Give some examples of Sounds in everyday life. · Physicists at the Argonne Naonal Laboratory are...
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Transcript of Give some examples of Sounds in everyday life. · Physicists at the Argonne Naonal Laboratory are...
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GivesomeexamplesofSoundsineverydaylife.-Speech-Ultrasoundmachineusedtobreakupkidneystonesordestroytumors-Ultrasoundpregnancy-feelasonicboom
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::WhentheboundaryofaWavearefixed,therewillbeatransmiDedwave,aswellasareflectedwave.WhenthesetwowavesinterferewithoneanotherTheygiverisetowhatisknownasastandingwave.TheycanalsobethoughtofasawavewhichoscillateswithrespecttoGme,yethasapeakamplitudethatdoesnotmoveinspace::Nodes
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!::WhentheboundaryofaWavearexfixed,therewillbeatransmiDedwave,aswellasareflectedwave.WhenthesetwowavesinterferewithoneanotherThueygiverisetowhatisknownasastandingwave.TheycanalsobethoughtofasawavewhichoscillateswithrespecttoGmxe,yethasapeakamplitudethatdoesnotmoveinspaceu::NodesItiswellknownthatobjects,allthingsbeingequal,willmovefrom;anareaofhighpressuretolowpressure.::wellthat’sessenGallywhatisthecoreofacousGcallevaGaGon.;Varyingtheshapeofthetransducervoltagewaveformhadasignificanteffectonlayerthickneuss,withasquarewaveformcreaGnguthinner,moredisGnctlauyersthanasinewaveformduetosteeperpressuregradientsatthenodes.AcousGclevitaGonisaphenomenxonwherebypressuuredifferexncesofstaGxonarysoundwavescanbeusedtosuspendsxmallobjectsingasesorfluidssuchasairorwater
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AninteresGngautobiographicalnote:Idon’tknowaboutanyoneelse,asforme,InotoriouslyhadadifficultGmevisualizingstandingwaves.
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::WhentheboundaryofaWavearefixed,therewillbeatransmiDedwave,aswellasareflectedwave.WhenthesetwowavesinterferewithoneanotherTheygiverisetowhatisknownasastandingwave.TheycanalsobethoughtofasawavewhichoscillateswithrespecttoGme,yethasapeakamplitudethatdoesnotmoveinspace::Nodes
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Cytoskeleton:essenGallyaGssuethatconnectsacomplexnetworkoflinkingproteinfilaments,itbringstomindtheimagewhatmostofusarefamiliarwith.CulturesofCellsobviouslyextractedfromthesubject.Thentheusersendsalow-frequencysoundwavethroughthefluid,attherespecGveacousGcallevitaGonfrequency(250kHz,andoncethecellsarelevitatedintoastableposiGon,anotherultrasonicwavecanbeemiDed,andessenGallyan“ultrasound”canbetaken,wellyoumayask,welljermaine,howisthisimportant.Wellitwouldallowustostudythecellsinanenvironmentmoresimilartooneinvivo(onethatwouldtakeplacewithintheorganism),alsodifferentdensiGesreacttoultrasounddifferently,whatgroupofcellsUltrasonicsignalsfromtheseculturescanbeproblemaGcduetotheinterferenceofreflecGonsfromtheculture-platewell.Thecellstructureisalsoo`endeformedfromitsnaGvestateduetoadhesiontothecultureplate.
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Humanembryonickidneycells(HEK)
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Achievingdiametersbetween9-15microns
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::WhentheboundaryofaWavearefixed,therewillbeatransmiDedwave,aswellasareflectedwave.WhenthesetwowavesinterferewithoneanotherTheygiverisetowhatisknownasastandingwave.TheycanalsobethoughtofasawavewhichoscillateswithrespecttoGme,yethasapeakamplitudethatdoesnotmoveinspace::Nodes
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A`ertheacousGclevitatorisadjustedtoaproperstate,weuGlizeatweezercarefullytointroducetheanimalsintothelevitaGonposiGon.Figure1showsthelevitaGonprocessofanant,aladybug,andayoungfishinair.SincethelongitudinalcomponentoftheacousGcradiaGonforceFzismuchlargerthanthelateralcomponentsFr,theseanimalsareusuallylevitatedwiththelargestcrosssecGonoftheirbodiesperpendiculartothereflector-emiDeraxis,soastostabilizetheirposture.Theantisusuallylevitatedwithapostureasifitis“crawling”intheairFig.1a.SomeGmes,itstruggledtoescapefromtheconstraintofacousGcradiaGonforcebyrapidlyflexingitslegsFig.1b.However,itfailedbecauseitslegscanobtainliDlecounterforcefromtheair.ThepostureofthelevitatedladybugissimilartothatwhenitstandsorcrawlsonthegroundFig.1c.WecanalsoplacetheladybugintothelevitaGonposiGonwithitsbackdownwardandbellyupward.Inthiscase,theladybugcanhardlyturnitsbodyoverbyitself.Liketheant,theladybugaDemptedtoescapefromthelevitaGonforcetoo.It
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PhysicistsattheArgonneNaGonalLaboratoryareusingsoundwavestolevitateindividualdropletsofsoluGoncontainingpharmaceuGcalstoimprovedrugdevelopment.Drugsfallinto2categories:Amorphousandcrystalline.Amorphousdrugsaremoreefficientlyabsorbedbythebodythantheircrystallinecousinsduetotheirhighersolubilitywhichimpliesthatalowerdosecanbeused.WhensoluGonareevaporatedinavessel,theyaremuchmorelikelytosolidifyinacrystallineform.Thustopreventthisfromhappening,thesoluGonneedtobeevaporatedwithouttouchinganysurfaces.ThisiswhereAcousGclevitaGoncomesin.AcousGclevitaGonisusedtoevaporatesoluGonswithoutallowingthemtocrystallize.
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thisismoreofabonusfeaturethantheactualpresentaGon,butIdon’twanttonotgivecredit.
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