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简介：ThemetalbindingsitesinthetwoPtcontainingmetallothioneins(Pt-MTandPt14MT)wereexaminedbymeansofPt(II)L3-edgeextendedX-rayabsorptionrinestructure(EXAFS)spectroscopy.ComparisonsbetweenthephaseandamplitudefunctionsderivedfromtheisolatedshellstothoseofPt…Pt.Pt-SandPt-NmodelcomponentsshowedthateachplatinuminPt7MTwascoordinatedbyfoursulfuratomsatadistanceof2.31±0.01A.AnalysisoftheoutershelldataofplatinumatominPt7MTindicatedbackscatteringplatinumatomatapproximate4.29A.StrkinglydifferentstructuralparametershadbeenobtainedforthePt14MTspecies.fittingofthefirstshellrevealedthateachplatinumwascoordinatedbytwosulfursatthedistanceof2.3-±0.02Aandtwonitrogensat2.02±0.02A.TheresultsoftheworkprovidedthedetailedinformationconcerningthelocalenvironmentsofthecoordinatedPt(II)inthesetwoplatinothioneins.

简介：TheatomicstructureofanovelrareearthcomplexconsistingofNdandthesulfur-containingligandpipdtc(C5H10NCS2^-)hasbeenstudiedwithextendedx-rayabsortpitonfinestructure(EXAFS)andx-raydiffractiontechniques.ThecomplexofformulaNd(pipdtc)4N(CH3)4crystallizaesinthemonoclinicspacegroupP21/nwiththefollowinglatticeparameters,a=22.685(2),b=20.332(2),c=17.1270(10)A,β=100.570(10)°.Z=8,thecalculateddensityis1.47g/cm^3,Anewderivativemethodisusedtoremovethepiost-edgeabsorptionbackgroundincludingthemultielectronexcitationeffect.TheEXAFSresultsdemonstratethatthereareabouteightSandfourOatomsaroundNdwiththeNd-Sbondlengthof2.916AandtheNd-Obondlengthof2.415A,respectively.Thisimpliesthatthepowderofthiscomplexisnotstableandiseasytooxidizeinair.Thepossiblechangeofstructurebeforeandafteroxidationisdiscussed.

简介：Thepedestalcharacteristicisanimportantbasisforhighconfinementmode(Hmode)research.BecauseofthefinitespatialresolutionofThomsonscattering(TS)diagnosticonExperimentalAdvancedSuperconductingTokamak(EAST),itisnecessarytocharacterizethepedestalwithasuitablefunctionalform.BasedonsimulatedandexperimentaldataofEAST,itisshownthatthetwo-linemethodwithabilinearfittinghasbetterreproducibilityofpedestalparametersthanhyperbolictangent(tanh)andmodifiedhyperbolictangent(mtanh)methods.ThismethodhasbeenappliedtoEASTtypeIedgelocalizedmode(ELM)discharges,andtheelectronpedestaldensityisfoundtobeproportionaltotheline-averageddensityandtheedgepressuregradientisfoundtobeproportionaltothepedestalpressure.Furthermore,theionpoloidalgyro-radiushasbeenidentifiedasthesuitableparametertodescribethepedestalpressurewidth.

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简介：Organicgermaniumcompoundshavebeenextensivelyappliedinmedicineastonics,Inthispaper,thelocalstructuresoftwoorganicgermaniumcompounds,carboxyethylgermaniumsesquioxideandpolymericgermaniumglutamate,weredeterminedbyEXAFS.Thestructureparametersincludingcoordinationnumbersandbondlengthswerereported,andpossiblestructurepatternswerediscussed.

简介：Photoconductivityspectrameasurementofpolymersatx-rayenergiesaroundtheZnandCoKedges,showsobviousx-rayabsorptionfinestructureoscillations.Thephotoconductivityspectraobtainedforgappedandsandwichedelectrodegeometricsamples,indicatethattheshapeofphotoconductivityspectrumdependsontheelectrodeconfigurationofthesamples.Thethicknessoftheconductionlayercanbeestimatedfromthephotoconductivityspectrum.

简介：Micro-/nanocrystallinediamondfilmsdepositedinAr/H2/CE4microwaveplasmashavebeenstudied,withargonflowratesintherangeof70-100seem.Theeffectsofargonadditiononmorphology,surfaceroughness,qualityandstructurewereinvestigatedbyscanningelectronmicroscopy,surfaceprofiler,RamanspectrometerandX-raydiffraction（XRD）.Itisdemonstratedthatwhentheargonflowrateis70sccmor75sccm,well-facetedpolycrystallinediamondfilmscanbegrownatalowsubstratetemperaturelessthan610℃.Withtheincreaseintheargonflowrate,thesmoothcrystallographicplanesdisappeargradually.Instead,roughcrystallographicplanesmadeupofsmallaggregatesbegintotakeshape,resultingfromtheincreaseinthesecondarynucleationrate.Nanocrystallinediamondfilmswereobtainedataflowrateof100sccm,andalloftheprepareddiamondfilmsweresmooth,withasurfaceroughness（Ra）lessthan20nm.Ramananalysesrevealthattheamountofamorphouscarbonincreasessignificantlywiththeincreaseinargonflow.TheresultsofXRDshowthatcrystallinesizeandpreferentialorientationofdiamondfilmsdependontheargoncontentintheplasmas.

简介：Consideringutilizationoftheoriginalchromium-bronzematerial,twoprocessingtechniquesincludinghydraulicexpansionandhightemperaturevacuumweldingwereproposedfortheoptimizationofheat-sinkstructureinEAST.Theheattransferperformanceofheat-sinkwithorwithoutcoolingtubewascalculatedanddifferenttypesofconnectionbetweentubeandheat-sinkwerecomparedbyconductingaspecialtest.Itisshownfromnumericalanalysisthatthediameterofheat-sinkchannelcanbereducedfrom12mmto10mm.Comparedwiththeoriginalsample,thethermalcontactresistancebetweentubeandheat-sinkforweldingsamplecanreducetheheattransferperformanceby10%,whileby20%forthehydraulicexpansionsample.However,theweldingtechniqueismorecomplicatedandexpensivethanhydraulicexpansiontechnique.Boththeprocessingtechniqueandtheheattransferperformanceofheat-sinkprototypeshouldbefurtherconsideredfortheoptimizationofheat-sinkstructureinEAST.

简介：Thedielectricbarrierdischarge(DBD)intheglowregimeinneonhasbeeninvestigatedbyexperimentandtwo-dimensional(2D)fluidmodeling.ThedischargewascarriedoutinaplanarDBDsystemwithsegmented-electrodesdrivenbysquare-wavevoltage.TheresultsshowthattheglowDBDoriginatesinthecenteroftheelectrodeandexpandsoutwardtotheelectrodeedgeduringeachhalfcycleofthevoltage,formingaradialstructure.Thedischargedecaysfirstlyintheinnerareabutsustainslongerintheedgearea,showingareverseddischargearea.Thedischargecannotcompletelycovertheentireelectrodesurface,butremainsaborderofnon-orweakdischarge.Thefluidmodelingshowsasimilarresultinagreementwiththeexperiments.Thesimulationsindicatethattheelectricfieldintheedgeareaisdistortedduetotheboundaryeffectsothattheelectricfieldandchargedistributionaredifferentfromthatintheinnerpart.Thedistortedfieldreducesthelongitudinalcomponentneartheedgeandcausesthelocalfieldtobelowerthanthatinthecenter,andhencemakesthedischargebehindhand.Italsoinducesatransversefieldthatmakesthedischargeextendradiallyoutwardtotheedge.TheboundaryeffectplaysanimportantroleintheglowDBDstructure.

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简介：Theinfluenceofthehystereticbehaviourinreactivesputteringwithapurealuminiumtargetinthepresenceofargonandoxygenplasmaontransmittanceandsurfacefreeenergyofaluminiumoxidefilmswasinvestigatedbyplasmaopticalemissionspectroscopytechnology.Theevolutionsofaluminium,andaluminiumoxideemissionlinesasfunctionsofoxygenflowrateatconstantpowerandpressurewerestudied.Asteeptransitionfromthemetallicsputteringtothecompoundsputteringwasobserveduponincreasingtheoxygenflowratefrom0.0SCCMtoabove2.0SCCM.Thenanoptimaldepositionzonewasobtainedthroughanalyzingthehystereticcurvesofaluminiumandaluminiumoxideemissionlines.TheevolutionofcrystalstructuresofsampleswasdiscernedbyX-raydiffractionspectradata.EnergydispersiveX-rayspectroscopydataalsodemonstratetherelationshipbetweenthechemicalcompositionsofaluminiumoxidefilmsandthehystereticbehaviour.Thefilmdepositedbetween1.5SCCMand2.0SCCMoxygenflowratedisplaysanoptimalandstoichiometicatomicratioofOtoAlandmassratioofOtoAl.ThechangesinthetransmittanceofsampleswerediscoveredtodependontheoxygenflowratebyUV-VIStransmittancespectra,andthechangesinsurfacefreeenergywerestudiedbycontactanglemeasurement.

简介：Theplasma-neutralgasstructuregeneratedinamagnesiumcathodicarcoperatedwithoxygengasataconstantcurrentof50Ahasbeeninvestigatedbyemployingasimplifiedone-dimensionalfluidmodel.Themodelincludeselasticcollisionsandcharge-exchangereactionsbetweenmetallicparticlesandgasmolecules,andalsogenerationandrecombinationofgaseousionsbyelectronimpact.Thedistributionprofilesofdensityandvelocityofspeciesalongtheaxialdirectionwereobtainedatdiferentbackgroundgaspressures(intherangeof0.7~3.0Pa)bythismodel.Acomparisonwiththeexperimentswasmade.Atlowergaspressures,thedepositingparticlesweremainlythemetallicionswithalargerkineticenergy.Asthegaspressureincreased,themagnesiumatomswithsmallerkineticenergyactedasthedominantdepositingspecies.Determinedbytheminimizationofthesystem’stotalenergy,MgO(100)or/andMgO(110)orientationappearedeasilyintheMgOfilmsatlowergaspressures,andathighergaspressures,thefilmpreferredorientationwasMgO(111).

简介：Theγ-Fe2O3nanoparticlescoatedwithDBSandCTABwerepreparedbythemicroemulsionmethod.Thecoatedsamplesshowenhancednonlinearopticalpropertiescomparedwiththeirbulkcouterpart.The.Moessbauerspectraatroomtemperatureweremeasuredforthecoatedferricoxides.Themonolayersoftheorganicmoleculearefoundtohaveastrongchemicalbondwiththesurfaceatomsandthushaveasignificantinfluenceontheelectronstructureofparticlesurface.@1999ActaMetallurgicaInc.

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：AseriesofoxideizedCO-K-Mo/γ-Al2O3catalystsamples,preparedbyimpregnatingoxidizedK-Mo/γ-Al2O3sampleswithanaqueoussolutionofcalculatedCo(NO3)2andthencalcininginairattemperaturesof350℃，500℃65℃and800℃respectively,weresulfidedandtheninvestigatedfortheactivityinthesynthesisofmixedalcoholsfromCOhydrogenationunderconditionsofp=5.0MPa,T=350℃andGHSV=4800h^-1.TheresultsdemonstratethattheadditionofcobaltpromoterisfavorabletotheformationofhigheralcoholsandtheopimumcalcinationtemperaturesafterimpregnatingwithCo^2+areabout500-650℃.ThestructureofCoandMospeciesontheoxidizedandsulfidedsampleswasdeterminedbyX-raydiffraction(XRD),laserRamanspectrum(LRS)andextendedX-rayabsorptionfinestructure(EXAFS).Foroxidizedsamplecalcinedat350℃,cobaltexistsasCo3O4spectiesandcoversthesurfaceofK-Mo-Ospecies,thestructureofK-Mo-OspeciesisthesameasthatinK-Mo/Al2O3sample.TheinteractionbetweencobaltandK-Mo-Ospeciesisrelativelyweak.Aftersulfidation.Cobaltexistsassulfidecrystalliteswithanoctahedralcoordinatedstructure,andmolybdenumasMoS2crystallites.Foroxidizedsamplescalcinedat500-650℃,CocomponentinteractswiththeK-Mo-Ospeciesanddestroysthelong-rangeorderoftheK-Mo-Ospectesgradually,Aftersulfidation.CotendstoexistasasulfidewithtetrahedralcoordinatedstructureandMostillasMoS2crystallites.Foroxidizedsamplecalcinedat800℃,CocomponentexistsmainlyasCoAl2O4species,mostofwhichcannotbesultidedduringsulfidation.

简介：InthedischargeofEASTtokamak,itisobservedthat（2,1）neoclassicaltearingmode（NTM）istriggeredbymodecouplingwitha（1,1）internalmode.Usingsingularvaluedecomposition（SVD）methodforsoftX-rayemissionandforelectroncyclotronemission（ECE）,thecouplingspatialstructuresandcouplingprocessbetweenthesetwomodesareanalyzedindetail.TheresultsofSVDforECErevealthatthephasedifferencebetweenthesetwomodesequalstozero.Thisisconsistentwiththeperfectcouplingcondition.Finally,performingstatisticalanalysisofγ1/1,ζ1/1andω2/1,wefindthatγ1/1moreaccuratelyrepresentsthecouplingstrengththanζ1/1,andγ1/1isalsostronglyrelatedtothe（2,1）NTMtriggering,whereγ1/1isthewidthof（1,1）internalmode,ζ1/1istheperturbedamplitudeof（1,1）internalmode,andω2/1denotesthemagneticislandwidthof（2,1）NTM.

简介：WereportonastudyofinterfacialstructureofGaNfilmsgrownonGaAs(001)substratesbyplasma-assistedmolecularbeamepitaxyusingx-raygrazing-anglespecularreflection.WeshowthatinterfaciallayerswithelectrondensitiesdifferingfromthoseofGaNandGaAswereformedupondepositionofGaN.Itisalsofoundthattheinterfacialstructureofoursystemsdependsstronglyonthecourseoftheinitiallayerdeposition.ThephasepurityoftheGaNfilmswasexaminedbyx-rayreciprocalspacemapping.Asimplekineticgrowthmodelsuggestedbyourresultshasbeenpresented.

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.