简介：

简介：用单辊甩带法制备了不含高生物毒性元素的Ti60Zr10Ta15Si15非晶薄带,并在高于其晶化开始温度的不同温度下对该非晶薄带进行了真空退火,研究了该非晶薄带在磷酸盐缓冲溶液（PBS）中的电化学腐蚀行为及热处理对其显微组织及其电化学行为的影响。结果表明,用单辊甩带法制备的Ti60Zr10Ta15Si15金属薄带为完全的非晶态结构,其玻璃转变温度和晶化开始温度分别为759K和833K,经过878K真空热处理后,薄带发生了部分晶化,在非晶的基底上析出了Ti相;经过938K热处理后,薄带发生了完全晶化,晶化相主要由Ti、Si3Ta5和SiZr以及TiSi组成。动电位极化测试表明,该非晶合金在PBS溶液中可表现出较为优异的耐蚀性能,部分晶化可进一步提高该合金的耐蚀性能,而完全晶化的合金抗腐蚀性能明显下降。

简介：Asanimportantmulti-functionalmaterialappliedinsurfaceacousticwavedevices,opticalcommunications,laserandoptoelectronicsduetoitsgoodphotoelectricandpiezoelectricproperties,lithiumtantalate(LiTaO3)hasdrawnextensiveinterests[1].NumerousphysicalpropertiesofLiTaO3,suchasacoustical,electronicstructures,opticalpropertiesandeffectivemass,thermodynamicproperties,havebeenreportedinseveralpapers.Pointdefectswillaffecttheelectronicstructurewhichshouldberesponsibleformanyphysicalproperties,especiallyopticalproperties.

简介：Fieldemissionoccurredinsuperconductingradio-frequency(SRF)cavitiesisthemajorobstacleoftheacceleratorsoperatingathighgradient,whichpartlycausedbytheinnersurfacecontamination,suchasthehydrocarbonsandtheabsorbedresidualgas.Theplasmaprocessingcanbeaneffectivemethodtosolvethefieldemissionissues.Thepropertiesoflowtemperatureglowdischarge,whichwasargonplasmawiththechemicallyreactiveoxygen,wereinvestigatedfortheSRFcavitiesusedforCADSproject.

简介：

简介：ThispaperstudiestheequilibriumgeometriesandelectronicpropertiesofBenandBenLiclusters,upton=15,byusingdensity-functionaltheory(DFT)atB3LYP/6-31G(d)level.Thelowest-energystructuresofBenandBenLiclustersweredetermined.Theresultsindicatethatasinglelithiumimpurityenhancesthestabilityandchemicalreactivityoftheberylliumclusters.Itfindsthatthegeometriesofthehostclusterschangesignificantlyaftertheadditionofthelithiumatomforn≥8.Thelithiumimpuritypreferstobeontheperipheryofberylliumclusters,andoccupiesvertexsites.BothBe4Li,Be9Li,andBe13Liwerefoundtobeparticularlystablewithhigheraveragebindingenergy,localpeaksofsecond-orderenergydifferenceandfragmentationenergies.ForalltheBenLiclustersstudied,wefoundchargetransfersfromtheLitoBesiteandco-existenceofcovalentandmetallicbondingcharacteristics.更多还原

简介：Ithasbeenproposedthatfusionreactionsbetweenneutron-richlightnuclei,forexample24C,24Oand28Ne,maycontributetoachievingtheignitiontemperatureforexplosivecarbonburningprocessduringsuperbusrsts[1,2].Studiesoffusionreactionsinvolvingneutron-richnucleiarebeyondordinaryexperimentaltechniques,sincetheintensityofradioactivebeambecomelowforthesemeasurements[3].TheactivetargettechniqueusingTPC(TimeProjectionChamber),withpropertiesofmulti-sampling,highefficiencyandlowbackground,isasuitablesolutiontotheproblem.

简介：

简介：

简介：Themesonproductioninnucleon-nucleoncollisionsnearthresholdhasthepotentialtogaininformationonhadronpropertiesandalsoplaysanimportantroleinexploringthebaryonspectroscopy[1].Inrecentyears,theexperimentaldatabaseonthereactionofpp!ppK+Knearthresholdhasbeenexpandedsignificantly.Inadditiontothemeasurementsofthetotalanddifferentialcrosssections,belowthethresholdoftheproductionofthe?meson,performedexperimentallywithCOSY-11andANKEdetectorsatthecoolersynchrotronCOSYinGermany,invariantmassdistributionsofvarioussubsystemshavebeenobtainedatlowenergies.Unlikeabovethethresholdoftheproductionofthe?meson,inthelowenergyregion,wedonotneedtoseparatethenon-?fromthe?contribution,andduetothefactthatthedatawerespreadoverawiderangeofK+K??invariantmasses,ithasaspecialadvantagetoinvestigatethescalarmesonsa0(980)$andf0(980)whicharedynamicallygeneratedfromtheinteractionsofK￣K,ππ,andπηtreatedascoupledchannelsinI=0andI=1,respectively.BothofthemcouplestronglytotheK￣Kchannel.

简介：采用环境氢脆技术及现代材料微观分析技术，研究了Fe-35Ni-15Cr实验合金在室温至900℃的力学性能及热充氢后在室温及750℃的力学性能，分析了温度对材料微观组织的影响，为优化其化学成分、热处理工艺等提供技术依据。