简介：Extractionofthein-mediumpropertiesofstrangeparticlesfromheavy-ioncollisionsisverycomplicated,sincehenucleardensityvariesintheevolutionofnucleus-nucleuscollisions.Toavoidtheuncertaintiesofthebaryonensitiesduringthestageofstrangeparticleproduction,onecaninvestigateproton-nucleuscollisionswheretheucleardensityisdefinitearoundthesaturationdensity.DynamicsofstrangeparticlesproducedintheprotoninduceduclearthereactionsnearthethresholdenergieshasbeeninvestigatedwithintheLanzhouquantumoleculardynamics(LQMD)transportmodel.Thein-mediummodificationsonparticleproductionindensenuclearmatterareconsideredthroughthecorrectionstotheelementarycrosssectionsviatheeffectivemassandhemean-fieldpotentials[1].

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

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简介：WehavecomprehensivelyinvestigatedthefrustratedJ1-J2-J3Heisenbergmodelonasimplecubiclattice.Thismodelallowsthreeregimesofmagneticorder,viz.,(π;π;π),(0;π;π)and(0;0;π),denotedasAF1,AF2,andAF3,respectively.Theeffectsoftheinterplayofneighboringcouplingsonthemodelarestudiedintheentiretemperaturerange.Thezerotemperaturemagneticpropertiesofthismodelarediscussedutilizingthelinearspinwave(LSW)theory,nonlinearspinwave(NLSW)theory,andGreen’sfunction(GF)method.ThezerotemperaturephasediagramsevaluatedbytheLSWandNLSWmethodsareillustrated,andareobservedtoexhibitdifferentparameterboundaries.Incertainregionsandalongtheparameterboundaries,thepossiblephasetransformationsdrivenbytheparametersarediscussed.TheresultsobtainedusingtheLSW,NLSW,andGFmethodsarecomparedwiththoseobtainedusingtheseriesexpansion(SE)method,andareobservedtobeingoodagreementwhenthevalueofJ2isnotclosetotheparameterboundaries.ThegroundstateenergiesobtainedusingtheLSWandNLSWmethodsareclosetothatobtainedusingtheSEmethod.Atfinitetemperatures,onlytheGFmethodisemployedtoevaluatethemagneticproperties,andthecalculatedphasediagramisobservedtobeidenticaltotheclassicalphasediagram.Theresultsindicatethatattheparameterboundaries,atemperature-drivenfirst-orderphasetransitionbetweenAF1andAF2mayoccuralongtheboundaryline.AlongtheAF1-AF3andAF2-AF3boundarylines,AF3islessstablethanAF1andAF2.OurcalculatedcriticaltemperatureagreeswiththatobtainedusingMonteCarlosimulationsandpseudofermionfunctionalrenormalizationgroupscheme.

简介：一次函数是初中学生学习函数的第一个阶段,其基础性和重要性不言而喻,中考对函数的考查属重头戏,对一次函数的考查十分关注.通过一题多变把一次函数的有关基础知识横纵向联系,把以前学习的方程（组）、不等式（组）等统一起来认识,逐步达到新旧知识的融会贯通,从而进一步体会一次函数的重要性,通过一题多变能更全面、更快捷地掌握知识和技能.

简介：本文以有源的热传导问题为例，介绍一种直接从物理上过渡的解非齐次泛定方程定解问题的方法．免去了较为抽象和繁杂的数学推导，在物理上较为直观、明了，并能起到举一反三的教学效果。

简介：结合线性二次型性能指标最优控制理论的设计方法,通过具体实例介绍在Matlab5.3环境下完成一个线性二次型最优控制器的设计过程,并研究了参数变化对最优控制系统的影响。

简介：模型试验我们计划两轮试验。第一轮安排在1991-1992学年．现已开始；第二轮将在1992-1993学年进行。大约20所学校表示了成为IUPP试验点的愿望。我们总的目标是通过这两年的试验把代表不同学术条件的学校一研究性的大学、综合性大学、四年制学院和两年制学院都能包括在试验范围之内。

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简介：大学基础物理学规划（IUPP），针对的是微积分水平的基础物理课程的改革，我们认识到随着微积分水平的基础课程的变化，将会需要对整个物理课程（即从高中到专业的课程）重新评价，IUPP只是一个开端。这个计划是由美国物理教师协会、美国物理研究院和美国物理学会发起的，并得到美国国家科学基金会的大学科学工程和数学部门的赞助。

简介：<正>Westudythenonlineardynamicsoftwo-componentBose-Einsteincondensatesinone-dimensionalpe-riodicopticallatticepotentials.Thestationarystateperturbationsolutionsofthecoupledtwo-componentnonlinearSchr?dinger/Gross-Pitaevskiiequationsareconstructedbyusingthedirectperturbationmethod.Theoreticalanalysisrevelsthattheperturbationsolutionisthechaoticone,whichindicatestheexistenceofchaosandchaoticregioninparameterspace.Thecorrespondingnumericalcalculationresultsagreewellwiththeanalyticalresults.Byapplyingthechaoticperturbationsolution,wedemonstratetheatomicspatialpopulationandtheenergydistributionofthesystemarechaoticgenerally.

简介：Newmetal-freeorganicdyesensitizerscontainingmono-triphenylamineorbis-triphenylamineastheelectrondonor,athiopheneastheπ-conjugatedsystem,andacyanoacrylicacidmoietyastheelectronacceptorweresynthesized.Theopticalandelectrochemicalpropertiesofthedyeswereinvestigated,andtheirperformanceassensitizersinsolarcellswasevaluated.Dye-sensitizedsolarcellsbasedondyecontainingbis-triphenylamineastheelectrondonorproducedaphoton-to-currentconversionefficiencyof6.06%(Jsc=14.21mA/cm~2,Voc=0.62V,ff=0.69)under100mW/cm~2simulatedAM1.5Gsolarirradiation(100mW/cm~2).

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简介：大学基础物理规划(IUPP)的宗旨是改革各种含微积分物理课程。本规划是由美国教师协会、美国物理研究所、美国物理学会支持的。IUPP由（美)国家科学基金科学工程和数学办公室提供资金。

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