简介:Anumericaltwo-fluidsimulationofthenon-ionizedradiofrequency(rf)sheathmodel,hasbeencarriedout.Thismodelis'global'andthusapplicabletothesheath,pre-sheathandplasmaregions,Inthemodelallvariablesintheionforcebalanceequation,includingtheelectricalforce,ionpressureandneutralparticlefriction,areconsidered.Themodelissolvedthroughafinitedifferenceschemeandsheathcharacteristicsareobtained.Theeffectsoftheiontemperatureonboththecollisionlessandcollisionalsheathcharacteristicsarediscussed.Thenitisconcludedthat1)themodelisinagoodagreementwithBohmTheorem;2)theiontemperaturehassignificanteffectsontherfsheathcharacteristics.Theeffectsarefarmoresignificantonacollisionalrfsheaththanonacollisionlesssheath.
简介:Characteristicsofiontemperaturemeasuredwithcharge-exchangerecombinationspectroscopy(CXRS)werestudiedinOhmic,lower-hybrid-wave(LHW)drivenandion-cyclotron-resonance-frequency(ICRF)heatedplasmasinHT-7.TheresultsindicatethatthecentraliontemperatureTi0followstheone-thirdpowerlawintheproductofcentralline-averageddensityneandplasmacurrentIpinOhmicdischargesandisthereforeconsistentwiththeArtsimovichscalinglawTi0=K·(Ip·Bt·ne·R2)1/3.ItisshownthatthereisanappreciableincreaseofiontemperatureduringtheoperationwithbothLHWandICRFandthattheincrementofiontemperatureinthoseshotsismainlyduetotheenergytransferviacollisionsbetweenionsandelectronsratherthatbydirectheatingoftheions.
简介:Thedependencesofradiationinduceddefectsonirradiationtemperatureupto700℃at15dpaandonirradiationdoseupto85dpaatroomtemperaturehavebeeninves-tigatedbytheheavyionirradiationandthepositronannihilationlifetimespectroscopyfortheCLAM.Avoidsizepeakisobservedat~500℃wherethevacancyclustercontains9vacanciesandhasanaveragediameterof0.59nm.Thesizeofthevacancyclustersincreaseswiththeincreaseofirradiationdoseatroomtemperature,andthevacancyclusterat85dpaconsistsof9vacanciesandreachesasizeof0.60nmindiameter.TheabsolutevaluesofthevoidsizeatthepeakandtheincreaseofvoidsizewithdoseintheCLAMsteelarenegligiblecomparedtothoseofthenormalstainlesssteels,indicatingthattheCLAMsteelhasgoodradiationresistantproperty.
简介:Moleculardynamicssimulationswereperformedtostudytheinteractionbetweenatomichydrogenandsiliconcarbide.Inthepresentstudy,wefocusontheeffectofthesurfacetemperatureonHinteractingwithsiliconcarbide.ThesimulationresultsshowthattheretentionofHatomsinthesampledecreaseslinearlywithincreasingsurfacetemperature.ThedepthprofileanalysisshowsthatthesampleismodifiedbyHbombardment,andthedensityofHatomsisgreaterthanthoseofSiandCatomsneartheinterfaceregionbetweentheH-containingregionandthebulk.However,nearthesurfaceregionthedensitiesofH,SiandCatomsarealmostequivalent.Inthemodifiedlayer,thebondsconsistofSi-CandSi-HandC-H.ThefractionofSi-Cbondsisthegreatest.OnlyafewC-Hbondsarepresent.
简介:AnexperimentwasperformedontheShenguangIIIprototypelaserfacilitytocontinuethestudyonhohlraumradiationsourcewithapproximatelyconstantradiationtemperatureusingacontinuouslyshapedlaserpulse.Aradiationsourcewithaflattoptemperatureofabout130eVthatlastedabout5nswasobtained.Thepreviousanalyticaliterationmethodbasedonpowerbalanceandself-similarsolutionofablationwasmodifiedtakingintoaccounttheplasmamovementsanditwasusedtodesignthelaserpulseshapeforexperiment.Acomparisonbetweenexperimentalresultsandsimulationispresentedandbetteragreementwasachievedusingthemodifiedmethod.Furtherimprovementsarediscussed.
简介:Thekillinglogarithmsindexinkillingavegetativeforminanexplosureofabout90sandasporeinanexplosureofabout120s,byusingalow-temperatureplasmaproducedbydielectricbarrierdischarge(DBD),reached5.Thespeedinkillingthestrainstested,byusingalow-temperatureplasma,wasthehighestwithE.Coli,thenS.AureusandB.Subtilisvarnigerspore.Theresultsofthescanningelectronmicroscopeshowedthatthelow-temperatureplasmadestroyedtheouterstructureofthebacteriaandthatthevegetativeformwasmoresusceptibletotheinactivationeffectofthelow-temperatureplasmathanwasthespore.Thisindicatedthattheeffectsofthehighvoltageandhighvelocityparticleflow,inplasma,penetratingthroughtheouterstructureofthebacteriamightplayadominantroleduringtheinactivationofthebacteria.
简介:TherearetwotpyesofphasetransformationsinFe-MnandFe-Mn-Sialloyswhenthetemperatureisdecreased,γ(fcc)→ε(hcp)martensitictransformation(MT)andparamagnetic-antiferromagnetictransition(AMT)ofγphase.Fromthethermodynamicpointofview,theformerusuallyappearsinaslightlyhighertemperaturerangethanthelatterbecauseifisgenerallyacceptedthatthemagnetictansitionhasasuppressingeffectonthethermallyinducedεmartensite(Satoetal.,1984.,BogachevandZvigintzeva,1976;Murakamietal.,1987:Yangetal.,1992)GartsteinandRobinkin(1979)eventhoughtthattheγ-εtransformationshouldbeterminatedbelowNeeltemperature(TN)duetothedecreaseoffreeenergyarisingfromtheAMTofγphase.However,someexperimentalresultshaeindicatedtheformationofεphasebelowT(LiandWayman,1994:Fujimori.1966).Inthepresentwert.thebehavorofγ-εtransformationbelowTNwasfurtherinvestigatedbyclectricalresistancemeasurements.
简介:Dependenceofthecurrent-voltagecharacteristicsofanon-transferredDCcascadedplasmatorchusedfornanoparticlesynthesis,ontheplasmacurrentandtheplasmaargongasflowratearereportedinthispaper.Thepotentialstructureinsidethetorchanditsdependenceontheplasmacurrentandgasflowratearealsoinvestigated.Thearcvoltageisseentoexhibitnegativecharacteristicforacurrentbelow150Aandpositivecharacteristicabovethatcurrentvalue.Thevoltagedropneartheelectrodesisfoundtodecreasewiththeincreaseinplasmacurrent.25%ofthetotalvoltageisdroppednearthecathodeataplasmacurrentof50Aandaargonplasmagasflowrateof10literperminute(LPM),anditdecreasesto12%withthecurrentincreasingto300A,andto17%withagasflowrateof25LPM.Thevariationinthetorchefficiencywiththegasflowrateandplasmacurrentisalsoreported.Theefficiencyofthetorchisfoundtobebetween36%and48%.Inaddition,theplasmagastemperatureatvariouspositionsofthereactorandfordifferentcurrentsandvoltagesaremeasuredbycalorimetricestimationwithaheatbalancetechnique.
简介:Anovelatmosphericplasmadevicedevelopedinthispaper,whichismoreeffectiveandconvenienttostudytheplasma-initiatedpolymerization(PIP)thanconventionalsetup.Thestructureandmechanismofthedeviceisintroduced.Someplasma-initiatedpolymerizationexperimentsarecarriedoutonthedevice,andtheconversionofAA(Acrylicacid)andAM(Acrylamide)atmospheric(N2)plasmapolymerizationarerespectively89%and94%after120hpostpolymerization,wherebyIRspectraoftheproduct(AA,AM).OurPIPresultareconfirmed.
简介:AnX-rayradiationsourcewithapproximatelyconstantradiationtemperatureisrealizedbyirradiatinggoldenhohlraumwithashapedlaserpulse.Asimpletheoreticalmodelbasedonpowerbalanceisusedtodesigntheshapeofthedrivelaserpulse.ExperimentsarecarriedoutontheShenguangIIIprototypelaserfacility,andtheexperimentalresultsarepresentedforradiationsourceswiththeflat-toplastingabout2.5nsattwodiferentpeaktemperaturesofabout150eVand170eV,respectively,includingthetimehistoriesofthetemperatures,theshapesofthedrivelaserpulsesandthetimeintegratedradiationspectra.Thevalidityofthemodelandpossibleimprovementsarediscussed.
简介:Thebehaviorofargonplasmadrivenbynanosecondpulsedplasmainalow-pressureplasmareactorisinvestigatedusingaglobalmodel,andtheresultsarecomparedwiththeexperimentalmeasurements.ThetimeevolutionofplasmadensityandtheelectronenergyprobabilityfunctionarecalculatedbysolvingtheenergybalanceandBoltzmannequations.Duringandshortlyafterthedischargepulse,theelectronenergyprobabilityfunctioncanberepresentedbyabi-Maxwelliandistribution,indicatingtwoenergygroupsofelectrons.Accordingtotheeffectiveelectrontemperaturecalculation,wefindthattherearemorehigh-energyelectronsthatplayanimportantroleintheexcitationandionizationprocessesthanlow-energyelectrons.Theeffectiveelectrontemperatureisalsomeasuredviaopticalemissionspectroscopytoevaluatethesimulationmodel.Inthecomparison,thesimulationresultsarefoundtobeinagreementwiththemeasurements.Furthermore,variationsoftheeffectiveelectrontemperaturearepresentedversusotherdischargeparameters,suchaspulsewidthtime,pulserisetimeandgaspressure.
简介:StationarylongpulseplasmaofhighelectrontemperaturewasproducedonEASTforthefirsttimethroughanintegratedcontrolofplasmashape,divertorheatflux,particleexhaust,wallconditioning,impuritymanagement,andthecouplingofmultipleheatingandcurrentdrivepower.Adischargewithalowersinglenulldivertorconfigurationwasmaintainedfor103sataplasmacurrentof0.4MA,q95≈7.0,apeakelectrontemperatureof>4.5keV,andacentraldensityne(0)2.5×1019m-3.Theplasmacurrentwasnearlynon-inductive(Vloop<0.05V,poloidalbeta0.9)drivenbyacombinationof0.6MWlowerhybridwaveat2.45GHz,1.4MWlowerhybridwaveat4.6GHz,0.5MWelectroncyclotronheatingat140GHz,and0.4MWmodulatedneutraldeuteriumbeaminjectedat60kV.Thisprogressdemonstratedstrongsynergyofelectroncyclotronandlowerhybridelectronheating,currentdrive,andenergyconfinementofstationaryplasmaonEAST.Itfurtherintroducedanexampleofintegrated'hybrid'operatingscenarioofinteresttoITERandCFETR.
简介:Theinfluenceontheeffectivenessofsterilizationbylow-temperatureplasmasterilizerCASP-80Awasinvestigatedsoastoprovideatheoreticalbasisforreducingmedicalcostsandachievingidealsterilizationeffectiveness.Toconducttheon-sitesimulationtest,aclinicalmaterialsterilizationtestandatestoftheinfluenceoforganicsubstancewereconducted,theformerbyusingtherepresentativeofBacillusStearothermophilus,preparingthebacteria-contaminatedcarrierthroughpolytetrafluoroethylene(PTFE)simulatedhoseendoscopes,andthelatterbyusingcalfserumastheinfluencefactoroftheorganicsubstance.TheresultsshowthattheCASP-80Alow-temperatureplasmasterilizercouldachieveeffectivesterilizationbyeithertheshort-cycleorthelong-cyclesterilizationmethoddependingondifferentmaterials,apparatus,andextentofcontamination.Theorganicsubstancescouldinfluencetheeffectivenessofsterilizationbythelow-temperatureplasma(H_2O_2)sterilizer.
简介:Inthispaper,aone-dimensionparticle-in-cell(PIC)code(EDIPIC)isemployedtosimulatetheparallel-plateionextractionprocessunderanexternallyappliedelectrostaticfield,focusingontheanalysisoftheinflueneeoftheinitialelectrontemperatureontheextractedionfluxestothemetalplatesduringtheionextractionprocess.Comparedwithpreviouslypublishedresults,theplasmaoscillationsonatimescaleoftheelectronplasmaperiod,andtheexcitationoftheionacousticrarefactionwavesresultingfromtheplasmaoscillationsoriginatingfromboththenegativeandpositiveelectrodes,arestudiedforthefirsttime.Themodelingresultsshowthatboththenegativeandpositiveextractorscancollectionsduetotheplasmaoscillationsandthepropagationoftheionacousticrarefactionwaves.Withtheincreaseoftheinitialelectrontemperatureachievedbykeepingotherparametersunchanged,ontheonehand,boththeionspeedandfluxtothenegativeandpositiveplatesincrease,whichleadstoasignificantdecreaseoftheionextractiontime,whileontheotherhand,theionfluxtothepositiveplateaftertheformationofaChild-Langmuirsheathismuchmoresensitivetoanincreaseoftheinitialelectrontemperaturethanthattothenegativeplate.ThePICsimulationresultsprovideadeeperphysicalunderstandingoftheinfluenceoftheinitialelectrontemperatureonthecharacteristicsoftheentireionextractionprocessinadecayingplasma.
简介:Zn_(1-x)Cu_xOthinfilmsweresynthesizedbytheradiofrequency(RF)magnetronsputteringtechniqueusingaZnOtargetcontainingdifferentpiecesofsmallCu-chips.X-raydiffraction(XRD)andscanningelectronmicroscopy(SEM)wereemployedtoanalyzethecrystallineandmicrostructureofthefihn,andX-rayphotoelectronspectroscopy(XPS)wasusedtoestablishthebondingcharacteristicsandoxidationstatesofcopperinsidetheZnOhost.Roomtemperature(RT)ferromagnetismwasobservedintheZn_(1-x)Cu_xOfilmsbyaQuantumDesignsuperconductingquantmninterferencedevice(SQUID)andthesaturationmagneticmomentofthefilmswasfoundtodecreasewiththeincreaseinCucontent.
简介:Undercoronalconditions,thesteadystaterate-equationsareusedtocalculatetheinter-stagelineratiosbetweenLi-likels22p(2p3/2)→ls22s(2S1/2)andHe-likels2p(1P1)→ls2(1So)transitionsforTiintheelectronictemperaturerangesfrom0.1kevto20keV.Theresultsshowthatthetemperaturesensitivitiesarehigherattheelectronictemperaturelessthan5000eVandthetemperaturesensitivitieswilldecreasewiththeincreaseofelectronictemperature.