学科分类
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16 个结果
  • 简介:导致激光的血浆今天代表普遍分光镜的排放来源。它能容易用紧缩、可靠的毫微秒被产生材料的一个大变化上的搏动的激光。它为例如有导致激光的故障光谱学(解放)的spectrochemical分析的申请变得那么流行一个人趋于忘记导致它的产生并且管理它的进化的复杂物理、化学的过程。这篇评论文章的目的是总结必要的背景从它的产生理解并且描述导致激光的血浆到它的扩大进周围的气体。目的是不详细说明每个过程的细节;在文学为那有众多的专业化论文和书。这里的目标是在必要理解元素需要从一个复杂过程把导致激光的血浆描述为结果的一份一样的报纸聚在一起。这些元素能在背景气体在象激光事相互作用,材料的激光脱离,热、电离的气体的光、热力学的性质,或血浆繁殖那样的几块相关却独立的地里被驱散。我们相信那介绍以一条全面的路并且在这份报纸的有限的页理解导致激光的血浆的元素的整体将对进一步的开发有用并且优化LIBS技术的使用。每次如此的说明变得可能、有用,在我们的实验室获得的试验性的结果被用来说明学习物理过程。

  • 标签: 激光诱导等离子体 等离子体光谱 发射源 纳秒脉冲激光 光谱化学分析 物理过程
  • 简介:Airfoilself-noiseisacommonphenomenonformanyengineeringapplications.Aimingtostudytheunderlyingmechanismofairfoilself-noiseatlowMachnumberandmoderateReynoldsnumberflow,anumericalinvestigationispresentedonnoisegenerationbyflowpastNACA0018airfoil.Basedonahigh-orderaccuratenumericalmethod,boththenear-fieldhydrodynamicsandthefar-fieldacousticsarecomputedsimultaneouslybyperformingdirectnumericalsimulation.Themeanflowpropertiesagreewellwiththeexperimentalmeasurements.Thecharacteristicsofaerodynamicnoiseareinvestigatedatvariousanglesofattack.Theobtainedresultsshowthatincliningtheairfoilcouldenlargeturbulentintensityandproducelargerscaleofvortices.Thesoundradiationismainlytowardstheupperandlowerdirectionsoftheairfoilsurface.Athigherangleofattack,thetonalnoisetendstodisappearandthenoisespectrumdisplaysbroad-bandfeatures.

  • 标签: 直接数值模拟 自噪声 翼型 数值计算方法 计算流体力学 实验测量
  • 简介:MassselectionforfastgrowthwasconductedinthreePacificoyster(Crassostreagigas)stocksfromChina,JapanandKoreausingpreviouslyestablishedlines(CS1,JS1,andKS1).Todeterminewhethercontinuousprogresscanbeachievedbyselectionforgrowth,theprogenyofthreesecond-generationPacificoysterlineswasselectedforshellheightandevaluatedviaa400-dayfarmingexperiment.Whenharvestedattheendoftheexperiment,theselectedcrossesofCS2,JS2,andKS2linesgrewby9.2%,10.2%and9.6%largerthanthecontrolcrosses,respectively.Duringgrow-outstage,thegeneticgainofthreeselectedlineswas(10.2±1.4)%,(10.4±0.3)%,and(8.4±1.6)%,respectively;andthecorrespondingrealizedheritabilitywas0.457±0.143,0.312±0.071and0.332±0.009,respectively.Theseresultsindicatedthattheselectionforfastgrowthachievedsteadyprogressinthesecondgenerationofoyster.OurworkprovidessupportiveevidenceforthecontinuityofthePacificoysterselectivebreedingprogram.

  • 标签: 太平洋牡蛎 第二代 质量选择 同比增长 遗传增益 育种计划
  • 简介:生来的杀手(NK)房间是天生的免疫系统的部分并且由于他们没有优先的促进感受性,杀死感染的房间或癌症房间的能力是为免疫疗法的一种诱惑选择。在整个过去的20年,不同的组能在vitro复制NK房间开发,并且NK房间个体发生学习提供了基础让协议的建立为免疫疗法在vitro生产NK房间。这里,我们简短讨论NK房间开发和NK房间免疫疗法途径。我们考察为在vitro的房间区别,干细胞采购被使用的、出版协议,质问的NK需要的因素,为好生产的未来方向练习协议。

  • 标签: 造血干细胞 免疫治疗 体外分化 自然 NK细胞 细胞发育
  • 简介:Identifyingeachprocessandtheirconstraintrelationsfromthecomplexwiringharnessdrawingsquicklyandaccuratelyisthebasisforformulatingprocessroutes.Accordingtotheknowledgeofautomotivewiringharnessandthecharacteristicsofwiringharnesscomponents,weestablishedthemodelofwiringharnessgraph.Thenweresearchthealgorithmofidentifyingtechnologyprocessesautomatically,finallywedescribetherelationshipsbetweenprocessesbyintroducingtheconstraintmatrix,whichisinordertolayagoodfoundationforharnessprocessplanningandproductionscheduling.

  • 标签: 汽车线束 技术工艺 自动生成 算法 进程 自动识别技术
  • 简介:Wedemonstrateexperimentallyaradiofrequencyarbitrarywaveformgeneratorusingtheincoherentwavelengthto-timemappingtechnique.Thesystemisimplementedbyamplitudemodulationofabroadbandopticalresourcewhosespectrumisreshapedbyaprogrammableopticalpulseshaperandtransmittedoverasinglemodefiberlink.Theshapeofthegeneratedwaveformiscontrolledbytheopticalpulseshaper,andthefiberlinkintroducesacertaingroupvelocitydelaytoimplementwavelength-to-timemapping.Assistedbytheflexibleopticalpulseshaper,weobtaindifferentshapesofopticalwaveforms,suchasrectangle,triangle,andsawtoothwaveforms.Furthermore,wealsodemonstrateultra-widebandgeneration,suchasGaussianmonocycle,doublet,andtripletwaveforms,usingtheincoherenttechnique.

  • 标签: 任意波形发生器 时间映射 非相干 波长 光子产生 脉冲整形器
  • 简介:用向量衍射理论和现象学的模型,这份报纸调查集中的油炸圈饼横梁(DB)与不同拓扑的费用激动的单个中心对称的nanosphere的第二泛音代(SHG)。当粒子旁边是激动的时,强壮的向后的SHG(BSHG)出现的结果表演与拓扑的费用集中了DB????????????????£吗?

  • 标签: 二次谐波产生 中心对称 纳米球 兴奋 圈梁 密集
  • 简介:Atotal61cloneparentsand320open-pollinationprogeniesfrom8cloneindividualswereidentifiedby12polymorphicSSRloci.Theresultshowedthatthelevelofgeneticdiversityinprogenypopulationwasthesameasinmaternalpopulation,progenypopulationhadallallelesdetectedinmaternalpopulation,andtherewerenotobvioussurplusphenomenonofhomozygotesinprogenypopulation(F=0.046).Thesouthcrownhadmorestrobilithanthenorthcrown,howeverthegeneticdiversityofthenorthcrownstrobiliwasnotsubstantiallyreduced.Theprogenyofneutraltreeshadthesamelevelofgeneticdiversityasintheprogenyofpartialfemaletrees,withthefixationindextendedtobezero,whichwasaccordedwithHardy-Weinbergequilibrium.Themultilocusoutcrossingrateintheseedorchardwas1.097,andtherewasnosignificantinbreedingbetweenparents(t_m-t_s=-0.031).Themultilocusoutcrossingrateandsinglelocusoutcrossingrateinthesouthcrownwerehigherthanthatinthenorthcrown.Themultilocusoutcrossingrateofpartialfemaletreeswasthesameasinneutraltrees,andtheneutraltreehadnoobviousdecliningoutcrossingratewithreducedproportionoffemaleandmalestrobiluscomparedwithpartialfemaletree,withthefixationindextendedtobezero.Theprogenyofthesecondgenerationclonalseedorchardstillhadrichgeneticdiversity,geneexchangeamongcloneswasrelativelysufficient,andbiparentalinbreedingwasnotsignificant.

  • 标签: PINUS massoniana second generation seed ORCHARD
  • 简介:Atwo-dimensional(2D)numericalmodelisdevelopedforthewavesimulationandpropagationinawaveflume.Thefluidflowisassumedtobeviscousandincompressible,andtheNavier-Stokesandcontinuityequationsareusedasthegoverningequations.Thestandardk-εmodelisusedtomodeltheturbulentflow.TheNavierStokesequationsarediscretizedusingthestaggeredgridfinitedifferencemethodandsolvedbythesimplifiedmarkerandcell(SMAC)method.Wavesaregeneratedandpropagatedusingapistontypewavemaker.Anopenboundaryconditionisusedattheendofthenumericalflume.Somestandardtests,suchasthelid-drivencavity,theconstantunidirectionalvelocityfield,theshearingflow,andthedam-breakonthedrybed,areperformedtovalidthemodel.Todemonstratethecapabilityandaccuracyofthepresentmethod,theresultsofgeneratedwavesarecomparedwithavailablewavetheories.Finally,theclusteringtechnique(CT)isusedforthemeshgeneration,andthebestconditionissuggested.

  • 标签: 数值波浪水槽 Navier-Stokes方程 非线性波 流体体积法 集群技术 有限差分方法
  • 简介:我们试验性地在figure-of-eight表明混乱产生有一枚光纤维戒指(OFR)的做耳的纤维激光(F8L)。与极化控制器的适当联合,我们发现到混乱的纤维激光展览perioddoubling线路,和混乱自我同步的动力学有一个趋势显著地被减少。试验性的结果证明趋势与干扰和在光纤维戒指的光的非线性的阶段移动有关。同时,混乱动力学与极化状态和泵力量有关。

  • 标签: 掺铒光纤激光器 混沌自同步 光纤环 偏振控制器 非线性相移 混沌动力学
  • 简介:精力层次,波浪功能和秒顺序非线性的危险性被基于寓言、非寓言的乐队使用一个不对称的模型在GaAs/Al0.2Ga0.8As/Al0.5Ga0.5As不对称的量井(AQW)计算。当在更宽的井在狭窄的量井并且在更高的躺subband边分析现象时,non-parabolicity的影响不能被忽视。在两倍回声(医生)下面调节的数字结果表演,secondorder差别频率产生(DFG)和光校正(或)分别地,在AQW的产生危险性到达2.5019m/V和13.208m/V它比体积GaAs的那些大得多。而且,我们计算AQW的吸收系数并且发现二泵波长对应于最大的吸收,因此适当的泵横梁必须被选择产生兆兆赫(THz)由DFG的放射。

  • 标签: 非对称量子阱 THZ波 砷化铝镓 差频 计算结果 泵浦波长