of SCK·CEN's major projects include indeed studies on the chemistry and physics of the actinides and an important part of its resources are used and can be pooled in this context. A few examples follow and some of them are discussed in more detail in the next pages.

In the Reactor Safety division, the Fuel Research section of the Reactor Materials Research department, in collaboration with other groups inside and outside SCK·CEN, builds on a tradition of research on high burn-up and MOX fuel at SCK·CEN. Their work centers on the basic properties and evolution of actinide materi-als under irradiation and the chemistry and physics of actinides, mainly in solid phases. The Materials Test Reactor BR-2, a large number of alpha-tight hot-cells and associated neutron physical, solid state and ana-lytical research tools are at their disposal. More information is given in the next part. The same division

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made an important contribution to the ongoing international evaluations of partitioning and transmutation and MYRRHA intends to trigger extra and new R&D in this area as one of its main applications shall be the study of the transmutation of minor actinides and long lived fission products.

In the Radioactive Waste & Cleanup division, the sections R&D Geological Disposal and R&D Waste Pack-ages of the Waste and Disposal department deal with the geochemistry of actinides in the geological envi-ronment. More information is given in the next part. Apart from the HADES Underground Research Facility in the Boom Clay and their own laboratory infrastructure and equipment, they make use of the analytical know-how and equipment within other groups, especially the Nuclear Chemistry and Services department and the Radioprotection division.

Also in the Radioactive Waste & Cleanup division, the physics and chemistry of actinides in solution are part of the work area of the Nuclear Chemistry and Services department and the Site Restoration department. The former has a "plutonium laboratory" and provides analytical and radiochemical services for Belgian nuclear programs, especially nuclear fuel producers. It was e.g. a main contributor to the experimental part of the international ARIANE (Actinide Research in a Nuclear Environment) project. The Chemical Processes sec-tion of the Site Restoration department runs a.o. a project on advanced aqueous reprocessing, including parti-tioning of minor actinides. More information is given in the next part.

In the Radioprotection division, the department Safeguards and Physical Measurements performs research related to accountancy and physical control techniques of fissile and other sensitive materials and a.o. they use advanced neutron and gamma counting for the qualitative and quantitative assay of actinides in radioac-tive waste and in humans. The department Low-Level Radioactivity Measurements has been specializing in the assay of actinides in environmental and biological samples by alpha spectrometry after chemical separa-tion. They have also liquid scintillation counters with alpha discrimination.

3 Reactor Materials Research department, section Fuel Research Introduction

The Fuel Research section is part of the Reactor Materials Research department of SCK•CEN. The activities of the fuel group include fundamental and applied actinides research and the group has theoretical, practical and operational competences relevant for both fundamental and applied actinide research. These compe-tences are coherent with two major infrastructures of our research centre, in particular the Materials Test Reactor BR-2 and the hot laboratory LHMA, which are both located at the Mol site of SCK•CEN. The study of actinides under irradiation requires a combination of neutron physical, solid state and analytical research tools. In paragraph 3.2, a short introduction will be given to two recent research programs that include acti-nide research under irradiation, to more fundamental solid state research on 5f electron behavior and to fuel behavior modeling relevant to irradiation of actinide containing targets and fuels. In paragraph 3.2.1, the experience with handling and investigation of highly radiotoxic and active materials will be outlined. A ta-ble with relevant infrastructure and the limitations for use with actinides is given in paragraph 3.4.

Actinide Research: relevant experience, current projects and future activities

Current MOX research activities (L. Sannen)

Since about three decades SCK•CEN is managing and executing international R&D Programs dedicated to MOX fuel. These programs result in a continuous updating and completion of MOX fuel database mainly devoted to pending licensing questions of plutonium recycling in commercial reactors. Both neutronic and thermo-mechanical validation of MOX fuel is being addressed.

The neutronic validation for reactor physics parameters is performed in the clean conditions of the VENUS critical facility. It focuses on the experimental determination of fission rate distributions, reactivity effects and spectral indices measured in various relevant critical mock up configurations. Appropriate neutron trans-port codes are used to guide and interpret the experiments.

The thermo-mechanical validation concerns complete post-irradiation examinations (PIE) in the hot-laboratory LHMA on fuel behaviour both under normal and off normal irradiation conditions. Normal irra-diation conditions are obtained through large-scale irradiations in various reactors including the SCK•CEN

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research reactor BR2, while off-normal conditions are simulated in BR2. At present the technology to per-form instrumented irradiations is under implementation, i.e. both the re-fabrication & instrumentation of ir-radiated fuel at the hot lab LHMA and instrumented irradiation loops at BR2. All basic PIE equipment for fuel performance evaluation is available at LHMA and strong emphasis is put on solid-state research facili-ties, including X-ray diffraction, scanning electron microscopy, microprobe analysis, transmission electron microscopy and X-ray photoelectron spectroscopy.

Fifth framework program FUTURE (V. Sobolev)

The SCK·CEN is a partner of the project FUTURE (FUel for Transmutation of transURanium Elements). The overall objective of this project is the design and development of a fuel concept for a subcritical accel-erator-driven transmuter of actinides with fast neutron spectrum. Novel uranium-free fuel materials will be investigated. The U-free concept is based on the idea that the omission of uranium will minimize the amount of actinides produced and improves the properties of the fuel or target. The highest priority was given to transuranium oxide based fuel, either as a homogeneous mixed transuranium oxide (Zr,Pu,Am)O2-x, or as a compound where (Pu,Am)O2-x is mixed with a ceramic matrix, such as ZrO2 or MgO. Because of uncertain-ties about these fuel forms, thorium-based fuel (Th,Pu,Am)O2-x should be kept as a back-up solution.

The small batches of these fuels will be fabricated in quantities suitable for measurements of their basic structural, thermal and mechanical properties. The missing properties and their irradiation behaviour will be evaluated at this stage of studies on the basis of modelling.

The feasibility of the different designs will be checked with preliminary thermohydraulic and reactor-physics calculations, leading to a first specification. Special attention will be given to engineering solutions for the expected large helium production, the poor thermal conductivity, and to unfavourable behaviour of these fuels during accident conditions.

In the next phase, more detailed performance analysis will be performed with the fuel performance codes specially extended for these fuels. The safety assessments will be structured along the lines of the defence in depth concept, covering normal operational conditions, transients and accidents.

Fifth framework program OMICO (M. Verwerft)

OMICO compares the behaviour of oxide fuels with homogeneous and heterogeneous microstructure and with three different chemical compositions. It addresses fundamental questions on the mechanisms that gov-ern the release of fission gas. This is to be achieved through the irradiation and in-pile measurement of cen-tre-line temperature and internal pressure of a small bundle of experimental fuel pins. At regular intervals, a non-instrumented sub-assembly will be unloaded and measured non-destructively off-site in the hot lab. The irradiation conditions will be fine-tuned on the basis of concurrent modelling of the fuel behaviour and the comparison of calculated predictions with experimental results of both the in-pile and out-of-pile measure-ments.

The test matrix compares in a systematic way the behaviour of three different fuel compositions (UO2, (U,Pu)O2 and (Th,Pu)O2), and for each composition, two different microstructures are inter-compared (ho-mogeneous and fine dispersed ceramic-in-ceramic). The primary objective is to provide insight in the sepa-rate effects of fuel chemistry (matrix composition) on the one hand and the degree of dispersion of the fissile material (microstructure) on the other hand.

Experimental studies on 5f electron behaviour (S. Van den Berghe)

Basic knowledge in the field of actinide electronic and crystallographic behaviour is required to understand the more technologically important phenomena such as grain boundary physico-chemistry in fuel, fission product migration, etc. Such knowledge can be achieved through separate effects tests and model system engineering, in which the typical 5f-electron behaviour of the actinides is studied.

For several years now, samples of various single-phase uranium compounds (mostly oxides for now) have been prepared and studied with X-ray diffraction at our institute and with neutron diffraction in collaboration with the Institut Laue-Langevin in Grenoble, to unravel their crystallographic structures. Subsequent inves-tigations of these compounds with X-ray Photoelectron Spectroscopy have allowed us to couple this crystal structure to the electronic structure. Transmission Electron Microscopy investigations can then be used to confirm and substantiate this coupling. Collaborations with Lawrence Livermore National Laboratory have

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allowed us to perform XAFS measurements in the past that have further confirmed our findings. It is our intention to eventually incorporate also other actinides in these studies.

Advanced model development (S. Lemehov)

The interest in the transmutation of minor actinides and potential perspectives of urania free fuel composi-tions have raised the need for developing comprehensive mechanistic models for fuel performance codes. Urania free fuel compositions of the concepts currently considered have thermal mechanical and neutronic properties, which differ considerably from that of standard LWR fuels. Fuel performance codes originally developed and verified for UO2 fuel have to be considerably improved and extended in order to cope with new concepts. Studies on actinides have always been limited because of their radioactive properties, which need specific work conditions. Thus mechanistic modelling with fuel performance codes becomes practically important.

At SCK•CEN fuel modelling compares two main directions: development of models for individual fuel properties (such as thermal conductivity, heat generation profile, radial burn-up distributions, isotope in-pile depletion/burning and build-up, etc.) and development of integral fuel performance code capable of predict-ing in-reactor and post-irradiation behaviour of fuel rods. In the frame of this research activity a new model for predicting thermal conductivity of fuels containing minor actinides has been developed and successfully verified on known data sets. The model was incorporated into the full scale fuel performance code MACROS developed at SCK•CEN based on an advanced version of the one-cell neutronic code PLUTON coupled with the thermal mechanical code ASFAD. One of the main practical goals of the MACROS code is to predict in-pile temperatures in the OMICO test fuel pins with respect to actual irradiation conditions (neutron spectrum, properties of moderator, effects of environment) and fuel compositions to be irradiated (homogeneous and heterogeneous oxides). It is our intention to release individual models and the MACROS code for the OECD/NEA database.

Planned actinide research

The actinide research items that will be studied in the Reactor Materials Research department in the near future focus on solid state aspects of actinide oxides, in-reactor behaviour of these compounds and evolution during post-irradiation storage.

Fundamentally oriented, experimental thermophysical research will be conducted on the following subjects:

1. Re-visiting the oxidation mechanisms of UO2, with emphasis on defect structure generation and stability, mainly through combined X-ray, neutron and electron diffraction, combined with surface spectroscopy

2. Correlation of structural and electronic behaviour: 5f electron localization and its influence on structural stability of specific compounds: alkali uranates and alkali earth urinates

3. Re-visiting the plutonium and actinium thermochemistry: phase diagrams, thermodynamic data and crys-tallography, mainly oriented to valence shifts in oxide systems

More applied research will be performed relative to the in-pile performance of actinide doped LWR fuel and ceramic-ceramic, CERCER, mixtures:

• Preliminary design of the experimental fuel pins containing MA (minor actinides) and LLFP (long lived fission products), and modelling of their in-pile behaviour under typical irradiation conditions of MTR (at first stage) and at expected conditions of a prototype reactor-burner.

• In-pile behaviour of experimental targets containing high amounts of americium and plutonium.

Theoretical modelling efforts will be devoted to the thermomechanical modelling of in-pile behaviour of minor actinide containing targets:

• Development of models for prognosis of the thermophysical properties of the fuels containing MA and LLFP, and the database of these properties.

• Modelling the neutronic properties of targets containing high concentrations of minor actinides.

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Training & personnel In the fuel and actinide research field, the Reactor Material Research department has 5 permanent research-ers, 2 temporary (doctorate or post-doc) research positions, 5 research engineers and 4 technicians. The de-partment has a long history of international collaboration and training external personnel on specific research facilities.

Infrastructure Hot laboratory

A review of the European hot laboratories was recently made (Konings 2001) and it shows that no specific regulations pertain to the acceptance of irradiated targets containing minor actinides. In general, it is quoted that the presence of trace amounts of the minor actinides "as present in irradiated nuclear fuel" is accepted in the fuel hot cells. Limits on the amount of fuel that can be present in the hot-cells are based on gamma dose rate and potential criticality.

For minor actinide handling, specific problems may arise with respect to neutron dose rate and radiotoxicity. The beta/gamma shielding of hot-cells that are currently in use for research on nuclear fuel obviously is suf-ficient regarding the gamma activity of targets containing high concentrations of the minor actinides. The leak tightness of the shielding may be problematic for some hot laboratories, especially with regard to the acceptance of targets that are damaged. When calculating the radiotoxicity of Pu, Am and Cm and express-ing the annual limit of intake (ALI) as a function of weight, one finds that the ALI of Americium is of the same order as that of Plutonium while for Curium the ALI is two orders of magnitude lower. In view of the high radiotoxicity of the considered isotopes, it will be imperative to have leak-tight hot-cells in which irra-diated targets containing high amounts of Am and Cm are to be handled and/or investigated. There are, at present, several hot-laboratories that do have some hot-cells equipped with inner glove boxes, but due to its long history of MOX fuel research, SCK•CEN has all of its fuel handling hot cells equipped with leak tight inner glove boxes.

Materials testing reactor BR-2

The BR-2 is a high flux engineering test reactor, which differs from comparable materials test reactors (MTR's) by its specific core array. The core is composed of hexagonal Be blocks with central channels. These channels form a twisted hyperboloidal bundle and hence are close together at the mid-plane but more apart at the lower and upper ends. With this array, a high fuel density is achieved in the middle part of the vessel (reactor core with a fuelled height of 760 mm) while leaving enough space at the extremities for easy access to the channel openings. In the BR-2 reactor it is possible to irradiate fissile and structural materials intended for reactors of several types. The current operating regime of the BR-2 reactor is based on five cy-cles of 21 days per year (i.e. approximately 105 effective full power days).

The use in BR-2 of highly enriched fuel elements with high density and incorporated burnable poison allows the acceptance of a considerable amount of negative reactivity caused by strongly neutron absorbing experi-ments.

4 Waste and Disposal department: sections R&D Geological Disposal and R&D Waste Packages Relevant activities of the department Waste and Disposal in the ACTINET/CAPITAN Network of Ex-cellence

Two sections (R&D Geological Disposal and R&D Waste Packages) of the Waste and Disposal department deal with relevant activities within the network. There are skills and tools mainly related to the topic: Chem-istry of actinides in the geological environment.

The section R&D Geological Disposal focuses mostly on the migration behaviour of radionuclides in the geological environment with emphasis on transport processes (diffusion, advection, colloids) and retarda-tion/retention processes (sorption, precipitation, complexation). Their studies are strongly driven by per-formance assessment:

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• RN (radionuclides) migration experiments in Boom Clay and other porous media (lab and in-situ). RN: C, I, HTO, Sr, Ca, Na, Cs, Zr, Ra, Tc, Se, U, Np, Pu, Am, Eu, Pa, Si.

• Effect of NOM (natural organic matter) on the migration behaviour of Se, Am, Pu, Np and U (solubility, complexation, sorption, diffusion).

• Characterisation of NOM in Boom clay.

• Effect of chemically disturbed zones on RN behaviour: alkaline front, NaNO3, oxidation…

• Natural evidence on long-term behaviour of trace elements and RN in Boom Clay.

The section R&D Waste Packages focuses mainly on the leaching behaviour, solubility, sorption and speci-ation of radionuclides like Np, Tc, Pu, Am, U from nuclear waste matrices.

• Leaching behaviour of Np and Tc from doped glass samples.

• Dissolution behaviour of U from simulated spent nuclear fuel.

• Effect of cellulose degradation products on the sorption of Pu and Am in Boom Clay.

• Radiolytic degradation of bitumen and bituminised waste products (associated to solubility and sorption tests studies with Pu and Am).

Available staff

The sections R&D Geological Disposal and R&D Waste Packages of the Waste and Disposal department have 16 permanent researchers, 1 temporary young researcher, 2 research engineers and 9 technicians, 5 of which are trained to work with radioactive materials. The Waste and Disposal department has a tradition of international collaboration, evaluation and dissemination of knowledge and participation in training and edu-cation efforts.

Modelling capabilities

• Geochemical modelling: Geochemical Workbench, PHREEQ/C …

• Transport modelling: Porflow, Xt, Hydrus1D/2D, MODFLOW, own developed codes for the fitting of migration experiments…

• Coupled geochemical transport modelling: GWB-Xt, Hydrus1D-PHREEQ/C

• THM modelling

• Monte Carlo simulations (glass dissolution)

Laboratory infrastructure

1. Activity levels that can be handled in our labs

Radiotoxicity Examples of RN under study

Surveyed Zone (yel-low)

Controlled Zone (red)

A – Very High 226Ra, 237Np, 238Pu, 241Am, 244Cm

400 kBq-400 MBq 400 MBq and more

B – High 45Ca, 85Sr, 131I, 152Eu, 232/233U

4 MBq-4 GBq 4 GBq and more

C – Medium 22Na, 75Se, 95Zr, 99Tc, 137Cs

40 MBq-40 GBq 40 GBq and more

D – Low 3H, 7Be, 14C 400 MBq-400 GBq 400 GBq and more

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2. Glove boxes (10)

• Alpha boxes (controlled zone):

• 3 with anaerobic controlled atmosphere: Ar/CO2

• 2 with inert atmosphere: Ar

• 1 with Air + (H2)

• Other glove boxes (surveyed zone):

• 2 with anaerobic controlled atmosphere: Ar/H2/CO2 and Ar/CO2

• 2 with inert atmosphere: Ar/H2 and N2

•

3. HADES Underground Research Facility (-222 m depth, 200 m long) in the Boom Clay.

Permission to use RN in experiments such as corrosion, migration, radiation. Some examples:

• EC-CORALUS: Corrosion tests on alpha-doped HLW glasses (237Np, 238/242Pu, 241Am, up to 100

GBq/isotope).

• EC-TRANCOM-CLAY: migration test with 241Am-14C-double labeled Natural Organic Matter (~155 MBq)

• EC-CERBERUS: 99Tc and 241Am migration tests in heat and radiation (444 TBq 60Co) affected Boom Clay.

• Other RN used: HTO, I-125, 152/154Eu, 85Sr, 134Cs, 233U, H14CO3-

The HADES underground lab has an extremely low background radiation and therefore it is used by JRC-IRMM for ultra low level gamma spectroscopy and by SCK•CEN for low level beta measure-ments.

4. Three thermostated rooms for long-term migration experiments on porous, saturated media (Boom Clay, Yper Clay, bentonite based backfill materials, Opalinus Clay).

• Migration tests under a hydraulic pressure (percolation), electrical field (electromigration), pure dif-fusion tests (e.g. through diffusion).

• Percolation type migration experiments under constant consolidation pressure (oedometers) and mi-gration experiments in isostatic cells.

5. Batch reactors (1 dm³) for reactions under controlled gas atmosphere, continuous logging of pH, Eh, controlled redox (potentiostat) to perform experiments in liquid phase, which mimic in situ conditions (Eh, pH, pCO2).

6. Tools and facilities to prepare doped glass samples.

7. Tools and facilities to pre-treated samples from different waste forms (glass, cement, bitumen, spent fuel...) for further analysis and characterization.

8. As a possible future investment we aim at building a glove-box facility equipped with specific tools for handling geological samples of all kinds, for the preparation of migration experiments and treatment of these cores after the experiment, under a controlled gas atmosphere close to in-situ geochemical condi-tions. This too can be made available to the community as a “user facility”.

Analytical equipment

• UV-VIS spectroscopy

• Liquid scintillation counter for beta and alpha activity measurements

• NaI gamma counter for gamma activity measurements

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• Total inorganic and organic carbon analyzer

• Gel permeation chromatography (separation NOM)

• Potentiostat (electroreduction and controlled Eh)

• Experimental set-up to measure Eh and pH in-situ (ORPHEUS)

• BET (N2 adsorption for specific surface area measurements on powders)

• Luminimeter (measurement of radiolytic products)

• Furthermore the radiochemical and analytical skills and tools of the Nuclear Chemistry and Services department are heavily relied on.

Scientific topics

We agree with the geochemical topics defined by FZK-INE (already well discussed in the FUNMIG pro-posal).

• Aquatic chemistry and thermodynamics of actinides.

• Interaction of actinides with mineral surfaces.

• Formation of secondary phases.

• Mechanism of spent fuel and glass corrosion.

• Role of organic and inorganic colloids (we would not call it colloid facilitated transport…).

• Reactive transport of actinides in the geosphere.

• Experiments: lab versus field

• Reactive transport modelling – development of concepts

• Applicability of laboratory results to natural systems.

• Development/improvement of speciation tools/methods either direct or indirect.

• Role of micro-organisms

5 Nuclear Chemistry and Services department and Site Restoration department The relevant activities of the Nuclear Chemistry and Services department and of the Chemical Processes section of the Site Restoration department are mainly related to the topic: Chemistry and physics of actinides in solution (and solid phases).

Nuclear Chemistry and Services department

The mission statement of the Nuclear Chemistry and Services department has been redefined as "To be an advanced radio-chemical laboratory for Belgium and the European Union", in accordance with the law and with the Corporate Charter of SCK·CEN.

The objectives are:

• to provide radiochemical services for Belgian nuclear programs, where and as required,

• to perform appropriate R&D anticipating future customers' needs in measurement services.

To reach these objectives, the Nuclear Chemistry and Services department maintains and regularly updates a large panel of analytical instruments allowing traces analyses, characterisation of the main components of several inorganic materials, isotopic analysis and radiochemical measurements.

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Most of the routine analyses performed for external and internal customers are resumed within the scope of our Quality Assurance system according to the EN45001 (now ISO 17025) norm and have been granted a certificate of BELTEST since 1996.

Besides those specific methods, the other activities of the service are governed in line with the same QA-principles.

The laboratory offers a broad choice of analytical techniques virtually allowing a complete chemical and radiochemical characterisation of materials.

• Major and minor components, as well as trace elements are measured in solutions by inductively coupled plasma mass spectrometry (ICP/MS). The nuclearised version coupled with a glove-box allows the analysis of alpha contaminated samples.

• The isotopic composition of elements is determined by thermal ionisation mass spectrometry (TI/MS) or by ICP/MS.

• The qualitative and quantitative analysis of a wide range of alpha, beta, and gamma emitting radionu-clides is performed using alpha and gamma spectrometry and liquid scintillation counting.

• Impurities, down to the µg/g level, are determined by spark source mass spectrometry (SSMS) or by optical emission spectrometry. These techniques are fitted for glove-box applications on hazardous mate-rials like solid nuclear fuels.

• The anion composition is measured by ion chromatography in glove-box.

The laboratory is involved in most of the research programs running at SCK•CEN. Besides the classical destructive burn up measurements more extensive studies have been conducted on high burn up UO2 and MOX for the determination of higher actinides and fission products (ARIANE project). This project im-proved the knowledge of the inventories of actinides and fission products in UO2 and MOX fuels, irradiated at various burn up for both PWRs and BWRs. A extension of this work for fuels of still higher burn up is being negotiated (MALIBU project).

Other projects like Waste and Disposal resort to the laboratory for measurements related to the migration studies of actinides and fission products in the clay host rock, while Radioecology asks for low level meas-urements of actinides in soil and plants extracts.

Site Restoration department: Chemical Processes section

The objectives of the Chemical Processes section are:

• to study and develop chemical processes that are necessary or useful for nuclear applications,

• to valorize the related know-how by advising, licensing or exploiting these processes for internal or ex-ternal clients.

Most of the work within this section concerns fresh or irradiated nuclear fuel and it relies heavily on SCK•CEN's existing infrastructure (radiochemical labs, alpha glove boxes, alpha hot cells) and alpha-compatible analytical tools.

The group is recovering fissile material from waste, in order to minimize waste costs and to maximize recy-cling of nuclear material. The main application concerns the recovery of fissile material from fresh-fuel solu-tions.

Under contract the group is collaborating on the development and testing of an advanced aqueous reprocess-ing and partitioning process that is based on ion exchange and extraction chromatography together with elec-trolytic reduction.

Studies concerning the electrochemistry of some actinides in aqueous solution are planned for the near fu-ture.

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http://beltest.fgov.be/


Available staff

The available staff within the Nuclear Chemistry and Services department and the Chemical Processes sec-tion of the Site Restoration department comprises 6 permanent researchers, 1 young temporary researcher (PhD candidate), 4 research engineers and 15 technicians, which are all trained to handle radioactive materi-als

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Centro de Investigaciones Energéticas, Medioambientales

y Tecnológicas (CIEMAT)

Introduction CIEMAT as National Research Centre for Energy, Environment and Technology is involved in the development of scientific and technical activities for finding solutions for the improvement of the use of resources and energy generation systems, for the development of alternative energy sources and for solving the problems of the Spanish companies regarding energy and its effects on the environment. Consequently, CIEMAT have facilities, instrumentation and human teams for covering a huge spec-trum of scientific and technological topics.

Human and material resources are distributed in an Internal Structure composed by several Scientific & Technological Departments and Administrative Departments. Nevertheless, materials resources can be considered as centralised resources when adequate.

In the field of actinides, at the moment, two departments are involved:

• The Fission Nuclear Department, mainly focused in the aspects connected with the scientific and technological aspects of the spent fuel itself and its reprocessing.

• The Environmental Impact of Energy Department focused in the interaction between radionu-clides and the geological medium and the subsequent radiological impact.

The proposal for the contribution of CIEMAT to ACTINET is summarised as follows. This proposal has been drawn up taking into consideration the background of CIMAT´s staff in the field of actinides, the R&D national programs on radioactive waste management and the agreements already signed and foreseen by CIEMAT up to now, but also the existing and possible new facilities, really limited at CIEMAT site from the point of view of the radioactivity that could be accepted for handling. Never-theless, the involvement of CIEMAT in new topics in the field is it possible in the near future.

Scientific program Nowadays, CIEMAT try to joint the ACTINET Project by collaboration both on theoretical / bibliog-raphy and experimental work connected with all scope as presented at the workshop held in Karlsruhe on 11/12 December 2002. Specific tasks proposed by CIEMAT are the following.

Scope 1: Chemistry and physic of actinides in solution and solid phases

Chemistry in solution

Study of the extraction properties of new selected molecules synthesised by organic laboratories. The main objective to find molecules that could be useful for the partitioning of actinides in real conditions existing in liquids streams arise at the industrial PUREX process (HAR and HAR). So that 2 / 4 M nitric acidity media and the present of the other elements as lanthanides, fission products, activation products, etc. are the main importance for the study. Besides others conditions as foreseen scrubbing and stripping conditions of the actinides and extra conditions (high and very low acidity) would be taken into consideration.

Data from previous task would be used for design and synthesis of new molecules and for the model-ling and determination of some thermodynamic aspects of complex formed between the organic mole-cule and the actinide cations such as stoichiometry of the complex, structure, etc..

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Development of radioanalytical procedures for identification and quantification of actinides in differ-ent matrices.

Study of the organic compounds used for the formation of complex in strong acidic condition and high-integrated gamma doses due to influence of this aspects in real extraction process and analytical procedures.

Chemistry in solid phases

• Solid-liquid phase equilibrium: Secondary phases formation, solubility studies, and studies of formation of potential protective layers. Studies will be focussed on influence of environ-mental parameters groundwater chemistry, redox potential and container material on long lived radionuclides (Tc, Np, Am) chemistry under near field conditions.

• Kinetic and thermodynamic modelling approach of secondary phases formation.

• Characterization by XRD of alloys formed in non-aqueous media: separation by electrochemi-cal techniques of Res and actinides in molten salts.

Scope 2: Chemistry of actinides in the geological environment

Contribution will be focused on the interaction of actinides with mineral surfaces.

The reaction of actinides and fission products with the mineral surfaces has an important contribution in the regulation of the concentration in the pore water and the retardation in the transport of those radionuclides through the different barriers of a deep geological repository.

The final objective of the research line that CIEMAT (DIAE-CHE) is developing within the projects ACTAF, CRR, FISQUIA, FEBEX, etc is to know the sorption mechanisms and validate the surface complexation models for the principal sorbing minerals in the barriers, and also to quantify the effec-tive surface of these mineral components as a function of the 3D distribution of the porosity, in order to extrapolate the laboratory results to the real conditions of the different barriers.

According to this plan, we are interested to participate and perform the following experimental stud-ies:

• Am and Se sorption on magnetite, since this mineral is one of the principal components of the corrosion products in a reducing environment of the C steel containers and there are few stud-ies and basic data about it. Model validation of surface complexation.

• Pu, Am and Se sorption on calcium and sodium smectite, since smectite is the main compo-nent of the clay barrier and responsible for its thermal, hydraulic, mechanical and geochemical characteristics. Validation of surface complexation. Extrapolation of results and sorption modelling under the clay barrier conditions (geochemistry, density, porosity, etc).

• Pu, Am and Se diffusion in the clay barrier. Determination of the effective porosity and ap-parent diffusion as a function of the density. Congruent analysis with the sorption results.

• The physico-chemical characteristics and ionic strength of the pore water in the clay barrier create instability of the colloids generated within the barrier and are filtered by the same bar-rier. However, in the interface with the host rock (EDZ) stable bentonite colloids are pro-duced in the granite water. These colloids can function as transport vehicles for actinides and fission products. The continuation of the evaluation of the implied processes and the model-ling of this type of transport, which is poorly known at present, is considered worth studying.

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Scope 3: Basic properties and evolution of actinide materials under irradiation

The utilisation of pooled facilities under a common research frame or under bilateral research collabo-ration agreements could be of interest. In particular, activities related to the effect of burn-up, fuel type, and M/O ratio on radionuclides distribution and the consequent on matrix stability and radionu-clides release

Resources Personnel

• Five Doctors and University Degrees with high experience (more than ten years) on waste man-agement, radiological characterization and liquid-liquid extraction for topics connected with hy-drometallurgical partitioning and radiological analysis. Partial time.

• This team works in co-operation with other external Spanish teams for activities connected with synthesis of organic compounds and modelling.

• Three PhD and University degrees with more than 10 years expertise in spent fuel research under repository conditions. Preliminary estimation of human resources in Activities 2.1.2 and 2.3 will be of 0.7 scientist 100% dedicated for a 3-4 years period, starting date 2004.

• Two PhD degrees with an experience of more than 5 years in transport of radionuclides through the different barriers of a deep geological repository.

Laboratories and Significant Instrumentation

Ciemat as member of the ACTINET could contribute with the following material resources for sharing in the framework of NoE:

• Radiochemical laboratories (Installation IR-15) commissioned for working with small amounts of radioactive materials (up to 2x12 GBq of beta-gamma emitters, 2x12 MBq of alpha emitters and 2x30 MBq of uranium. In the future new laboratories are foreseen for working with larger amounts of alpha emitters in additional glove boxes.

• Radiochemical laboratories for migration studies (Installation IR-08) commissioned for working with small amounts of materials containing alpha, beta and/or gamma emitters (specific limits for a big amount of radionuclides).

• Several modern systems and adequate procedures for the identification and quantification of Gamma emitters (including Low Gamma Energy), Pure Beta emitters, Alpha emitters and X-ray emitters.

• 2 Gamma Scanning Assays (hardware and software could modify as adequate and new systems are foreseen).

• NAYADE irradiation facility. Pool type commissioned for working with Co-60 sources up to 16.800 Ci.

• Facilities for the management of radioactive waste generated at others CIEMAT facilities (Instal-lations IR-17 and IR-27)

• Instrumentation commissioned for working with small amounts of radioactive materials as:

- ICP-MS coupled with a HPLC (Laboratory IR-30b) - XRD (Laboratoru IR-09) - Ion Chromatograph - Control area with chemical laboratories commissioned to work with small quantities of alfa (10 MBq) and beta–gamma (30 MBq) isotopes in aqueous and non-aqueous media. This laboratory is equipped to work under anoxic conditions and also in corrosive atmospheres as chloride molten salts (Laboratory IR-30a).,

• Non-radioactive geochemical laboratories

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• Chemical and solid phases characterization laboratories with modern analytical instrumentation (non commissioned for working with radioactive materials), including instrumentation as TG-DSC, Surface area determination by BET method, Laser diffractometer for particle size distribution, ICP-AES, ICP-MS etc.

• Modern informatics and supercomputing systems including the following equipment: SGI Origin 3000, CRAY-J90 and CRAY-T3E.

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UNIVERSITAT POLITÈCNICA DE CATALUNYA (UPC)

Research Team Prof. Dr. Joan de Pablo, Prof. Dr. Jordi Bruno, Dr. Ignasi Casas, Dr. Javier Giménez, Dr. Vicente Mar-tí, Dr. Miquel Rovira, Dr. Josep Torras, Dr. Jordi Vázquez, Mr. Frederic Clarens, Ms. Mireia Grivé and Mr. Ferran Seco.

Scientific Collaborators (Enviros-Spain): Dr. Lara Duro, Dr. Esther Cera, Dr. Cristina Domènech and Dr. Juan Merino.

Facilities • Atomic Force Microscopy (AFM)

• Environmental Scanning Electron Microscopy (ESEM)

• Inductively Coupled Plasma Mass Spectroscopy (ICP-MS)

• Scanning Electron Microscopy coupled with Energy Dispersive Analysis through X-ray spectros-copy (SEM-EDAX)

• Laser Spectroscopy

• Transmission Electron Microscopy (TEM)

• X-ray Photoelectron Spectroscopy (XPS)

• Users of the ROBL (ROssendorf BeamLine) at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France

Activities Interaction of actinides with mineral surfaces and formation of secondary phases

The consortium UPC-CTM-Enviros has been involved in several research activities concerning the study of the interactions between actinides and fission products and solid surfaces of special relevance for radioactive waste management. Among them, the following can be mentioned:

• Study of the sorption of U(VI) onto the surface of canister corrosion products and backfill ad-ditives - U(VI)-FeOOH(am) - U(VI)-Fe3O4(s) - U(VI)-(Fe)olivine

• Study of FP onto bentonite surfaces - Sr-montmorillonite - Cs-montmorillonite

• Study of the sorption of lanthanides onto hydroxoapatite surface

• Study of the sorption of Cs and Nb onto poorly cemented sandstones from Krasnoyarsk-26

The experimental methodology is a combination of solution chemical studies, batch and column, together with surface spectroscopic techniques (EXAFS, XANES, XPS, AFM,…)

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Spent nuclear fuel behaviour under repository conditions

Experimental and modelling studies of the dissolution behaviour of the UO2 spent fuel matrix, in-cluding:

• The bicarbonate promoted oxidative dissolution of UO2 by oxygen

• The bicarbonate promoted oxidative dissolution of UO2 by hydrogen peroxide

• The proton promoted oxidative dissolution of UO2 by oxygen

• The chloride promoted oxidative dissolution of UO2 by oxygen.

• The kinetics and thermodynamics of uraninite dissolution.

Experimental and modelling studies of the thermodynamics and kinetics of uranium secondary phases, specifically: Uranophane, Soddyite, Becquerelite, Schoepite.

These studies have been performed by a combination of solution chemical techniques, including batch and flow-through experiments together with solid spectroscopy and solid surface analyses.

Application of laboratory results to natural systems including colloidal transport modelling, ther-modynamic data bases development

The consortium has been very active in transferring results from laboratory investigations into field and NA studies and vice versa. In particular what concerns the modelling of trace element migration in different NA situations as well as development and application of models for the col-loidal facilitated transport of radionuclides. For instance:

• Trace element modelling in several NA sites, Poços de Caldas, Cigar Lake, El Berrocal, Pal-mottu, Oklo, Mina Fe…

• Testing and development of reactive transport models within the CRR project at the Grimsel Test Site.

In addition, there has been an extensive effort in the development and implementation of thermo-dynamic data bases as a critical component of the geochemical modelling activities.

Participation in projects and related activities • Chemical reaction of fabricated and high burn-up spent UO2 fuel with saline brines (European

Commission) (2) • Source Term for performance assessment of spent fuel as a waste form(European Commission)

(2) • OKLO Natural Analogue: Phase II Behavior of nuclear reaction products in a natural analogue (2,

3) • Transport of radionuclides in a natural system at Palmottu (2, 3) • Aquatic chemistry and thermodynamics of actinides and fission products relevant to nuclear waste

disposal, ACTAF (European Commission) (1) • Spent Fuel Stability under Repository conditions, SFS (European Commission) (2) • Building confidence in deep disposal: the borehole injection sites at Tosmk-7 and Krasnoyarsk-26,

BORIS (European Commission) (1) • The Role of iron corrosion products in the near-field of a HLNW repository (SKB) (1) • Geochemical Barriers for HLRW Repositories. Investigation of the Olivine-Rock Water Interac-

tion (STUK) (2)

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• Development and application of conceptual and numerical models for the trace element transport in natural and anthropogenic systems, Spanish Ministry of science and technology (1, 3)

• Colloid and Radionuclide Retardation Project (Enresa)

Scientific program of actinide sciences • Molecular modelling applied to interaction of actinides, fission products and mineral surfaces • Studies of the transition from actinide polynuclear complexes to colloid formation • Mechanisms and rates of radiolytic product generation at the spent fuel water interface • Experimental and theoretical approaches for the establishment of the temperature effect on ther-

modynamic stability of tetravalent actinides aqueous complexes in the range 25-90ºC • Thermodynamic and kinetic modelling of chemical separation data related to partitioning proc-

esses.

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Institut de Recherches Subatomiques (IReS) /CNRS-IN2P3

Groupe de Chimie Nucléaire, Strasbourg

The Strasbourg group cannot be included in the pooled system of facilities, owing to the very limited number of permanent staff available but is willing to participate in the network as a « pooled facilities user ».

Personnel: 7 researchers (including those from the University), 3 engineers, 1 technician, 1 secretary

Resources • Glove boxes under inert or controlled (CO2) atmosphere for U or Th experiments : 6 • Glove boxes under inert atmosphere for other radioactive elements : 4 These glove boxes

are in a dedicated building which is devoted to the handling of radioactive elements such as Np, Cm or Pu (storage limited to 7.4 GBq all together for Group 1 radionuclides, i.e. highly radiotoxic ones). This building is equipped with a hand-feet detector at the entrance, air-filters and is under depression.

• Low-background α chamber (α analyst, Canberra, 6 chambers, pips detectors) • β-α counting chamber (Eurysis Mesure, Pegasus type) • Liquid scintillation (Quantulus – very low background- and Winspectral, Perkin Elmer) • γ-spectromerter (Ge detector) • Quadrupole ICPMS (Agilent 7500I), to be coupled with an HPLC device (Dionex Agilent

Technology) • Time-resolved laser induced fluorescence spectroscopy for uranium (through excitation at

355 or 266 nm) or lanthanides (mostly europium, through antenna excitation at 266 nm) • UV-visible spectrophotometer (190 – 900 nm) • Freeze-thaw technique • Ultra-centrifugation • Climatic temperature controlling system, CO2-controlled atmosphere available (Vötsch,

VT4004) • Separation on ionic-exchange resins or extraction resins (low level activities) • Electroplating facilities • Alkaline fusion device (Fluxer M4, Analab) • Positron annihilation techniques (Doppler and lifetime spectroscopy)

Radiochemical activities There are two fundamental research axes: actinide/lanthanide solution chemistry and sorption studies.

Solution chemistry: interests are focussed on the effect of very high ionic strength onto equilibrium constants, complexation studies with inorganic ligands, structure of the solvation sphere.. Solvents of interest are water and Room-Temperature Ionic Liquids (RTILs). Whenever possible, collaborations with theoreticians are developed. Extraction studies for actinides and lanthanides are a new aspect to be developed in the future.

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Sorption studies: effect of solution complexation onto the nature of the sorbed species. Determination of the nature of the sorbed species by cross-check of the information obtained by various techniques: XPS, EXAFS, fluorescence spectroscopy...

Scientific program to be incorporated within the network structure The Strasbourg group is very interested in the possibility of handling highly radioactive materials in rather large quantities within the dedicated structure of the network. In this frame, solution chemistry of actinides (Am, Np Cm and Pu) in various room-temperature ionic liquids through UV-Visible spec-troscopy, electrochemistry, EXAFS and, whenever possible, laser-induced fluorescence spectroscopy is expected. Comparison with aqueous chemistry and molten salts chemistry is highly desirable

.

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Institut de Physique Nucléaire, Radiochemistry group ,Orsay

The research topics of the radiochemistry group of the Nuclear Physic Institute in Orsay concern the physico-chemical properties of actinides, transactinides and some others radionuclides such as long-lived fission products present in the fuel cycle. The different fields, which are investigated in our labo-ratory, are the following:

• Speciation and thermodynamics properties of radionuclides in aqueous media.

• Chemistry of actinides in solid phases (synthesis, characterization, dissolution).

• Physico-chemical properties of actinides at the interface mineral/solution.

Chemistry of actinides (An), lanthanides (Ln) and long-lived fission products (LLFP) in aqueous solutions (B. Fourest, C. Cannes) The studies undertaken in this frame, for at least the next three years, have the following main objec-tives:

1. To optimise the dissolution and separation processes of An, Ln and LLFP in the nuclear fuel re-processing cycle. The interest is presently focused on the electrochemical dissolution of uranium car-bide and ternary carbides in different electrolytes, containing or not complexing agents. The kinetics of the dissolution, as well as the parameters of the involved reactions will be determined by using volt-ammetry and potentiostatic electrolysis, with devices set up in “hot laboratory”.

2. To have a better knowledge of the chemical and thermodynamic properties of the above-cited ele-ments. This theme includes both the determination of stability constants of An and LLFP (Se, Pd, Mo, Tc,) and the speciation of these elements under specific conditions (environment, PUREX process, ). Methods relevant of microchemistry, such as capillary electrophoresis, or radiochemistry, such as capillary diffusion (open-end capillary method) have been recently developed for these purposes. The former one will be applied to the UO2

2+/MOxn- (M = I, Se, Re…) or UO2

2+/carboxylic acids systems and to the quantitative determination of mixtures of LLFP in concentrated HNO3 solutions. The latter one will be used to investigate the hydrolysis or the complex formation of actinides at tracer scale amounts. These transport methods have shown to be complementary of very sensitive methods, also developed in the laboratory, such as TRLIFS for fluorescent ions (UO2

2+), or stripping voltammetry.

Solution chemistry at tracer scale (C. Le Naour, D. Trubert) At the moment, research activities of this team are mainly focused on protactinium chemistry in aque-ous solution. Hydrolysis constants of Pa(V) were already determined as a function of ionic strength and temperature. Extrapolation to zero ionic strength was conducted (SIT and Pitzer modelling) and the standard thermodynamic data were determined. Studies of the behaviour of Pa(V) in alkaline me-dia is currently running in order to characterize the equilibrium involving the protactinate ion and to determine the related thermodynamic constant. In the future, thermodynamics of complexation of Pa(V) with chloride, sulphate, carbonate and “humic” substances will be investigated.

Skills: Solution chemistry at atom and tracer scale (chemical isolation of radionuclides, ion exchange and solvent extraction techniques, on line and off line nuclear chemistry) – Medium and temperature effects on thermodynamic data - Sources and targets realization.

Equipments: Hot lab (glove boxes, alpha, beta detectors).

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Chemistry of actinides in solid matrix (N. Dacheux, A. Ozgümüs, M. Genet, S. Hubert) The research activities concern the synthesis, the characterization and the physico-chemical properties of actinide phosphate and dioxide ceramics for the immobilization of actinides, or for long term behaviour of solid Th-based fuel with regard to geological disposal. Samples of thorium phosphate diphosphate (pure or containing large amount of tetravalent actinides) have been synthesized, and the kinetic and thermodynamic aspects of the dissolution have been studied. This ceramic exhibits good retention properties for immobilizing Pu, or other An(IV). In the next 3 or 4 years, we investigate the incorporation of neutron absorbers such as Gd ions in the matrix, and the effect of irradiation (internal by loading with 238Pu, or external with a particles irradiation) on the structure, and the leaching per-formance. The synthesis and the leaching behaviour of other ceramics such as TPD/Monazite based composite, britholite, containing actinides will be studied.

More recently the physico-chemical properties of powdered ThO2, and actinide mixed oxides (Th,U)O2, and (Th,Pu)O2 was also undertaken. The effect of the change of oxidation state of some actinides from the solid solution, in contact with solutions in various redox conditions on the dissolu-tion mechanism is particularly studied in order to provide dissolution kinetics and thermodynamic data. Several studies will be conducted in the future in both fields. The local structure of the solid solu-tions before and after leaching is also under study by XAS. Other mixed dioxides such as (Th, Np)O2 will be also considered.

Equipments :

• BET method (N2) for the specific surface area measurement (U, Th)

• XRD: equipped with Göbel mirror for analyzing the surface layer of rough sample, and tempera-ture chamber for studies of the evolution of crystallographic structures with temperature (2003). This diffractometer allows the analysis of Th and U samples. We expect in the next 3 years the analysis of other actinides.

• Leaching experiments in glove box under controlled atmosphere, or in hot cell.

• Hydraulic press for sintered pellet (U, Th)

• Granulometer (U, Th)

• Photon electron Rejecting Alpha Liquid Scintillation Spectrometry (PERALS) for the actinides analysis at the trace level.

Mechanistic studies of the interactions between actinides and minerals (E. Simoni, R. Drot) Our research activities are focused on both thermodynamic and structural studies of the interactions between actinides and minerals. These studies involve the transfers of chemical species between an aqueous solution and a mineral phase, which are mainly sorption/desorption/precipitation. Since many years, we are performing experiments at molecular level in order to give direct evidence of the sorp-tion mechanisms and use the obtained structural results as an experimental constraint in the modelling procedure.

Our methodology is the following:

• The substrate is characterized by X-ray powder diffraction, infrared spectroscopy and electron probe microanalysis (EPMA).

• Morphology, grain size distribution and specific surface area are determined.

• Determination of the hydration time of a solid in suspension in an aqueous solution - The varia-tion of the solid surface charge is determined by electrophoretic measurements.

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• The acidity constant values are determined from potentiometric titrations of the surface sites that gives the pH at the zero point charge and the surface site density as well.

• Sorption isotherms are carried out.

• In order to experimentally define the sorption equilibria, structural identification of the surface sorption sites and complexes resulting from the metal sorption are investigated. The spectroscopic techniques used are TRLIFS, XPS, XAS, DRIFT.

• Finally, data simulations are performed using only these defined equilibria in order to calculate the corresponding equilibrium constants.

The substrates already studied are the solids ZrP2O7, Zr2O(PO4)2, Th4(PO4)4P2O7, LaPO4, ZrSiO4, ZrO2 and a montmorillonite. We have started to investigated the solids TiO2, FeOOH, Al(OH)3 zirconium hydrogen phosphate and the single crystals TiO2, ZrO2 and SrTiO3 which will take probably several years. The actinides under study are the trivalent curium, the hexavalent uranium and the plutonium.

Equipments: Hot lab (glove boxes, alpha, beta detectors,…), TRLIFS (uranium, curium).

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University of Liège, Laboratory of coordination and radiochemistry,

Belgium

Research activities The laboratory of coordination and radiochemistry of the University of Liège is essentially involved with two areas of research, both related to the solution chemistry of f elements (actinides and lantha-nides). On the one hand, the laboratory synthesizes Gd(III)-containing contrast agents for magnetic resonance imaging. Some of the compounds produced in the laboratory are currently used in hospitals. On the other hand, it prepares extracting agents for the reprocessing of nuclear wastes and it investi-gates the properties of f elements in solution. Various nuclear magnetic resonance (NMR) methods are used on a regular basis to progress in these two areas of research.

In addition to having access to a range of one- and two-dimensional heteronuclear NMR spectroscopic techniques, the laboratory is equipped with a rather unusual instrument called a NMRD spectrometer that allows one to measure the dispersion of the longitudinal relaxation time T1 over a large frequency domain (0.01 to 80 MHz or 3x10-4 to 2 T). Actinide specialists for essentially two reasons do not often use NMR: one is rarely welcomed in the NMR room with a highly radioactive sample and NMR is considered as a poorly sensitive spectroscopic technique. Remarkable progresses have been achieved recently in attempts to improve its sensitivity but NMR is still deemed not sensitive enough to be use-ful in radiochemistry. To alleviate the sensitivity problem, we recently acquired a NMRD spectrome-ter with which we measure the relaxation time of the solvent instead of obtaining information directly on the solute. The solvent protons are most abundant (water is 111.1 M in protons) and the sensitivity problem is no longer a major difficulty. Of course, one is now looking at the effects of the solute on the solvent magnetic properties rather than directly on the solute.

Dia- and paramagnetic substances have a direct effect on the relaxation time of a solvent through dipo-lar interactions and electronic delocalization processes. The NMRD technique is well suited for the study of:

• The solvation of paramagnetic ions either as such or complexed by ligands: solvent exchanges in the first coordination sphere, outer sphere effects,

• Dynamic processes in metal complexes: rigidity of the coordination sphere, aggregation phenom-ena, rotational correlation times

• Complexation processes: stoichiometry, thermodynamic and kinetic stabilities

• Changes of oxidation states

• The magnetic properties of lanthanides and actinides

We embarked on a NMRD study of lanthanides and actinides along theses lines. For instance, the for-mation and dynamic properties of macrocyclic lanthanide complexes of interest in nuclear waste re-processing is investigated in acetonitrile. Aggregation phenomena appear to play a major role in the extraction processes. The solution structure of the extracted species is also unravelled by NMR. More-over, a comparison of the changes in relaxation times induced by Gd(III) and Cm(III) is carried out by NMRD. The partially non-S character of Cm(III) is readily seen in the relaxation dispersion NMRD curves of this ion in water. This partially non-S character results in shorter electronic relaxation times and it is possible to record NMR 1H spectra of Cm(III) complexes while this is not possible in the case of Gd(III). The solution behavior of complexes formed between humic or fulvic acids and Gd(III) can also be analyzed by NMR techniques. NMRD gives access to the rotational correlation times and to the rigidity of the metal coordination sites. The humate fractions of very high molecular weights are not those that form the most rigid entities.

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Finally, it should be noted that an entire floor of the laboratory building is devoted to radiochemistry. A fluorescence spectrometer with detection in UV-visible and in near-infrared light and the NMRD instrument are located on that floor. The laboratory is fully equipped for the handling of radionuclides (glove-boxes in inert atmosphere, α, β, γ counting, γ spectrometry, scintillation counting,) and it has a stock of macroscopic quantities of transuranium actinides (237Np: 7.5 g, 239Pu: 3.5 g, 241Am: 600 mg, 244Cm: 100 mg). The coordination chemistry lab also occupies an entire floor and is equipped with all the equipment needed for coordination chemistry and organic syntheses (glove-box in inert atmos-phere, high performance liquid chromatographs, ion spray mass spectrometry, crystallography, pH-titration…). In addition to a director, six PhD students and three technicians are working in the labora-tory in 2002. The laboratory is opened to all scientists interested in a collaborative project.

Interest in the ACTINET scope. • The reader will not be surprised that we are specially interested in an access to the NMR spec-

trometer that will be installed in the ATALANTE laboratory (France)

• A comparison of the results obtained by NMR with data collected by other techniques will be most useful. Having access to synchrotron radiations (FZK) in a "hot" environment is particularly interesting in this respect. Having access to high sensitivity fluorescence equipment would be most useful too.

Suggestions for a scientific program. • Reliable parameter sets that can be used for modelling the solution structure of f elements com-

plexes and solvates

• It would be nice to have samples of humic acids from the main repositories of nuclear wastes so that we could all work on the "same" material (preferably after separation by ultrafiltration".

• Research on actinides in different oxidation states in solution.

Comparison between properties of lanthanides and actinides in the same experimental conditions (in solution).

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Forschungszentrum Jülich (FZJ),

Institut für Sicherheitsforschung und Reaktortechnik , Germany

Scope 1. Chemistry and physics in solution and solid phases Chemistry of separation: For analytical reasons to quicker and better separation of actinides from other radionuclides and to have better inter-actinide separation we are developing a routine flow-sheet based on solid phase extraction using and/or developing new extraction resins and on the basis of re-versed phase separation by HPLC. For P&T-programmes reasons we are developing new liquid/liquid extraction compounds for esp.: Am-Cm/Lanthanide separation. Our intension is to find an organic compound, which allows a direct extraction with high yield from HLLW. Jülich succeeded in getting the first An/La-separation compound in Europe on the basis of Dithiophosphin-acids able to perform the extraction at high acidity. To develop even better separation compounds we perform molecular modelling, slope-analysis and EXAFS for better understanding the extraction effect and the structure of the actinide-compounds.

Fixation and immobilization: To bring Pu and other actinides into a form suitable for storage, trans-mutation or disposal the actinides have to be embedded in a matrix. Tow different matrices are in de-velopment: (Y, Zr) 02 and Th02. Th02 is a double purpose matrix for actinides. It can be used for dis-posal or as fuel/target material for incineration of actinides. The investigated fabrication routes are Powder Blending and solid state sintering, co-precipitation, Sol-gel process and infiltration (soaking) technique. Points of interest are: characterization of ceramics, loading capacity, transfer of ceramic to crystalline structure; characterization under disposal conditions is also performed.

Scope 2. Chemistry of actinides in the geological environment Our objectives are focussed on direct disposal of oxidic HTR- and metallic or U3 Si2 research reactor fuel and the corrosion behaviour of these two different (graphite and SiC an Al) fuel claddings. Inter-actions of the actinides with the matrix material in different aquatic/saline-leachants are investigated.. Beside this the secondary phase formation after fuel element corrosion and the retention potential of these phases is of highest interest. Identification, characterization and optimization are topics of our future work concerning near field source term.

Scope 3. Basic properties and evolution of actinide materials under irradiation“ Basic research of pure actinides: To get better and more accurate data on the behaviour of actinides we are irradiating actinides with proton beams in the area of 1,5 – 7,5 GeV with a beam intensity of 3 * 1013 protons at DUBNA-nuclotron. At the same time we are focussing the proton beam on Pb resp. U-blankets to produce neutron. The transmutation rates of the actinide targets (Pu-239, Am 241, Np-237) at different intensities and energies is investigated by measuring the amount of different fission products. The conversion of transmutation rates into spallation neutron numbers and comparison with model calculations is performed. These calculations are based on two model codes: LAHET from Los Alamos Nat. Lab. and DCM/CEM from JINR, Dubna.

Basic research of immobilised actinides: Actinides for storage, transmutation or disposal will be im-mobilized in ceramic matrices. Two different matrices are under investigation: (Y, Zr)02 and Th02. These actinides bearing ceramics are irradiated also under the aspect of fabrication [Powder blending and solid state sintering; co-precipitation, sol-gel process, infiltration (soaking)]. Points of interest: ceramic-matrix and actinides-behaviour under irradiation; alternating effects matrix-actinides, phase formation under irradiation.

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Institut für Kernchemie, University of Mainz, Germany The Institut für Kernchemie, Univ. Mainz, is interested in joining the “Network of Excellence for Ac-tinide Sciences”. Section I describes the institute’s resources and research activities in the field of acti-nide sciences, which are focused on the Scientific Scopes 1 and 2.

The research activities given in Section I reflect the prominent scientific interest of the institute. Therefore, Section II contains only one suggestion for the scientific programs of the network.

I. Description of the resources and activities

Scope 1. Chemistry and physics of actinides in solution and solid phases (JRC-ITU) &

Scope 2. Chemistry of actinides in the geological environment (FZK-INE)

Innovative analytical chemistry

• Ultratrace analysis of actinides in environmental and biological samples by Resonance Ionization Mass Spectrometry (RIMS)

• Particle analysis by laser desorption and ionization time-of-flight spectroscopy

• Routine analysis of a large number of samples by instrumental neutron activation analysis (INAA) and by beta-delayed neutron activation analysis (DNAA) for uranium and plutonium

Aquatic chemistry of actinides

• Complexation of actinides with various ligands relevant for actinide storage conditions

• Complexation of U(VI) and Np(V) with humic substances (EXAFS combined with electrochemis-try, UV-vis, and TRLFS measurements in collaboration with FZR)

• Determination of the humate complex stability constants for the different oxidation states of Np and Pu

• Redox behavior of Np(V) and Pu(VI) in solutions containing humic substances, kinetics and re-versibility

• Sorption of Np and Pu and their humate complexes on mineral surfaces

• Speciation of U(VI) and Np(V) on calcite and calcium silicate hydrate surfaces by XPS and EXAFS

Physico-chemical and dynamical properties of actinide ions

• Electromigration measurements of ion mobilities in aqueous and non-aqueous electrolytes

Computational chemistry

• Modeling of actinide compounds with relativistic density functional theory (DFT) in collaboration with V. Pershina (GSI) and by DFT and molecular dynamics in collaboration with S. Tsushima (Univ. of Tokyo)

Development of methods

• Development of the regularization method for analysis of EXAFS spectra (collaboration with Rus-sian Academy of Sciences, Yekaterinburg and FZR)

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Scope 3. Basic properties and evolutions of actinide materials under irradiation (CEA-DEN-SOE)

The institute does not have any research activities in this field.

Cornerstones of the ACTINET project

Pooled facilities (FZK-INE)

The Institut für Kernchemie, Univ. Mainz, can offer the members of the Network access to the follow-ing equipment and facilities:

Laboratories for handling of actinides RIMS: Nd:YAG-Ti:Sa-laser-TOF, cw diode laser-QMS MALDI-TOF and laser systems X-ray photoelectron spectrometer UV-vis spectrometer Capillary electrophoresis-ICP-MS Electromigration apparatus Perturbed angular correlations Low-level α-particle spectroscopy 3He counter TRIGA research reactor

Training and education possibilities (JRC-ITU)

A major activity of the Institut für Kernchemie, Univ. Mainz, is the training and education of students and young researchers in actinide sciences. The following courses can be made available within the network:

Basic laboratory course in nuclear chemistry (two weeks) Advanced laboratory course in actinide chemistry (four weeks) Lectures on actinide chemistry and physics Training in EXAFS data analysis (one week)

Dissemination of knowledge on actinide sciences (CEA-DEN-SOE)

The institute is interested in an improvement of the dissemination in actinide science and education. It suggests that workshops are organized within ACTINET/CAPITAN that are devoted to selected topics of the Scientific Scopes and Cornerstones.

II. Description of scientific programs of actinide science of prominent scientific interest

In addition to the topics listed in the Project Summary, the analytical chemistry of actinides should be added to Scope 1.

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Technische Universität München, Institut für Radiochemie (TUM-RCM),

Germany 1. Research activities The Radiochemistry Institute in Munich (RCM) is located in close proximity of the Munich research reactor FRM-II and encompasses about 2500 m2 of lab and office space. Being an institute of the tech-nical university of Munich (TUM) the RCM is quite unique in Bavaria but also in Germany. The RCM possesses some of the infrastructure which normally is found only at large national research centers. These include three hot cells licensed to handle <1015 Bq of 60Co (or equivalent) and which are also licensed to handle actinides, several glove boxes, and different classes of laboratories for low, medium and high levels of radioactivity as well as extensive licenses to handle radioactive materials including fissile materials. Quite unique is also the access to large scale facilities, such as the new intensive neu-tron source FRM-II (expected to start operation in spring of 2003) as well as the Munich Tandem ac-celerator which is being used for accelerator mass spectroscopy (AMS).

With the appointment of Prof. Dr. Andreas Türler (chair of radiochemistry, since 18.12.2001) parts of the institute were rearranged and new research topics were introduced. Currently the following re-search topics are investigated:

Production of new radionuclides for radiopharmaceutical applications:

At RCM a new professorship for radiopharmaceutical chemistry is being established. In close collabo-ration with nuclear medicine it will be possible to synthesize hitherto commercially not available ra-dionuclides such as 225Ac, link them to biologically active pharmaceuticals and apply them as diagnos-tic or therapeutic tools in nuclear medicine. Currently, the production of Ci amounts of 225Ac by proton irradiation of 226Ra and the development of a 90Y generator system are being investigated. At TUM a 22 MeV proton cyclotron is available. Also production of reactor based nuclides such as 76As or 177Lu are investigated.

Radioanalytical chemistry:

At the new research reactor FRM-II several irradiation facilities for neutron activation analysis (NAA) will be available. These range from high flux irradiation positions (4⋅1014 cm-2⋅s-1) to a fast rabbit sys-tem (transport time 200 ms) to a large volume irradiation facility. Furthermore, RCM is constructing a facility for prompt gamma-ray neutron activation analysis (PGNAA) at a cold neutron guide. RCM also has a number of conventional analytical tools at its disposal that were modified to analyze radio-active samples such as ICP-OES and SEM-EDX. The installation of a high-resolution ICP-MS is planned. Ultra low levels of radionuclides (> 104 atoms) are being determined with the aid of AMS at the Munich tandem accelerator, i.e. the determination of Pu in depleted uranium)

Basic radiochemical research:

RCM is involved with the chemical characterization of single atoms of superheavy elements. Re-cently, the first chemical investigation of 7 atoms of the element 108, Hassium was accomplished. Currently, methods to isolate and characterize elements 112 and 114 are being developed. Two pro-jects are concerned with nuclear safety and the disposal of radioactive waste. In one project the stabil-ity, speciation and migration of actinides attached to aluminosilicate colloids is investigated. In a sec-ond project processes to selectively extract tritium form aqueous waste are studied.

Applied and technical radiochemistry:

One group of RCM studies a wide variety of radiochemical problems in the form of R&D projects that are initiated by nuclear industry and also the authorities. RCM is operating a large gamma tomography

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set-up to characterize the contents of radioactive waste bins. Also a tomography system with fast neu-trons has been constructed. Other R&D projects are concerned with the analysis of irradiated Be/Cd moderator elements form FRM-I or the analysis of depleted uranium samples from the Kosovo war.

2. Resources Large scale research facilities

• Research reactor FRM-II with installations for NAA (INAA, RNAA), short time irradiation facility, rapid rabbit system, PGNAA with cold neutrons.

• 15 MeV Tandem accelerator with AMS and microbeam (SNAKE) • 60Co gamma irradiation facility (ca. 1E15 Bq) • 22 MeV proton cyclotron

Instruments

• Alpha-, beta- und gamma spectrometry (i.e. about 25 Ge detectors). • GC-MS (quadruple, with ECD and PID). • SEM/EDX. • Fourier-Transform-Infrared-Spectrometer FT-IR. • 2 ICP-OES. • ICP-HRMS (planend). • HPLC. • GF-AAS

Infrastructure

• about 1500 m2 of lab space • 3 hot cells (<1E15 Bq 60Co also licensed for actinides) • Radiochemical laboratories types A, B, C licensed for handling fissile materials (15 g Pu, 150 g

235U) and other radioactive materials • Several alpha glove-boxes, inert gas boxes

3. Proposed scientific projects The RCM is interested in two scientific projects:

Influence of colloids on the migration of actinides

In order to assess the long term safety of a nuclear waste repository, the geochemical behavior of long-lived actinides needs to be investigated. Geochemical reactions that mobilize or immobilize actinides in the aquifer are numerous and not independent from each other. Of the known geochemical reac-tions, hydrolysis, sorption, co-precipitation and mineralization lead to an immobilization, whereas complex formation with ligands contained in the groundwater as well as colloid formation can lead to a mobilization of actinides. Among the mobilization processes, formation of actinide containing col-loids is poorly understood, although its importance is obvious, given several experimental observa-tions of colloid-borne migration of actinides.

Natural aquifer systems are prone to produce metal ion silicate colloids that have a large binding ca-pacity for actinides. We therefore suggest to continue our investigations on the formation of aquatic colloids, the incorporation of actinides into them and to predict their migration behavior. Due to the very complex formation pathways of colloids in natural systems, we propose to simulate and investi-

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gate single reactions in artificial systems in the laboratory and thus gain a deeper understanding of the naturally occurring reactions.

The network structure of ACTINET and CAPITAN would allow us to intensify our collaboration with the Institut für Nukleare Entsorgung (INE) of FZK and to take advantage of the extensive instrumenta-tion available at INE that goes beyond the capabilities of RCM, such as LIBD (Laser Induced Break-down Detection) or TRLFS (Time-Resolved-Laser-Fluorescence Spectroscopy).

Investigation of high density fuels under irradiation

Within 10 years of operation with highly enriched uranium silicide fuel (93%) the compact fuel ele-ment of the research reactor FRM-II has to be converted to a fuel of lower enrichment. Currently there is no fuel of lower enrichment available which would not severely compromise the performance of the current design. A feasible approach might be the development of high density fuels, i.e. monolithic U-Mo fuel. RCM would be interested to contribute to the development and test of new fuels for research reactors in order to ensure the efficient future operation of the FRM-II reactor. Clearly RCM is lacking some of the necessary means to initiate such a study. But with the expertise and the resources of the ACTINET and CAPITAN network important contributions to solve this problem could be made.

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University Toulouse, Laboratory for Quantum Physics (LPQ)

THEORETICAL EXPERTISE FOR THE MODELLING OF COMPLEXES

CONTAINING HEAVY ATOMS

Project for the creation of a ˝User laboratory˝ at theLPQ devoted to modelling

Introduction The organisation of research in Europe must help improve the efficiency of the participants in this research by concentrating expertise, technical and experimental facilities. In the spirit of this princi-ple, several projects and european programmes have been conceived to improve access to resources that are not found in most laboratories (heavy equipment, such as particle accelerators or access to specialized computing facilities).

We propose to extend this model to another type of resource, and to call it: Theoretical expertise for the modelling of complexes containing heavy atoms. The aim would be to create, in a laboratory belonging to the network, an enviroment that would enable each research worker to come to grips with the problems of modelling chemical systems related to the themes that are developed in the CAPITAN network. The different resources that are necessary will be described below; they include both human (expertise and possible collaboration with research workers who are specialists in the field) and physi-cal components (access to different local and national computing equipment and to appropriate soft-ware). The concentration of all these facilities should enable interested workers to make rapid pro-gress in their research.

Scientific aspects

Scientific programme

It is difficult to predict an exact list of the exact themes at this moment, since they will depend on the requests of the users. However, concerning the activities of a theoretical nature that such a centre might pursue, we would like to follow the main points of the document that we had prepared after the first meeting of CAPITAN (see annexe 2). Briefly, we wish to extend the capacities of ab initio meth-ods as applied to actinide complexes, to take solvent effects into account and possibly to consider the effects of dynamics.

Scientific animation

It is clear that if such a centre were to be created, it would become a pole of attraction for theoreticians involved in the study of relativistic effects, a field in which the LPQ has already forged solid relation-ships, thanks to its participation in the REHEC network (Relativistic Effects of Heavy Elements in Chemistry) supported by the ESF, and to its organisation of different events such as meetings and workshops at the European level.#

Operation

To ensure the efficient operation of such a centre of excellence it is clear that the workload would have to be distributed according to the possibilities offered by the laboratory concerned. It would seem necessary to envisage a system of applications, and to respond to these according to the potential ex-pertise available. Once an application is accepted, the group would commit itself to ensure that all the necessary resources are available to candidates. At a later date, it might be possible to host external theoreticians, either European or not, who could propose and develop their own collaborative themes

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with experimentalists. This mode of operation would enrich the scientific life of the European net-work considerably.

Practical consideration

Personnel

The first personnel available in the Centre will be the resident scientists (annex I) and the visiting sci-entists. In particular, we propose that such a centre welcome for short stays (15 days to three months) other theoreticians willing to develop their own collaboration with experimentalists in the specific field of actinide complexes.

In one-way or another (recruitment, contracts, etc), it would be necessary to strengthen the labora-tory’s forces in computer scientists and/or numerical analysts. One of the vocations of such a centre would be to ensure not only that various standard computer programmes are maintained and made available to users, but also that new developments be planned and incorporated into working codes.

Physical resources

One must distinguish between the resources appropriate for studies that are demanding, or very de-manding, needing access to national or European centres, and the essential local equipment that will enable trial calculations to be undertaken, difficulties to be identified and that will enable access to the major centres to be limited to really large-scale studies.

Location

Such a centre could be located at Toulouse, in the Laboratory of Quantum Physics, at the Paul Sabatier University (UMR 5626 associated with the CNRS), where there is already a relatively large team of research workers who devote part or all of their activity to molecules containing heavy atoms.

Practical considerations

If such a centre were to be created, given the structure of the University at Toulouse, several practical problems would need to be solved, essentially concerning boarding of visiting people but these request several other laboratories that are concerned by similar problems.

Scientific project: Focal points for a program for computational chemistry within AC-TINET on the physics and chemistry of the actinide elements.

Background

The possibility to use computational/ theoretical chemistry to attain chemical information at the mo-lecular level, the geometry of chemical species, the mechanism of their transformations and the nature of the chemical bonding, has increased dramatically over the last decades. Up to the mid 90:ies, appli-cations of quantum chemical methods to molecular systems containing actinides and/or lanthanides were restricted to very small systems, mainly atoms and diatomic molecules and therefore the interac-tion with experimental chemistry was limited. The theoretical problems were related to the magnitude of relativistic effects, the large number of electrons that had to be treated explicitly even for small sys-tems, the semi-valence character of the outer core shells, relatively diffuse 5f-shell which participates actively in the bonding and a dense (band) density of states in the case of open f-shell configurations. However, during the last 5-10 years cooperative actions issued from many theoretical groups (particu-larly in Europe, coordinated by the Relativistic Effects of Heavy Elements in Chemistry (REHEC) network sponsored by the European Science Foundation) have largely changed this situation. Effective stable scalar relativistic methods were put to practical use around 1990, the development of spin-orbit

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theory during the 90's made accurate calculations if not routine so at least perfectly possible even for fairly complicated systems, efficient and reliable Effective Core Potentials have been developed and tested and Density Functional Theories have become applicable. The latter development is important since standard CI techniques are hampered by the need to correlate too many electrons.

The last five years have seen an increasing number of applications to systems of direct importance for experiment. Several studies on problems of direct experimental significance such as structures, and the mechanism of exchange reactions in the liquid phase, electronic, infrared and Raman spectra, intra-molecular reorganizations and redox reactions have appeared. Most of these studies have been com-bined experimental-theoretical studies where theory has been used as a direct complement to experi-mental observations.

In spite of this rapid development the field is in its infancy, and a number of improvements in existing computational tools as well as new developments are needed. For example, spin-orbit methods based on the LS coupling scheme and quasi-perturbation techniques are reliable but become cumbersome to use when the number of chemically important states increases, as is the case for open f-shell systems, and alternatives should be developed. The DFT method has been used with success in many cases, but fails for the important redox reactions and seems less reliable than for lighter elements for reaction energies. The difficulties to carry out standard correlation calculations makes it most important to de-velop an efficient, stable and reliable DFT functional applicable to many areas in actinide chemistry, in particular to systems containing many large ligands, as encountered in many technologically impor-tant processes at the back-end of the nuclear fuel cycle, but also in ground and surface water systems, in the latter case as a result of release from nuclear installations.

The development of Effective Group Potentials (which can allow to reproduce the effects of very bulky ligands without the specific inclusion of atoms (nuclei and electrons) in the calculation) will facilitate both "conventional" spin-free calculations and a more accurate treatment of spin-orbit effects in systems containing a large number of atoms.

Quantum chemical methods typically provide information about reactions in the gas-phase and it is therefore necessary to develop models that take solvent effects into account. Such models exist to-day, but they must be developed to a higher level of accuracy, in particular for systems containing ionic species. Large systems, such as actinide species contained in solution can also be treated using mo-lecular mechanics/ molecular dynamics. These methods allow new problems, such as the use of liquid-liquid extraction for the separation of different species to be described at the molecular level; they can also be used to describe large-scale weak interactions such as those between successive hydration lay-ers in aqueous solutions, molten salt systems, temperature dependent reaction dynamics etc. A prereq-uisite for reliable molecular dynamic models are precise and efficient empirical potentials, which must in part be based on high quality ab initio calculations.

Proposed research activities

It is important to state that both the problem definition in the applications, and the method- and model development should emanate from experimental questions and problems. It should be focused on :

1. New methodological developments; this includes both ab initio methods to describe strong chemical interactions within “molecular” systems of moderate size and molecular mechanics/ molecular dynamics to describe weak interactions, such as hydrogen bonding and van der Vaals interactions in large systems,

2. Applications using present day methods to chemically relevant problems.

The network should give priority to theoretical projects carried out as collaborations between theoreti-cal and experimental groups.

• The method/model development of direct relevance to applications covers the following ar-eas:

• Spin-orbit methods adapted to the actinides,

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• DFT methods adapted to the actinides,

• Effective Group Potentials to allow a simplified description of large ligands,

• An improved description of solvent effects within the continuum mode approach,

• The development and adjustment for actinides of classical molecular dynamical or Monte Carlo methods.

Examples of applications that should be started early are:

• The study of redox processes of the different actinides in model systems of relevance for appli-cations. The understanding of the rate and mechanism of these processes is very poor, despite the fundamental role that these processes play in technology. The thermo-chemistry of the acti-nides, such as free energies/enthalpies for gas phase reactions and reactions in solvents. Gas-phase reactions are important as reasonably simple model systems and a starting point for stud-ies of solvation effects.

• Donor-acceptor interactions between actinides with donors such as O, N, S; these are the “bond-ing elements” in the ligands used in reprocessing and in those encountered in ground and sur-face water systems.

A comprehensive program of research must be developed together with the scientists involved in the network. We envisage that this process can be started within the next two months.

Training

Training is another very important goal in the network; in the specific domain of quantum theory ap-plied to actinides compounds, there is very little dedicated teaching in Europe. This is mainly a result of few students and that many experimental actinide chemists are unaware of the recent advances in the field. One of the goals of the network will be to provide teaching, at the graduate or postgraduate level in two areas:

1. For quantum chemists, to provide the basic knowledge of relativistic quantum theory, the the-ory of open shell systems, correlation problems for actinides and specific aspects of DFT.

2. For experimentalists, to provide knowledge of the present possibilities of the theoretical meth-ods and “hands-on” practice in the use of quantum chemical standard programs, in order to improve the quality of exchanges and collaboration between theoretical and experimental chemists.

In order to achieve the objectives it might be practical to organize a “centre of excellence “ within the ACTINET, which can provide expertise, programs, teaching and computational means in this field.

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ACTINET Laboratory 18, 19, 20

Universities in Stockholm (SU) and Uppsala (UU) and the Royal Institute of Technology (KTH)

A common contribution A. Ongoing and planned research program in “aqueous” actinide chemistry (SU and KTH)

Chemical dynamics

Rates and mechanisms of redox reactions in homogeneous solution using experimental and theory based methods. We have completed the theory part on electron transfer between U(V) and U(VI) and are planning the experimental study. It will be possible to study the electron transfer between the car-bonate complexes, but much more difficult for the aquo ions because of the narrow range of existence of UO2(H2O)5

+. It would be very good to extend this study to the Np(V)/Np(VI) system where the Np(V) aquo ion is much more stable.

We have ongoing theoretical work on the rate and mechanism of exchange between “yl”-oxygen in U(VI) and U(V) with water oxygen. Here we are also planning some O-17 NMR experiments.

Redox reactions in homogeneous solution and on surfaces

We have made extensive theoretical studies of the thermodynamics of the U(VI) – Fe(II) redox reac-tion that has been published. The size of the computations makes it necessary to develop new models in order to allow a more detailed chemical description of the systems. Such a model is now available and a manuscript is in preparation. This model will be extended to surfaces in order to allow modelling of redox reactions of sorbed species.

The chemistry of excited states.

We are planning theoretical studies of the chemistry of the long-lived fluorescent state of U(VI) in order to determine coordination geometries, ligand exchange dynamics etc., in order to allow compari-son with the ground-state chemistry.

Coordination chemistry of tri-valent actinides and lanthanides.

This program is under way with an assistant professor in charge. The first stage will be a comparison of donor characteristics of the group O(-II) and S(-II) and N(-III) and P(-III) for lanthanides and acti-nides. We will in particular study “electronic” effects that might be used in the rational design of new ligands for separation purpose. The second part of this study will involve comparison of coordination geometry of lanthanide and actinide complexes, also in order to optimize ligand design for separation purposes. In these studies we will also keep an eye open for applications of the complexes as catalysts.

Coordination chemistry of tetravalent actinides.

Theoretical studies that we started several years ago and also existing crystal structure data indicate highly variable coordination geometries for the tetravalent actinides. Information of this kind is impor-tant both for the chemical modeling of actinides in solution and for the design of ligands for separation purposes.

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Theoretical development.

We can see a need for use of molecular mechanics and molecular dynamics methods in several of the projects outlined above. A first step will be to compare our previous ab initio results with QMM meth-ods (quantum mechanical molecular mechanics). It is essential to have reasonably large repertoire of theoretical methods in order to address the chemical problems outlined above in order to avoid method dependent bias.

B. Research activities at University of Uppsala The actinide activities of the Condensed Matter Theory Group involve theoretical modelling of actinide based materials in general, including metals, inter-metallic systems, magnetic ma-terials, surfaces, superconductors, oxides, compounds and semiconductors. The models used are based on density functional theory, total energy calculations, electronic structure, phonon spectra, molecular dynamics simulations, Monte Carlo simulations and analytical work with model Hamiltonians. Methods used for the electronic structure/phonon spectra total energy studies are; linear muffin-tin orbital methods (ASA, full charge density and full potential), linear and non-linear augmented plane wave methods (including non-collinear theory), alloy theory using the coherent potential approximation and plane wave pseudo-potentials. Issues that are addressed are connected to hardness and elasticity of materials, structural phase tran-sitions, magnetic phase transitions, high pressure, alloy formation, catalysis, interlayer ex-change interactions, surface and interface magnetism.

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Chalmers University of technology, Department of

Nuclear Chemistry

Scientific research areas Scope 1: Chemistry and physics of actinides in solutions and solid phases

Ongoing projects

• Solubility of Pu under reducing conditions

Production of Pu in different oxidation states Speciation of Pu in granitic groundwaters or 0.1 M NaClO4 (would like to use techniques within the network) ICP-MS measurement of water concentrations (possible to measure lower concentrations within the network) X-ray diffraction of solid phase (Not easy today, would like to use the network)

• Solubility of Np under reducing conditions and high pH

Involves same as for Pu

• Coordination and complexation studies for different extracting agents used for selective separa-tion in the transmutation process of spent nuclear fuel. In solvent extraction studies of phosphate complexation of actinides. (Using different solvent speciation techniques available within the net-work)

Scope 2: Chemistry of actinides in geologic environment

Ongoing Project

• An-sorption (Pu, Np, Am….) onto well-defined solid oxide phases

Speciation of An in granitic groundwaters or 0.1 M NaClO4 (would like to use techniques within the network)

ICP-MS measurement of water concentrations (possible to measure lower concentrations within the network)

Exafs on solid phases to decide what species are sorbing (only within the network

• Solubility of spent UO2-fuel under reducing conditions

RIX to decide what oxidisation state that is sorbing (Np, Pu, U) (within the network)

Facilities • Alfa-box laboratory (5 g Pu maximum per box)

• Alfa-box with special facilities (Ultracentrifuge 280 000 g, UV-VIS spectrofotometer, Owen 2000°C)

• Hot-cell (max 400 GBq Co-60), Spent fuel leaching ongoing in high-pressure vessels

• High-pressure vessels (50 bar max.) with possibility to take liquid samples and use different at-mosphere

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• Radiochemical laboratories

• Detectors for alpha, beta gamma measurement

• ICP-MS for radioactive samples (1ppt U-235 report limit)

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Københavns Universitet (KU), NanoGeoScience Group of Geologisk Institut

What we are doing: Fundamental study of mechanisms at the solid/fluid interface; uptake and release of trace components in general; focus on environmentally relevant topics.

Summary of Current Projects:

• Eu uptake on calcite; solid solution formation; solid-state diffusion; natural lanthanide abundance in calcite.

• Fluoride adsorption/precipitation on calcite; groundwater remediation by reactive barrier.

• Biomineralisation; coccolith (calcite plates on algae) crystal orientation; structure; effect of organic molecules (polysachharides, organic acids) on crystallisation.

aces.

• Recrystallisation and uptake; 18O fractionation and equilibration; solid-state diffusion.

• Fe(III)-oxides; morphology; uptake of trace components; morphology changes; adsorption and its inhibition of dissolution.

• Adsorption and behaviour of pesticides; control of adsorption through functional group structure and its response to atomic structure of substrate.

• Fe(II)-oxides; synthesis methods; characterisation; adsorption; redox processes.

• Fe-oxidising bacteria; role in trace-metal uptake; role in organic component uptake.

• Bacteria interaction with mineral surfaces; breakdown of organic contaminants.

• Local scale magnetic properties of magnetic minerals.

• Fly Ash characterisation; treatment methods; reactive barrier development; heavy metal transport and immobilisation.

• Fe-isotope fractionation; tool for determining genesis and history of Fe-oxides in fractures.

• Sulfate reduction; FeS2 formation on Fe(0) reactive barrier for groundwater remediation; electrochemical processes on Fe(0) surf

Group Composition:

Currently about 15 members

• Masters students (program takes 2 to 2.5 years after bachelor) - 8 in various stages

• PhD or equivalent - 4 directly linked; 2 co-advised from outside KU

• Post-doc or equivalent - 1 (Dr. Leonid Lakstanov)

• Technical support - part-time laboratory, electronics and secretarial staff

• Academic staff - Group Leader (me) and some help from X-ray diffraction expert

• (Dr. Tonci Balic-Zunic, Assoc. Prof., Geological Institute) and ICP-MS expert

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• (Dr. Joel Baker, Senior Researcher, Danish Lithosphere Center)

• Occasional visiting scientists

Group Expertise:

Interface processes; surface-sensitive spectroscopy; molecular/nanoscale investigation; speciation; mineralogy; hydrogeology.

Facilities

laboratory facilities including: scanning probe microscope lab; computer modelling and data processing lab; 2 wet chemistry labs; solution analytical facilities; partial use of XRD and ICP-MS labs; occasional use of other in-house solids-characterisation facilities.

Preparing ACTINET 6

Description of Facilities

Own Lab: Scanning probe microscope (Atomic Force and others); AFM in glove box; wet chemistry; speciation modelling.

Access through other Labs: Surface techniques: XPS; TOF-SIMS; Solid characterisation: XRD; ICP-MS; Microprobe.

Scope where we can contribute

Scope 1

Solutions

- Interface reactions; secondary phases; colloids - Solution; interface; electrochemistry

Solids

- Micro/meso/macro approach - poly/single crystals

Method and Tools Development (more information at end)

Scope 2: Geological Disposal

- Interaction with mineral surfaces; mechansims; complexation models - Formation of secondary phases; solid solutions; kinetics; thermodynamics - Colloid facilitated transport - Bacteria and their influence - Organic components and their influence

Method and Tools Development (more information at end)

Teaching

Probably most relevant for ACTINET partners

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- Surface Analysis for Natural Materials - 7.5 ECTS points; PhD or Masters level - Hydrogeochemistry (Solution/Speciation Chemistry) - 20 ECTS; PhD or Masters

Others (available by arrangement)

- Mineralogy; X-ray Diffraction; Microprobe; X-ray Fluorescence

Dissemination

Theme group workshops functioned very well in ACTAF. We could continue that model. I could lead one sub-project with occasional theme workshops.

A theme could be chosen from:

i) process oriented, such as trace element immobilisation or surface poisoning ii) system oriented, such as Eu(II)/(III) uptake by calcite or U by Fe-oxides iii) modelling oriented, such as incorporating mechanistic information into transport codes.

Current Outlook (expected to evolve with time) What we could use (from ACTINET):

• support for travel and subsistence for student(s) (and me once in a while?) to INE or ITU for use of XPS or TRLFS?

• partial costs for running a 1 week course on surface analysis for natural materials (also possibility of full or partial funding from NORFA - Nordic countries).

• support for theme workshops such as we had for our calcite subgroup of the ACTAF My favourite topic these days is: Surface-promoted redox reactions.

Method and Tools Development - more information for Scope 2 (The Dream Part): We can learn a lot about surface processes by working with single crystal substrates because we can tailor their structure and examine interactions locally. Such thorough control allows data collection that provides direct mechanistic information and provides a good base for ab initio and molecular dynamics modelling. We have been using this approach already, in my group and in the interface geochemistry community, to a limited extent, by using cleaved mineral samples. Unfortunately, few minerals have perfect cleavage, and most solids of interest to our colleagues in the ACTINET network are too small to cleave, seriously limiting the range of substrates we can study. One can make surfaces by fracturing, cutting and polishing, or by synthesis, but such surfaces are never flat and are rarely clean enough to provide reproducible data. A good example is FZK's recent study of adsorption onto cut surfaces of sapphire presented at the last ACTAF meeting. Irreproducibility could result from surface roughness or contamination from cutting and polishing or by surface composition inhomogeneities inherited from the original crystal. The possibility to prepare flat, uncontaminated single crystals with controlled composition would give a big push to the work foreseen for scope 2.

After years of working with surface sensitive techniques, mineralogy and solution chemistry, I know how this can be done. We need a vacuum system and some equipment that will run up to about a mil-lion Euros. I have already been making plans and contacts in Denmark and eventually, as the next natural step in the growth of the NanoGeoScience group, we will get some support from the Danish Research Council. If I can win some private funding in the meantime, it would encourage the Research Council, but if I could find about 100 K Euros from outside Denmark, things would move much faster because the external funding would add a "stamp of approval" to the case. Once the equipment is in place, we could certainly use it to produce non-radioactive single crystals for use by the ACTINET partners as well as for projects in Denmark. If there was sufficient need, for example simply because

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of volume or because of the desire to prepare radioactive substrates, we could make a copy of the equipment for installation at INE, ITU or CEA.

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UNIVERSITY OF HELSINKI, LABORATORY OF

RADIOCHEMISTRY, Finland

Research Areas Laboratory of Radiochemistry, University of Helsinki, is willing to participate in the ACTINET and CAPITAN networks and carry out research work on three fields:

Use of uranium series as natural analogues

Naturally occurring actinides U, Th and Pa and their isotopes have been studied in the Laboratory of Radiochemistry for two reasons. First, their spatial and temporal behaviour is of interest because they can be used as in situ chemical homologues to nuclear waste actinides accidentally released to biosphere or geosphere. Secondly, naturally occurring actinides can be used as useful indicators in studying various long-term environmental processes (dating and redox-fronts). These kind of studies has been performed during the natural analogue studies at Palmottu, Finland, first from 1987 as a national collaboration and then later from 1996 as EU-funded large international project. More recently the use of U in association with Fe and Mn has been investigated to better account redox-fronts along the groundwater flow routes. During the Palmottu project various experimental approaches were developed. Information of actinide behaviour was derived by examining their geochemical partition in solid (soils, sediments, rocks, minerals) and liquid (surface and ground waters) samples. The main experimental approaches were phase selective extractions and U-series disequilibrium measurements. In phase selective extractions the aim is to obtain detailed information of actinide distribution in a sample material. This includes, in addition to selective dissolution of desired phases, investigations of U oxidation states, U(IV)/U(VI) ratio in particular.

INET.

Studies on naturally occurring U and its daughter products have utilized conventional experimental techniques like phase selective extractions and α-spectrometry. As a result of extraction mineral surface properties may be changed. This possibility has been studied indirectly using extracted rock samples as sorbents. In order to get real insight into the surface properties of extracted rock or mineral material we need facilities, which are beyond our reach. Furthermore, with performing phase selective extractions we need information of aqueous U species. This kind of speciation can be done with sophisticated laser techniques, which we don’t have either. Our Laboratory sees a great potential in developing collaboration between conventional and more sophisticated techniques. In U-series disequilibrium studies fundamental understanding of U aqueous chemistry is of great importance in interpreting observations of U distribution in any environmental samples. More close collaboration with experts in field and fundamental chemistry could be a useful task of ACT

Study on solubility and sorption mechanisms of waste actinides in the geosphere

The Finnish program for disposal of spent nuclear fuel and reactor wastes to Olkiluoto area consists also studies on geochemical behaviour of actinide elements. The Laboratory of Radiochemistry has conducted studies on sorption of U, Th, Pa, Np, Pu and Am on rock material. The tracers U-233, U-232, Th-229, Th-234, Pa-233, Np-235, Np-237, Pu-236 and Am-241 were used in low-enough con-centrations to avoid solubility limitations. The natural uranium and thorium were also studied. Ex-periments on the redox-sensitive elements were made under ambient atmospheric conditions and under controlled anaerobic laboratory conditions. Reducing (for Pu, Np and U, Tc as an additional redox-monitor) conditions were attained especially using sulfide containing deep groundwater from Olkilu-oto area collected directly to sample vessels. Mineral specific sorption has been studied using rock thin-section samples connected with optical microscopy and autoradiography. The studies included

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testing of methods for indirect ways of determination of oxidation states of the activity in solution and of the sorbed activity. Liquid extraction, co-precipitation and anion exchange were used for separation of U(IV)/U(VI), Np(IV)/Np(V) and Pu(III+IV)/Pu(V+VI).

In 2003 a new project will start to study in detail the physical and chemical mechanisms affecting in migration and retardation of nuclear waste elements in near field and farfield conditions. A major effort is directed to studies on sorption mechanisms of dissolved waste nuclides. The project will include both experimental and modelling work on the topic. The studies on solubility of four-valent actinides was started in 2001. The first actinide studied was Th. Sorption mechanisms of Th including speciation of Th in solution and of the sorbed Th is in our interest. We have experience to work under reducing conditions and sorption mechanism studies on Np and Pu are also in our interest but especially high enough concentrations of Pu are not possible to work with in the B-class laboratory we have. We are very much interested in having the possibility to co-operate under Actinet program in these topics.

lso the speciation of actinides in soil samples have been studied

ntinued, and a pecial attention is paid on 1Am, since its activity is increasing due to decay of 241Pu.

her

aps. All the laboratories are modern since the laboratory moved to a new chemistry uilding only seven years ago.

Behaviour of fallout actinides in the environment

Laboratory of Radiochemistry has studied the environmental behavior of the radionuclides from nuclear weapons test fallout since the beginning of the 1960’s. Since 1973 also Pu and Am have been included in the food chain studies, such as lichen-raindeer-man food chain. After the Chernobyl accident in 1986 laboratory has studied Pu, Am and Cm in the environment, especially their behavior in the Lake Päijänne which is the water source for Helsinki. During the last thirty years the capability to determine the activities and isotope ratios of these three elements in ultra low levels has been developed. Determination procedures are based on both classical and novel separation procedures and on alpha spectrometry. Samples have included soil, vegetation, water, sediments as well as animal and human samples. Later in the 1990’s aby sequential extraction procedures.

Studies on the behavior of actinides in the environment and in the food chains will be co24s

Resources for actinide research in the laboratory of radiochemistry To carry out certain parts of this research work Laboratory of Radiochemistry is willing to use the facilities of the offered by the network partners. It also offers its own facilities to the use of otpartners. The resources for actinide research in the Laboratory of Radiochemistry are described below.

During the last thirty years Laboratory of Radiochemistry has developed analytical procedures for the determination of actinides (Th, Pa, U, Np, Pu, Am and Cm) from a wide variety of sample matrices (soil, water, vegetation, animal and human tissues, rocks etc). Determinations are mainly based on radiochemical separations and alpha spectrometry. There are altogether twenty six alpha counting chambers in the laboratory. Liquid scintillation counting is also being used for alpha counting. Two of the four liquid scintillation counters, are low-level counters and also have the capability for alpha-beta discrimination. In addition, there are also three gamma spectrometers. The main specialty in the knowledge of actinides is their determinations in very low levels. Therefore most of the research is being done in C-type laboratories, where actinide activities below 0.5 MBq can be handled. Laboratory has also one B-type laboratory for the activities between 0.5 and 500 MBq. There are also two controlled atmosphere boxes, one in a C-type laboratory and the other in the B-type laboratory, where redox-sensitive actinide elements can be handled in oxygen-free atmosphere. For the decomposition and leaching of samples by acids for radiochemical separations there are two specialty hoods with acid trb

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Education of actinide chemistry in the laboratory of radiochemistry Laboratory of Radiochemistry is also willing to cooperate in the field education and training, especially by sending its students to the partner institutes, to special courses organized within the framework of the network and to do research in partner laboratories for their doctors thesis. In addition, the Laboratory of Radiochemistry is ready to take students from partner institutes to its own

hrough the radiochemistry program takes 2-3 years. The

ncludes laboratory practicals)

nuclides (includes laboratory practicals)

acticals)

nuclides in environmental chemistry

eeper actinide research. Laboratory of Radiochemistry grants annually

e. Presently there are two graduate students in U. All these thesis have included work on actinides.

Laboratory of Radiochemistry is willing to cooperate in the field of dissemination of data and results.

radiochemistry courses.

Laboratory of Radiochemistry is the only radiochemical institute in the Finnish universities and it gives teaching in almost all aspects of radiochemistry. Teaching in radiochemistry is given only on advanced (laudatur) levels. Prior to beginning radiochemistry studies students are recommended to study general chemistry for 2-3 years. To go tradiochemistry courses given are

• principles on radioactivity and radiochemistry (i

• radiation safety (includes laboratory practicals)

• nuclear spectrometry (includes laboratory practicals)

• analytical chemistry of radio

• environmental radioactivity

• chemistry of the nuclear fuel cycle

• radiopharmaceutical chemistry (includes laboratory pr

• radiation chemistry (includes laboratory practicals)

• tracer techniques in bio sciences (includes laboratory practicals)

• use of uranium series radio

• atmospheric radioactivity

Most important of these courses, considering the teaching in actinide science, are the analytical chemistry of radionuclides course and the nuclear spectrometry course, both of which include extensive laboratory exercises, where students learn to separate and measure actinide elements. In addition the courses of the chemistry of the nuclear fuel cycle and the of the use of uranium series radionuclides in environmental chemistry give valuable information of actinides. When doing their master’s theses, both its literature and practical part, both of which take three months’ work, many students become familiar with d4-5 masters degrees and 1-3 doctors degrees.

In the last ten years many graduate students have done the research work for their doctor’s thesis in EU institutes, two in Geel and three in ITU in KarlsruhIT

Dissemination

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Nuclear Research Institute Rez plc ; Czech Republic

Contribution of the NRI Rez plc to ACTINET • Creation of a “pool” system of facilities,

• Selection of research area subjects of broad interest and

• Organization of education and training system.

Scope 1 “Chemistry and physics of actinides in solution and solid phases” &

Scope 3 “Basic properties and evolution of actinide materials under irradiation

The main interest of the Nuclear Research Institute Rez plc in the participation in the Network of Excellence ACTINET and future CAPITAN projects is in the field of basic research in actinide chemistry. The research activity of NRI Rez is focused predominantly into the area of the chemistry and behaviour of actinide fluorides.

ia.

e.

tation Reactors.

rritory.

The NRI Rez has an interest in the basic experimental research in this area necessary for successful future technological realization of pyro-chemical and pyrometallurgical partitioning technologies.

Two from three main pyro-chemical and pyro-metallurgical fluoride partitioning technologies are long-lastingly experimentally studied in the radiochemical hot laboratories of NRI Rez.

There are chemical separation processes based on fluoride volatilization and on electrochemical separation from fluoride molten salt med

Only the “molten fluoride salt / liquid metal extraction” processes are not studied in NRI Rez because in the frame of international cooperation under the 5th FWP the CEA laboratories in Marcoule focused on this method. (NRI Rez – CEA Marcoule cooperation in the PYROREP project.)

In the area of non-aqueous actinide chemistry in fluoride systems, the NRI Rez and CEA Marcoule cover the whole European research. However CEA Marcoule is very active also in the chloride systems together with JRC-ITU Karlsruh

The Nuclear Research Institute Rez has serious interest to cover in the ACTINET and CAPITAN project the area of basic research of actinide chemistry and actinide behaviour in fluoride systems particularly under the fluoride volatility and partially (together with CEA Marcoule) in the fluoride molten salts chemistry. Our interest is to continue in basic research activities that are under development in NRI Rez, suitable and necessary for the future technological research of partitioning technologies for Molten Salt Transmu

The background of NRI Rez is appropriate to this task. The Fluorine chemistry department of the NRI Rez has more then 25 years experience in actinide inorganic chemistry. NRI Rez has been the only working place in Central and Eastern Europe with own production of fluorine gas and the laboratory is equipped for the high temperature fluorine chemistry (pyro-chemistry and molten fluoride salt pyro-metallurgy). For the actinide chemistry, the NRI Rez is equipped by alpha radiochemical laboratories with alpha glow-box technologies and by semi-hot and hot cells for high activities handling. The production of radionuclides and irradiation experiments are common in NRI Rez. The institute operates two (one experimental and one research) reactors on its te

EdThe research activities in the field of fluoride actinide chemistry research are long-term financed above all by Radioactive Repository Authority of the Czech Republic from so called “Nuclear Ac-count” and the financing is provided also for following periods. Owing to this financial support, the realization of education and training of PhD students and the work of visiting scientists from other

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institutions and universities are possible and still common. There are several PhD students in NRI Rez focusing their work to the pyro-chemistry of actinide fluorides. Moreover the chief scientists of the NRI Rez has been worked also as external teachers of the Technical university in Prague in the field of actinide chemistry and molten salts chemistry. The NRI Rez has suitable own accommodation facili-ties for guests, PhD students and visiting scientists.

The general interest of the NRI Rez to play an active role in ACTINET and CAPITAN projects in the area of the chemistry of actinide fluorides is based on the strategic intention of the Czech Republic and the Czech Power Company CEZ on extensive utilization of nuclear power.

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Czech Technical University, Department of Nuclear Chemistry, Prag

Description of the resources and activities in actinide sciences

Facilities available for work in DNC CTU: a) Standard radiochemical laboratories equipped for work with alpha emitting radionuclides at a

tracer level – up to 40 MBq (with basic radiometric, control and dosimetric instrumentation),

b) Nuclear spectroscopy laboratory (X-Ray, low-energy alpha, beta, gamma-spectrometry, LSC),

c) Atomic absorption spectrometry laboratory,

d) Bench scale facility for production of inorganic-organic composite absorbers and solid extractants with polyacrylonitrile binding matrix.

e efined.

imple model carried on within the NoE may include:

1)

b) PE from novel extractants potentially developed / discovered by other

c) als aimed at their characterisation he procedure for their preparation.

2) a

ials for actinides separation,

c) anced schemes for actinide separation from various media, including

3) Development of novel analytical methods:

The laboratories are suitable for pooling to a limited extent in that they can accommodate a few visiting workers for work on joint projects for up to several months – most probably rather under bilateral agreements than as full open access user labs. Standard conditions for access have yet to bd

Activities in actinide Sciences In scope 1: Separation of actinides / novel analytical methodology

Novel composite solid phase extractant (SPE) / extraction chromatographic systems have been developed. They comprise the extractant directly immobilised within an inert matrix of modified polyacrylonitrile and allow for very high extractant loadings (up to more than 30 wt.%). The materials may be prepared in granular form for application in packed beds or as SPE loaded filters (namely for application in analytics). The procedure developed allows incorporation of virtually any extractant, systems with several extractants have been already prepared. SPE based on octyl (phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) was tested against commercially available actinide extraction chromatography resins and showed to be about two orders of magnitude more efficient (relative to Eichrom TRU�resin) for both Pu and Am (in terms of KD) in both ssolutions and simulants of real saline waste. Future studies

Preparation and characterisation of new materials:

a) preparation of SPE based on known prospective extractants,

preparation of SNoE members,

study of physico-chemical properties of the novel materiand optimisation of t

Sep ration studies:

a) studies of the performance of the new mater

b) studies of the influence of interfering ions,

development of advradioactive waste.

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a) optimisation of the properties of SPE loaded filters for fast separations,

b) development of novel measurement techniques for these media (e.g. based on direct LSC of the actinides loaded filters),

c) application of these principles to development of novel techniques for actinides determination in surface waters.

:

ments;

blic).

ject.

Complexation of actinides with humic substances (this topic can also fit to scope 2)

Complexation of Eu (as homologue for trivalent actinides) and hexavalent uranium with Aldrich humic acid (HA) has been studied

1) Eu–HA complexation using dialysis, electrophoresis, gel permeation chromatography, ion exchange and ultra-filtration with the aim at

a) characterization of limitations and advantages of individual methods by comparison of results obtained with different methods,

b) characterisation of the complexation by parameters (stability constants) suitable for modelling surface complexation and migration of trivalent actinides in geologic environ

2) Kinetics of complexation and de-complexation of Eu-HA using ion and isotope exchange with the aim at obtaining kinetic data suitable for modelling migration of trivalent actinides in geologic environments;

3) Characterisation of humate complexes of Eu and U(VI) by free liquid electrophoresis (electro-phoretic mobility and charge of the complexes);

4) Development of models and computer codes for modelling the complexation and de-complexation of actinides with humic substances.

These studies have been supported consecutively by grants from the Grant Agency of the Czech Republic, by EU (in the frame of project HUPA - 5th FP) and by Radioactive Waste Repository Authority (RAWRA, the state waste management agency of Czech Repu

Sorption and migration of actinides in engineered and geological barriers

In the past 5 years, following studies were undertaken:

1) Sorption of actinides on bentonite and geological materials:

a) Sorption of U(VI) on bentonite in the presence of carbonates;

b) Sorption of Eu(III) (as homologue for trivalent actinides) on bentonite in the presence of humic acid and carbonates;

c) sorption of Eu(III) on Gorleben sand in the presence of humic acid and carbonates;

The data obtained were modelled using surface complexation models of the sorption in one- and multi-component two-phase systems containing a complex natural solid phase and an aqueous phase of variable composition.

We also modelled the sorption of Np(V) species on hematite and sorption of U(VI) species on weathered schist. The sorption data were obtained from the Sorption Project of OECD/NEA and we participated at the inter-comparison of the modelling in the frame of the Sorption Pro

2) Migration of actinides in bentonite and Gorleben sand

a) Modelling of the migration of up to five members of actinide chain 4n+3 (using the Kd values characterizing the individual members) was made using Kd values, solubility data and diffusion coefficient taken from literature;

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b) Modelling of the migration of U(VI) species and carbonate species in bentonite (the surface complexation model was incorporated into the dynamic equation) based on own experimental data;

lic).

ng universities.

ta;

c) Experimental study and modelling of migration of Eu in Gorleben sand.

These studies were supported by grants from the Grant Agency of the Czech Republic) and by Radioactive Waste Repository Authority (RAWRA, the state waste management agency of Czech Repub

At present, we study sorption and migration of uranium in waste rock from uranium mining with the aim to analyze the effect of humic substances on the release and migration of uranium from old spoil piles. This study is made in the frame of project HUPA (5th FP) and is supported by RAWRA.

Education and Training DNC CTU delivers a full course in Nuclear- and Radiochemistry in undergraduate and graduate (doctoral) level. A constituent part of it is a course on the Chemistry of Radioactive Elements (1 semester, 2 hours per week, i.e. 26 hours) that covers also an overview of actinide chemistry (approximately 50 % of the course / 14–16 hours) and a course on the Nuclear Fuels Technology I (1 semester, 2 hours per week, i.e. 26 hours) and II (the same extent). The courses are designed for Czech students, but may be also delivered in English if sufficient number of foreign students subscribes. An effort has been undertaken to initiate actions towards unification of European system of education in this field, which would facilitate recognition of credits amo

Dissemination of knowledge In the activities mentioned above, our group developed several models and packages of computer codes, which can be made available for the network:

1) the new complexation model, called Mean Molecular Weight Model (MMWM), capable of modelling of complexation of metal cations with macromolecular polyanion of humic acid;

2) the integrated program package STAMB-2002 enables (i) to compute the abundances of both aqueous and surface species of the sorbing element for which the necessary data are available, (ii) to estimate chemical equilibrium constants (including protonation constants) and other parameters describing speciation and surface complexation from observed experimental data, (iii) to estimate stability constants and kinetic coefficients of complexation, de-complexation reactions from experimental da

3) the code KINET enables to choose the best type of sorption kinetic equation (which can be then included into a migration code), describing experimental data, and to calculate values of kinetic coefficients;

4) the code MIV1D (1-D transport model) describes the migration of individual actinides in the near-field region of the final disposal of spent nuclear fuel or high level radioactive waste, and the code MIVCYL enables the diffusion transport of actinide chains in near-field region to be modelled and simulated.

Proposal for scientific programmes in ACTINET 1) Separation of actinides:

New methods of actinide separation based on solid phase extractants should be developed for use in nuclear technology and analysis of actinides (see WP1 for details).

2) Complexation of actinides with humic substances (HS): HS strongly affect speciation, migration and toxicity of actinides in the environment. Their complexation with actinides is still not sufficiently well described. Use of the network structure

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will facilitate coordinated effort in this respect due to availability of advanced methods of the complexation analysis in the network as well as due to the experience of the network members in this field.

3) Study and modelling of migration of actinides in geological environment:

New ways of analysis and modelling of migration of actinides in engineered barriers and geologic environment should be sought. The network structure would facilitate the employment of advanced analytical methods, available in the network, for analysis of the migration and its partial processes, and of experience of members of the network in modelling of actinide speciation and behaviour.

We propose that the present Kd approach, predominantly used in the migration modelling, be replaced by the approach based on surface complexation modelling. For systems with water flow rate exceeding values allowable for applicability of equilibrium dynamics approach, description taking into account sorption kinetics should be employed. The best ways for incorporation of corresponding sorption models into transport codes should be investigated. These new methods are particularly important for actinides, the migration of which is very complex due to their multi- and polyvalent nature and which represent the most important contaminants of the end of nuclear fuel cycle.

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Institute of Low Temperature and Structure Research, Polish Academy of

Sciences

Research areas corresponding to the ACTINET profile: Scope 1 “Chemistry and Physics of Actinides in Solution and solid Phases”

Subtopic: Basic properties of actinide compounds in poly- and single-crystalline form

Areas of interest:

Anomalous phenomena in 5f-electron systems:

• ·Heavy-fermion systems – magnetism and superconductivity.

• ·Dual nature of 5f electrons in actinide intermetallics

• ·Non-Fermi liquid systems. Low-carrier materials and Kondo insulators.

• ·Intermediate-valent systems. Low-dimensional materials.

• ·Interplay and coexistence of magnetic order and superconductivity.

• ·Magnet/superconductor multilayers.

• ·Theory and application of magnetic superconductors.

Nonmagnetic Kondo effect in crystalline solids:

• ·Structure of defects and appearance of nonmagnetic Kondo effect.

• ·Interactions between conduction electrons and nonmagnetic impurities.

• Electron-transport properties and thermodynamics of novel Kondo systems.

Transport properties in strongly and moderately correlated spin systems:

• ·Electron-transport properties of strongly correlated spin systems.

• ·Carrier-scattering mechanisms in novel spin systems.

Inhomogeneous charge and spin ordering in strongly correlated electron systems:

• ·Mechanisms of charge and spin superstructures formation.

• ·Evidences of various types of charge and spin ordering in novel materials.

• ·Influence of the inhomogeneous ordering on physical properties of materials.

• ·Phase transitions in materials with charge and/or spin superstructures.

Critical phenomena:

• ·Phase transitions in classical systems in confined geometry.

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• ·Low-dimensional spin and fermionic systems near the critical point.

Resources Synthesis of powders, polycrystals and single crystals (solid state reactions, mineralisation, flux technique, chemical vapour transport)

• Vacuum systems

• Argon glove boxes

• Arc-melting furnaces

• Induction furnace 30 kW

• Graphite furnace for temperatures up to 2400ºC

• Resistance furnaces (one and two zones) for temperatures up to 1100ºC

• Setup for hydrides syntheses at pressure up to 15 MPa and temperature up to 400ºC

Structural studies

• Single crystal 4-circle X-ray diffractometers with CCD detector (T: 4-700 K)

• Powder X-ray diffractometers (T: 12-1600 K)

• Transmission electron microscopes (200 kV, resolution 0.24 nm and 90 kV, res. 1 nm, T up to 1100 K)

• Scanning electron microscope with EDX spectrometer (30 kV, linear resolution 5 nm)

Magnetic studies

• SQUID magnetometer (B up to 5.5 T, T: 1.7-800 K)

• AC susceptometer (T: 4-325 K, AC field up to 1 T; DC field from 0.00001 to 1 T, freq. 10-1000 Hz)

• Vibrating sample magnetometer (T: 4-280 K, B: 40 mT - 5 T)

• Induction magnetometers (B up to 0.7 T, T: 4.2-300 K)

• Magnetic electrobalances (B up to 0.7 T, T: 2-1200 K)

Resonance techniques

• Avance DFX300 Pulse NMR Spectrometer by Bruker, (resonance field 7 T, resonance frequencies 14-300 MHz, temperature range 4.2-400 K, with MAS probe)

• EPR Spectrometer ITA PWr. for X-band (freq. 9 GHz, B up to 0.6 T, T: 4-300 K)

• Mössbauer spectrometer 2330 by POLON (T: 10-900 K)

Low temperature calorimetry

• Adiabatic calorimeters for specific heat measurements (T: 2 - 430 K)

• Setup for magnetocaloric effect (T: 20 - 300 K at B up to 16 T)

• Differential Scanning Calorimeter (T: 100 - 725 K)

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• Thermobalance Linseis L81 (T: 300 -1300 K)

Electron transport properties

• 3He-4He dilution refrigerator for resistivity and magnetoresistivity (T: 30 mK - 4.2 K, B up to 16 T)

• 3He refrigerator for resistivity and thermopower (T: 300 mK - 4.2 K)

• Teslatron for resistivity, magnetoresistivity, Hall effect (T: 2 - 300 K at B up to 16 T)

• Setups for resistivity, magnetoresistivity, Hall effect, thermopower (T: 2 - 700 K at B up to 8 T and pressure up to 1.5 GPa)

• Setups for thermal conductivity (T: 2 - 400 K)

• Setup for measurements of thermoelectric power and resistivity studies (T: 0.3-300 K)

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University of Cyprus, Department of Chemistry, Cyprus

Research areas of interest Study of heavy elements and in particular f element ions, especially solid/liquid interphase reactions in aquatic systems:

a) Studies of the interaction of f element ions with chelating agents for clinical use is performed in order to determine and characterize the formed species and assess their behaviour under physiological conditions. The basis is detailed characterization with respect to complex coordination of d and f elements with concerned organic chelating agents..

ts.

.

ding.

b) Investigations on the interaction of f element ions with natural occurring ligands (e.g. hydroxide, carbonate, humate etc.), species characterization (speciation) and determination of formation constan

c) Studies and characterization of solid/liquid interface reactions of heavy elements, including f elements, on metal oxide surfaces

c) Environmental mapping of alpha emitting radionuclides.

Main Research Laboratory Equipment • FTIR and UV-Vis Spectrophotometers

• AAS Spectrometer

• NMR spectrometer

• GC and HPLC Systems

• Titration Systems and Potentiometric Equipment

• Polarography and CV Equipment

• FTIR-DRIFTS (environmental chamber) for Surface Characterisation,

• Thermal Programmed Desorption System with Mass Spectrometer (TPD-MS)

• N2-Adsorption System for Surface Analysis

• XRD Spectrometer

• Electrodeposition Units and Radiometric Equipment

Investigation of actinide science making use of the proposed network structure: Within the EC framework VI, ACTINET 6, we propose the investigation of U(VI) on metal oxide surfaces (e.g. Al2O3, CeO2 and MgO) as a function of pH, I, T and pCO2.

The investigations will mainly be carried out as part of a PhD Thesis at the Chemistry Department of our University. The experimental work will include solid phase characterisation, solid/liquid interface characterization, determination of U(VI) adsorption-isotherm under specified conditions and modelling of the interaction based on detailed process understan

We would like to take advantage of the network structure for characterisation of adsorbed species by methods and techniques available at the laboratories of other participants, especially the core member

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FZK-INE. The PhD student will (supported by a mobility grant from the ACTINET join for a longer time period the above mentioned core members laboratory and take advantage of the existing facilities for the promotion of his PhD work. Scientific visits at other institutions, as appropriate, should also be considered.

The successful implementation of the objectives of the ACTINET will be documented by the scientific visit(s) and joint publications between partners involved.

Contribution to the network structure for external users. We can offer other members of the ACTINET to make use of our laboratory resources, especially surface characterization by quantification of released species by MS as well as surface characterization by IR-reflection, both under thermal gradients. To our knowledge, this latter experimental capability is not available at other partners.

Consolidation and Exploitation of Training and Education Possibilities: We are strongly interested in those activities because:

• We have graduate students interested in participating in summer schools with for Nuclear and Radioanalytical Chemistry

urse.

• We have included in our Graduate Programme a course about Nuclear Chemistry and Radiochemical Methods of Analysis and we have interest in inviting visiting Professors for short time period (2-4 weeks, air fair costs (economy class), weekly allowance and salary covered) in order to give lectures within this co

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Initiative of Italian Scientists “Group of Thermodynamics of Complexes

(GTC)”

An initiative has been started recently to renew actinide research in Italy with respect to radioactive waste disposal. The speaker of this research group, Prof. Diego Ferri, expressed his interest in an international collaboration within the framework of the ACTINET project. In the following an abstract of his research program is presented.

Speciation study of uranium with ligands occurring in natural waters. The Group of Thermodynamics of Complexes (GTC), for COFIN 2002, proposes to devote its research activity to a theme of primary importance, the safeguard of the environment, in the form of a contribution to the study of the mechanisms which promote the migration of radionuclides, contained in the radioactive wastes, from the repositories to the biosphere. This subject certainly is of national and international relevance. The wastes cannot be disposed of in stable geological formations before 35-40 years, due to the excessive heath produced by the decay of the short and middle lived isotopes. Now this period of time has elapsed and the final disposal can be made in repositories. In some European Country, as for instance Finland and Sweden, the construction of permanent repositories based on the multi-barrier concept, is at an advanced stage. Several barriers are interposed between the vitrified wastes and the underground waters in order to delay as long as possible, their contact. But if the underground waters, in spite of all the precautions taken, come into contact with the wastes, the risks, the safety assessment, the decision-making can only be evaluated through mathematical models ("virtual analogues"), that simulate the real systems. The mathematical models need a large collection of thermodynamic data on the real systems to be able to describe them.

in water.

ynamic equilibrium.

To this effort many laboratories in the world are contributing. Italy, however is an exception. The problem does not seem to concern us. But we do have our thousands of cubic meters of radioactive wastes! In the mean time in other countries, often in joint ventures, since more than twenty years, studies have been undertaken for the realization of a model of migration of radionuclides from permanent repositories to the biosphere, by dissolution through the prevalent ligands

The migration rate, the toxicity, the bio-activity, the chemico-physical properties of the solutions containing the radionuclides cannot be predicted from the knowledge of the total concentration of metal only, although this is an important parameter. Instead a speciation is needed i. e. the partition of the nuclides among the ligands contained in water and within its various oxidation states, in addition to the composition and to the formation constants of each species. The data necessary for the speciation in systems characterized by chemical equilibrium, are only accessible by means of the criteria of Equilibrium Analysis, a discipline, unusual for environment scientist and for biologists, practiced by few researchers in the world, which is based on the measurements of one or more chemico-physical properties of the solution without disturbing the thermod

The discipline, the themes belong to the specific know how of GTC components, both at a national as well as at an international (to some extent) level. The applying group, on the basis of its experience, after a careful analysis of the existing data, believes that the following studies on the chemistry in solution of uraium(VI,V,IV) systems are either missing in the TDB or they are unreliable, particularly U(VI)-Oxalate, U(VI)-simple Organic Acids, produced by the decomposition of fulvic and Humic acids, U(VI)-sulphate, hydrolysis of U (VI) at various temperatures, hydrolysis of U(IV), necessary to interpret other data, hydrolysis of lanthanides as analogues of the actinides.

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CONTRACT N°: FIR1-CT-2002-2011 ACTINET - cordis.europa.eu fileACTINET Final Technical Report...

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Transcript of CONTRACT N°: FIR1-CT-2002-2011 ACTINET - cordis.europa.eu fileACTINET Final Technical Report...