简介：Theprocessofionheatingbyamonochromaticobliquelypropagatinglow-frequencyAlfvenwaveisinvestigated.Thisprocesscanberoughlydividedintothreestages:atfirst,theionsarepickedupbytheAlfvenwaveinseveralgyro-periodsandabulkvelocityinthetransversedirectionisachieved;then,theionsarescatteredinthetransversedirectionbythewave,whichproducesphasedifferencesbetweentheionsandleadstoionheating,especiallyintheperpendiculardirection;andfinally,theionsarestochasticallyheatedduetothesubcyclotronresonance.Inthispaper,withatestparticlemethod,theefficiencyandtimescaleoftheionstochasticheatingbyamonochromaticobliquelypropagatinglow-frequencyAlfvenwavearestudied.Theresultsshowthatwiththeincreaseoftheamplitude,frequency,andpropagationangleoftheAlfvenwave,theefficiencyoftheionstochasticheatingincreases,whilethetimescaleoftheionstochasticheatingdecreases.Withtheincreaseoftheplasmabetaβ,theionsarestochasticallyheatedwithlessefficiency,andthetimescaleincreases.Wealsoinvestigatetheheatingofheavyionspecies(He2+andO5+),whichcanbeheatedwithahigherefficiencybytheobliqueAlfvenwave.

简介：Detailedanalysisofthelowfrequencyinstabilityisperformedinalinearmagnetizedsteadystateplasmadevice.Identificationandmodificationoftheinstabilityarepresented.

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简介：ThisworkinvestigatedC2F6/O2/ArplasmachemistryanditseffectontheetchingcharacteristicsofSiCOHlow-kdielectricsin60MHz/2MHzdual-frequencycapacitivelycoupleddischarge.FortheC2F6/Arplasma,theincreaseinthelow-frequency(LF)powerledtoanincreasedionimpact,promptingthedissociationofC2F6withhigherreactionenergy.Asaresult,fluorocarbonradicalswithahighF/Cratiodecreased.Theincreaseinthedischargepressureledtoadecreaseintheelectrontemperature,resultinginthedecreaseofC2F6dissociation.FortheC2F6/O2/Arplasma,theincreaseintheLFpowerpromptedthereactionbetweenO2andC2F6,resultingintheeliminationofCF3andCF2radicals,andtheproductionofanF-richplasmaenvironment.TheF-richplasmaimprovedtheetchingcharacteristicsofSiCOHlow-kfilms,leadingtoahighetchingrateandasmoothetchedsurface.

简介：Ahybridmodelisusedtosimulatethecharacteristicsofacollisionalsheathinacapacitivelycoupledplasma(CCP)drivenbyadualfrequencysourceincludingaRFandapulsedcurrentsourceappliedtothesameelectrode.Thehybridmodelincludesafluidmodelusedtosimulatethecharacteristicsofthecollisionalsheath,andaMonte-Carlo(MC)methodtoobtainbothionenergyandionangulardistributions(IEDsandIADs)impingingonthesubstrate.Theeffectsofthelowfrequencyofthepulsedsourceandthegaspressureonthecharacteristicsofthesheath,aswellastheIEDsandIADs,arestudied.Theresultsshowthattheratioofpulse/RFfrequencyandthegaspressurearecrucialforthecharacteristicsofthesheathandtheIEDs.TheIADsaresignificantlymoresensitivetothegaspressure.

简介：Basedonthefundamentalideasconcerningmicrowaveattenuationinplasma,weobtainanewexpressionoftransmissionattenuationofmicrowavesasafunctionoftheincidentwavefrequency.Andwithreasonablehypothesis,analyticalformsoftheelectrondensityandtheelectron-neutralcollisionfrequencyarederivedfromtheequationsofthetransmissionattenuationofmicrowavesattwonearfrequencies.Thismethodgivesaneffectiveandeasyapproachtodiagnosetheunmagnetizedplasma.

简介：Thedischargeoperationregimeofpulsemodulatedatmosphericradiofrequency(RF)glowdischargeinheliumisinvestigatedonthedutycycleandfrequencyofmodulationpulses.Thecharacteristicsofradiofrequencydischargeburstintermsofbreakdownvoltage,alpha(α)-gamma(γ)modetransitionvoltageandcurrentaredemonstratedbythedischargecurrentvoltagecharacteristics.TheminimumbreakdownvoltageofRFdischargeburstwasobtainedatthedutycycleof20%andfrequencyof400kHz,respectively.Theα-γmodetransitionofRFdischargeburstoccursathighervoltageandcurrentbyreducingthedutycycleandelevatingthemodulationfrequencybeforetheRFdischargeburstevolvingintotheignitionphase,inwhichtheRFdischargeburstcanoperatestablyintheγmode.ItproposesthattheintensityandstabilityofRFdischargeburstcanbeimprovedbymanipulatingthedutycycleandmodulationfrequencyinpulsemodulatedatmosphericRFglowdischarge.

简介：Inatmosphericradio-frequency(rf)discharges,theplasmaparameters,suchaselectrondensity,sheaththicknessandsheathvoltage,arenoteasytobeprobedexperimentally,whiletheelectricalcharacteristics,suchasimpedance,resistanceandreactance,arerelativelyconvenienttobemeasured.Inthispaperwepresentedasimpletheoreticalmodelderivedfromthefluiddescriptionofgeneratedplasmaswithoutconsideringthecircuitmodel,toinvestigatetherelationshipbetweentheplasmaimpedanceandplasmaparameters.Byintroducingarelaxationfrequency,theplasmaimpedancecouldbepredictedbyformulaspresentedinthisstudy,andthemeanelectrondensityandsheaththicknesscanalsobecalculatedfromthemeasuredorsimulatedimpedanceandreactance,respectively.

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简介：ByECHunderasteadyB_vfield,aclosedfieldequilibriumofalowaspectratioaslowasR/a=1.4isspontaneouslyformedintheLATEdevice.Afterthespontaneousformation,theplasmacurrenthasincreasedfurtheruptoI_P=7.2kAby2.45GHz,30kWandI_P=11kAby5GHz,120kW,byincreasingthemicrowavepowerwithaslowrampofB_vfortheequilibriumoftheplasmaloopatlargercurrents.Bothamountto12%ofthetotaltoroidalcoilcurrent.ECH/ECCDat2udharmonicresonanceofEBWsupportstheplasma.Anoutlineofthetheoreticalconsiderationsfortheformationprocessispresented.

简介：Thekillinglogarithmsindexinkillingavegetativeforminanexplosureofabout90sandasporeinanexplosureofabout120s,byusingalow-temperatureplasmaproducedbydielectricbarrierdischarge(DBD),reached5.Thespeedinkillingthestrainstested,byusingalow-temperatureplasma,wasthehighestwithE.Coli,thenS.AureusandB.Subtilisvarnigerspore.Theresultsofthescanningelectronmicroscopeshowedthatthelow-temperatureplasmadestroyedtheouterstructureofthebacteriaandthatthevegetativeformwasmoresusceptibletotheinactivationeffectofthelow-temperatureplasmathanwasthespore.Thisindicatedthattheeffectsofthehighvoltageandhighvelocityparticleflow,inplasma,penetratingthroughtheouterstructureofthebacteriamightplayadominantroleduringtheinactivationofthebacteria.

简介：Thedual-frequencycapacitivelycoupledplasma(DF-CCP)withinductiveenhancementsystemisanewlydesignedplasmareactor.Differentfromtheconventionalinductivelycoupledplasma(ICP)reactors,nowaradiofrequency(rf)powerisconnectedtoanantennaplacedoutsidethechamberwithaone-turnbarecoilplacedbetweentwoelectrodesinDF-CCP.Thispapergivesadetaileddescriptionofitsstructure.Moreover,investigationsonsomecharacteristicsofdischargesinthisapparatusweremadeviaaLangmuirprobe.

简介：Azero-dimensionalmodelwhichincludes56speciesofreactantsand427reactionsisusedtostudythebehaviorofchargedparticlesinatmosphericplasmaswithdifferentionizationdegreesatlowaltitude(near0km).TheconstantcoefficientnonlinearequationsaresolvedbyusingtheQuasi-steady-stateapproximationmethod.Theelectronlifetimesareobtainedforafterglowplasmawithdifferentinitialvalues,andthetemporalevolutionsofthemainchargedspeciesarepresented,whicharedominantinreactionprocesses.Theresultsshowthattheelectronnumberdensitydecaysquickly.Thelifetimesofelectronsareshortenedbyabouttwoorderswithincreasingionizationdegree.Electronsthenattachtoneutralparticlesandproducenegativeions.Whentheinitialelectrondensitiesareintherangeof1010～1014cm3,thenegativeionshavesufficientlyhighdensitiesandlonglifetimesforairpurification,disinfectionandsterilization.Electrons,O2,O4,CO4andCO3arethedominantnegativespecieswhentheinitialelectrondensityne0≤1013cm3,andonlyelectronsandCO3areleftwhenne0≥1015cm3.N+2,N+4andO+2aredominantinthepositivechargesforanyionizationdegree.Otherpositivespecies,suchasO+4,N+3,NO+,NO+2,Ar+2andH3O+·H2O,aredominantonlyforacertainionizationdegreeandinacertainperiod.

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：Alowpoweratmosphericpressureplasmajetdrivenbya24kHzACpowersourceandoperatedwithaCH4/airgasmixturehasbeeninvestigatedbyopticalemissionspectrometer.Theplasmaparametersincludingtheelectronexcitationtemperature,vibrationaltemperatureandrotationaltemperatureoftheplasmajetatdifferentdischargepowersarediagnosedbasedontheassumptionthatthekineticenergyofthespeciesobeystheBoltzmanndistribution.TheelectrondensityatdifferentpowerisalsoinvestigatedbyHβStarkbroadening.Theresultsshowthattheplasmasourceworksundernon-equilibriumconditions.Itisalsofoundthatthevibrationaltemperatureandrotationaltemperatureincreasewithdischargepower,whereastheelectronexcitationtemperatureseemstohaveadownwardtrend.Theelectrondensityincreasesfrom0.8×1021m-3to1.1×1021m-3whenthedischargepowerincreasesfrom53Wto94W.

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简介：TiBCNnanocompositecoatingsweredepositedoncementedcarbideandSi（100）byacathodearcplasmasystem,inwhichTiB2cathodeswereusedinmixturegasesofN2andC2H2.X-raydiffractionshowsthatTiB2andTi2B5peaksenhanceatlowflowratesofC2H2,buttheyshrinkwhentheflowrateisover200seem.AnincreaseofdepositionratewasobtainedfromdifferentTiBCNthicknessesforthesamedepositiontimemeasuredbyscanningelectronmicroscopy.Atomicforcemicroscopyshowsthatthesurfaceroughnessesare10nmand20nmatC2H2flowratesof0-100sccmandof150-300sccm,respectively.HighresolutiontransmissionelectronmicroscopyandX-rayphotoelectronspectroscopyshowthatthecoatingsconsistofnanocrystalphasesTi2B5,TiB2andTiN,andamorphousphasecarbonandBN.Theaveragecrystalsizesembeddedintheamorphousmatricesare200nmand10nmatC2H2flowratesof200sccmand300sccm,respectively.InRamanspectra,theD-andG-bandsincreasewithC2H2flowsatlowflowrates,butweakenathighflowrates.Themicrohardnessofthecoatingsdecreasesfrom28.6GPato20GPaastheC2H2increasesfrom0sccmto300sccm,andtheball-on-diskmeasurementshowsadramaticdecreaseofthefrictioncoefficientfrom0.84to0.13.ThereasonforthereducedhardnessandfrictioncoefficientwiththechangeofC2H2flowratesisdiscussed.

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