简介：应用于高能闪光X光照相技术的X射线源主要是强流电子束与重金属靶相互作用产生的韧致辐射，一般应用电子直线感应加速器（LIA）产生强流电子束，电子束被聚焦到一个很小的焦斑后打靶。进行闪光照相时，X射线斑点大小是一关键参量，直接影响成像的分辨能力。由于高能X射线的强穿透能力和强辐射环境，传统的小孔成像法难以应用。

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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：分析了核热推进NTP（nuclearthermalpropulsion）反应堆关键技术及现状，介绍了核热推进反应堆技术在空间推进领域的应用，总结对比了美国、俄罗斯现有核热推进反应堆设计方案的主要参数和特性，并对未来航天器用核热推进反应堆的发展方向和应用前景进行了探讨。

简介：在模拟计算高温系统中子输运问题时，为了快速在线处理中子核截面，基于多普勒展宽原理，发展了一种修正多普勒展宽方法。通过在低能区引入低能截面修正因子、调整计算方法及合理设置数值积分计算参数等，进行了数值算法优化，探讨了NJOY程序对高能区中子截面展宽的限制及影响，在自主开发的蒙特卡罗输运程序中实现了中子截面的快速在线展宽处理，并比较了NJOY程序与本文程序计算的截面数据。结果表明，本文程序给出的高温展宽截面准确性高，计算效率能满足快速在线展宽需求，可高效处理在线中子截面展宽问题。

简介：通过软件实现了用ＰＣ机调用日本Ｒｉｇａｋｕ公司生产的Ｄ／ｍａｘ一类Ｘ射线衍射仪测量数据，利用ＰＣ机的复杂计算功能，使原有仪器也可以进行新的结构分析工作，扩展了仪器的功能。

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简介：小角X射线散射(SAXS)是研究多孔材料结构的一种有效方法．可得到孔径分布、平均孔径、比表面、界面层厚度、分形维数等许多微结构信息．SAXS理论公式基于点状光源(针孔准直)，但实践中则大多采用长狭缝准直条件．简要综述了SAXS在长狭缝准直条件下直接应用模糊强度进行煤、炭、二凝胶、分子筛等多孔材料结构解析的方法、并与针孔准直进行了对比。

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：Ｇｒｏｕｎｄ－ｓｔａｔｅＰｒｏｐｅｒｔｉｅｓｏｆＤｏｕｂｌｙ－ｍａｇｉｃＮｕｃｌｅｕｓ１００Ｓｎ￥ＷｅｎＷａｎｘｉｎ；ＪｉｎＧｅｎｍｉｎｇａｎｄＺｈｏｎｇＪｉｑｕａｎＴｈｅｄｏｕｂｌｙ－ｍａｇｉｃｎｕｃｌｅｉ１００Ｓｎｗａｓｐｒｏｄｕ?..

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简介：Co(II)-salenwasencapsulatedinMIL-100(Cr)metalorganicframeworkby"shipinabottle"tosynthesizeanewelectrocatalyst,Cosalen@MIL-100(Cr).ThematerialwascharacterizedbyXRD,FT-IR,UV-VisandN2-adsorption.TheCosalen@MIL-100(Cr)modifiedglassycarbonelectrodeexhibitsawell-definedreductionpeakatthepotentialof–0.21Vtowardtheoxygenreductionreaction(ORR)bycyclicvoltammetry(CV)inpH=6.84phosphatebuffer.Almost400mVpositiveshiftofpotentialatCosalen@MIL-100(Cr)modifiedelectrodeforORRcomparedwiththatatbareglassycarbon,indicatesthatCosalen@MIL-100(Cr)possessesexcellentelectrocatalyticactivity.ThetransferrednumberofelectronsforORRwasdeterminedbychronocoulometry.TheresultsuggeststhattheintroductionofCo(II)-salencomplexintoMOFincreasestheelectrocatalyticactivityviaafour-electronreductionpathway.Furthermore,thiselectrocatalystexhibitsgoodstabilityandreproducibility.

简介：Theadsorptionandelectronicpropertiesofisolatedcobaltphthalocyanine(CoPc)moleculeonanultrathinlayerofNaClhavebeeninvestigated.High-resolutionSTMimagesgiveadetailedpictureofthelowestunoccupiedmolecularorbital(LUMO)ofanisolatedCoPc.ItisshownthattheNaClultrathinlayerefficientlydecouplestheinteractionofthemoleculesfromtheunderneathmetalsubstrate,whichmakesitanidealsubstrateforstudyingthepropertiesofsinglemolecules.Moreover,strongdependenceoftheappearanceofthemoleculesonthesamplebiasintheregionofrelativelyhighbias(>3.1V)isascribedtotheimagepotentialstates(IPSs)ofNaCl/Cu(100),whichmayprovideuswithapossiblemethodtofabricatequantumstoragedevices.

简介：总结比较了国内外利用高亮度γ源进行核共振荧光（nuclearresonancefluorescence,NRF）研究的最新成果,从理论上分析了NRF的反应截面,介绍了利用Geant4对NRF过程的蒙特卡罗模拟,通过比较不同激发光源下得到的NRF实验结果,说明了激光康普顿散射源在NRF研究中的优势。介绍了NRF实验中常用的背散射探测方法和透射探测方法,分析比较了不同探测器的性能。最后,展望了未来NRF的研究方向。

简介：薄壁曲面铅合金铸件（简称铅铸件）采用砂模或金属模铸造，经机械加工成壁厚约3-4mm的变壁厚曲面回转体，要求精加工后内部不得有大于φ0．4mm以上的渣孔类缺陷。

简介：立足实用化脉冲星导航技术需要，梳理了现有脉冲星导航探测方法及研究进展，结合探测器运行空间环境，分析了探测器指标，比较了现有天基x射线探测方法、载荷特点以及各探测技术存在的不足，并对空间辐射环境去噪方法进行了评述，对后续脉冲星导航探测方法构建及装置研制提出了几点建议。

简介：X-γradiationbelongtotheionizingradiation.Ionizingradiationsinkstoenergyinorganismbutproduceadisservicetotheorganism.Justasmedicine,thedisserviceoftheradiationtowardsOrganismisdecidedbytoacceptradiationquantify,theradiationquantifywasnameddose.Radiationprotection'sbasicmissionsistowanttoresultthedosetofixquantify.InthissurveythedoseatworkplaceanditssurroundingsenvironmentsofHL-2Adevicewasmeasuredandtheassessmentwasgivenout.