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

简介：分析了X射线辐照电缆的物理过程,建立了基于有限元方法的二维诺顿等效电流源计算模型,将泊松方程、电场强度、电荷守恒方程等求解过程转换为矩阵和向量运算,并利用PETSc程序包编程计算,模拟了辐射感应电导率和间隙效应对屏蔽电缆X射线辐照响应的影响。结果显示,仅考虑辐射感应电导率效应时,随着X射线注量的增加,诺顿等效电流源逐渐趋于饱和,波形宽度变窄,并逐渐变为双极性波形。仅考虑间隙效应时,诺顿等效电流源幅度与间隙宽度近似成正比;间隙效应会大幅抵消辐射感应电导率效应的影响,诺顿等效电流源幅度仍近似正比于间隙宽度。该方法实现了电缆X射线辐照非线性效应的模拟,并将计算对象扩展到屏蔽多导体电缆。

简介：TheadsorptionofCOonPtgroupmetals,asamostfundamentalelementaryreactionstep,hasbeenwidelystudiedincatalysisandelectrocatalysis.Particularly,thestructuresofCOonPt(111)havebeenextensivelyinvestigated,owingtoitsimportancetobothfundamentalandappliedcatalysis.Yet,muchlessisknownregardingCOadsorptiononaPt(111)surfacemodulatedbysupportedoxidenanostructures,whichisofmorerelevancetotechnicalcatalysis.Wethusinvestigatedthecoverage-dependentadsorptionofCOonaPt(111)surfacepartiallycoveredbyFeOxnanostructures,whichhasbeendemonstratedasaremarkablecatalystforlow-temperatureCOoxidation.Wefoundthat,duetoitsstrongchemisorption,thecoverage-dependentstructureofCOonbarePtisnotinfluencedbythepresenceofFeOx.But,oxygen-terminatedFeOxnanostructurescouldmodulatethediffusivityofCOattheirvicinity,andthusaffecttheformationoforderedCOsuperstructuresatlowtemperatures.Usingscanningtunnelingmicroscopy(STM),weinspectedthediffusivityofCO,followedthephasetransitionsofCOdomains,andresolvedthemoleculardetailsofthecoverage-dependentCOstructures.OurresultsprovideafullpictureforCOadsorptiononaPt(111)surfacemodulatedbyoxidenanostructuresandshedlightsontheinter-adsorbateinteractiononmetalsurfaces.

简介：以Li_2B_4O_7、LiBO_2和LiF（质量比为45∶10∶5）为混合熔剂,NH_4NO_3为氧化剂,LiBr为脱模剂,熔融制作样片,采用硅质砂岩、石英岩标准样品和配制标准样品作为校准样品,建立了熔融制样-X射线荧光光谱法（XRF）测定硅石中主次量成分（SiO_2、Al_2O_3、TFe_2O_3、MgO、CaO、K_2O、MnO、TiO_2、P_2O_5）的快速分析方法。对样品制备以及分析测试过程中的条件进行了优化,在最优条件下,对标准样品（GBW03112、GBW07835）进行重复测定,相对标准偏差RSD〈2%。同时对3个混合配制的硅石标准样品进行分析,结果与参考值无显著性差异。

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简介：Magnetoplasmonicsensorsareattractivecandidatesforultrasensitivechemicalandbiomedicalsensorapplications.Avarietyofferromagneticmetalthinfilmshavebeenusedformagnetoplasmonicdeviceapplications,yetthedependenceofsensorperformanceontheopticalandmagneto-opticalpropertiesofferromagneticmetalmaterialshasbeenrarelystudied.Inthiswork,wereportthestudyofenhancedmagneto-opticalKerreffect（MOKE）andsensingperformanceinAu∕FexCo1-xbilayermagneto-opticalsurfaceplasmonresonance（MOSPR）transducers.TheopticalconstantsofFexCo1-x（x=0,0.29,0.47,0.65,and1）inasputter-depositedAu∕FexCo1-xdevicearecharacterizedbytheattenuatedtotalinternalreflection（ATR）method.FexCo1-xthinfilmsshowdifferentMOKEsasafunctionofthechemicalconcentration,withthehighesttransverseMOKEsignalobservedinFe0.7Co0.3.Indexsensingperformanceiscloselyrelatedtothematerial’sopticalandmagneto-opticalconstants.BystudyingthesensingperformanceintheparameterspaceoftheAu∕FexCo1-xbilayerthicknesses,thehighestsensitivityisfoundtobe0.385（theoretical）and0.306RIU-1（experimental）intheAu∕Fe0.7Co0.3MOSPRdevices.OurresearchhighlightstheinfluenceoftheopticalpropertiesofferromagneticmaterialtodevicesensitivityinMOSPRtransducers.ThehighsensitivityinAu∕FexCo1-xMOSPRdevicesmakethesestructuresattractivecandidatesforchemicalandbiomedicalsensingapplications.

简介：通过研究丁老师的教学实录,分析其教学特色：问题融入情境,提升导入质量;问题驱动探究,注重自主设计.从而反思教学应该抓住在建构数学的过程中驱动学生思考和在方法策略的选择中优化解决路径.

简介：针对多种类不锈钢多元素成分解析问题,应用X射线荧光光谱分析软件UniQuant,采用扩展基本参数法对多元不锈钢、双相不锈钢进行光谱干扰校正和基体校正,重新设定和优化多元不锈钢基体元素的测试条件,计算背景因子、杂质因子、谱线灵敏度系数和光谱重叠系数,测定Si、Mn、S、P、Ni、Cr、Cu、Mo、V、Al、Ti、Nb、Co、Ta、Fe的相对标准偏差在0.04%-3.8%,Ca、Zr、W、As、Sb、Sn的相对标准偏差在5.4%-20.3%,未知样品检测值与认定值比对结果相当理想,Ni、Cr的平均偏差小于0.05%,可以用很少标准样品实现各类型不锈钢多元素成分准确检测,检测范围宽,适用性好。

简介：LiMn2O4andLiNixAlyMn2-x-yO4（x=0.50;y=0.05-0.50）powdershavebeensynthesizedviafacilesolgelmethodusingBehenicacidasactivecheiatingagent.Thesynthesizedsamplesaresubjectedtophysicalcharacterizationssuchasthermogravimetricanalysis（TG/DTA）,X-raydiffraction（XRD）,Fouriertransforminfraredspectroscopy（FT-IR）,field-emissionscanningelectronmicroscopy（FESEM）,transmissionelectronmicroscopy（TEM）andelectrochemicalstudiesviz.,galvanostaticcyclingproperties,electrochemicalimpedancespectroscopy（EIS）anddifferentialcapacitycurves（dQ/dE）.FingerprintXRDpatternsofLiMn2O4andLiNixAlyMn2-x-yO4fortifythehighdegreeofcrystallinitywithbetterphasepurity.FESEMimagesoftheundopedpristinespinelillustrateuniformsphericalgrainssurfacemorphologywithanaverageparticlesizeof0.5μmwhileNidopedparticlesdepictthesphericalgrainsgrowth（50nm）withice-cubesurfacemorphology.TEMimagesofthespinelLiMn2O4showstheuniformsphericalmorphologywithparticlesizeof（100nm）whilelowlevelofAl-dopingspinel（LiNio.5Alo.05Mn1.45O4）displayingcloudyparticleswithagglomeratedparticlesof（50nm）.TheLiMn2O4samplescalcinedat850℃deliverthedischargecapacityof130mAh/ginthefirstcyclecorrespondsto94%coiumbicefficiencywithcapacityfadeof1.5mAh/g/cycleovertheinvestigated10cycles.Amongallfourdopantcompositionsinvestigated,LiNi0.5Al0.05Mn1.45O4deliversthemaximumdischargecapacityof126mAh/gduringthefirstcycleandshowsthestablecyclingperformancewithlowcapacityfadeof1mAh/g/cycle（capacityretentionof92%）overtheinvestigated10cycles.ElectrochemicalimpedancestudiesofspinelLiMn2O4andLiNi0.5Al0.05Mn1.45O4depictthehighandlowrealpolarizationof1562and1100Ω.

简介：采用粉末压片法制样,建立了波长色散X射线荧光光谱法快速测定生石灰粉中氧化钙、二氧化硅的分析方法。由于没有国家标准样品,采用自制生石灰粉标准样品绘制工作曲线。考察了样品粒度及吸潮对分析结果的影响。实验表明,在样品粒度为74μm、压样机压力为12MPa、压制时间为45s的制样条件下荧光计数率最稳定,在30min内测定样品效果最佳。采用α理论系数法和经验系数法相结合校正基体影响。对同一生石灰粉样品进行精密度实验,各组分的相对标准偏差（RSD,n=11）在0.04%~0.43%。测定了5个生石灰粉样品,所得结果与常规化学分析方法测定值相符。

简介：我们在Mn50Ni40SnSbx(x=1，2，3，和4)合金。所有准备样品在房间温度与空间组一起展出B2类型结构。Sb的替换增加原子价电子集中并且减少联合起来的房间体积。作为结果，当x增加，magnetostructural转变向更高的温度很快变。在在不同磁场变化下面的磁性的熵的变化在这转变附近被探索。等温的磁化曲线展出典型metamagnetic行为，显示magnetostructural转变能被一个磁场导致。悦耳的martensitic转变和磁性的熵变化建议那Mn50Ni40SnSbx合金是应用在的吸引人的候选人固态制冷。