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13 个结果
  • 简介:Theinvestigationofelectrochromiceffectofcorona-polednonlinearopticalpolymerfilmsisaneffectivemethodfortheestimationofpolinglevelandtheselectionofpolingconditions.ThepolingelectricfieldEpandorientationalorderparameterΦ,whicharetheimportantparameterstopredictd33ofpoledfilms,canbecalculatedbyasimpleoperationfromthenumberofredshiftofchargetransferabsorptionband.Thecalculatedresultsareingoodagreementwiththeexperimentaldata.

  • 标签: Nonlinear optical POLYMER POLING Corona-poled film
  • 简介:动态系统被考虑的流行病毒传播人口的一个类。用功能的homotopic分析方法,第一,起始的近似功能被选择。然后,任意的顺序近似分析答案连续地被获得。最后,获得的近似分析答案的精确性被描述。为流行病毒传播人口的各种各样的物理参数的影响动态系统被讨论。

  • 标签: 传播 非线性 功能的印射 O231.2 Q141 R181.2
  • 简介:Wereportonasystematicexperimentalstudyonthefluorescencespectraproducedfromafemtosecondlaserfilamentinairunderahighelectricfield.Theelectricfieldalonewasstrongenoughtocreatecoronadischarge(CD).Fluorescencespectrafromneutralandionicairmoleculesweremeasuredandcomparedwithpurehigh-voltageCDandpurelaserfilamentation(FIL).Amongthem,highelectricfieldassistedlaserFILproducednitrogenfluorescencemoreefficientlythaneitherpureCDorpureFILprocesses.Thenonlinearenhancementoffluorescencefromtheinteractionofthelaserfilamentandcoronadischargingelectricfieldresultedinamoreefficientionizationalongthelaserfilamentzone,whichwasconfirmedbythespectroscopicmeasurementofbothionization-inducedfluorescenceandplasma-scattered800nmlaserpulses.Thisisbelievedtobethekeyprecursorprocessforfilament-guideddischarge.

  • 标签: FEMTOSECOND LASER FILAMENTATION FILAMENT induced fluorescence
  • 简介:ThepaperpresentsthebasicmodelforthetransmissiondynamicsofWestNilevirus(WNV).Themodel,whichconsistsofsevenmutually-exclusivecompartmentsrepresentingthebirdsandvectordynamics,hasalocally-asymptoticallystablediseasefreeequilibriumwhenevertheassociatedreproductionnumber(R0)islessthanunity.Asrevealin[3,20],theanalysesofthemodelshowtheexistenceofthephenomenonofbackwardbifurcation(wherethestabledisease-freeequilibriumofthemodelco-existswithastableendemicequilibriumwhenthereproductionnumberofthediseaseislessthanunity).Itisshown,thatthebackwardbifurcationphenomenoncanberemovedbysubstitutingtheassociatedstandardincidencefunctionwithamassactionincidence.Analysisofthereproductionnumberofthemodelshowsthat,thediseasewillpersist,wheneverR0>1,andincreaseinthelengthofincubationperiodcanhelpreduceWNVburdeninthecommunityifacertainthresholdquantities,denotedby△band△varenegative.Ontheotherhand,increasingthelengthoftheincubationperiodincreasesdiseaseburdenif△b>0and△v>0.Furthermore,itisshownthataddingtimedelaytothecorrespondingautonomousmodelwithstandardincidence(consideredin[2])doesnotalterthequalitativedynamicsoftheautonomoussystem(withrespecttotheeliminationorpersistenceofthedisease).

  • 标签: 西尼罗河病毒 模型 数学分析 离散时滞 局部渐近稳定 无病平衡点
  • 简介:Thestructureandkineticsofthecomplexformedbyhyaluronicacid(HA)andpoly(L-lysine)(PLL)werestudiedbytimeresolvedlaserlightscattering,TEM,andAFM.BecauseHAhasahydrophilicbackbone,thecomplexesformedbyHAandPLLaredifferentfromthoseformedbyoppositelychargedpolyelectrolytesbothhavinghydrophobicbackbones.Insteadofformingstrongaggregatesandevenprecipitates,thecomplexinthepresenceofexcessHAisstableinthestudiedtimeperiod.Moreimportantly,thecomplexspontaneouslyformscore-coronastructurebytherearrangementofHAchains.ThecoreiscomposedofcomplexrichofPLLandthecoronaismainlyHA.FurtheranalysisshowsthatthehydrogenbondformedbyHAcreatesabarrierhinderingthefurtherrelaxationofHAchains.Theautomaticformationofcore-coronastructurebyPLL/HAishelpfulnotonlytounderstandtherelaxationofpolyelectrolyteincomplex,butalsotodevelopdrugcarrierswithdesirableproperties.

  • 标签: POLYELECTROLYTE complex Core-corona STRUCTURE Hyaluronic acid
  • 简介:某些疾病被知道引起变化在物理并且房间的biomechanical性质。这些在其它之中包括癌症,疟疾,和镰刀房间贫血症。典型地,如此的物理性质变化能导致房间僵硬的几褶层增加或减少,它是重要的并且能导致严重病理和最终的灾难的故障身体功能。当有时开发了生物化学、生物的试金检测疾病的发作或存在,总是有需要开发更快速、精确、敏感的方法检测并且诊断疾病。Biomechanical性质变化能起一个重要作用在这方面。因此,对疾病biomechanics的研究不能仅仅给我们位于疾病前进下面的机制的深入的知识,但是能也为察觉和诊断用作一个强大的工具。这篇文章提供一些卓见进机会因为在疾病的发作或前进期间在细胞的机械性质换掉怎么重要,能为察觉和诊断作为有用工具被利用。我们将也展示已经被开发了执行如此的察觉和诊断的几种技术。

  • 标签: 生物力学特性 疾病诊断 细胞 应用 人类 物理性质
  • 简介:SYNTHESISANDANTI-HUMANIMMUNODEFICIENCYVIRUS-1(HIV-1)ACTIVITYOF9-(2-PHOSPHONYLMETHOXYETHYL)ADENINE(1)ANDITSREGIOISOMER3-(2-PHO...

  • 标签: HIV-1