简介：【本节需学习的内容】本节教材通过观察和实验，知道白光是由色光组成的．比较色光混合得出一些实验结论，并能理解物体呈现的颜色由什么决定，知道光具有能量．

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.

简介：SmallangleX-rayscatteringexperimentshavebeenperformedtostudythemicrostructureofmessoporoussilicameterialspreparedbycondensationoftetraethylorthosilicateusingnonionicalkylpolyethyleneoxide(AEO9)andioniccetyltrimethylammoniumbromide(CTAB)surfactantastemplates.Itistheporeswithinthenanometrerangethatproducethemaincattering.ThescatteringofthepuresilicasystemsobeyPorod’slaw.Thismaybebecausethetemplatesproducesomeadditionalscatteringbackgroundandthenmakethescatteringofporesdistorted.TheresultsshowthatthefullremovaloftemplatesfromtheporesofthematerialsbySoxhletextractionisveryeasyforAEO9,butitisdifficultforCTAB.Thepositivedeviationcorrectionisalsoperfromed.

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简介：ThispaperresentsanewX-rayimagingmethodswingLaminography(SL)thatissuitalbletoperformnon-destructivetestingontheslender-shapedmulti-layersamples.ComputersimulationsaremadetocomparethelimitedprojectionsinSLandtheprincipleofchoosingOptimalProjectionAngularRegion(OPAR)isdiscussed.Theexperimentonatwo-layerPrintedCircuitsBoardshowsthatSLwith120°swinganglesdistributedinOPARcangettheseparatedimagesofeachlayer.

简介：Energylevels,radiativerates,oscillatorstrengthsandlinestrengthsarereportedfortransitionsamongthelowest97levelsofthe(1s22s22p6)3s23p2,3s23p3d,3s3p3,3p4,3s3p23d,and3s23d2configurationsofRbXXIV.AmulticonfigurationDirac–Fock(MCDF)methodisadoptedforthecalculations.Radiativerates,oscillatorstrengths,andlinestrengthsareprovidedforallelectricdipole(E1),magneticdipole(M1),electricquadrupole(E2),andmagneticquadrupole(M2)transitionsfromthegroundleveltoall97levels,althoughcalculationsareperformedforamuchlargernumberoflevels.Toachievetheaccuracyofthedata,comparisonsareprovidedwithsimilardataobtainedfromtheFlexibleAtomicCode(FAC)andalsowiththeavailabletheoreticalandexperimentalresults.Ourenergylevelsarefoundtobeaccuratetobetterthan1.2%.WavelengthscalculatedarefoundtolieinEUV(extremeultraviolet)andx-rayregions.Additionally,lifetimesforall97levelsareobtainedforthefirsttime.

简介：根据实际应用需求,设计了一种X波段宽带圆波导耦合器。通过理论计算与数值模拟优化,实现频率9.3GHz时,耦合度约为一71.2dB;频率范围为9～10GHz时,耦合曲线平坦度小于0.3dB,可显著降低微波功率测量不确定度。为了提高耦合器的功率容量,对结构进行了改进,在耦合孔处进行了倒圆角处理。倒圆角半径为1mm时,耦合孔最高场强降低了52%,功率容量得到提高。

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简介：【本节需学习的内容】本节教材由“光由空气射入水中时的折射情况”和“光通过玻璃砖时的折射特点”两部分组成，主要是通过实验观察光的折射现象和折射的特点．

简介：利用单片机，集数据采集、存贮、显示结果为一体，成功地显示了偏振光的光强分布，并可测量其相对强度和照度．

简介：O43196010002单模辐射场与N个原子相互作用理论=Theoryofasingle—moderadiationfieldinteractionwithNatoms[刊,中]/张登玉(湖南衡阳师范专科

简介：讨论了用换向法测量gF时，外加水平磁场调制电压的取值范围，给出了区分光抽运信号和磁共振信号的方法。

简介：采用共孔径发射和接收技术可使激光信标系统结构紧凑、控制简单。在激光的共孔径发射和接收中使用偏振耦合分光方法有分光效率高、简单可靠等优点。但是，组成地平式折轴望远镜的反射镜对s光和p光的相位延迟有差异，望远镜旋转造成的激光偏振态变化更严重地影响了偏振分光的接收效率。要保持较高的接收效率，就需要对激光相位进行动态补偿。

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.