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306 个结果
  • 简介:Thebilinearformofthe(2+1)-dimensionalnon-isospectralAKNSsystemisderived.ItsN-solitonsolutionsareobtainedbyusingtheHirotamethod.Asareduction,a(2+1)-dimensionalnon-isospectralSchrdingerequationanditsN-solitonsolutionsareconstructed.

  • 标签: 孤立子解 Hirota法 等光谱 SCHRODINGER方程
  • 简介:Inthecontemporarylargetokamak,thedisruptiveterminationofadischargewillreducethelifetimeofthefirstwallmaterialswiththeintenseheatfluxattheenergyquenchandtheintenserunawayelectronsduringthecurrentquench,andgeneratehighelectronmagneticforcesonvacuumvesselcomponentswithintenseeddycurrentatthecurrentquench.Thus,avoidanceandsofteningoftheenergyquenchandthecurrentquenchandcontrollinganexpecteddisruptionoremergencyshutdownmustbeestablishedinthepresenttokamakmachines.

  • 标签: 高Z杂质 HL-1M 激光吹气 等离子体 破裂放电 安全终止
  • 简介:寻求新无限的顺序象soliton一样非线性的进化方程的准确答案(旧姓)由在辅助方程方法上开发建设和机械化的二个特征,秒椭圆形的方程高度被学习并且新类型答案和B?cklund转变被获得。(2+1)然后,维的碎soliton方程作为一个例子和它的无限的顺序被选象soliton一样准确解决方案在符号的计算系统Mathematica的帮助下被构造,它包括无限的顺序Jacobi椭圆形的类型的光滑的象soliton一样解决方案,Jacobi椭圆形的类型的无限的顺序协议soliton解决方案和指数的函数类型和三角形的功能的无限的顺序山峰soliton解决方案打字。

  • 标签: 破裂孤子方程 无限序列 精确解 Mathematica BACKLUND变换 Jacobi
  • 简介:用特殊Painleve-Baecklund转变以及扩大印射的途径和线性重叠定理,我们获得的可变分离答案的新家庭(2+1)维的概括Broer-Kaup(GBK)系统。基于导出的准确答案,我们揭示局部性的刺激的一些新奇进化行为,即分裂和熔化现象在(2+1)维的GBK系统。

  • 标签: GBK系统 变量分离解 局部激发 裂变 聚变
  • 简介:Extractionofthein-mediumpropertiesofstrangeparticlesfromheavy-ioncollisionsisverycomplicated,sincehenucleardensityvariesintheevolutionofnucleus-nucleuscollisions.Toavoidtheuncertaintiesofthebaryonensitiesduringthestageofstrangeparticleproduction,onecaninvestigateproton-nucleuscollisionswheretheucleardensityisdefinitearoundthesaturationdensity.DynamicsofstrangeparticlesproducedintheprotoninduceduclearthereactionsnearthethresholdenergieshasbeeninvestigatedwithintheLanzhouquantumoleculardynamics(LQMD)transportmodel.Thein-mediummodificationsonparticleproductionindensenuclearmatterareconsideredthroughthecorrectionstotheelementarycrosssectionsviatheeffectivemassandhemean-fieldpotentials[1].

  • 标签: STRANGE PARTICLES In-medium
  • 简介:Parametersforthe3W1sourceatBSRFweredeterminedinboththededicatedandparasiticmodeandtheirsuitabilityforproteincrystallographybeamlineatBSRFwererealized.Itisdiscussedthatthephysicsmotivationandthedesignofthe3W1iscomparedwithsimilarexperimentalstationsattheBrazilianLightSourec(1.37Gev)andMax-IIinSweden(1.5GeV).Thephotonfluxfromthe3W1sourcdisabout2×10^11photon/smAinthewavelengthrangeof2.0-0.9Ainparasiticmodeand50-80timeshigherinthededicatedmode.Boththededicatedandparasiticmodesaresuitableformacromolecularstructureexperiments.2001ElsevierScienceB.V.Allrightsreserved.

  • 标签: BSRF 北京同步辐射装置 蛋白质 生物化学 结构分析 结晶学
  • 简介:Thermodynamicpropertiesandphasediagramsofamixedspin-(1,2)Isingferrimagneticsystemwithsingleionanisotropyonhexagonalnanowirearestudiedbyusingeffective-fieldtheorywithcorrelations.Thesusceptibility,internalenergyandspecificheatofthesystemarenumericallyexaminedandsomeinterestingphenomenainthesequantitiesarefound.TheeffectoftheHamiltonianparametersonphasediagramsareexaminedindetail.Besidessecond-orderphasetransition,linesoffirst-ordertransitionandtricriticalpointsarefound.Inparticular,wefoundthatforsomenegativevaluesofsingle-ionanisotropies,thereexistfirst-orderphasetransitions.

  • 标签: HEXAGONAL ISING NANOWIRE mixed spin-(1 2)
  • 简介:Usingasimpletwo-parameterwavefunction,wecalculatevariationallythebindingenergyofpositivelyandnegativelychargedexcitonsinGaAs/AlxGa1-xAsquantumwellsforwellwidthsfrom10to300A.Weconsidertheeffectofeffectivemass,dielectricconstantmismatchinthetwomaterials,andthewholecorrelationamongtheparticles.Theresultsarediscussedandcomparedindetailwithpreviousexperimentalandtheoreticalresults,whichshowfairagreementwiththem.

  • 标签: 量子力学 带电激子 GAAS/ALXGA1-XAS 最子阱
  • 简介:Ageneralmappingdeformationmethodispresentedandappliedtoa(2+1)-dimensionalBoussinesqsystem.Manynewtypesofexplicitandexacttravellingwavesolutions,whichcontainsolitarywavesolutions,periodicwavesolutions,JacobianandWeierstrassdoublyperiodicwavesolutions,andotherexactexcitationslikepolynomialsolutions,exponentialsolutions,andrationalsolutions,etc.,areobtainedbyasimplealgebraictransformationrelationbetweenthe(2+1)-dimensionalBoussinesqequationandageneralizedcubicnonlinearKlein-Gordonequation.

  • 标签: 三维Boussinesq方程 行波解 广义图分形理论 周期波解 孤波解 数学物理方法
  • 简介:针对红外探测器在空间应用中受高能粒子辐照后性能衰退的问题,利用电子束辐照实验,开展了位移损伤对HgCdTe材料红外透射光谱影响的研究.通过对比辐照前后材料的性能变化,结合光在材料中的传播过程及半导体辐射效应理论,分析了位移损伤对HgCdTe材料红外透射光谱的影响机制.结果表明:HgCdTe材料经电子辐照后,红外透射光谱发生衰退,衰退的幅度随辐照注量的增大而增大,且短波方向上的衰退幅度大于长波方向上的衰退幅度.该工作可为深入开展HgCdTe红外探测器辐射损伤效应及损伤机理的研究提供参考.

  • 标签: HGCDTE材料 红外透射光谱 电子辐照 位移损伤
  • 简介:Veryrecently,BelleannouncedtheirobservationofΥ(5S)!bJ!(J=0;1;2),indicatingthattheΥ(5S)!bJ!decaysalsohavelargedecaywidths,i.e.,themeasuredbranchratiosofΥ(5S)!bJ!are<3:410??3,(1:640:23+0:30??0:22)10??3,and(0:570:220:07)10??3withJ=0;1;2,respectively[1].ItshouldbenoticedthateventhoughthetreelevelcontributionstoΥ(5S)!bJ!(J=0;1;2)shouldbestronglysuppressedduetotheOkubo-Zweig-Iizuka(OZI)rule,suchlargedecaywidthsareobserved,whichagaininspiresourinterestinunderstandingsuchquantities.Inthiswork,weproposethatthecontributionfromthehadronicloopshouldbeconsideredinstudyingΥ(5S)!bJ!.

  • 标签: LOOP LOOP BE OUR IT
  • 简介:RecentexperimentalresultsofHL-1MtokamakandprogressofHL-2Aprojectarepresented.Strongfishboneinstabilitywasobservedduringoff-axisECRH.ThisisfirstobservationofthefishboneinstabilitypurelydrivenbyenergeticelectronsproducedbyECRH.TheMBIwasfirstproposedanddemonstratedonHL-1M.RecentlynewresultsofMBIexperimentwereobtainedbyincreasingthepressureofgas.Astair-shapedensityincrementwasobtainedwithhigh-pressuremulti-pulseMBIjustlikethedensityevolutionbehaviorduringthemultipelletinjection.Itisshown

  • 标签: HL-1M HL-2A 实验数据 托卡马克装置 等离子体物理学
  • 简介:YbxY1-xAl3(BO3)4(x=0.1,0.07and0)crystalshavebeengrownbythefluxmethod.ThegrowthdefectsofYbxY1-xAl3(BO3)4crystalsweredetectedbyX-raytopography.ItisfoundthattheperfcetionofYbYABcrystalwithlowYbdopantisbetterthanthatwithhighYbdopant.InYb0.1Y0.9Al3(BO3)4crystal,growhtbands,growthboundaries,grown-indislocationsandinclusionswereobserved.Howver,thedensitiesofgrowthdefectsforYb0.07Y0.93Al3(BO3)4andYAl3(BO3)4arelowandnoobviousinclusionsareobservedinthesecrytals.Inaddition,growthtwinswrerdetectedinYbxY1-xAl3(BO3)4crystalbyusingthechemicaletchingmethod.ItisfoundthatthegrowthtwinsoccurfrequentlyinYb0.01Y0.9Al3(BO3)4crystalwhereasnogrowthtwinappearsinYAl3(BO3)4crystal.Basedontheexperimentalobservations,theformationmechanismofgrowthtwinsisdiscussed.Inthemeantime,theeffectivemeasuresforreducingthegrowthtwinsanddefectsareproposed.2001ElsevierScienceB.V.Allrightsreserved.

  • 标签: YbxY1-xAl3(BO3)4晶体 晶体生长 结构缺陷 硼酸盐晶体 形貌学 X射线
  • 简介:利用热力学原理,导出了一共晶二元系热力学量的计算方法,并以Cd_T系为例计算了相应的活度系数,计算结果与文献报道相符。

  • 标签: 共晶二元系 热力学量 活度
  • 简介:随着科技的发展,对测量微小物体尺寸的精确度、速度都提出了新的要求,作者曾提出过一基于激光发射测量微小物体尺寸的技术(见文献1)。该技术原理简单,测量微小物体尺寸的误差可控。然而,该技术在测量物体的大小方面还存在着一定的局限性;同时为了使系统达到最大测量范围,小齿的斜面与底板夹角a在实际过程中需要讨论。本研究对实验装置进行适当改进,从而解决了上述瓶颈问题。

  • 标签: 激光反射 微小距离测定
  • 简介:测定了在高压条件下两金属(钙和锌)的8-羟基喹啉络合物的晶体粉末样品的发光行为和原位X光衍射光谱.结果表明,压力对其发光性质产生极大的影响.随着压力的增加,8—羟基喹啉钙的发光强度在3GPa以内时大大增加,随后发光强度快速下降.到7GPa左右时几乎为零,而8-羟基喹啉锌的发光强度随压力的增加而逐渐降低,到7GPa左右时约为常压的10%。高压下的原位X光衍射结果表明,8—羟基喹啉锌的晶体在3—4GPa开始发生非化相变,在7GPa时该非晶化相变完成,样品的x光衍射完全消失.而8—羟基喹啉锌在压力的作用下(至16GPa)没有发生明显的相变。

  • 标签: 高压 金属8-羟基喹啉络合物 发光性质 晶体结构
  • 简介:基于电偶极子场强的矢量表达式,应用坐标系转换关系,推导出斜置电偶极子场强在笛卡尔坐标系、球面坐标系和柱面坐标系中的具体表达式。

  • 标签: 电偶极子 场强 欧拉 罗德里格参数