Primary andPrimary and secondary organic aerosols secondary organic aerosols

from a diesel car during smog chamber from a diesel car during smog chamber experimentsexperiments

Roberto Roberto ChiricoChirico

Laboratory of Atmospheric ChemistryPaul Scherrer Institut, Switzerland

roberto.chirico@psi.ch

13TH ETH Conference, 22-24 June 2009

Why are we interested in aerosol particles ?Why are we interested in aerosol particles ?

Direct radiative forcingScattering and absorption of solar and infrared radiation Indirect radiative forcingAlteration of the formation and precipitation efficiency of liquid water, ice and mixed-phase clouds

Health effectRespiratory and carcinogenic effects

Importance of aerosol size (d < 1µm) and composition (PAHs associated to particles)

VorführenderPräsentationsnotizenAfter the first 2 interesting talk Ican skipmy first slide but before that I want to add that the aerosols can haave also an health effect..Aerosol particles can have an effect on the climate changes and they can have an health effect and those effects depend on…..Concerning the climate changes up to day there are big uncentanties associated to aerosols

http://immagini.p2pforum.it/out.php/i234505_13teschio800.jpg

Diesel passenger carsDiesel passenger cars

(ACEA, 2008; EPA, 2002; Automotive Industry Data Newsletter )

Number of new diesel passenger cars in Europe

0.16

0.14

0.12

0.10

0.08

0.06

0.04

0.02

0.00

DPM

[g/k

m]

2010200520001995Year

EURO 1 (1992)

EURO 2 (1996)

EURO 3 (2000)

EURO 4 (2005)

EURO 5 (2009)

EURO 6 (2014)

EU Emission Standards for Diesel Particulate Matter

VorführenderPräsentationsnotizenAn important source of particles are diesel vehicles

Dilution effect on PM massDilution effect on PM mass

(Robinson et al., Science 2007; Lipsky and Robinson, ES&T 2006)

Fine particulate mass with initial OM/BC=2 can

decrease by 50% when dilution ratio is increased

from 20:1 to 350:1

Primary Organic Aerosols (POA) contains Semi-

Volatile Organic Compounds (SVOCs) that

partially evaporate.

Primary and Secondary organic aerosolsPrimary and Secondary organic aerosols

Primary Organic Aerosols

High temperature

Ambient temperatureLow dilution ratio (10-100)

Ambient temperatureHigh dilution ratio

(1000-10000)Secondary Organic

Aerosols

OH

O3NO3

hv

(Robinson et al., Science 2007)

POA constituents as non volatileOA mainly present in urban areas

POA main constituent of OA

POA constituents as volatile

Decrease of OA

Photochemical aging of SVOCs

Considerable amount of Urban and Regional

SOAtime < 1 sec

Set up for smog chamber experimentsSet up for smog chamber experiments

Clean air generator

Smog Chamber

Heated Diluter (150°C)

Pressurised air heater (150°C)

Ambient air Excess air

Heatedline (150°C)Heated line (150°C)

EURO 3 Diesel car

Diluter

1:84

1:8

CO2 Analyzer CO2 Analyzer

SMPS

AMS

CPCAethalometer

CO, NO, NOx, O3 Analyzer

60 L/min60 L/min

7 L/min7 L/min

DC

PAS

Drier

Dilution factors: 300-1200

Idle – 60 km/h

HRHR--ToFToF--AMS and AMS and AethalometerAethalometer

(De Carlo et al., Anal. Chem. 2006; Weingartner

et al., Aerosol Sci. 2003)

3 5

3 0

2 5

2 0

1 5

1 0

5

0

µg/m

3

543210T im e a f te r l ig h ts o n (h r s )

T e m p o r a l e v o lu t i o n O r g a n i c M a t te r ( H R - T o F - A M S ) T e m p o r a l e v o lu t i o n B la c k C a r b o n ( A e th a lo m e t e r )

Aerosols are internally mixedBC can be used as tracer for chamber wall loss

[ ])/BC(t)BC(tOM(t) MeasuredOM(t) Estimated 0×=

VorführenderPräsentationsnotizenThe ecrease of BC is due to wall losses..

6 0

5 0

4 0

3 0

2 0

1 0

0

µg/m

3

543210T im e a fte r lig h ts o n (h rs )

1 .4

1 .2

1 .0

0 .8

0 .6

0 .4

0 .2

0 .0

Characteristic aging experiment Characteristic aging experiment of diesel exhaustof diesel exhaust

Primary aerosols consist mainly of BC with a low fraction of Organic Matter (OM)Photo-oxidation of gaseous organics produces SOA

VorführenderPräsentationsnotizenMass absorption efficiency doesn‘t change with time

Starting POA concentration assumed constant

Primary and Secondary organic aerosolsPrimary and Secondary organic aerosols

60

50

40

30

20

10

0

µg/m

3

543210Tim e after lights on (hrs)

SO A

PO A

BC

SOA contribution to total organic massSOA contribution to total organic mass

After 5 hours of aging SOA is 30-80 % of the Total Organic Aerosols

100

80

60

40

20

0

% P

OA

543210Time after lights on (hrs)

Idle 60 km/h

SOA (60 km/h)

SOA (Idle)

[ ] 100)/OM(t)POA(t%POA(t) 0 ×=

VorführenderPräsentationsnotizenNow let‘s have a look at the differences between POA and the OOA….

OrganicOrganic

Aerosol Mass Aerosol Mass SpectraSpectra

Discrimination between ions with the same nominal mass

Ions grouped into 4 different organic classes depending on the atom combination

Average mass spectrum for an ensemble of submicron particles with a time resolution of few seconds

High resolving power (2000-5000)

1 4

1 2

1 0

8

6

4

2

0

Rel

ativ

e In

tens

ity (%

)

8 07 57 06 56 05 55 04 54 03 53 0m / z

C H C H O C H N C H O N

VorführenderPräsentationsnotizenWe can do this because with the AMS we can obtain the MS of the organic aerosols

m/zHydrocarbon-like Organic Aerosols

(Fragmentation pattern similar to that one of long chain hydrocarbons)

Photochemically Aged Organic Aerosols

OrganicOrganic

Aerosol Mass Aerosol Mass SpectraSpectra

fromfrom

dieseldiesel

exhaustexhaust

m/z

OrganicOrganic

Aerosol Mass Aerosol Mass SpectraSpectra

fromfrom

dieseldiesel

exhaustexhaust

Higher contribution of the CHO family to the organic aerosols after 5 hours of aging

AtomicAtomic

ratiosratios

and OM/BC and OM/BC ratiosratios

O/C and OM/OCH/C

OM/OC (POA)= 1.28-1.33(60 km/h) (idle)

VorführenderPräsentationsnotizenfor those people interested in the measurements of organic carbon I think that it is important to say that the om to oc values for POA that I measured were 1.28 and 1.33

ConclusionsConclusions

•

Fresh aerosols from an Euro 3 diesel car consist mainly of BC (OM/BC=0.2-0.3)

•

POA is an Hydrocarbon-like Organic Aerosol

•

Diesel cars can contribute to SOA (30- 80% after 5 hrs of aging)

•

During the aging Organic Aerosols get more oxidized

VorführenderPräsentationsnotizenI have started my talk with this picture and I will conclude with this one as well because I think that my conclusions might be interesting for those people involved in the studies of global warming and health effectsIt is important to learn more about the composition of SOA

http://immagini.p2pforum.it/out.php/i234505_13teschio800.jpg

Thanks toThanks to…………..

M. Heringa, P. M. Heringa, P. DeCarloDeCarlo, T. , T. TritscherTritscher, , E. Weingartner, G. E. Weingartner, G. WehrleWehrle, , R. Richter, A.S.H. R. Richter, A.S.H. PrevotPrevot, , and U. and U. BaltenspergerBaltensperger

Thank you for your attentionVielen Dank für Ihre Aufmerksamkeit

Merci pour votre attention Grazie per la vostra attenzione

http://www.chrismadden.co.uk

roberto.chirico@psi.chroberto.chirico@psi.ch

Filling

the

chamber in ~15 min

Euro 3 diesel

car

running

at 60 km per hour

AgingAging

of of dieseldiesel

exhaustexhaust

in in thethe

PSI PSI smogsmog

chamberchamber

200

150

100

50

0

09:4505.11.2008

10:00 10:15 10:30 10:45 11:00dat

dat

09:4507.11.2008

10:00 10:15 10:30

09:00 09:15 09:30 09:45 10:00

dat

Tem p_051108 (60 km/h) Tem p_171108 (idle) Tem p_071108 (60 km/h) Tem p_211108

200-210 °C

82 °C

Exhaust temperatureExhaust temperature

Diesel Oxidation CatalystDiesel Oxidation Catalyst

the oxidation of NO to NO2 is constrained kinetically at low temperatures and thermodynamically at higher temperatures

1.0

0.8

0.6

0.4

0.2

0.0

OM

/BC

13 012 01101009080Tem p era tu re e xh au st

Idlin g m od e600 R PMC on su m ptio n 0.6 l/h

Direct measurement: Temperature effectDirect measurement: Temperature effect

1 . 2

1 . 0

0 . 8

0 . 6

0 . 4

0 . 2

OM

/BC

543210

A V G _ O M B C _ id le A V G _ O M B C _ 6 0 k m h

0.80+/-0.36

0.44+/-0.20

OM/BCOM/BC

Size distributionSize distribution

2

3

4

56789

100

2

3

4

5

6

Size

[nm

]

20151050

H.A .L .O .(h rs)

2 .0x10 41 .51 .00 .50 .0

dN /d logDp

31-01-2008

idle

3 .0

2 .5

2 .0

1 .5

1 .0

0 .5

0 .0

OM

/BC

1 6 01 4 01 2 01 0 08 06 04 02 00O rg a n ic lo a d in g

O n ly 0 6 0 0 -1 8 3 0 in te rv a ls

O M o v e rB C _ 0 6 0 0 _ 1 8 3 0 O M o v e rB C _ E M P A -S ilk e O M o v e rB C _ S m o g C h a m b e r

OM/BC OM/BC vsvs

OrgOrg

OM/OC OM/OC vsvs

O/CO/C

Diesel fuelsC10-C25 hydrocarbon mixtures

Lubricating oilsC14-C45 hydrocarbon mixtures

OM/OC (C10-C45 long chain alkanes) 1.17 -1.19

VOC/NOVOC/NOXX

ratioratio

2 6 0

2 4 0

2 2 0

2 0 0

1 8 0

1 6 0

1 4 0

1 2 0

1 0 0

8 0

6 0

4 0

2 0

0

ppb

2 01 51 050H . A . L . O . ( h r s )

O z o n e _ M L N O _ M L N O x _ M L

OzonePropene

High NOX

(~NO) conc. from diesel exhaust

OH reacts about 5.5 times more rapidly with NO2

than with an average urban VOC mix

VOC/NOX

ratio needs to be increased

NO2

NO

O

O2

O3

sunTermination

by NOx

Initiation RO :Photolysis of

O , Aldehydes, HONO

x

3

OHHNO3

H

RCH (OH)2

RCH O2 2

HO2

RCH O2

RCO

RCH (ROG)3

CO

RCHO

Terminationby RO + ROx x

H O2 2RCH OOH2

ORCO

RCO2O

PAN'sHO2+

+ HO2

+

NO2

+O2

+

+

+

or Addition

SubstractionH O2

O2++ O2

+ O2

CO2

CO2

+ O2

H O2

HRHR--ToFToF--AMSAMS

(MS mode)(MS mode)

(Jayne et al., 2000; De Carlo et al., 2006)

Turbo Pump (~1E-3 Torr)

Turbo Pump (~1E-8 Torr)

Particle Inlet (1 atm)

AerodynamicLens (2 Torr)

SAMPLING CHAMBER

AERODYNAMIC SIZING

CHAMBER

Thermal Vaporization

(600°C)and

Electron Ionization

(70 eV)

Critical orifice(100 µm) DETECTION

CHAMBER

QuadrupoleMass Spectrometer

e¯

Chopper (150 Hz)

e-

Composition of diesel emissionsComposition of diesel emissions

(Schneider et al., ES&T 2005)

Primary Organic Aerosols (POA)

100-200 nmagglomerated particles

consisting of solid carbonaceous material

with adsorbed organics and sulfates

Composition of the organic fractionComposition of the organic fraction

(Schauer et al., ES&T 1999)

Hundreds of different organic compounds

AldehydesKetonesAlkanesPAHs

TOTAL ORGANICS

8%

4%

1%

4%

1%

0%

42%10%

1%

0%

29%

ALKANESALKENESALKYNESMONOCYCLIC AROMATICPAHsHOPANE AND STERANESALDEHYDESKETONESACIDSTOTAL OTHERSUnresolved Complex Mixture

Diesel particle number concentrationDiesel particle number concentration

THE TOTAL PARTICLE NUMBER HAS

DECREASED WITH NEWER DIESEL

ENGINES

(Burtscher, 2005; Kittelson et al., 1998; www.dieselnet.com)

Older diesel cars

→ high conc of soot particles→ large surface areaNewer diesel cars

→ low conc of soot particles → little surface area → nucleation

more likely

PARTICLE NUMBER IN THE NUCLEI MODE HAS

INCREASED WITH NEWER DIESEL CAR WITH

PARTICLE TRAP

Kelvin effectKelvin effect

The saturation vapor pressure is defined as the equilibrium partial pressure for a plane (flat) liquid surface at a given temperature. If the liquid surface is sharply curved,

such as the surface of a small droplet, the partial pressure required to maintain mass equilibrium is greater than that for a flat surface. The curvature of the surface modifies slightly the attractive forces between surface molecules, so that the smaller the droplet, the easier it is for molecules to leave the droplet surface. To prevent this evaporation-that is, to maintain mass equilibrium-

the partial pressure of vapor surrounding the droplet must be greater than ps.

For pure liquids, the relationship between the saturation ratio required for equilibrium (no growth or evaporation), called the Kelvin ratio Kr, and the droplet size is given the Kelvin equation

Kr=pd/ps=exp(4γM/ρRTd)

γ

=surface

tension

M=molecular

weight

Ρ=density

of the

droplet

liquid

D=Kelvin

diameter, the

diameter

of the

droplet

that

will neither

grow

nor

evaporate

when

the

partial pressure

of vapor

at the

droplet

surface

is

pd

This

equation

defines

a specific

saturation

ratio

required

to mantain

mass equilibrium

for

a given

particle

size

d

WdV

forces

= 1/R6

(Hinds, 1999)

Gas-particle partitioning of organics

Absorption into the aerosol organic matter

6om

0Lom

omP 10pMW

RT760fKγ

=

GasGas--particle partitioningparticle partitioning

(Pankow, Atm

Environ 1994)activitypressure,vapor ,MW

matter organic offraction phase org

∝

ATSP/F

PK =

F (ng/m3) is the particulate-associated concentration of orgTSP is the concentration of the total suspended particulate (µg/m3)A (ng/m3) is the gas-phase concentration of org

omigi ff ,, =0,,, iLomomiomi pf γχ=Ideal conditions: fi=pi RT

pmmoli

Vn

igi

760)/( 3, =

VorführenderPräsentationsnotizenThe gas-particle partitioning of organics can be describe by Absorption into the aerosol organic matter

The absorption coeffcient

(babs

) is defined with Beer–Lambert’s law

where I0

is the intensity of the incoming light and I the remaining light intensity after passing through a medium with the thickness x. The attenuation (ATN) is typically given as percentage values and is defined by the relationship

Aethalometers

measure the light attenuation through a quartz filter matrix where the fiber filter is assumed to act as a perfect diffuse scattering matrix in which the light-absorbing particles are embedded.

According to the Beer–Lambert’s law, the aerosol absorption coefficient of the filtered aerosol particles bATN (or attenuation coefficient) is defined as

where A is the filter spot area (m2), Q the volumetric flow rate

(m3/s)and ΔATN is the change in attenuation during the time interval Δt.It

is well known that bATN

may differ significantly from the true aerosol absorption coeffcient

babs of airborne particles. Therefore, the calibration factors C and R(ATN) are introduced, which can be used to convert aethalometer

attenuation measurements to “real”

absorption coefficients:

Absorption coefficient

(m-1)

C and R describe the two effects which change the optical properties of filter embedded particles with respect to the properties of the same particles in the airborne state

C

= is greater than unity and is caused by multiple scattering of

the light beam at the filter fibers in the unloaded filter. This leads to an enhancement of the optical path and thus to enhanced light absorption of the deposited particles. C depends on the λ. It was experimentally determined during smog chamber studies a C = 2.14±

0.21

Attenuation coefficient (m-1) of the system composed by filter and particles is measured

R(ATN) =

varies with (a) the amount of aerosol particles embedded in the filter and (b) optical properties of the deposited particles. For unloaded filters R is set to unity, i.e. R(ATN = 0) = 1. With the gradual increase in attenuation due to the accumulating particles in the filter the absorbing particles in the filter absorb a higher

fraction of the scattered light which leads to a reduction of the optical path in the filter (R¡1). As a consequence, generally lower attenuation coefficients are measured for higher filter loadings than for lightly loaded filters (Shadowing effect)The aerosol black carbon mass concentration MBC

(gm −3) is related to the absorption and attenuation coefficients bywhere σabs

and σATN

≡ σabs

·C are the mass specific absorption and attenuation cross-sections (m2 g−1), respectively. σATN

strongly depends on the aerosol type and age. They depend on λ.σATN

≡ σabs

·C Mass specific attenuation cross-sections (m2/g). σATN (λ=880 nm)=16.6 m2/g (this

value

is

given

by

the

manual)bATN

and σATN

relate light attenuation to BC mass in the case of filter based

measurement method while babs

and σabs

are used for suspended particle in the air

Q Q vsvs

ToFToF

SpectrometersSpectrometers

––

Time Time resolutionresolution

6≈VV~

D

zeEsmDt

2=

A COMPLETE MASS SPECTRUM IS

ACQUIRED EVERY 12 µs

A MASS SPECTRUM IS SCANNED OVER A MASS

RANGE OF m/z 1-300 WITHIN 300ms

E

QQ ToFToF

m/z=100

Shorter averaging time for representative particle counting statistics

UNIVERSAL AND QUANTITATIVE CHEMICAL ANALYSIS

Positive IonMass

Spectrometry

Vaporizer

e-

ELECTRON EMITTINGFILAMENT

R+

FOCUSED PARTICLE BEAM

FLASHVAPORIZATION

OF NON-REFRACTORYCOMPONENTS (NR)

600 °C ELECTRON IMPACT

IONIZATION

Evaporation/ionizationEvaporation/ionization

chamberchamber

The term ‘non-refractory’

(NR) is defined operationally as those species that evaporate rapidly (

Water H2

O H2

O+

, HO+

, O+

18,

17, 16Ammonium

NH3

NH3+, NH2+, NH+

17, 16, 15Nitrate HNO3

HNO3+, NO2+, NO+

63, 46, 30

Sulfate

H2

SO4 H2

SO4+, HSO3+, SO3

+ 98, 81, 80

SO2+, SO+

64, 48Organic Cn

Hm

Oy

H2

O+, CO+, CO2+

18, 28, 44(Oxygenated) H3

C2

O+,

HCO2+, Cn’

Hm+ 43, 45, ...

Organic

Cn

Hm Cn’

Hm’+

27,29,41,43,55,57,69,71...(hydrocarbon)

Group Molecule/Species

Ion Fragments

Mass Fragments

e-e-

e-

e-

e-

e-

Standard electron impact ionization @ 70 eVEasy to quantify Comparable to the NIST MS libraryEasy to separate inorganic and organic componentsSpeciation of organic composition is challenging

MS Signatures for Aerosol Species IdentificationMS Signatures for Aerosol Species Identification

Terminal velocity is obtained when the gravitational force (FG) is equal and opposite to the drag force

Continuum Regime Aerodynamic Diameter

for irregular particles ofstandard density, dm > dve

> da

Vacuum Aerodynamic Diameter

dm dm vsvs

dvadva

SensitivitySensitivity

The V-Mode

data show detectable signal up to

m/z 1300

The lower sensitivity of W-mode

results in detectable signal up to

m/z 700

(De Carlo et al., 2006)

(Arey

et al., 1989; Reisen

and Arey, 2005; EEA, 2006)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hour of the day

No

scal

e

Oxidant

concentrations

in urban

areas

O3

conc

= 80-150 ppbNOX

conc

= 30-80 µg/m3(Milano 150 µg/m3)

NO3

conc

= 1×1010

molecules/cm3

(nighttime) OH

conc

=5-10×106

molecules/cm3 (summertime)

Oxidant concentrations and diurnal variationOxidant concentrations and diurnal variation

·NO2

+ hν

(λ

Zhang et al., GRL 2007

Worldwide

AMS measurements

show

the

abundance of organics

in the

atmospheric

aerosol

Worldwide

AMS measurements

show

the

abundance of organics

in the

atmospheric

aerosol

Zhang et al., GRL 2007

FractionsFractions

of BC, OM, NO3, SO4 and NH4 of BC, OM, NO3, SO4 and NH4 and fossil and and fossil and nonnon--fossilfossil

contributioncontribution

to EC and OCto EC and OC

Nearly identical composition

Black CarbonOrganic massNitrateSulfateAmmonium

Black CarbonOrganic massNitrateSulfateAmmonium

Z_meanPM10

ECbb4% ECfossil

17%

OCfossil23%

OCnonfossil56%

Z_meanPM10

ECbb4% ECfossil

17%

OCfossil23%

OCnonfossil56%

Zürich

16%30%

14%

6%

34%

Zürich

16%30%

14%

6%

34%

R_mean

ECbb5%

ECfossil17%

OCfossil22%

OCnonfossil56%

R_mean

ECbb5%

ECfossil17%

OCfossil22%

OCnonfossil56%

7%

15%

34%11%

33%

Reiden

7%

15%

34%11%

33%

Reiden

Urban background Highway/rural

13%

60%

13%

7%7%

Zürich (July)

11%

32%

15%

27%

1%

14%

Zürich (January)

Black CarbonOrganic massNitrateSulfateAmmonium

AverageAverage

compositioncomposition

in Zin Züürich in rich in summersummer

and and winterwinter

Lanz et al., ACP (2007)

Organic mass13%

60%

13%

7%7%

Zürich (July)

Black CarbonOrganic massNitrateSulfateAmmonium

OOA: Secondary organic aerosol

HOA: mostly traffic

Chemical Chemical compositioncomposition

in Zin Züürich rich summersummer

andand

Z_meanPM10

ECbb4% ECfossil

17%

OCfossil23%

OCnonfossil56%

Zürich (mean)

Use of AMS analysis :

- wood burning 38%

- HOA 7%

Assumptions :

-

only SOA, HOA and wood burning present

-

OM/OC=2 for wood burning and SOA and OM/OC=1.2 for HOA

-

RESULT : SOAnonfossil: 69% SOAfossil: 31%

(biomass burning)

38%

7%17%

38% Wood burning

Traffic

Secondary(fossil)Secondary(non-fossil)

81%

19%

EC (fossil)

EC (non-fossil)

OM

EC

CarbonCarbon

apportionmentapportionment

usingusing

14C 14C analysisanalysis EstimationEstimation

of fossil and of fossil and nonnon--fossilfossil

SOA SOA contributioncontribution

InorganicsInorganics--S.CS.C..

60 km/h

date_60 OM/BC CO/NOx CO/CO2 OM/(BC*CO2) NO/NOx

110408 0.413 0.254652 0.00050322 0.004945473 0.982716109

71108 0.397 0.025746 0.00010761 0.005113857 0.899252778

211108 0.18 0.012236 3.1328E-05 0.00149138 0.922717961

70109 0.201 0.044092 0.00010491 0.001052584 0.938656715

90408 1.2612 0.691773 0.00152673 0.019011913 0.954776135

51108 0.5089 0.00078636

Idle

date_idle OM/BC_idle CO/Nox_idle CO/CO2_idle OM/(BC*CO2)_idle NO/NOx_idle

100308 0.176 0.275182 0.00271439 0.003667389 0.900077229

40408 0.304 0.249277 0.00247813 0.00452191 0.904475671

171108 0.102 0.232615 0.00248073 0.002273959 0.940398773

1 0 0

8 0

6 0

4 0

2 0

0

org

9 : 4 5 A M4 / 3 / 2 0 0 9

9 : 5 0 A M 9 : 5 5 A M 1 0 : 0 0 A M 1 0 : 0 5 A M 1 0 : 1 0 A M

d a t

5 0 0

4 0 0

3 0 0

2 0 0

1 0 0

0

BC

0 . 4

0 . 2

0 . 0

OM

/BC

1 . 0

0 . 8

0 . 6

0 . 4

0 . 2

0 . 0

Frac

tion

9 : 5 0 A M4 / 3 / 2 0 0 9

9 : 5 5 A M 1 0 : 0 0 A M 1 0 : 0 5 A M 1 0 : 1 0 A M

D a t e a n d T i m e

M F _ P A H M F _ C h l M F _ N H 4 M F _ N O 3 M F _ S O 4 M F _ B C M F _ O r g

HDDVHDDV

0.4

0.3

0.2

0.1

0.0

2:05 PM4/2/2009

2:10 PM 2:15 PM 2:20 PM 2:25 PM 2:30 PM 2:35 PM

dat

2:35 PM4/8/2009

2:40 PM 2:45 PM 2:50 PM 2:55 PM 3:00 PM 3:05 PM

dat

20

15

10

5

0

2:00 PM 2:05 PM 2:10 PM 2:15 PM 2:20 PM 2:25 PM 2:30 PM 2:35 PM

dat

O MoverBC_090402_1 (HD DV) O MoverBC_090406_3 (HD DV) O MoverBC_090408_3 (Diesel-E3-10 ppm) org_090408_3 org_090402_1 org_090406_3

60 km/h 90 km/h

HDDV HDDV vsvs

Diesel E3 passenger carDiesel E3 passenger car

DPM DPM compositioncomposition

1.0

0.8

0.6

0.4

0.2

0.0

Frac

tion

4:00 PM4/16/2009

4:05 PM 4:10 PM 4:15 PM

Date and Time

MF_PAH MF_Chl MF_NH4 MF_NO3 MF_SO4 MF_BC MF_Org

Diesel Euro 4

1.0

0.8

0.6

0.4

0.2

0.0

Frac

tion

4:40 PM4/8/2009

4:45 PM 4:50 PM 4:55 PM

Date and Time

MF_PAH MF_Chl MF_NH4 MF_NO3 MF_SO4 MF_BC MF_Org

Diesel Euro 3

E4 E4 gasolinegasoline

carcar

60

50

40

30

20

10

0

11:1520.04.2009

11:30 11:45 12:00

dat

60

50

40

30

20

10

0

10

8

6

4

2

0

Foliennummer 1Why are we interested in aerosol particles ?Diesel passenger cars�Dilution effect on PM massPrimary and Secondary organic aerosolsSet up for smog chamber experimentsFoliennummer 7Characteristic aging experiment �of diesel exhaustFoliennummer 9SOA contribution to total organic massOrganic Aerosol Mass SpectraOrganic Aerosol Mass Spectra from diesel exhaustOrganic Aerosol Mass Spectra from diesel exhaustAtomic ratios and OM/BC ratiosConclusionsThanks to…….Foliennummer 17Foliennummer 18Foliennummer 19Foliennummer 20Foliennummer 21Foliennummer 22Size distributionFoliennummer 24OM/OC vs O/CVOC/NOX ratioHR-ToF-AMS (MS mode)Composition of diesel emissionsComposition of the organic fractionDiesel particle number concentrationKelvin effectFoliennummer 32Foliennummer 33Q vs ToF Spectrometers – Time resolutionFoliennummer 35Foliennummer 36Foliennummer 37SensitivityOxidant concentrations and diurnal variationFoliennummer 40Worldwide AMS measurements show the abundance �of organics in the atmospheric aerosolFoliennummer 42Foliennummer 43Chemical composition in Zürich summer andFoliennummer 45Inorganics-S.C.Foliennummer 47Foliennummer 48DPM compositionE4 gasoline car