简介：电子结构和硫在钾dihydrogen磷酸盐(KDP)代替的黄磷的几何分发被第一原则的计算调查。点缺点在精力差距下面变窄到大约4.9eV，相应于在修正以后的355nm的二光子的吸收。这能在KDP晶体解释激光损坏抵抗的减少。而且，缺点扭曲水晶结构并且削弱契约，特别O-H契约，这些契约可以因此是第一个地点在激光照耀下面裂开。[从作者抽象]

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简介：该规划的目的是重新研究物理教育的内容和结构，这是由于在三个方面有了重大的发展：①过去的三十年里，物理知识爆炸性地增长；③认知心理学的研究，对学习进程有了新的认识，③计算机技术及其功能不断提高。

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简介：Uptothisdate,researchersarestillfacingdifficultiestoexpandthetechnologyofdirectmethanolfuelcells(DMFCs)becauseofthehighoverpotentialrequiredtooxidizethemethanolanditsrelativelypoorperformanceduetoCOpoisoningoftheleading-highcostanodecatalyst.Inlinewiththis,wehavesuccessfullymodifiedthemorphologicalstructureandcompositionoflowcostcobaltbased-metaloxides,MCo2O4(M=ZnandNi),withthesimpleandnobleuseofpolyvinylpyrrolidone(PVP)asgrowthmodifierandsurfacestabilizerduringthesynthesisofnanoparticlesinourpreviousreports,whichshownhighelectrocatalyticactivityandstrongstability.DuetothegoodperformanceofourPVPmodifiedMCo2O4towardspseudocapacitorandoxygenevolutionreactionapplications,wedecidedtoextendourresearchstudytomethanoloxidationreaction.Remarkably,PVPmodifiedNiCo2O4electrodedirectlygrownonnickelfoamsubstrateviaasimplehydrothermalprocessexhibitedbetterperformancecomparedwithPVPmodifiedZnCo2O4andNiCo2O4withoutPVP.Ithadobtainedaremarkablylowonsetpotentialof0.285Vandhighcurrentdensityof280mAcm-2,andshowngreatstabilityandhighpoisontoleranceduringacontinuousCVcyclingandChronoamperometrytest,whichattainedhighefficiencyof86.86%and98.52%,respectively.ThesepositiveresultsofPVPmodifiedNiCo2O4electrodetowardsMORmightbeattributedtoitshierarchical3Dnanostructureswithhighlymesoporoussurfaceandlargesurfaceareawhichmayhaveprovidednumerouselectroactivesites,andtheexceptionalcorrosionstabilityofNiCo2O4electrodeinalkalinesolution.

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简介：Wehavedevelopedanewradiographysetupwithashort-pulselaser-drivenx-raysource.Usingaradiographyaxisperpendiculartobothlong-andshort-pulselasersallowedoptimizingtheincidentangleoftheshort-pulselaseronthex-raysourcetarget.Thesetuphasbeentestedwithvariousx-raysourcetargetmaterialsanddifferentlaserwavelengths.Signaltonoiseratiosarepresentedaswellasachievedspatialresolutions.ThehighqualityofourtechniqueisillustratedonaplasmaflowradiographobtainedduringalaboratoryastrophysicsexperimentonPOLARs.

简介：Itisimpossibletodirectlyanalyzethemicrostructureofspin-valvemultilayersbasedonNi,F,CuandMnbyaconventionalX-raydiffractiontechniquebecausethelatticeparameterandatomicsatteringfactorsofthemareveryclose.Tosolvethisproblem,weuseanx-rayanomalousdiffractiontechniquetocharacterizethemicrostructuresofthe[Ni80Fe20/Fe50Mn50]15and[Ni80Fe20/Cu]15superlatticesystems.Theresultsshowthatmorediffractionpeaksandhigherinternsityinthereflectivetyprofileareobservedwhentheincidentenergyisclosetotheabsorptionedgeofthelighterelement(Mn)in[Ni80Fe20/Fe50Mn50]15multilayersystemsandtotheabsorptionedgeoftheheavierelement(Cu)inthe[Ni80Fe20/Cu]15multilayersystems.Theinterfaceandperiodicstructureof[Ni80F20/Fe50Mn50]15aremoreperfectthanthatofthe[Ni80Fe20/Cu]15superlattices.Theaboveresultsaredisussedinthispaper.

简介：Small-angleX-rayscattering(SAXS)usingsynchrotronradiationasX-raysourcehasbeenemployedtocharactcizcthemicroscopicstructrureoforgano-modifiedmesoporousmolecularsieves(organo-MSU-X)preparedbyaone-pottemplate-directedsynthesis.ItisshownthattheSAXSprofileishardlyconstantwithPorod’slawshowinganegativeslope,i.e.,negativedeviation.Thissuggeststhatthereisdiffuseinterfaciallayerlocatedbetweentheporesandthematrix.Thissuggeststhattheorganicgroupsremaincovalentlylinkedtothematrix,asindicatedby^29SiCPMASNMRandFT-IR.Theaveragethicknessoftheinterfaciallayerwasfoundtobeabout1nmforeachofthethreesampleswithdifferentkindsandthesameamounts(20?oforganicgroups.Thiskindofmaterialhasalsobeenprovedtopossessbothsurfaceandmassfractalstructureoftheamophousporoussilicamaterials.2001ElsevierScienceB.V.Allrightsreserved.

简介：ThispaperprovidesareviewonsampleinjectorswhichareprovidedatSPring-8AngstromCompactfreeelectronLAser(SACLA)forconductingserialmeasurementina‘diffract-before-destroy'schemeusinganx-rayfreeelectronlaser(XFEL).VersatileexperimentalplatformsatSACLAareabletoacceptvarioustypesofinjectors,amongwhichliquidjet,dropletandviscouscarrierinjectorsarefrequentlyutilized.Theseinjectorsproducedifferentformsoffluidtargetssuchasaliquidfilamentwithadiameterintheorderofmicrometer,micro-dropletsynchronizedtoXFELpulses,andslowlyflowingcolumnofhighlyviscousfluidwitharatebelow1μLmin-1.Characteristicsandapplicationsoftheinjectorsaredescribed.

简介：O434．122006065468强脉冲软X光辐照薄塑料闪烁体发光特性研究=LinearluminescenceforthinplasticscintillatorsunderintensesoftX-rayirradiation[刊,中]/宁家敏(中物院核物理与化学研究所．四川,绵阳(621900)),蒋世伦…//强激光与粒子束．—2006,18(7)．—1215-1218介绍了Z-pinch实验用软X光功率仪的测量原理,利用“强光一号”产生的强脉冲软X光对薄塑料闪烁体((?)40min×0．1mm)进行了辐照。实验中,采用两套软X光功率仪并安装在同一个大法兰面上．其中一套作为标准系统,参数保持不变,另一套系统的狭缝宽度逐渐增加,以改

简介：在北京同步辐射装置上应用同步辐射X射线小角散射技术研究TATB样品微孔状况，分析了微孔结构参数的变化。采用不同制备工艺(机械研磨、化学合成、气流细化、全结晶、粉碎)和不同存放时间的TATB粉末样品共计7份。

简介：介绍了辐射模拟加速器辐射场中脉冲X射线能谱的几种常用测量方法，阐述了基本原理、测量装置的典型系统组成、主要参数特性、技术发展状况和研究进展，描述了各种方法的优缺点和适用范围。以吸收法为例，综述了解谱技术的发展状况，并描述了多种解谱方法的特点。最后，重点介绍了西北核技术研究所脉冲X射线能谱测量的进展，并对测量系统抗噪和散射控制技术进行了评述。结合现有条件和技术成熟度，对今后工作的发展方向进行了展望。

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