简介：　　Inrecentyears,constrained-geometrygroup4metallocenecatalystshavereceivedconsiderableattentionduetotheirimportanceincommercialapplication［1］.Thestructuralfeatureofthistypeofmetallocenesisthatoneofthetwocyclopentadienylgroupsinansa-metallocenecomplexesisreplacedbyaheteroatom,suchasnitrogen,phosphorus［2］oroxygen［3］andetc.Incomparisonwithbiscyclopentadienylmetallocenes,theconstrained-geometrymetallocenecatalystshavemoreopenspaceforolefincoordination,whichallowslargerα-olefinstocopolymerizewithethyleneeasily.ThiskindofcompoundswouldhaveabettercatalyticperformanceifaphenolgroupwereintroducedintotheligandframeworksincetheOinthephenolgroupismorenegativethanN,Pintheamido-orphosphido-groups,andthewholemoleculewiththephenol-cyclopentadienylligandwillbemorestablecomparedtothecomplexeswithamido-or……

简介：Weproposeacatalysis-selectmigrationdrivenevolutionmodeloftwo-species(A-andB-species)aggregates,whereoneunitofspeciesAmigratestospeciesBunderthecatalystsofspeciesC,whileunderthecatalystsofspeciesDthereactionwillbecomeoneunitofspeciesBmigratingtospeciesA.MeanwhilethecatalystaggregatesofspeciesCperformself-coagulation,asdothespeciesDaggregates.Westudythiscatalysis-selectmigrationdrivenkineticaggregationphenomenausingthegeneralizedSmoluchowskirateequationapproachwithCspeciescatalysis-selectmigrationratekernelK(k;i,j)=KkijandDspeciescatalysis-selectmigrationratekernelJ(k;i,j)=Jkij.Thekineticevolutionbehaviourisfoundtobedominatedbythecompetitionbetweenthecatalysis-selectimmigrationandemigration,inwhichthecompetitionisbetweenJD0andKC0(D0andC0aretheinitialnumbersofthemonomersofspeciesDandC,respectively).WhenJD0KC0>0,theaggregatesizedistributionofspeciesAsatisfiestheconventionalscalingformandthatofspeciesBsatisfiesamodifiedscalingform.AndinthecaseofJD0KC0<0,speciesAandBexchangetheiraggregatesizedistributionsasintheaboveJD0KC0>0case.

简介：Ring-openingpolymerizationofε-caprolactone（CL）catalyzedbylanthanocenes,O（C2H4C5H3CH3）2YCl（Cat-YCl）andMe2Si[（CH3）3SiC5H3]2NdCl（Cat-NdCl）hasbeencarriedoutforthefirsttime.IthasbeenfoundthatbothyttroceneandneodymoceneareveryefficienttocatalyzethepolymerizationofCL,givinghighmolec-ularweightpoly（ε-caprolactone）（PCL）.Theeffectsof[cat]/[ε-CL]molarratio,polymeriza-tiontemperatureandtime,aswellassolventswereinvestigatedandpolymerizationtem-peratureisfoundtobethemostimportantfactoraffectingthepolymerization.ThebulkpolymerizationgiveshighermolecularweightPCLandhigherconversionthanthatinsolu-tionpolymerization.NaBPh4wasfoundtopromotethepolymerizationofε-caprolactone,andthustoincreaseboththepolymerizationconversionandMWofpoly（ε-caprolactone）.

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简介：Theelectronicstructureof(001)polarsurfaceofcubiczirconiawasstudiedbyGGA(WC)approximation.Wefoundthecubiclatticenear(001)surfaceshowedanintensivetendencytotransfertotetragonallattice.Themetallicstateappearedonboththeterminations.ForO-termination,someO2pstateswerevacatedandholecarriersconcentratedonsurfaceoxygen-ions.ForZr-ermination,someZr4dstatesbecamepartialoccupiedforthelossofO2pstates.Weobservedtheholestatesweremainlylocalizedatthecorrespondingionsonsurfaceforboththeterminations,whilethechargestatesonZr-terminationweredispersedonsurface.

简介：在这研究，trans芪的相片异构化在由使用钠dodecyl硫酸盐(SDS)的微乳液，dodecyl修剪乙醇铵溴化物(DTAB)和cetyl整修的油(W/O)在水里被执行乙醇铵溴化物(CTAB)作为表面活化剂分别地。这反应上的微乳液的催化效果是仔细与表面活化剂的结构有关。当没有photosensitizer9,10-dicyanoanthracene(DCA)时，，有更短的恐水病的链的表面活化剂面对DCA被比较喜欢，与一个离子的极的组一起的表面活化剂被比较喜欢。

简介：TheconceptualideasaboutthepositiveeffectsofN-andO-heteroatomsonthereactivityofcarbonsingasificationprocesses,theircatalyticactivityinelectrontransferreactions,aswellastheperformanceoftheelectrodedouble-layersupercapacitorsduetotheirelectron-donatinginfluenceontheπ-conjugatedsystemofgraphenelayershavebeendeveloped.Thisinfluencedecreasesbothworkfunctionandbandgapofcarbons,andalsosignificantlyaffectstheirelectron-donatingproperties.AsaresultofourinvestigationsbasedonquantumchemicalcalculationsofmodelgrapheneclusterswithN-andO-heteroatomsindifferentpositions,prognosticdatahavebeenobtained.ThesedatahavebeenconfirmedbyourexperimentalresultsofcatalyticactivityofcorrespondingcarbonsinH2O2decompositionreaction,theirreactivityingasificationprocesses,andalsotheirperformanceaselectrodesinsupercapacitors.

简介：PolystyreneN-hydroxylsulfonamideresin1waspreparedandusedtocatalyzetheesterificationofn-butanolandaceticanhydride.ThemechanismofcatalyticesterificationprovedbyIRspectraoftheresinswasfoundthatO-HandN-HoftheN-hydroxylsulfonamideresinreactedwiththeaceticanhydriderespectivelytoformtheactiveintermediatepolystyreneN,O-diacetylsulfonamatewhichwascleavedbyn-butanoltoproducebutylacetate.Thecatalyticesterificationbyresin1wasingoodagreementwiththekineticmodelof"bi-bi-ping-pong"mechanism.

简介：Theexperimentwascarriedoutinacylindricaldielectricbarrierdischarge(DBD)reactorassistedwithacatalysttodecomposetolueneunderdifferenthumidity.Inordertoexplorethesynergisticeffectonremovingtolueneinthecatalysis-DBDreactor,thispaperinvestigatedthedecompositionefficiencyandtheenergyconsumptioninthecatalysis-DBDandthenon-catalystDBDreactorsunderdifferenthumidity.Theresultsshowedthatthecatalysis-DBDreactorhadabetterperformancethanthenon-catalysisoneatthehumidityratioof0.4%,andtheremovalefficiencyoftoluenecouldreach88.6%inthecatalysis-DBDreactor,whileitwasonly59.9%inthenon-catalyticreactor.However,therewasnosignificantdifferenceintheremovalefficiencyoftoluenebetweenthetworeactorswhenthehumiditieswere1.2%and2.4%.Additionally,thedegradationproductswerealsoanalyzedinordertogainabetterunderstandingofthemechanismofdecomposingtolueneinacatalysis-DBDreactor.

简介：Fordetailedstudyofcomplexchemicalreactionsmechanismsexperimentisconductedforselectedprivatereactions.Thiscausesaproblemofkineticparametersgetting-thesamesetofrateconstantsmustdescribebothpublicandprivatereactionstages,andalsoageneralmechanism.Inthispaper,solutionofthisproblemforareactionofolefinshydroaluminationisproposed.Tooptimizethecomputationalprocessamethodologyofparallelizationiselaborated.Onthebaseofparallelcomputations,akineticmodelforthereactionassignedisconstructed,andonitsbase,thephysicalandchemicalconclusionsaboutreactionmechanismaredone.

简介：Aseriesofpolymer-supportedtetranuclearrhodiumcarbonylclustercatalystswerepreparedbthereactionofRh4（CO）12withseveralkindsofpolymersupportssuchascrosslinkedpoly（N-vinylpyrrolidone）（PNVP）andcrosslinkedpoly（styrene-co-maleicanhydride）（PMAn）,andsubsequentlywereusedtocatalyzethehydroformylationofolefins.ThecatalystswerecharacterizedbyIR,SEMandXPS.Theinfluenceofthesupportsstructureandcrosslinking,metal’scontentandparticlesizeofthesupportsonthecatalystshydroformylationpropertieswasstudied.Thefactorswhichaffectthecatalyticconversionwerealsoexamined.Theexperimentalresultsshowthatthepolymer-supportedRhclustercatalystspossessveryhighcatalyticactivityandaldehydeselectivityaswellasgoodreproducibility.

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。

简介：甲醇(CH3哦)是有许多使用的重要工业化学药品。工业甲醇合成催化剂典型地由Cu，Zn，和艾尔组成，但是合并稀土元素元素的催化剂的使用被显示了改进催化表演。由于他们的唯一的化学、物理的性质，当在甲醇合成催化剂的稀土元素的使用没有时，在催化作用的稀土元素元素(钪，钇，和lanthanides)的使用一般来说继续了在过去几十年增加，尽管有经常改进性能。几个稀土元素元素的能力(Pr，Ce，Eu，Tb，Yb)做他们容易在氧化状态之间切换为催化剂的许多不同类型有益。然而，为甲醇合成，表面盐基度是一个重要性质，并且稀土元素元素的基本性质能被用来调节催化剂的盐基度。在稀土元素性质和催化性能之间的关联的一个小数字被观察了，但是经常不适用于另外的催化剂。象基本地点，离子的半径，和electronegativity的力量那样的性质被发现了与象活动或选择那样的表演结果相关。

简介：TheSmBaCuMO5+δ(M=Fe,Co,Ni)(SBCM)powdersweresynthesizedbythecitratesol-gelmethodandthepowdersweresinteredtoceramicpellets.ThepowdersandsinteredceramicpelletswerecharacterizedwithXRD,TEMandSEMmeasurements.ThecathodecatalyticperformancesofSBCMceramicpelletsforammoniasynthesiswerestudiedfromwethydrogenanddrynitrogenatatmosphericpressureandlowtemperature,usingSBCMceramicpelletsascathode,Nafionprotonexchangemembraneaselectrolyte,Ni-Ce0.8Sm0....

简介：当他们被介绍进主要的链时，热imidizaiton上的benzimidazole单位的效果被学习poly(amic酸)(泛美航空公司)。PAA-PABZ的热imidization过程由3,3,4,4-biphenyltetracarboxylicdianhydride(BPDA)综合了，2-(4-aminophenyl)-5(6)-aminobenzimidazole(PABZ)被TGA学习，DSC，直接存储器存取，FTIR并且在situFTIR。FTIR并且在situFTIR的结果显示单位充当的benzimidazole一在里面当温度比170低时，加速泛美航空公司的热imidization到polyimide(PI)的situ催化剂?????????????????????????ㄠ?????獩瑯捡楴?????偩???h

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简介：SevendiarylethersweresynthesizedwithpotassiumfluoridecoatedaluminaasastrongbaseandtheadditionofcatalyticamountofPTC.TheyieldofdiaryletherswithadditionofPTCwasmuchhigherthanthatwithoutPTC.Adiscussionofthecatalysismechanismwasgiveninthispaper.

简介：EthylN-cyanomethytbenzenecarboximidatereactedwithaliphaticaldehydesunderthesolid-liquidPTCconditiontogirea-ethoxyphenylmethylene-aminoacrylonitrilederivativesandoxazolinederivatives.Itisaconvenientandnewmethodforsynthesisofβ,β’-dihyroxy-a-aminoacidsbyhydrolysisoftheoxazolinederivatives.

简介：Theapplicationoflaserpulseswithpsecorshorterdurationenablesnonthermalefficientultrahighaccelerationofplasmablockswithhomogeneoushighionenergiesexceedingioncurrentdensitiesof1012Acm-2.Theeffectsofultrahighaccelerationofplasmablockswithhighenergyprotonbeamsareproposedformuonproductioninacompactmagneticfusiondevice.Theproposednewschemeconsistsofanignitionfusionsparkbymuoncatalyzedfusion（μCF）inasmallmirror-likeconfigurationwherelowtemperatureD–Tplasmaistrappedforadurationof1μs.Thisinitialfusionsparkproducessufficientalphaheatinginordertoinitiatethefusionprocessinthemaindevice.Theuseofamulti-fluidglobalparticleandenergybalancecodeallowsustofollowthetemporalevolutionofthereactionrateofthefusionprocessinthedevice.RecentprogressontheICANandIZESTprojectsforhighefficienthighpowerandhighrepetitionratelasersystemsallowsdevelopmentoftheproposeddeviceforcleanenergyproduction.Withtheproposedapproaches,experimentsonfusionnuclearreactionsandμCFprocesscanbeperformedinmagnetizedplasmasinexistingkJ/PWlaserfacilitiesastheGEKKO-LFEX,thePETALandtheORIONorinthenearfuturelaserfacilitiesastheELI-NPRomanianpillar.