简介：1．联系生活实例，认识杠杆是一根在力的作用下，可绕固定点转动的硬棒，能从常见的工具中辨识出杠杆．

简介：

简介：Ｏｎ　△Ｉ＝４　Ｂｉｆｕｒｃａｔｉｏｎ　ＰｈｅｎｏｍｅｎａＯｎ△Ｉ＝４ＢｉｆｕｒｃａｔｉｏｎＰｈｅｎｏｍｅｎａ￥ＺｈａｎｇＪｉｎｇｙｅ；ＹａｎｇＳｕｎａｎｄＭｉｋｅＧｕｉｄｒｙＴｈｅｅｘｐｅｒｉｍｅｎｔｓ－ｂｙｔｈｅｎｅｗ７－－ｒａｙｄｅｔｅｃｔｏｒ...

简介：

简介：1．运用实例分析，认识运动的物体能够做功，所具有的能量称为动能．2．通过探究实验，知道动能的大小与物体的质量和运动速度有关．能运用动能与质量、速度的关系解释简单的生活现象．

简介：Carbonnanotubeswithjunctionsmayplayanimportantroleinfuturenanoelectronicsandfuturenanodevices.Inparticular,junctionsconstructedwithmetalandsemiconductingnanotubeshavepotentialapplications.Basedontheorthogonaltight-bindingmoleculardynamicsmethod,wepresentourstudyofthestructurestabilityofI-typecarbonnanotubejunctions.

简介：ThenewKEKCentralcomputersystememployedHPSSfordatamanagementTogainhighperformanceaccesstoHPSSeasily,webuiltawrapperoftheclientAPL.

简介：充分一致的相对论的连续统随机阶段近似(RCRPA)以格林的功能技术被构造。在到原子刺激的连续统光谱的贡献完全被单个粒子对待的这个方法，格林是功能，它也在迪拉克海包括否定状态在没有海近似。RCRPA和数字细节的理论形式主义被介绍。单个粒子格林的功能被迪拉克方程的常规、不规则的答案的一个合适的产品数字地计算。数字细节和在动量表示的RCRPA的形式主义被介绍。

简介：TheLaboratoryforIntenseLasers（L2I）isaresearchcentreinopticsandlasersdedicatedtoexperimentalresearchinhighintensitylaserscienceandtechnologyandlaserplasmainteraction.Currentlythelaboratoryisundergoinganupgradewiththegoalofincreasingtheversatilityofthelasersystemsavailabletotheusers,aswellasincreasingthepulserepetitionrate.Inthispaperwereviewthecurrentstatusofthelaserresearchanddevelopmentprogrammeofthisfacility,namelytheupgradedcapabilityandtherecentprogresstowardstheinstallationofanultrashort,diode-pumpedOPCPAlasersystem.

简介：

简介：

简介：Bianchi类型--我有通过这些技术的磁场ofbarotropic完成式液体分发的宇宙论的模型使用了由的巨大的绳更最近并且Stachel被调查。获得宇宙的确定的模型，宇宙充满barotropic完成式液体分发，这被假定。磁场由于与无限的电的电导率沿着X轴生产的电流。模型的行为当面并且和另外的物理方面的磁场的缺席进一步被讨论。

简介：在数字方法的帮助下，在旋转的洞以内的流动地和它的伴随的损失机制在1二的st部分分开纸。便于比较，旋转洞进一步作为转子定子洞案例和转子转子洞被分类大小写。除了流动近围之外，结果作为inviscid流动在两种洞行为以内显示那流动，附近更低的G区域并且在旋转的孔的附近。在除了如此的inviscid-flow-dominate领域的区域，理论核心旋转因素能安全地被用来在洞以内预言swirl比率。当详细流动模式被考虑时，Ekman类型流动在在哪儿的表面边界层的圆周附近存在粘滞效果是非可以忽略的。由于模仿的洞案例的复杂侧面，然而，旋涡结构在洞以内被改变。由比较，打漩比率能被用来预言损失的大小。由于转子转子洞的相对明显的旋转效果，打漩比率甚至在当前的模型增加到1.4，它比包围圆盘快意味着那流动是动人的。进一步的调查发现这种高度旋转的流动伴有严肃的不受欢迎的压力损失。不同于它的对应物，插句地打漩当液体通过转子定子洞时，超过1.0的比率不发生。如此的结构设计什么时候是不可避免的，因此被建议有附加里面的throughflow的转子转子流动洞应该在引擎设计被避免或某些大小应该被提供。自从这些维的参数在state-of-art的设计是典型的，在当前的纸做的模拟是有意义的。Re和Cw的相对更低的范围没在二部分糊的水流被考虑。

简介：Accordingtothegoodchargetransportingpropertyofperovskite,wedesignandsimulateap–i–n-typeall-perovskitesolarcellbyusingone-dimensionaldevicesimulator.Theperovskitechargetransportinglayersandtheperovskiteabsorberconstitutetheall-perovskitecell.Bymodulatingthecellparameters,suchaslayerthicknessvalues,dopingconcentrationsandenergybandsofn-,i-,andp-typeperovskitelayers,theall-perovskitesolarcellobtainsahighpowerconversionefficiencyof25.84%.Thebandmatchedcellshowsappreciablyimprovedperformancewithwidenabsorptionspectrumandloweredrecombinationrate,soweobtainahighJ_(sc)of32.47mA/cm~2.Thesmallseriesresistanceoftheall-perovskitesolarcellalsobenefitsthehighJ_(sc).Thesimulationprovidesanovelthoughtofdesigningperovskitesolarcellswithsimpleproducingprocess,lowproductioncostandhighefficientstructuretosolvetheenergyproblem.

简介：介绍了阻变存储器及其I-V特性的测试分析方法。通过测量三明治结构的阻变存储器的I-V特性,采用多种拟合方法,与导电机制原理对比,可以判断器件的导电机制,便于深入分析阻变机理。

简介：AseriesofRbxCs1-xAg4I5(x=0-1)thinfilmsweregrownbyvacuumevaporationonNaCIcrystalsubstratesat350K.Theabsorptionspectraofthesefilmsweremeasuredat80Kinthewavelengthrangefrom240nmto400nm.ItisshownthatsuperionicconductorthinfilmsofquaternarycompoundRb0.5Cs0.5Ag4I5andternarycompoundRbAg415canbeobtainedatx=0.5-0.6andx=0.7-1,respectively.Atx=0.65,thecombinedcompoundfilmofthemixtureof30mol%RbAg4I5and70mol%Rb0.5Cs0.5Ag4I5ispresented.Then,basedonthespectralpositionsoftheA1andA2peaks,wedeterminedthattheRb0.5Cs0.5Ag4I5excitoncouplingenergyRexis0.21eV,theforbiddenzonewidthEgis3.82eVandtheexcitonradiusaexis0.70hm.Furthermore,theionicconductivitiesofsuperionicconductorthinfilmsofRbAg4I5andRb0.5Cs0.5Ag4I5andtheirmixturefilmareinvestigated,respectively,inthetemperaturerange303K-393K.

简介：Inthispaper,normalincidenceverticalp-i-nphotodetectorsonagermanium-on-insulator(GOI)platformweredemonstrated.Theverticalp-i-nstructurewasrealizedbyion-implantingboronandarsenicatthebottomandtopoftheGelayer,respectively,duringtheGOIfabrication.Abruptdopingprofileswereverifiedinthetransferredhigh-qualityGelayer.Thephotodetectorsexhibitadarkcurrentdensityof~47mA∕cm~2at-1Vandanopticalresponsivityof0.39A/Wat1550nm,whichareimprovedcomparedwithstate-of-the-artdemonstratedGOIphotodetectors.Aninternalquantumefficiencyof~97%indicatesexcellentcarriercollectionefficiencyofthedevice.Thephotodetectorswithmesadiameterof60μmexhibita3dBbandwidthof~1GHz,whichagreeswellwiththeoreticalcalculations.Thebandwidthisexpectedtoimproveto~32GHzwithmesadiameterof10μm.ThisworkcouldbesimilarlyextendedtoGOIplatformswithotherintermediatelayersandpotentiallyenrichthefunctionaldiversityofGOIfornear-infraredsensingandcommunicationintegratedwithGeCMOSandmid-infraredphotonics.

简介：通过理论分析和PIC数值模拟,研究了阳极腔区结构对无箔二极管I-Ⅴ特性的影响,得到了束流强度和结构影响因子的变化规律.研究发现,当阴阳极间距大于0时,无箔二极管的结构影响因子随着阳极腔区半径的增大而减小并逐渐趋于稳定,且对于较小的阴极外半径、较大的漂移管半径、较大的阴阳极间距,达到稳定后的结构影响因子越小,并给出了结构影响因子的可调节范围.在TPG700脉冲驱动源上开展了初步实验研究,对实验中的回流电子束进行数值模拟分析并去除其影响以后,实验结果很好地符合了理论分析结论.

简介：Photonics-basedradarwithaphotonicde-chirpreceiverhastheadvantagesofbroadbandoperationandreal-timesignalprocessing,butitsuffersfrominterferencefromimagefrequenciesandotherundesiredfrequency-mixingcomponents,duetosingle-channelreal-valuedphotonicfrequencymixing.Inthispaper,weproposeaphotonicsbasedradarwithaphotonicfrequency-doublingtransmitterandabalancedin-phaseandquadrature(I/Q)de-chirpreceiver.Thisradartransmitsbroadbandlinearlyfrequency-modulatedsignalsgeneratedbyphotonicfrequencydoublingandperformsI/Qde-chirpingoftheradarechoesbasedonabalancedphotonicI/Qfrequencymixer,whichisrealizedbyapplyinga90°opticalhybridfollowedbybalancedphotodetectors.Theproposedradarhasahighrangeresolutionbecauseofthelargeoperationbandwidthandachievesinterference-freedetectionbysuppressingtheimagefrequenciesandotherundesiredfrequency-mixingcomponents.Intheexperiment,aphotonics-basedK-bandradarwithabandwidthof8GHzisdemonstrated.ThebalancedI/Qde-chirpingreceiverachievesanimage-rejectionratioofover30dBandsuccessfullyeliminatestheinterferenceduetothebasebandenvelopeandthefrequencymixingbetweenradarechoesofdifferenttargets.Inaddition,thedesireddechirpedsignalpowerisalsoenhancedwithbalanceddetection.Basedontheestablishedphotonics-basedradar,inversesyntheticapertureradarimagingisalsoimplemented,throughwhichtheadvantagesoftheproposedradarareverified.

简介：Amechanismisproposedfornucleatepoolboilingheattransferalongwithageneralmodelforbothpureliquidsandbinarymixtrues.Acombinedphysicalmodelofbubblegrowthisalsoproposedalongwithacorrespondingbubblegrowthmodelforpureliquidsonsmoothtubes.Usingthegeneralmodelandthebubblegrowthmodelforpureliquids,ananalyticaslmodelfornucleatepoolboilingheattransferofpureliquidsonsmoothtubesisdeveloped.