简介：Inordertostudytheeffectoftheparameterssuchastheenergydensityandthegasvelocityonthetransportrateofions,theappliedforceandthemotionlawofchargedparticlesintheelectricfieldofcoronadischargesatatmosphericpressureisinvestigatedinthispaper.Asaresult,whenthegasvelocityisraisedfrom1.5m/sto25m/sforanenergydensityof0.4mJ/cm~3,theionictransportrateincreasesfrom5.4×10~8/cm~3.sto8×10~(10)/cm~3.s,whichisanincreaseofovertwoordersofmagnitude.However,inthe-zonesof-streamerandglowdischarges,theeffectoftheinputehergydensityandtheenergydensityofgasionizationonthetransportrateisbelowoneorderofmagnitude.Inconclusion,theincreaseofchargedparticlemomentumcanbeamajorfactorinraisingthetransportrateandreducingthevolumeoftheplasmasources.

简介：ThesolutionofGrad-Shafranovequationdeterminesthestationarybehavioroffusionplasmainsideatokamak.Tosolvetheequationitisnecessarytoknowthetoroidalcurrentdensityprofile.Recentworksshowthatitispossibletodetermineamagnetohydrodynamic(MHD)equilibriumwithreversedcurrentdensity(RCD)profilesthatpresentsmagneticislands.InthisworkweshowanalyticalMHDequilibriumwithaRCDprofileandanalyzethestructureofthevacuumvectorpotentialassociatedwiththeseequilibriausingthevirtualcasingprinciple.

简介：TheprecisionofplasmaelectrondensityandFaradayrotationanglemeasurementisakeyindicatorforfar-infraredlaserinterferometer/polarimeterplasmadiagnosis.Toimprovetheprecision,anewmulti-channelhighsignal-to-noiseratioHCOOHinterferometer/polarimeterhasbeendevelopedontheHL-2Atokamak.Ithasahigherlevelrequirementforphasedemodulationprecision.Thispaperintroducesanimprovedreal-timefastFouriertransformalgorithmbasedonthefieldprogrammablegatearray,whichsignificantlyimprovestheprecision.Wealsoapplyareal-timeerrormonitoringmodule(REMM)andastableerrorinhibitingmodule(SEIM)forprecisioncontroltodealwiththeweaksignal.Wetesttheinterferometer/polarimetersystemwiththisimprovedprecisioncontrolmethodinplasmadischargeexperimentsandsimulationexperiments.Theexperimentalresultsconfirmthattheplasmaelectrondensityprecisionisbetterthan1/3600fringeandtheFaradayrotationanglemeasurementprecisionisbetterthan1/900fringe,whilethetemporalresolutionis80ns.ThisperformancecanfullymeettherequirementsofHL-2A.

简介：Thisworkinvestigatesinternalplasmaprocessparametersusingahairpinresonanceprobeandopticalemissionspectroscopy.ThedependenceofelectrondensityandatomicfluorineonthepercentageofoxygeninanSF6/O2dischargewasmeasuredusingthesemethods.AnRIEOxfordInstruments80pluschamberwasusedfortheexperiments.Twodifferentprocesspowers(100Wand300W)ataconstantpressure(100mTorr)wereused,anditwasfoundthattheopticalemissionintensityofthe703.7nmand685.6nmlinesofatomicfluorineincreasedrapidlyasoxygenwasaddedtotheSF6discharge,reachedtheirmaximumatanO2fractionof20%andthendecreasedwithfurtheradditionofoxygen.TheplasmaelectrondensitywasalsostronglyinfluencedbytheadditionofO2.

简介：TimeevolutionofionosphericD-regionplasmasincludingtheperturbationsofelectronsandchargedaerosolparticlesisinvestigatedundertheconditionsofpolarmesospheresummerechoes(PMSE).ItisshownthatthetimescaleofdecayoftheelectrondensityisintheorderofanhourundertypicalPMSEconditions,inthemajorityofcases,theelectrondensityisanticorrelatedtotheiondensity,exceptthattheradiusofaerosolparticlesisgreaterthan50nm.Also,theevolutionsundervariedparameters,suchastheamplitudeandwidthofperturbation,theaerosolparticleradius,andthealtitudeofthePMSEoccurrenceareinvestigated.Theobtainedresultsareusefulforinterpretingtheexperimentalobservations.