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894 个结果
  • 简介:PlasmaScienceandTechnology(ISSN1009-0630,CN34-1187/TL),anEnglishjournaloftheInstituteofPlasmaPhysics,theChineseAcademyofSciences(ASIPP)andtheChineseSocietyofTheoreticalandAppliedMeohanics,acceptspapersaboutnewachievementsandphaseresultsofplasmaphysics.Specificinterestareas

  • 标签: 等离子体工程科学 投稿说明 摘要 中文姓名 联系方式
  • 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: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:Anexperimentandanalysisonremovalofgaseousbenzenebypulsecoronainducedplasmaispresentedinthisarticle.Importantparameterseffectingremovalefficiencyhavebeeninvestigated,suchaspulsepeakvoltage,pulsefrequency,gasinletconcentration,gasflowrateandreactortemperature.Theresultshowsthattheremovalefficiencyincreaseswiththeincreaseinpulsepeakvoltage,pulsefrequencyandreactortemperature,butdecreasesintheriseofgasinletconcentrationandgasflowrate.OntheconditionofVp=36kV,f=80Hz,C=1440mg/m^3andQ=640ml/min,thelargestremovalefficiencyis98%.Finally,thereactedproductsarequalitativelyanalysedandthereactionprocessesarededucedincombinationwithplasma-chemistrytheory.

  • 标签: 射流等离子体 气态苯处理 挥发性化合物 等离子体反应器
  • 简介:Inthiswork,resultsonthestudyofthestructureandphotoluminescence(PL)propertiesofSiOxNythinfilmsarepresented.Thefilmsweredepositedatroomtemperatureusingadual-ion-beamco-sputteringsystem.TheXRDandTEMresultsshowthatthedepositedfilmshaveanamorphousstructure.IntheXPSresult,wefindN1sspectraconsistofonesymmetricsinglepeakat397.8eV,indicatingthatthenitrogenatomsaremainlybondedtosilicon.ItisinagreementtotheresultofFTIR.InSiOxNyfilms,anintensesinglePLpeakat590nmisobserved.Furthermore,withtheincreaseoftheNcontentintheSiOxNyfilms,theintensityofthePLpeakat590nmincreasesalot.ThePLpeakof590nmissuggestedtooriginatefromN-relateddefects.

  • 标签: 光致发光 氮氧化硅薄膜 双离子束沉积 薄膜结构
  • 简介:Anewtwo-dimensionalstructuremodulationalongc-andb-axeshasbeendiscoveredinsuperconductingsinglecrystalsofBi2.13Sr1.87CuO6+δ(Bi2201)byx-rayscattering.Suchmodulationstructuredoesnotexistinnon-superconductingBi2201singlecrystals.Butinsteadlatticedistortionsareobservedinthea-b-plane.Thisphenomenonmayindicatethatbothstrainrelaxationandchargemodulationinthea-b-planeareimportanttotheoccurrenceofsuperconductivityinthecopperoxides.

  • 标签: 超导体 调制结构 实验观测
  • 简介:Geepilayersofdifferentthicknessesaregrownbymolecular-beamepitaxywithSbasasurfactantonSI(100)substrates,X-raydiffractionillustratesthattheseGethinfilmsarepartiallystrained.andthestrainsdecreasegraduallywithincreasingepilayerthickness,RamanspectrarevealadownwardshiftoftheGe-Gemodepeakastheepilayerthicknessincreases.Intheregionsofhighstrain,therelationshipbetweentheRamanshiftofthismodeandthestraininthepartiallyrelaxedsamplesisconsiderablydifferentfromthelinearrelationshipreportedbefore,whichismainlyattributedtothespatialconfinementeffectofphononsinananocrystal.

  • 标签: 镓外延薄膜 硅衬底 形变研究
  • 简介:WereportonastudyofinterfacialstructureofGaNfilmsgrownonGaAs(001)substratesbyplasma-assistedmolecularbeamepitaxyusingx-raygrazing-anglespecularreflection.WeshowthatinterfaciallayerswithelectrondensitiesdifferingfromthoseofGaNandGaAswereformedupondepositionofGaN.Itisalsofoundthattheinterfacialstructureofoursystemsdependsstronglyonthecourseoftheinitiallayerdeposition.ThephasepurityoftheGaNfilmswasexaminedbyx-rayreciprocalspacemapping.Asimplekineticgrowthmodelsuggestedbyourresultshasbeenpresented.

  • 标签: GAN薄膜 分子束外延生长 X射线衍射 实验研究
  • 简介:TheexperimentalapparatusofX-rayfluorescence(XRF)microprobeanalysisatBeijingSynchrotronRadiationFacility(BSRF)isdescribedUsingthebovineliverasthestandardreference.theminimumdetectionlimit(MDL)oftraceelementwasmeasuredtodeterminethecapabilityofbiologicalsampleanalysisbysynchrotronradiationXRFmicroprobe.TherelativechangeofthecontentofthemajorortraceelementinthenormalandtumorpartofhumanbonetissueslicewasinvestigatedTheexperimentalresultrelationtotheclinicalmedicinewasalsodiscussed.

  • 标签: 人体胃癌 同步加速器辐照 X射线荧光分析
  • 简介:ThegrowthdetectsinNd:YCa4O(BO3)3(Nd:YCOB)crystalswereinvestigatedbytransmissionsynchrotrontopography.ItwasfoundthatgrowthstriationsweretheprimarydefectsinNd:YCOBcrystals.Grown-indislocations.mosaicblocksandinclusionswerealsoobseredinthecrystals.Theeffectoftemperaturefieldontheformationofgrowthdefectsinthecrystalswasdiscussed.

  • 标签: 晶体缺陷 Nd:YCa4O(BO3)3 辐照地形观测
  • 简介:Insituwhite-beamsynchrotronradiationtopographicobservationsunderanelectricfieldhavebeenmadeontheKTiOPO4(KTP)familyofcrystals.Theinvestigationshowsastrongenhancementofdiffractedintensityforhklreflections(l≠0)andtopographiccontrastintheformoffinestriationswhentheexternalelectricfieldisparalleltothepolaraxis.Severalkkindsofdopedandundopedsampleswithvariousgrown-indefects,suchasdomainboundaries.growthstriations,growth-sectorboundaries.dislocations.etc.,havebeenstudiedindetail.Theresultssuggestthatthesedefectshaveverylittleeffectonthefield-inducedstriations,ItisbelievedthatthemovementofK^+ionsdrivenbytheelectricfieldleadstoalocalaccumulationofchargesandalatticedistortion.Thestronlyanisotropicconductivityisagoverningfactorintheexplanationofthefield-relatedphenomenainthiskindofquasi-one-dimensionalconductor.

  • 标签: KTiOPO4晶体 辐照观测 电场
  • 简介:ThetransientopticalpropertiesofnovelPbSnanoparticlescoatedwith2.6-O-diallyl-β-cyclodextrines(CDs)werestudiedbythefemtosecondpump-probetechnique.Theresultsshowthattheultrafasttransient-inducedabsorptionforthenovelcase.ComparedtothePbSnanoparticlesstabilizedwithpolyvinylalcohol(PVA),wefindthattheprocessforthenovelcaseisdifferentfromthePbS(PVA),WesuggestthattheCDssurfacemodificationcantrapholesonthesurfaceofPbSnanoparticles.ThiscaninduceanefficientchargeseparationbetweenthePbSnanoparticlesanditssurfaceandresultinanultrsafast-inducedabsorptionfornovelPbSnanoparticles.

  • 标签: PBS 纳米颗粒 表面化学处理 非线性光学特性
  • 简介:TheballmillingofFe-24MnandFe-24Mn-6Simixedpowdershasbeenperformedbythehighenergyballmillingtechnique.ByemployingX-raydiffractionandMoessbauermeasurements.Theccmpositionevolutionduringthemillingprocesshasbeeninvestigated.TheresultsindicatetheformationofparamagneticFe-MnorFe-Mn-Sialloyswithametastablefccphaseasfinalproducts.whichimplythattheFeandMnproceedaco-diffusionmeenanismthroughthesurfaceoffragmentedpowders.Thethermalstabilityandcompositionevolutionoftheas-milledalloyswerediscussedcomparingwiththebulkalloy,.

  • 标签: 合金 FE-MN FE-MN-SI 穆斯鲍尔效应
  • 简介:Highsolid-solubilityCo15Cu35alloyshavebeenpreparedbymeltspinningandsubmittedtoisothermalandanisothermalannealingtoobtaingranularalloys.TheX-raydiffraction(XRD)patternsweremeasuredtoinvesugatethedecompositionofsupersaturatedsolidsolutioninducedbyannealing.Theatomicdiffusionandstructuralevolutionduringtheheattreatmentwereinvestigated.Inviewoftheproblemslimitingtheirappllcation.thehigh-fieldmagneazationcurvesweremeasured.Byafittothehigh-fieldmagnetizationcurves,thegranuiaralloysarefoundhardtobemagneticallysaturatedattheearlystageofnucleationandgrowth.Themagnetizationbehaviorwascorrelacedtotheannealed-inducedstructurealevolutionandalsotothemagnetoresistanceeffect.

  • 标签: Co-Cu合金 磁化过程 X射线衍射
  • 简介:Fe2O3nanoparticlescoatedwithsodiumdodecylbenzenesulphonate(DBS)orcetyltrimethylammoniumbromide(CTAB)werepreparedbyusingamicroemulsionmethodinthesystemwater/toluene.Thenanoparticleswerecharacterizedbymeansoftransmissionelectronmicroscopyandaverageparticlesizesof5.0nmand6.0nmwerefoundforDBS-modifiedandCTAB-modifiednanoparticlesrespectively.Thelocalatomicstructuresoftheseiron(Ⅲ)oxidenanoparticleswereprobedbyusingtheextendedx-rayabsorptionfine-structuretechnique.FeKabsorptionspectrawerecollectedatbeamline4W1BofBeijingSynchrotronRadiationFacility.Astructurealmodelwasproposedfordescribingtheiratomicstructures.TheFe-ObondlengthatthesurfaceofDBS-coatedFe2O3nanoparticleswasfoundtobesimilartothatinbulkFe2O3.buttherewasabout0.04AexpansionfortheCTAB-coatedFe2O3nanoparticles.Onthebasisofthemodelproposedinthispaper,thethicknessesofthesurfacelayerswereestimatedtobe0.5nmand0.7nm.respectively,fortheDBS-coatedandCTAB-coatedFe2O3nanoparticles.Theanharmonicityoftheatomicvibrationandtheasymmetryofatom-pairdistributionwerefoundtobelargeratthesurfaceofthenanoparticlesthaninthebulkmaterial,whiletheDebye-Wallerfactorsarealmostthesameforthesurfaceandthecorepartsofthenanoparticles.Itcanbeconcludedthattheatomicstructureofthenanoparticlesurfaceisordered.buttheatom-paridistributionisasymmetric.

  • 标签: 氧化铁 纳米粒子 表面原子结构
  • 简介:Organicgermaniumcompoundshavebeenextensivelyappliedinmedicineastonics,Inthispaper,thelocalstructuresoftwoorganicgermaniumcompounds,carboxyethylgermaniumsesquioxideandpolymericgermaniumglutamate,weredeterminedbyEXAFS.Thestructureparametersincludingcoordinationnumbersandbondlengthswerereported,andpossiblestructurepatternswerediscussed.

  • 标签: 锗原子结构 锗有机化合物 EXAFS
  • 简介:LocalstructuresofthemolybdenumsulfidespeciesinthesultidedRh-Mo-K/Al2O3catalystswithvariousrhodiumloadingshavebeeninvestigatedbyXAFS.Fromthefittingresults.theMo-Mocoordinationnumberforthesamplefreeofrhodium(ca.3.7)issimilartothatforthecrystallineMoS2,indicatingthatthesupportedsulfidedmolybdenumspeciesmainlypresentaslargepatechesofMoS2-likeslabs.Fortherhodium-modifiedsamples,however,theamplitudesoftheMo-SandMo-Mocoordinationshellsaresharplyreduced,revealingahighdispersionoftheMoS2-likespeciesinthecatalysts,TheschemeofthemicrostructuresofthesulfidedmolybdenumspeciesstabilizedonthealuminasupportisdiscussedbasedupontheanalysisoftheEXAFSdata.

  • 标签: 硫化Rh-Mo-K/Al2O3 催化剂
  • 简介:Photoconductivityspectrameasurementofpolymersatx-rayenergiesaroundtheZnandCoKedges,showsobviousx-rayabsorptionfinestructureoscillations.Thephotoconductivityspectraobtainedforgappedandsandwichedelectrodegeometricsamples,indicatethattheshapeofphotoconductivityspectrumdependsontheelectrodeconfigurationofthesamples.Thethicknessoftheconductionlayercanbeestimatedfromthephotoconductivityspectrum.

  • 标签: 聚合物 光导测量 X射线吸收 精细结构
  • 简介:Extendedx-ray-absorptionfine-structuremeasurements(EXAFS)wereperformedonnanocrystalline(nc)elementalSesampleswithgrainsizesrangingfrom13to60nm.Accompaniedwiththepreviousstudy,weconcludedthat,withtherefinementinnc.Se.theintrachainstructure(thebondlength,thecoordinationnumber)isunchangedwhiletheinterchainspacingisenlarged.ThegrainboundaryinthencSeisfoundtobeinalow-energyconfigurationthatisdifferentfromthedisorderedgaslikegrainboundarystructure.

  • 标签: 纳米结晶 结构特征 晶粒尺寸
  • 简介:Thenanoparticlesγ-Fe2O3coatedwithsurfactants.DBS,STandCTAB.repsectively.weresynthesizedbymicroemulsionmethod.Thecoatedferricoxides.whichshowenhancednonlinearopticalpropertiescomparedwiththeirbulkcounterpart.wereprobedbyEXAFSinsolutionforms.Thex=-rayabsorptionspectraforFeKedgeweremeasuredatroomtemperaturebyhelpofsynchrotronradiationlightsource.Extendedx-rayabsorptionfinestructureanalysisshowsthatthecoatinglayersoforganicmoleculesinteractwithsurfaceatomsofnanopartices,theFe-Obondlengthwasextended.

  • 标签: 氧化铁 纳米粒子 涂层 有机活化剂 EXAFS