学科分类
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160 个结果
  • 简介:Theβ-decaysofneutron-richcarbon,nitrogenandfluorineisotopeshavebeensys-tematicallystudiedusingtheOXBASHshellModel.Inthepsd,spsdandspsdpfmodelspace,weusetheWBPinteractiontocalculatethehalf-livesandneutronemissionprobabilitiesofneutron-richcarbonandnitrogenisotopes,respectively.WiththeUSD(W)andCWinteractions,wecalculatethehalf-livesandneutronemissionprobabilitiesofneutron-richfluorineisotopeinthesdmodelspace,respectively.Thecalculatedhalf-livesandneutronemissionprobabilitiesrepro-ducerecentexperimentaldataverywell.Itseemstoshowthattheparticlesoftheneutron-richcarbonandnitrogenisotopesaremainlyexcitedinthespsdspace.Theβ-decayof21Ntotheneutronboundstatesin21Oismostlythefirstforbiddentransitionwhichmakestheneutronemissionprobabilityincrease.Thetheoreticalcalculationofβ-decayof25Fto25NewithCWinteractionshowsthatCWinteractionisbetterthanUSDinteraction.

  • 标签: 丰中子核 衰变 氮同位素 中子发射 模型空间 半衰期
  • 简介:Theelectrostaticsheathwithacylindricalgeometryinanion-electronplasmaisinvestigated.AssumingaBoltzmannresponsetoelectronsandcoldionswithbulkflow,itisshownthattheradiusofthecylindricalgeometrydonotaffectthesheathpotentialsignificantly.Wealsofoundthatthesheathpotentialprofileissteeperinthecylindricalsheathcomparedtotheslabsheath.Thedistinctfeatureofthecylindricalsheathisthattheiondensitydistributionisnotmonotonous.Thesheathregioncanbedividedintothreeregions,twoascendantregionsandonedescendantregion.

  • 标签: 等离子体护层 离子-电子等离子体 静电圆柱体护层 边界条件
  • 简介:Thegenerationofplasmawhichcanabsorbmicrowavesiscurrentlyaresearchtopicofinterest.Thiskindofplasmaisoftenproducedbythedischargeorelectron-beamimpactofnoblegases.Inthispaperanalternaticeapproach,combustionplasma,isstudied.Theplasmaisproducedbycombustingsolidgrainspreparedspecially.Sixgroupsofpowdersweremadeandusedtogeneratetheplasma.Thetransmissivityofthewaveinplasmawasmeasuredbyemployingamicrowavescalarnetworkanalysersystem.Inaddition,theelectrondensityandthecollisionfrequencyoftheplasmawereexaminedbymicrowavedouble-frequencydiagnosis.Themeasurementresultsshowedthattheplasmacouldabsorbmicrowavesremarkablywithanaveragetransmissionattenuationbeingmorethan18dBinafrequencyrangeof2GHzto15GHz.Thediagnosisindicatedthattheelectrondensityoftheplasmavariedfrom10~(17)m~(-3)to10~(19)m~(-3)andthecollisionfrequencywasabout5×10~(10)s~(-1).

  • 标签: 碰撞等离子体物理 微波 相互作用 吸收
  • 简介:Plasmasourceperformanceparameters,includingplasmaejectiondensityandvelocity,greatlyaffecttheoperationofashort-conduction-timeplasmaopeningswitch(POS).Inthispaper,theplasmasourceusedinthePOSofQiangguangIgeneratorischosenasthestudyobject.AtfirstthePOSworkingprocessisanalyzed.TheresultshowsthattheopeningperformanceofthePOScanbeimprovedbyincreasingtheplasmaejectionvelocityanddecreasingtheplasmadensity.Theinfluenceofthecableplasmagunstructureandnumberontheplasmaejectionparametersisexperimentallyinvestigatedwithtwochargecollectors.Finallyasemi-empiricalmodelisproposedtodescribetheexperimentalphenomenon.

  • 标签: 等离子体断路开关 等离子体源 性能参数 导通时间 等离子体密度 等离子体喷射
  • 简介:Opticalemissionspectroscopy(OES)wasappliedforplasmacharacterizationduringtheerosionofasphaltenesubstrates.Anamountof100mgofasphaltenewascarefullyappliedtoanelectrodeandexposedtoair-plasmaglowdischargeatapressureof1.0Torr.Theplasmawasgeneratedinastainlesssteeldischargechamberbyanacgeneratoratafrequencyof60Hz,outputpowerof50Wandagasflowrateof1.8L/min.Theelectrontemperatureandiondensitywereestimatedtobe2.15±0.11eVand(1.24±0.05)×1016m-3,respectively,usingadoubleLangmuirprobe.OESwasemployedtoobservetheemissionfromtheasphalteneexposedtoairplasma.BothmolecularbandemissionfromN2,N+2,OH,CH,NH,O2aswellasCN,andatomiclightemissionfromVandHγwereobservedandusedtomonitortheevolutionofasphalteneerosion.Theasphalteneerosionwasanalyzedwiththeaidofascanningelectronmicroscope(SEM)equippedwithanenergydispersiveX-ray(EDX)detector.TheEDXanalysisshowedthatthetimeevolutionofelementsC,O,SandVweresimilar;andthechemicalcompositionoftheexposedasphaltenesremainedconstant.Particlesizeevolutionwasmeasured,showingamaximumsizeof2307μmafter60min.Thisbehaviorismostlikelyrelatedtoparticleagglomerationasafunctionoftime.

  • 标签: 空气等离子 发射光谱仪 沥青基材 侵蚀过程 离子反应 表面分析
  • 简介:一个表面波浪激动的血浆列能充当一条血浆天线。实验被执行学习电流和传导性如此的一条血浆天线的分布,领域,功率模式,择向性和效率。另外,一条相等的金属性的铜天线被建立,它的天线参数与血浆天线的相比。我们的调查结果显示在血浆天线的泛音的力量内容是与铜天线相比同样突出的更多(它仅仅产生基本频率)。然而,为两条天线的力量模式是相当类似的。在血浆天线的领域里关于泛音的产生提供更质的理解,双性人光谱的分析被执行在当前的变化学习非线性的相互作用。血浆天线的一些特定的特征在我们的学习被调查,它可以关于常规金属性的天线提高血浆天线的申请前景。

  • 标签: 表面等离子体波 天线参数 实验 等离子体天线 非线性相互作用 谐波功率
  • 简介:Bohmcriterioninamagnetizedplasmasheathisinvestigatedwithafluidmodel.Theupperandlowerlimitsforthesheathcriterionindifferentstatesofappliedmagneticfieldarestudied.TheresultsfromnumericalsimulationrevealthatthemagneticfieldaffectssignificantlytheionMachnumber.ThevariationoftheionMachnumberwiththeincidentangleoftheionsisalsopresented.

  • 标签: 等离子体鞘层 玻姆 磁化 判据 流体模型 外加磁场
  • 简介:Hugoniotrelationsofatwo-dimensionalaxialshockwithcurrentandmagneticfieldinacylindricalshocktubewereinvestigatedbyanumericalmethod.Theradialprofilesofthemagneticfield,electriccurrent,pressures,flowvelocitiesandtemperaturesbetweentheupanddown-streamradialforce-balancedplasmaoftheshockwererevealedbynumericalanalysis.Itisclearlyfoundthattheaxialshockcanleadtotwoeffects:oneisaninverseskineffect(i.e.,thecurrentdensityrisestowardsthecenteroftheconductor),theanotherisareversedcurrenteffectwhichoccursneartheedgeandaboutahalfradius.Itisalsofoundthattheradialgradientofpressure,densityandtemperatureallbecomeverylargenearthecenterduetotheaxialshock.

  • 标签: 等离子体物理 轴向震动 逆流 反向趋肤效应
  • 简介:Energydepositionofintensepulsedionbeam(IPIB)ontheTitargetbasedonthe2DmodelofIPIBdensityhasbeensimulatedbytheMonteCarlo(MC)method.Takingthedepositedenergyasthethermalsource,wehaveestablishedtheablationmodelofthetargetandcalculatedthespatialandtemporalevolutionoftheablationshapeoftheTitargetirradiatedbyIPIBwithdifferentenergydensities.WehavealsoestablishedtheejectionmodelofthehydrodynamicequationsrelatedtotheablationshapeofthetargetbyusingtheablationresultsastheinitialconditionsofplasmaformedbyIPIBirradiation.Thespatiallyandtemporallyevolutedprofilesoftheplasmapressureandmassdensityarecalculated.

  • 标签: 强脉冲离子束 数值计算 等离子体 蒙特卡洛法
  • 简介:Theapplicationofinductionplasmatechnologydevelopedforthesynthesisofnanometricpowdersissummarized.Abriefdescriptionofthescientificbasisfortheinductionplasmaprocessesisgiven,followedbythepresentationofaninductionplasmasystemdevelopedbyTekna,togetherwithvariousexamplesofthenanopowderssynthesizedusingitsfacilities.Theadvantagesoftheinductionplasmaprocessoveralternativetechniquesanditsadaptabilityintoindustrialscaleoperationisparticularlyillustrated.Somespecificissuesrelatedtothenanopowdersynthesisprocessarealsodiscussed.

  • 标签: 等离子体过程 综合开发利用 纳米粉体 感应 等离子技术 粉体合成
  • 简介:AnexperimentalsystemofACarcdischargeinwaterwasdesignedwithpole-poleelectrodesandapeakvoltageof1500Vandatestcircuitwassetupusingvirtualinstrumenttechnology.ThemechanismofanACplasmaarcgeneratedinwaterwasanalyzed.ThevoltagecurrentcharacteristicoftheACplasmaarcwasobtainedfromthewaveform.Thetemperaturecharacteristicwastestedwithaspectrumdiagnosissystem,andtheeffectofdifferentelectrodematerialsonthestrikingvoltageandpeakcurrentwasanalyzed.Theresultsshowthatwhenapowersupplyof6kWisappliedonelectrodeswithagapof2mminwater,thestrikingvoltageisfrom900Vto1300V,thearcvoltageisfrom40Vto100V,thearccurrentisfrom2Ato7A,andthezerorestperiodisfrom1msto2ms.Inaddition,thearcvoltageandcurrentaredifferentforelectrodesinaluminum,copperandstainlesssteel.Thearcvoltageislowerandthecurrentishigherforanaluminumelectrodethanthoseforcopperandstainlesssteelones.Thehighesttemperatureofthearcis7643K.

  • 标签: 交流等离子体 等离子体特性 电压电流特性 电极材料 峰值电压
  • 简介:SupersonicMolecularBeamInjection(SMBI)isanewfuellingmethodforTokamaksandhasrecentlybeenimprovedtoenhancethefluxofthebeamandtomakeasurveyoftheclustereffectwithinthebeam.Thereareaseriesofnewphenmnena,whichimplicatetheinteractionofthebeam(includingclusters)withthetoroidalplasmaofHiL-1MTokamak.TheHαsignalsfromtheedgeshowaregularvariationaroundthetorus.Aroundtheinjectionport,theedgeHαsignalsarepositiverectangularwave,whichisconsistentwiththatoftheinjectionbeampulses.Theedgeelectrontemperature,measuredwithmovableLangmuirprobes,decreasesbyanorderofmagnitudeandthedensityincreasesbyanorderofmagnitude.Hαemissionatthebeaminjectionport,measuredwithCCDcameraatanangleof13.4degreestotheSMBIline,showsmanyseparatepeakswithinthecontourplot.Thesepeaksmayshowthestrongemissionproducedbytheinteractionofthehydrogenclusterswiththeplasma.Hydrogenclustersmaybeproducedinthebeamaccordingtotheempiricalscaling(Hagena)lawofclusteringonset,heredisthenozzlediameterinμm,P0thestaguationpressureinmbar,T0thesourcetenperatureinK,andkisaconstantrelatedtothegasspecies.IfΓ*>100,clusterswillbeformed.InpresentexperimentΓ*isabout127.

  • 标签:
  • 简介:Theplasmageneratedinthelow-altitudeatmosphereisofhighcollisionfrequencies.Inthispaper,thetransmissioncoefficientsofmillimeter(MM)wavesnormallyincidentupontheplasmawithhighcollisionfrequenciesarecalculatedandanalyzed.Theexperimentalresultsofreflectionandattenuationarepresentedfortheeight-millimeterwavespropagatingthroughtheplasma.BoththecalculatedexperimentalresultsindicatethattheMM-wavesconcernedareattenuatedsignificantlyandreflectedweakly,whenpropagatingthroughtheplasmaofhighcollisionfrequencies.

  • 标签: 等离子体 碰撞频率 毫米波 反射率 投射率
  • 简介:Modelingofcarbonmonoxide(CO)removalbyacoronaplasmawasconductedinthisstudy.ThepurificationefficiencyofCOwascalculatedtheoreticallyandthefactorsaffectingtheremovalofCOwereanalyzed.TheresultsshowedthatthemainremovalmechanismsofCOweredirectdissociationbygeneratedhigh-energyelectronsandindirectoxidationbygeneratedhydroxylradicals.ThepurificationefficiencyofCOwasdependentontheplasmaparameters,indoorairhumidityandinitialconcentrationofCO.Goodconsistencybetweenthetheoreticalcalculationandtheexperimentalresultswasobserved.

  • 标签: 等离子体参数 一氧化碳 建模 二氧化碳 净化效率 计算理论
  • 简介:Newmethodsforboththetreatmentofpulpwasteliquorcalledblackliquor(BL)andtherecoveryofchemicalsbyusingplasma,andtheconcentrationofBLwiththefreezingtechniqueweredeveloped.Thenewmethodsaimingatthepilotplantscalearedescribedandtheexperimentsinasmall-scaleresearchfacilityfordemonstrationandtestarepresented.Theenergyconsumptionfortreatingwasteliquidis1kg/kWh.Plasmaprocessingcanreducethecostsfortreatmentandeliminatepollution.

  • 标签: 等离子体处理 冷冻技术 废纸浆 治疗 废液处理 能源消耗
  • 简介:Ananalyticalstudyispresentedonthemodaldispersioncharacteristics,groupvelocity,andeffectivegroup,aswellasthephaseindexofaternaryonedimensionalplasmaphotoniccrystalforanobliquelyincidentelectromagneticwaveconsideringtheeffectofcollisionsinplasmalayers.Thedispersionrelationisderivedbyusingthetransfermatrixmethodandtheboundaryconditionsbasedonelectromagnetictheory.Thedispersioncurvesareplottedforboththenormalphotonicbandgapstructureandtheabsorptionphotonicbandgapstructure.Itisfoundthattheincreaseintheangleofincidenceshiftsthephotonicbandgaptowardhigherfrequencies.Also,thecutofffrequencyisindependentofcollisions.

  • 标签: 倾斜入射 等离子体 电磁波 碰撞 晶体性能 一维
  • 简介:Inthepaper,relativisticfilamentationofintenselaserbeamininhomogeneousplasmaisinvestigatedbasedonthenonparaxialregiontheory.Theresultsshowthat,relativisticnonlinearityplaysamainroleinbeamfilamentation,andplasmainhomogeneityfurtherreinforcesthebeamfilamentation.Thecombinationeffectsofrelativisticnonlinearityandplasmainhomogeneitycangenerateparticularlyintenseandshortpulselaser.However,plasmainhomogeneityleadstoobviousfilamentationinstability.

  • 标签: 非均匀等离子体 强激光束 相对论 成丝 不均匀性 短脉冲激光