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简介：对在量chromodynamics(QCD)的nonperturbative政体的夸克动力学的描述的一条计量器不变的途径的主要方面首先被考察。在构造计量器不变的草地功能的平行运输操作的角色然后被介绍，并且为相互作用的表示的威尔森环的关联被强调。基于为平行运输操作的多角形的线的使用，最近的开发被介绍。一个integro微分的方程，为沿着一个单身者，与一个阶段因素定义的夸克草地功能获得了直线片断，确切被解决并且在在large-Nc限制的二维的QCD的情况中的经分解。解决方案为夸克显示动态集体产生现象，与比简单的杆强壮的分支切割奇特的一个无限的数字。

简介：我们在拓扑的动力学在混乱理论的最近的发展给一篇摘要，集中于LiYorke混乱，Devaney混乱，分布混乱，积极的拓扑的熵，微弱地混合等等设定，并且他们的关系。

简介：Inordertoprovidethebasisforparameterselectionofvocaldiseasesclassification,anonlineardynamicmodelingmethodisproposed.Abiomechanicalmodelofvocalcordswithpolyporparalysis,whichcouplestoglottalairflowtoproducelaryngealsoundsource,isintroduced.Andthenthefundamentalfrequencyanditsperturbationparametersaresolved.Poincaresectionandbifurcationdiagramareappliedtononlinearanalysisofmodelvibration.Bychangingthepathologicalparametersorsubglottalpressure,thechangesoffundamentalfrequencyandLyapunovexponentsareanalyzed.Thesimulationresultsshowthat,vocalcordparalysisreducesthefundamentalfrequency,andthechaosoccursonlywithinacertainpressurerange;whilevocalcordwithapolypdon’treducethefundamentalfrequency,chaosdistributesthroughouttheentirerangeofpressure.Thereforethisstudyishelpfulforclassificationofpolypandparalysisbytheacousticdiagnoses.

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简介：Wediscussthedynamicsofultrashortpulsedlaserexcitationinbulkopticalsilica-basedglasses(fusedsilicaandborosilicateBK7)well-abovethepermanentmodificationthreshold.Weindicatesubsequentstructuralandthermomechanicalenergyrelaxationpathsthattranslateintopositiveandnegativerefractiveindexchanges,compressionandrarefactionzones.Iffastelectronicdecayoccursatlowexcitationlevelsinfusedsilicaviaself-trappingofexcitons,forcarrierdensitiesinthevicinityofthecriticalvalueattheincidentwavelength,persistentlong-livingabsorptivestatesindicatetheachievementoflowviscositymatterstatesmanifestingpressurerelaxation,rarefaction,voidopeningandcompactionintheneighboringdomains.Anintermediateps-longexcitedcarrierdynamicsisobservedforBK7intherangecorrespondingtostructuralexpansionandrarefaction.Theamountofexcitationandthestrengthofthesubsequenthydrodynamicevolutioniscriticallydependentonthepulsetimeenvelope,indicativeofpotentialoptimizationschemes.

简介：Westudythedynamicsofthecubic–quinticnonlinearSchr?dingerequationbythesymplecticmethod.Thebehaviorsoftheequationarediscussedwithharmonicallymodulatedinitialconditions,andthecontributionsfromthequintictermarediscussed.Weobservetheellipticorbit,homoclinicorbitcrossing,quasirecurrence,andstochasticmotionwithdifferentnonlinearparametersinthissystem.Numericalsimulationsshowthatthechangingprocessesofthemotionofthesystemandthetrajectoriesinthephasespacearevariousfordifferentcubicnonlinearparameterswiththeincreaseofthequinticnonlinearparameter.

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简介：Hydrodynamicpropertiesandstructureofstrongshockwavesinclassicaldenseheliumaresimulatedusingnon-equilibriummoleculardynamicsmethods.Theshockspeedinthesimulationreaches100km/sandtheMachnumberisover250,whichareclosetotheparametersofshockwavesintheimplosionprocessofinertialconfinementfusion.Thesimulationsshowthatthehigh-Mach-numbershockwavesindensemediahavenotabledifferencesfromweakshockwavesorthoseindilutegases.Theseresultswillprovideusefulinformationontheimplosionprocess,especiallythestructureofstrongshockwavefront,whichremainsanopenquestioninhydrodynamicsimulations.

简介：Overthepastdecadetheintegrationofultrafastspectroscopywithnanosciencehasgreatlypropelledthedevelopmentofnanoscience,asthekeyinformationgleanedfromthemechanisticstudieswiththeassistanceofultrafastspectroscopyenablesadeeperunderstandingofthestructure–functioninterplayandvariousinteractionsinvolvedinthenanosystems.Thismini-reviewpresentsanoverviewoftherecentadvancesachievedinourultrafastspectroscopylaboratorythataddresstheultrafastdynamicsandrelatedmechanismsinseveralrepresentativenanomaterialcomplexsystemsbymeansoffemtosecondtime-resolvedtransientabsorptionspectroscopy.Weattempttoconveyinstructive,consistentinformationregardingtheimportantprocesses,pathways,dynamics,andinteractionsinvolvedinthenanomaterialcomplexsystems,mostofwhichexhibitexcellentperformanceinphotocatalysis.

简介：Thecollectiveresponseofelectronsinanultrathinfoiltargetirradiatedbyanultraintense(6×1020Wcm-2)laserpulseisinvestigatedexperimentallyandvia3Dparticle-in-cellsimulations.Itisshownthatifthetargetissufficientlythinthatthelaserinducessignificantradiationpressure,butnotthinenoughtobecomerelativisticallytransparenttothelaserlight,theresultingrelativisticelectronbeamiselliptical,withthemajoraxisoftheellipsedirectedalongthelaserpolarizationaxis.Whenthetargetthicknessisdecreasedsuchthatitbecomesrelativisticallytransparentearlyintheinteractionwiththelaserpulse,diffractionofthetransmittedlaserlightoccursthroughasocalled‘relativisticplasmaaperture’,inducingstructureinthespatial-intensityprofileofthebeamofenergeticelectrons.Itisshownthattheelectronbeamprofilecanbemodifiedbyvariationofthetargetthicknessanddegreeofellipticityinthelaserpolarization.

简介：Weproposedynamicterahertz(THz)emissionmicroscopy(DTEM)tovisualizetemporal–spatialdynamicsofphotoexcitedcarriersinelectronicmaterials.DTEMutilizesTHzpulsesemittedfromasamplebyprobepulsesirradiatedafterpumppulseirradiationtoperformtime-resolvedtwo-dimensionalmappingoftheTHzpulseemission,reflectingvariouscarrierdynamics.Usingthismicroscopy,weinvestigatedcarrierdynamicsinthegapregionoflow-temperature-grownGaAsandsemi-insulatingGaAsphotoconductiveswitchesoftheidentical-dipoletype.TheobservedDTEMimagesarewellexplainedbythechangeintheelectricpotentialdistributionbetweentheelectrodescausedbythescreeningeffectofthephotoexcitedelectron-holepairs.

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简介：ConsidertheCauchyproblemsforann-dimensionalnonlinearsystemoffluiddynamicsequations.ThemainpurposeofthispaperistoimprovetheFouriersplittingmethodtoaccomplishthedecayestimateswithsharpratesoftheglobalweaksolutionsoftheCauchyproblems.WewillcoupletogethertheelementaryuniformenergyestimatesoftheglobalweaksolutionsandawellknownGronwall'sinequalitytoimprovetheFouriersplittingmethod.ThismethodwasinitiatedbyMariaSchonbekinthe1980'stostudytheoptimallongtimeasymptoticbehavioursoftheglobalweaksolutionsofthenonlinearsystemoffluiddynamicsequations.Asapplications,thedecayestimateswithsharpratesoftheglobalweaksolutionsoftheCauchyproblemsforn-dimensionalincompressibleNavier-Stokesequations,forthen-dimensionalmagnetohydrodynamicsequationsandformanyotherveryinterestingnonlinearevolutionequationswithdissipationscanbeestablished.

简介：复杂系统除了受到不确定性的影响以外,还常常演化为多重时间尺度和(或)多重空间尺度。因此,相应的随机偏微分方程模型包含了时间空间上的多尺度。段金桥与王伟的新书《EffectiveDynamicsofStochasticPartialDifferentialEquations(随机偏微分方程的有效动力学)》重点研究具有快慢时间尺度及大小空间尺度的随机偏微分方程,将平均、慢流形、均匀化等基本技巧发展到随机偏微分方程中,从中萃取出有效动力学。这本书之所以提出有效动力学的原因有二:一方面,有效动力学正

简介：Broadband（1.6–18THz）terahertztime-domainspectroscopy（THz-TDS）andtime-resolvedterahertzspectroscopy（TRTS）wereperformedona54μmthickchalcogenideglass(As30Se30Te40)samplewithatwo-colorlaser-inducedairplasmaTHzsystemintransmissionandreflectionmodes,respectively.Twoabsorptionbandsat2–3and5–8THzwereobserved.TRTSrevealsanultrafastrelaxationprocessofthephotoinducedcarrierresponse,welldescribedbyarateequationmodelwithafiniteconcentrationofmid-bandgaptrapstatesforself-trappedexcitons.ThephotoinducedconductivitycanbewelldescribedbytheDrude–Smithconductivitymodelwithacarrierscatteringtimeof12–17fs,andweobservesignificantcarrierlocalizationeffects.Afastrefractiveindexchangewasobserved100fsbeforetheconductivityreacheditsmaximum,with2ordersofmagnitudelargeramplitudethanexpectedfortheopticallyinducedTHzKerreffect,indicatingthatfreecarriersareresponsibleforthetransientindexchange.