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71 个结果
  • 简介:一个不安方法为解决非线性的Korteweg-deVries(KdV)在动态系统的上下文被介绍方程。最好的效率为很少perturbative修正被获得。它被看那,这条途径的集中的问题完全这里被保证,因为在系列包括的一小部分术语能描述一个足够的准确答案。有quintic花键的答案的比较,;有限差别被介绍。

  • 标签: 扰动 泰勒级数 五次样条 KORTEWEG-DE VRIES方程
  • 简介:Thequicklyincreasingdatatransferloadrequiresanurgentrevolutionincurrentopticalcommunication.Orbitalangularmomentum(OAM)multiplexingisapotentialcandidatewithitsabilitytoconsiderablyenhancethecapacityofcommunication.However,thelackofacompact,efficient,andintegratedOAM(de)multiplexerpre-ventsitfrombeingwidelyapplied.Byattachingvortexgratingsontothefacetsofafew-modefiber,wedem-onstrateanintegratedfiber-basedOAM(de)multiplexer.AvortexgratingfabricatedonthefiberfacetenablesthedirectmultiplexingofOAMstatesatoneportandthedemultiplexingofOAMstatesattheotherport.Themeasuredbiterrorrateofthecarriersignalafterpropagatingthrougha5-kmfew-modefiberconfirmsthevalidityandeffectivenessoftheproposedapproach.Theschemeoffersadvantagesinfuturehigh-capacityOAMcom-municationbasedonopticalfiber.

  • 标签: 通信技术 通信能力 发展现状 光纤传输
  • 简介:在ultracold温度的原子Bose爱因斯坦冷凝作用的试验性的实现在创造并且操作冷分子导致了快速的进展,并且它生产了量事波浪superchemistry的一个新研究领域。与古典Arrhenius法律相反,通道主导的ultracold反应能通过高度控制的磁电机光的技术被认识到。新奇的量效果在这些冷反应被识别了,例如在分裂的超级选择的规则由三个原子而成的分子,和量尺寸(容器形状)效果。在这评论,我们在这个迷人的事波浪仙境集中于许多新成就,包括在装配冷分子,在触发集体抽象反应的量噪音,和磁性的阶段的有限数字的效果和双裂缝干扰在催化激光的量转移的量混合纺纱的气体。事波浪superchemistry的实际应用也被介绍,例如经由量相片协会,和旋量或甚至chiral分子的提高激光的创造的光信息存储。

  • 标签: 物理学 理论 现状 发展
  • 简介:在这篇论文,含蓄的对称限制被计算并且它宽松的对和伴随的联系二进制nonlinearization宽松的对为修改Korteweg-deVries(mKdV)方程被执行。在介绍二个新自变量,自变数以后,我们发现在含蓄的对称限制下面,空间部分和mKdV方程的时间的部分被分解成二个有限维的系统。而且,我们证明获得的有限维的系统是Hamiltonian系统并且完全在Liouville意义的integrable。

  • 标签: 绝对对称 约束条件 可积分 哈密顿系统 MKDV方程
  • 简介:从一个五维的Minkowski看法,搬到de保姆空间时间的一个免费spin-0粒子的五维的尖动量是保守人士,它象geodesics一样的时间能被完全并且特别地标记。基于那观察并且在在de保姆空间时间,Beltrami-de保姆KleinGordon方程的答案和他们的asymptotic行为并列的Beltrami工作被给。

  • 标签: 类时 测地线 时间 量子运动
  • 简介:Wehavedesignedandrealizedanathermal4-channelwavelength(de-)multiplexerinsiliconnitride(SIN).Minimizedthermalsensitivityisachievedinawidewavelengthrangebyusingwideandnarrowwaveguideswithlowanddifferentthermal-opticcoefficientsinthetwoarmsofMach-Zehnderinterferometers(MZIs).TheSiNcorelayerandSiO2claddinglayersaredepositedbyalow-temperatureplasma-enhancedchemicalvapordep-ositionprocess.ThefabricatedMZIfilterexhibitsathermalsensitivitywithin4-2.0pm/℃inawavelengthrangeof55nmtonear1300nm.Then,anathermal(de-)multiplexerbasedoncascadedMZIshasbeendemonstratedwithacrosstalk〈-22dBandathermalsensitivity〈4.8pm/℃forallfourchannels,reducedby77%comparedtoaconventionalSiN(de-)multiplexer.OwingtothepassiveoperationandcompatibilitywiththeCMOSback-endprocess,ourdeviceshavepotentialapplicationsin3Dintegrationofphotonicsandelectronics.

  • 标签: 氮化硅 通信技术 发展现状 材料学
  • 简介:Recently,therehasbeenmuchattentiondevotedtoresolvingthequantumcorrectionstotheBekenstein-Hawkingblackholeentropy.Inparticular,manyresearchershaveexpressedavestedinterestinthecoefficientofthelogarithmictermoftheblackholeentropycorrectionterm.Inthispaper,wecalculatethecorrectionvalueoftheblackholeentropybyutilizingthegeneralizeduncertaintyprincipleandobtainthecorrectiontermcaused,bythegeneralizeduncertaintyprinciple.BecauseinourcalculationwethinkthattheBekenstein-Hawkingareatheoremisstillvalidafterconsideringthegeneralizeduncertaintyprinciple,wederivethatthecoefficientofthelogarithmictermoftheblackholeentropycorrectiontermispositive.Thisresultisdifferentfromtheknownresultatpresent.Ourmethodisvalidnotonlyforfour-dimensionalspacetimesbutalsoforhigher-dimensionalspacetimes.Inthewholeprocess,thephysicsideaisclearandcalculationissimple.Itoffersanewwayforstudyingtheentropycorrectionofthecomplicatedspacetime.

  • 标签: 广义不确定性原理 黑洞熵 区域理论 多维空间
  • 简介:在1935,迪拉克证实在de保姆空格而是两个精力动量操作员也不他们的保守法律的物理波浪方程被给。在它在在那里的de保姆组被证明那的这篇文章是对海森堡组和组们是的这的生成器同形的一个亚群组遵守一条保守法律的精力动量操作符。

  • 标签: HEISENBERG群 能量要素 Einstein相对论 能量守恒 de-Sitter空间
  • 简介:Thisisafollowofpreviousworkentitled"OneElectronAtominSpecialRelativitywithdeSitterSpaceTimeSymmetry"[Commun.Theor.Phys.57(2012)930].Inthispaper,weconsiderthehigherordercalculationsandcontributionsinthepreviousframeworktosolveoneelectronatomsindeSitterinvariantrelativisticquantummechanics.Thenext-to-leading-ordercalculationsin1/R2-expansionsshowthatthefine-structureconstantαisvariantwithcosmologictimegoingbyinthedeSitterinvariantspecialrelativisticquantummechanicswithstandardFRWcosmologicmodel.

  • 标签: hydrogen ATOM special RELATIVITY with de
  • 简介:TheEinstein'sgeneralrelativityisformulatedintheHamiltonianformforaspatiallyflat,isotropicandhomogeneousuniverse.Subsequently,weperformthecanonicalquantizationproceduretotheHamiltoniantoobtaintheWheeler–DeWittequation.SolvingtheWheeler–DeWittequationandemployingthedeBroglie–Bohminterpretationtothewavefunctionoftheuniverse,weobtainanewversionofspatiallyflatFriedmannequationfortheearlyuniversewherethescalefactoroftheuniverseistakentobesufcientlysmall.

  • 标签: 量子宇宙学 德布罗意 早期阶段 玻姆 哈密顿形式 正则
  • 简介:BythesymboliccomputationandHirotamethod,thebilinearformandanauto-Bcklundtransformationforavariable-coefficientKorteweg-deVriesequationwithnonuniformitiesaregiven.Then,theN-solitonicsolutionintermsofWronskianformisobtainedandverified.Inaddition,itisshownthatthe(N-1)-andN-solitonicsolutionssatisfytheauto-BcklundtransformationthroughtheWronskiantechnique.

  • 标签: KDV方程 变量系数 双线性转换 孤立解
  • 简介:采用硝酸铟、硝酸铜和高分子材料作为静电纺丝的前驱体溶液,经过静电纺丝及高温煅烧,获得一维氧化铟/氧化铜复合纳米纤维,制成气体传感器,并对其气敏性进行测试及分析。

  • 标签: 静电纺丝 纳米纤维 气敏特性
  • 简介:TheeffectsofSO2,SO3ondenovosynthesisofpolychlorinateddibenzo-p-dioxins(PCDDs)anddibenzofurans(PCDFs)werestudiedusingmodelflyashesincorporatingcopperoxideandactivatedcarbon.ItwasfoundthattheinhibitiveeffectofSO2onPCDD/FsformationissimilartothatofSO3.Toinvestigatetheinhibitionmechanism,CuSO4formationsfrombothCuOandCuCl2wereexamined.TheabilityofSO3toconvertCuCl2andCuOonasilicasupportintosulfateismuchstrongerthanthatofSO2.However,replacingsilicabyactivatedcarbonleadstoamuchhighconversionofCuCl2toCuSO4inthepresenceofSO2.ThepromotionbyactivatedcarbonisexplainedbythereductionofCuCl2toCu2Cl2andtheeventualconversionofCu2Cl2intoCuSO4isthemaininhibitionmechanismofSO2ondenovosynthesisofPCDD/Fs.

  • 标签:
  • 简介:以Pd/C为催化剂,以NaI为助催剂,以无水乙醇为溶剂,进行了苯胺氧化羰基化反应。研究了苯胺氧化羰基化的最佳工艺条件,解释了碘化钠在本反应中所起的助催作用。在170℃,反应两小时后,Pd/C显示了高活性(97.49%)和高选择性(85.26%)。最后,提出了苯胺氧化羰基化反应的机理。

  • 标签: 苯胺 氨基甲酸酯 羰基化 机理
  • 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.

  • 标签:
  • 简介:Inthispaper,eighttypesof(1-+1)-dimensionalsimilarityreductionswhichcontainvariablecoefficientequation,areobtainedforthegeneralizedKdVequationin(2+1)-dimensionalspacearisingfromthemultidimensionalisospectralflowsassociatedwiththesecond-orderscalaroperatorsbyusingthedirectmethod.Inaddition,thecnoidalwavesolutionanddromion-likesolutionarealsoderivedbyusingthereducednonlinearordinarydifferentialequations.The(1+1)dromionobtainedbyLou[J.Phys.A28(1995)7227]andZhang[Chin.Phys.9(2000)1]isonlyaspecialcaseofourresults.Moreover,somepropertiesofthedromion-likesolutionsareanalyzed.``

  • 标签: GENERALIZED KDV equation similarity reduction Painlevé-I equation Painlevé-II equation cnoidal
  • 简介:利用温度场计算结果,计算了激光辐照下金属铁氧化膜厚度的增长及氧化放热;利用多层膜反射理论,结合氧化膜厚度,分析了氧化膜导致的激光吸收增强效应.结果表明,波长为1.035μm激光在功率密度为2kW·cm-2辐照期间,氧化放热对温度场的贡献很小,对工程应用来说可以忽略,而氧化膜带来的吸收增强效应影响较大,不能忽略.

  • 标签: 氧化 氧化放热 多层膜反射 激光耦合系数
  • 简介:TQ171.652005032360利用计算机辅助装调检测矩形大口径离轴非球面的方法研究=Studyontestingmethodsoflarge-aperturerectangleoff-axisasphericalsurfacewithcomputeraidedalignment[刊,中]/杨晓飞(中科院长春光机所.吉林,长春(130022)),韩昌元∥光学技术.-2004,30(5).-532-534通过非球面的零位补偿法,完成了对矩形大口径离轴非球面镜的检测。先用光学设计软件Zemax从理论上分

  • 标签: 工艺与设备 光学加工 离轴非球面 加工技术 精度要求 调整量