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166 个结果
  • 简介:QuantumdynamicscalculationsforthetitlereactionH(2S)+S2(X3-Σg)→SH(X2Π)+S(3P)areperformedbyusingagloballyaccuratedoublemany-bodyexpansionpotentialenergysurface[J.Phys.Chem.A1155274(2011)].TheChebyshevrealwavepacketpropagationmethodisemployedtoobtainthedynamicalinformation,suchasreactionprobability,initialstate-specifiedintegralcrosssection,andthermalrateconstant.Itisfoundnotonlythatthereisareactionthresholdnear0.7eVinbothreactionprobabilitiesandintegralcrosssectioncurves,butalsothatboththeprobabilityandcrosssectionincreasefirstlyandthendecreaseasthecollisionenergyincreases.Theexistenceoftheresonancestructureinboththeprobabilityandcrosssectioncurvesisascribedtothedeeppotentialwell.Thecalculationoftherateconstantrevealsthatthereactionoccurringonthepotentialenergysurfaceoftheground-stateHS2isslowtotakeplace.

  • 标签: 反应概率 动力学计算 上海 量子 表面 截面曲线
  • 简介:关于X光折射率小于1的讨论=AdiscussionontherefractiveindexofX—raylessthan1[刊,中]/谭业武(滨州师范专科学校物理系)∥大学物理.—1994.13(11).—22—23,21从几个不同的方面讨论了X光的折射率,并通过

  • 标签: 光折射率 大学物理 师范专科学校 物理系 滨州 射线
  • 简介:O434.2//TN232001021486紫外线技术在军事上的应用研究=Studyofapplicationofultravioletteehnolgoytomilitaryaffairs[刊,中]/张忠廉,刘榴娣(北京理工大学光电工程系.北京(100081))//光学技术.-2000,26(4).-289-293,296介绍了紫外线在军事上的应用和紫外波段光电探测器件的发展情况以及国内外紫外技术在军事上应用概况,提出了在军事应用方面如何对紫外线技术作进一步研究的建议。(李瑞琴)

  • 标签: 紫外线技术 发展情况 光学技术 光电工程 光电探测器件 应用研究
  • 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。

  • 标签: X射线源 斑点 强流电子束 直线感应加速器 高能X射线 测量
  • 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.

  • 标签: 分子结构 势能函数 自旋轨道耦合 电子态
  • 简介:YBa2Cu3Ox(YBCO)thinfilmsgrownondifferentsubstrateswithand/orwithoutEu2CuO4(ECO)bufferlayerwereinvestigatedbyX-raywideanglediffraction,reflection,diffusescatteringandtopography.TheresultsshowthatfortheyttriastabilizedZrO2(YSZ)substrate,thepresenceofanECObufferlayerimprovesthecrystallinequalityoftheYBCOfilm,whileanegativeeffectisobservedfortheSrTiO3(STO)substrate.ThelateralcorrelationlengthforasamplegrownonaYSZsubstratewithECObufferLayerismuchgreaterthangrownonanSTOsubetrate.TheSTOsubstrateusedhasmosaicstructure.2001ElsevierScienceB.V.Allrightsreserved.

  • 标签: 微观结构 X射线衍射分析 YBa2Cu3O7薄膜 钇钡铜复合氧化物薄膜 缓冲层 薄膜生长
  • 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。

  • 标签: X射线结构分析 软件 数据处理
  • 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。

  • 标签: 小角X射线散射 多孔材料 模糊数据 结构分析 解析方法 SAXS
  • 简介:Inthefarfieldoftheintensitydistributionofthebeamdeliveredbyatwo-stagetransient–collisionalexcitationX-raylaser(XRL),anon-expectedinterferencepatternthatisstablefromshottoshothasbeendiscovered.Itisdemonstratedthattheinterferenceiscausedbytheemergenceofanimaginarysourceintheamplifyingplasma,whichisphasematchedtotheradiationofthegenerator.TheobservedphenomenoniscalledanX-raycoherentmirage.Toexplaintheobtainedresults,anewtheoreticalapproachisdeveloped.ThebasicessentialconditionsforformationoftheX-raymirageareformulated,andpossibleapplicationsarediscussed.Thispaperdetailstheexperiments,includingtheformulationofthenecessaryandsufficientconditionsforformationoftheX-raymirage,andpossibleapplicationsarediscussed.

  • 标签: COHERENT seeded BEAMS MIRAGE PHASE-MATCHING X-RAY
  • 简介:ThestatusoftheEuropeanX-rayFree-ElectronLaser(EuropeanXFEL),underconstructionnearHamburg,Germany,isdescribed.ThestartofoperationsoftheLCLSatSLACandofSACLAinJapanhasalreadyproducedimpressivescientificresults.TheEuropeanXFELfacilityispoweredbya17.5GeVsuperconductinglinearacceleratorthat,comparedtothesetwooperatingfacilities,willgeneratetwoordersofmagnitudemorepulsespersecond,upto27000.Itcanthereforesupportmodesofoperationswitchingthebeamupto30timespersecondamongthreedifferentexperiments,providingeachofthemwiththousandsofpulsespersecond.Thescientificpossibilitiesopenedupbythesecapabilitiesarebrieflydescribed,togetherwiththecurrentinstrumentaldevelopments(inoptics,detectors,lasers,etc.)thatarenecessarytoimplementthisprogram.

  • 标签: FEMTOSECOND LASERS and APPLICATIONS free-electron LASERS
  • 简介:Inthiswork,webrieflydiscussanovelclassofmodifiedgravitylikef(T,TG)gravity.Inthisbackground,weassumethenewagegraphicversionofpilgrimdarkenergyandreconstructf(T,TG)modelsfortwospecificvaluesofs.Wealsodiscusstheequationofstateparameter,squaredspeedofsoundandwDE-wDEplaneforthesereconstructedf(T,TG)models.Theequationofstateparameterprovidesphantom-likebehavioroftheuniverse.ThewDE-wDEplanealsocorrespondstoΛCDMlimit,thawingandfreezingregionsforbothmodels.

  • 标签: f(T TG) GRAVITY PILGRIM DE models
  • 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。

  • 标签: 合金铸件 射线检测技术 曲面 薄壁 金属模铸造
  • 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。

  • 标签: 脉冲星导航 X射线探测 大灵敏面 空间背景辐射 粒子甄别
  • 简介:X-γradiationbelongtotheionizingradiation.Ionizingradiationsinkstoenergyinorganismbutproduceadisservicetotheorganism.Justasmedicine,thedisserviceoftheradiationtowardsOrganismisdecidedbytoacceptradiationquantify,theradiationquantifywasnameddose.Radiationprotection'sbasicmissionsistowanttoresultthedosetofixquantify.InthissurveythedoseatworkplaceanditssurroundingsenvironmentsofHL-2Adevicewasmeasuredandtheassessmentwasgivenout.

  • 标签: X-γ辐射剂量 HL-2A 电离辐射 安全评价 磁约束受控热核聚变
  • 简介:SmallangleX-rayscatteringexperimentshavebeenperformedtostudythemicrostructureofmessoporoussilicameterialspreparedbycondensationoftetraethylorthosilicateusingnonionicalkylpolyethyleneoxide(AEO9)andioniccetyltrimethylammoniumbromide(CTAB)surfactantastemplates.Itistheporeswithinthenanometrerangethatproducethemaincattering.ThescatteringofthepuresilicasystemsobeyPorod’slaw.Thismaybebecausethetemplatesproducesomeadditionalscatteringbackgroundandthenmakethescatteringofporesdistorted.TheresultsshowthatthefullremovaloftemplatesfromtheporesofthematerialsbySoxhletextractionisveryeasyforAEO9,butitisdifficultforCTAB.Thepositivedeviationcorrectionisalsoperfromed.

  • 标签: 小角X射线散射分析 SAXS 中孔硅石 结构分析 样品