简介：Theuseofliving,alkyllithium-initiatedanionicpolymerizationtopreparechain-endfunctionalizedpolymersandheteroarm,star-branchedpolymersisdiscussed.Thescopeandlimitationsofspecificterminationreactionswithavarietyofelectrophilicspeciesareillustratedforcarbonation,hydroxyethylation,amination,andsulfonation.Themethodologyofusingsubstituted1,1-diphenylethylenestoprovideageneral,quantitativefunctionalizationprocedureisoutlinedandillustratedwithexamplesofamineandphenolend-functionalization.Amethodologyisdescribedforthesynthesisoffunctionalized,star-branchedcopolymerswithcompositionallyheterogeneousarmsofcontrolledmolecularweightandnarrowmolecularweightdistributionusing1,3-bis(1-pbenylethenyl)benzene.

简介：Asymmetrictree-likebranchednetworksareexploredbygeometricalgorithms.Basedonthenetwork,ananalysisofthethermalconductivityispresented.Therelationshipbetweeneffectivethermalconductivityandgeometricstructuresisobtainedbyusingthethermal-electricalanalogytechnique.Inallstudiedcases,aclearbehaviourisobserved,whereangle(δ,θ)amongparentbranchingextendedlines,branchesandparameterofthegeometricstructureshavestrongereffectsontheeffectivethermalconductivity.Whentheangleδisfixed,theopticaldiameterratioβisdependentonangleθ.Moreover,γandmarenotrelatedtoβ.Thelongerthebranchis,thesmallertheeffectivethermalconductivitywillbe.Itisalsofoundthatwhentheangleθ<δ/2,thehighertheiterationmis,thelowerthethermalconductivitywillbeandittendstozero,otherwise,itisbiggerthanzero.Whenthediameterratioβ1<0.707andangleδisbigger,theoptimalkoftheperfectratioincreaseswiththeincreaseoftheangleδ;whenβ1>0.707,theoptimalkdecreases.Inaddition,theeffectivethermalconductivityisalwayslessthanthatofsinglechannelmaterial.Thepresentresultsalsoshowthattheeffectivethermalconductivityoftheasymmetrictree-likebranchednetworksdoesnotobeyMurray'slaw.

简介：BymakinguseofThiele-typebivariatebranchedcontinuedfractionsandSumelsoninverse,weconstructafewkindsofbivariatevectorvaluedrationalinterpolonts(BVRIs)overrectangulargridsandfindoutcertainrelationsamongtheseBVRIssuchasboundaryidentityandduality.

简介：Triplebranchedcontinuedfractions(TBCFs)areconstructedbymeansofwell-defineThiele-typepartialinverteddifferences.Thecharacterizatioontheorem,uniquenesstheoremandsomeprojectionidentitypropertiesareobtainedforvectorvaluedrationalinterpolantshyTBCFs.

简介：Anoveltri-branchedcopolymerissynthesizedtoshowstrongtwo-photonabsorptionandintensetwo-photonabsorptioninducedfluorescenceemissionundertheexcitationofthefemtosecondlaserpulsesatwavelengthof80Ohm.Thedynamicsoftheexcitedstatewasmeasuredbythepump-probetechnique.Inaone-colourpump-probeexperimentat800nm,therewasanultrafasttransientabsorption,followedbyothertworelaxationprocesses.Thetwo-photonabsorptionprocesscouldbeoneoriginforthisultrafastphotoabsorptionsignal,whichwasfurtherprovenbytwo-colourpump-probeexperiments.Theothertwodecayingprocessesinthetransientabsorptiondynamicshavelifetimeofabout15psand129ps,whichreflecttheintrabandvibrationalrelaxationandthedecayoftwo-photonexcitedstate,respectively.

简介：Avertical(laterallyaveraged)two-dimensionalhydrodynamicmodelisdevelopedfortides,tidalcurrent,andsalinityinabranchedestuarinesystem.ThegoverningequationsaresolvedwiththehydrostaticpressuredistributionassumptionandtheBoussinesqapproximation.Anexplicitschemeisemployedtosolvethecontinuityequations.ThemomentumandmassbalanceequationsaresolvedimplicitlyintheCartesiancoordinatesystem.Thetributariesaregovernedbythesamedynamicequations.Acontrolvolumeatthejunctionsisdesignedtoconservemassandvolumetransportinthefinitedifferenceschemes,basedonthephysicalprincipleofcontinuummediumoffluid.Predictionsbythedevelopedmodelarecomparedwiththeanalyticsolutionsofsteadywind-drivencirculatoryflowandtidalflow.Themodelresultsforthevelocitiesandwatersurfaceelevationscoincidewithanalyticresults.ThemodelisthenappliedtotheTanshuiRiverestuarinesystem.Detailedmodelcalibrationandverificationhavebeenconductedwithmeasuredwatersurfaceelevations,tidalcurrent,andsalinitydistributions.Theoverallperformanceofthemodelisinqualitativeagreementwiththeavailablefielddata.ThecalibratedandverifiednumericalmodelhasbeenusedtoquantifythetidalprismandflushingrateintheTanshuiRiver-TahanStream,HsintienStream,andKeelungRiver.

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简介：Thispaperconstructsanewkindofblockbasedbivariateblendingrationalinterpolationviasymmetricbranchedcontinuedfractions.Theconstructionprocessmaybeoutlinedasfollows.Thefirststepistodividetheoriginalsetofsupportpointsintosomesubsets(blocks).Thenconstructeachblockbyusingsymmetricbranchedcontinuedfraction.FinallyassembletheseblocksbyNewton’smethodtoshapethewholeinterpolationscheme.OurnewmethodoffersmanyflexiblebivariateblendingrationalinterpolationschemeswhichincludetheclassicalbivariateNewton’spolynomialinterpolationandsymmetricbranchedcontinuedfractioninterpolationasitsspecialcases.Theblockbasedbivariateblendingrationalinterpolationisinfactakindoftradeoffbetweenthepurelylinearinterpolationandthepurelynonlinearinterpolation.Finally,numericalexamplesaregiventoshowtheeffectivenessoftheproposedmethod.

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简介：双人脚踏车催化系统，由乙烯二度(indenyl)组成有二不同cocatalysts，alkylaluminum(diethylaluminium氯化物或trialkylaluminum)和methylaluminoxane的锆二氯化物，在作为唯一从乙烯准备分叉的聚乙烯被采用单体。催化系统racet(Ind)2ZrCl2/AlEt2Cl/MAO展出了高加入(29.0/1000C)。oligomerization和copolymerization反应在双人脚踏车调节催化系统，以及不同cocatalysts，在催化活动和获得的聚合物的性质有效果例如融化温度，crystallinity，分子的重量和分子的重量分发。而且，oligomerization反应条件是在改变聚乙烯的性质和结构的主要因素。

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简介：Nickel-basedcatalyst[N,N]NiBr2,inwhich[N,N]standsforN-(2,6-diisopropylphenyl)pyridine-2-carboxaldimine,showshighactivityforethylenepolymerizationinthepresenceoforganoaluminumcompoundsunderhighethylenepressuretoyieldpolyethylenecharacteristicoflowmolecularweightandhighlybranchedchains.Tolueneasthesolventismoreinfavorofcatalystactivity,highermolecularweightandbranchedchainsinpolyethylenestructureascomparedtohexanesolvent.

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