简介:ThesplittingofpotentialenergylevelsforgroundstateX2ΠgofOx2(x=+1,1)underspin–orbitcoupling(SOC)hasbeencalculatedbyusingthespin–orbit(SO)multi-configurationquasi-degenerateperturbationtheory(SO-MCQDPT).TheirMurrell–Sorbie(M–S)potentialfunctionsaregained,andthenthespectroscopicconstantsforelectronicstates2Π1/2and2Π3/2arederivedfromtheM–Sfunction.TheverticalexcitationenergiesforOx2(x=+1,1)areν[O+12(2Π3/2→X2Π1/2)]=195.652cm1,andν[O12(2Π1/2→X2Π3/2)]=182.568cm1,respectively.Allthespectroscopicdataforelectronicstates2Π1/2and2Π3/2aregivenforthefirsttime.
简介:YBa2Cu3Ox(YBCO)thinfilmsgrownondifferentsubstrateswithand/orwithoutEu2CuO4(ECO)bufferlayerwereinvestigatedbyX-raywideanglediffraction,reflection,diffusescatteringandtopography.TheresultsshowthatfortheyttriastabilizedZrO2(YSZ)substrate,thepresenceofanECObufferlayerimprovesthecrystallinequalityoftheYBCOfilm,whileanegativeeffectisobservedfortheSrTiO3(STO)substrate.ThelateralcorrelationlengthforasamplegrownonaYSZsubstratewithECObufferLayerismuchgreaterthangrownonanSTOsubetrate.TheSTOsubstrateusedhasmosaicstructure.2001ElsevierScienceB.V.Allrightsreserved.
简介:介绍了全面禁止核试验条约(CTBT)中涉及的放射性氙同位素及其来源、核爆炸产生放射性氙同位素特征和CTBT大气放射性氙监测技术,重点总结了CTBT中大气放射性氙的取样、测量、事件性质识别和源项解析等技术的最新进展。在氙监测设备方面,已有3套商业化的氙监测系统可供采购,且氙同位素取样效率和探测灵敏度已远超临时技术秘书处设定的技术指标要求;在放射性氙同位素活度测量与能谱分析方面,Si-PIN新型探测器研究取得较大进展,建立了放射性氙数据分析软件;在氙监测事件性质识别方面,建立了Kalinowski判据模型;在大气输运模拟研究与应用方面,基于FLEXPART模型开发了Web-Grape和Web-GrapeIBS软件。但从实际监测效果看,有效获取敏感核素对及核素比,并依此提供确凿核爆炸证据的能力尚显不足。下一步工作应聚焦在氙同位素探测灵敏度提升、氙监测事件识别及溯源等研究上。
简介:Inthefarfieldoftheintensitydistributionofthebeamdeliveredbyatwo-stagetransient–collisionalexcitationX-raylaser(XRL),anon-expectedinterferencepatternthatisstablefromshottoshothasbeendiscovered.Itisdemonstratedthattheinterferenceiscausedbytheemergenceofanimaginarysourceintheamplifyingplasma,whichisphasematchedtotheradiationofthegenerator.TheobservedphenomenoniscalledanX-raycoherentmirage.Toexplaintheobtainedresults,anewtheoreticalapproachisdeveloped.ThebasicessentialconditionsforformationoftheX-raymirageareformulated,andpossibleapplicationsarediscussed.Thispaperdetailstheexperiments,includingtheformulationofthenecessaryandsufficientconditionsforformationoftheX-raymirage,andpossibleapplicationsarediscussed.
简介:ThestatusoftheEuropeanX-rayFree-ElectronLaser(EuropeanXFEL),underconstructionnearHamburg,Germany,isdescribed.ThestartofoperationsoftheLCLSatSLACandofSACLAinJapanhasalreadyproducedimpressivescientificresults.TheEuropeanXFELfacilityispoweredbya17.5GeVsuperconductinglinearacceleratorthat,comparedtothesetwooperatingfacilities,willgeneratetwoordersofmagnitudemorepulsespersecond,upto27000.Itcanthereforesupportmodesofoperationswitchingthebeamupto30timespersecondamongthreedifferentexperiments,providingeachofthemwiththousandsofpulsespersecond.Thescientificpossibilitiesopenedupbythesecapabilitiesarebrieflydescribed,togetherwiththecurrentinstrumentaldevelopments(inoptics,detectors,lasers,etc.)thatarenecessarytoimplementthisprogram.
简介:X-γradiationbelongtotheionizingradiation.Ionizingradiationsinkstoenergyinorganismbutproduceadisservicetotheorganism.Justasmedicine,thedisserviceoftheradiationtowardsOrganismisdecidedbytoacceptradiationquantify,theradiationquantifywasnameddose.Radiationprotection'sbasicmissionsistowanttoresultthedosetofixquantify.InthissurveythedoseatworkplaceanditssurroundingsenvironmentsofHL-2Adevicewasmeasuredandtheassessmentwasgivenout.
简介:SmallangleX-rayscatteringexperimentshavebeenperformedtostudythemicrostructureofmessoporoussilicameterialspreparedbycondensationoftetraethylorthosilicateusingnonionicalkylpolyethyleneoxide(AEO9)andioniccetyltrimethylammoniumbromide(CTAB)surfactantastemplates.Itistheporeswithinthenanometrerangethatproducethemaincattering.ThescatteringofthepuresilicasystemsobeyPorod’slaw.Thismaybebecausethetemplatesproducesomeadditionalscatteringbackgroundandthenmakethescatteringofporesdistorted.TheresultsshowthatthefullremovaloftemplatesfromtheporesofthematerialsbySoxhletextractionisveryeasyforAEO9,butitisdifficultforCTAB.Thepositivedeviationcorrectionisalsoperfromed.