简介：Fluorescencespectraofladderlikepolyphenylsilsesquioxane(LPPS)andladderlike1,4-phenylene-bridgedpolyvinylsiloxane(LPPVS)havebeenmeasuredasafunctionoftemperature(4-55℃),indilutetetrahydrofuransolution.Theexcimer(IE)tomonomer(IM)intensityratio(IE/IM)ofLPPSdilutesolutionshowsadoublelinearArrheniusplotwithabreakpointascribabletoatransitiontemperatureTr.Thisbehaviorhasnotbeenfoundforsinglechainpolyorganosiloxanes.WhenIn/EofLPPSwasplottedagainst1/T,italsogaveadoublelinearplotwithonebreakpoint,whichwasfoundinsinglechainpolyorganosiloxanes.ThedifferentbehaviorsbetweenLPPSandsinglechainpolyorganosiloxanesmaybemainlyattributedtotherelativelyrigiddouble-chainmacromolecularbackboneofLPPS.However,theln(IE/IM)ofdiluteLPPVSsolutionversus1/Tshowsasimplelinearvariationwithapositiveslopewhichconfirmsourproposition.ThedifferencebetweenthefluorescenceresultsofLPPSandthoseofLPPVSmaypossiblyderivefromtheirstructuredifferencesandcooperativemotioninbackbonechainbonds.

简介：Anovelgrapheneoxidedopedpoly(hydroxymethylated-3,4-ethylenedioxythiophene)(PEDOT-MeOH/GO)compositefilmwassynthesizedandutilizedasanefficientelectrodematerialforsimultaneousdetectionofrutinandascorbicacid(AA).PEDOT-MeOH/GOfilmsweresynthesizedonglassycarbonelectrode(GCE)byafacileone-stepelectrochemicalapproachandwerecharacterizedbyscanningelectronmicroscopy,UV-Visspectroscopy,FTIRspectraandelectrochemicalmethods.ThenthePEDOT-MeOH/GO/GCEwasappliedsuccessfullyinthesimultaneousdetectionofrutinandAA.TheresultsshowedthattheoxidationpeakcurrentsofrutinandAAobtainedatthePEDOT-MeOH/GO/GCEweremuchhigherthanthoseatthetraditionalconductingpolymerPEDOT/GO/GCE,PEDOT-MeOH/GCE,PEDOT/GCEandbareGCE.Underoptimizedconditions,thelinearrangesforrutinandAAare20nmol/L-10μmol/Land8μmol/L-1mmol/L,respectively.Thedetectionlimitis6nmol/Lforrutinand2μmol/LforAA(S/N=3),whicharelowerthanthoseofthereportedelectrochemicalsensors.

简介：Thestructureofpolyimidefrom1,4-bis(3’,4’-dicarboxyphenoxy)benzeneand4,4’-oxydianilinefilmspecimensbeforeandafterhotstretchinghasbeeninvestigatedbyWAXD,DSCandFTIR.AsevidencedbyboththeWAXDandDSCresults,itcouldbebelievedthatstraininducedcrystallizationdidtakeplaceafterhotstretching.Meanwhile,shiftingpositionandsplittingofsomebandpeaksexistedontheFTIRspectrogramswereexplainedintermsoftheclosepackingofchainsandthechangesofinter-molecularcharge-transferinteractionbetweenimidegroupsandaromaticgroupsuponcrystallization.

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简介：ThepreparationofconductingPPQfilmwasfirstreportedinthepreviouspaper.Itisveryinterestingthatthisfilmishighlysensitivetomoistureinair.ThehydrationanddehydrationofthefilmareaccompaniedbychangenotonlyincolorbutalsoinconductivityandUV-visiblespectrum.TheconductingPPQisreducedtoPPQandlosesitsconductivityafterbeingsoakedinwater.

简介：Poly（β-carboxyethylmethylsiloxane）-LiClO4andpoly（β-alkoxylethylmethylsiloxane）-LiClO4crosslinkedfllmshavebeenprepared.Theionicconductivityofthefilmsdependsonthepolymerspecies,concentrationoflithiumperchlorate,temperatureandcontentofcrosslinkingagent.Theeffectofhighpolarorganicsolvent1,4-butyrolactoneontheionicconductivityandmechanicalpropertiesofpoly（β-carhoxyethylmethylsiloxane）-LiClO4systemwasalsoinvestignied.

简介：Ionicconductivityvaluesforsegmentedpolyetherpolyurethaneurea（PEUU）complexeswithLiClO4weredeterminedandvaluesashighas～1.1×10-4S·cm-1at353Kand～1.0×10-5S·cm-1at306Kwereachieved.TheionicconductivitydatawereanalyzedusingtheVTF（Vogel-Tamman-Fulcher）equationandWLF（Williams-Landel-Ferry）typeequation.Valueshavebeenestimatedforthe"apparent"activationenergiesofiontransportfromVTFequationandtheylieintherange2.70—5.53kJ·mol-1.

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简介：Thiscontributionreportsethylenepolymerizationbehavioroftitaniumcomplexesincorporatingbis(phenoxyimine)ligands.Sixphenoxy-imineTi(IV)complexes{6-R1-2-[CH=N(2,6-difluoro-3,5-diR2-4-R3Ph)]C6H3O}2TiCl2(1:R1=H,R2=H,R3=H;2:R1=H,R2=H,R3=4-vinylphenyl;3:R1=CH3,R2=H,R3=H;4:R1=CH3,R2=H,R3=4-vinylphenyl;5:R1=CH3,R2=F,R3=H;6:R1=CH3,R2=F,R3=4-vinylphenyl)havebeensynthesizedandevaluatedforethylenepolymerizationusingdriedMAO(simplifiedasDMAO)ascocatalyst.AnobviouscatalyticheterogeneityofCat2(Complex2/DMAO)towardsethylenepolymerizationwasobserved,whichwasillustratedbydecreasedactivity,multimodalmolecularweightdistributionandpartiallyimprovedparticlemorphologycomparingwithCat1.Moreover,Cat3exhibits'living'characteristicsintheprocessundercertainconditions(25°C,lessthan20min).Otherwise,themoderatetohighethylenepolymerizationactivityofca.105-106gPE/(molTi·h)andhighmolecularweight(Mw=105-106)ofpolyethylenecanbeobtainedbychangingtheskeletonstructureofthesecomplexes.

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简介：Thetreatmentandresourcereuseof1,2,4-acidproducingwastewaterbyself-mademacroporousadsorptionresinND,A-107wasstudiedinthispaper.Optimumadsorptionanddesorptionprocessparameterswereacquiredbysystematicallystudy.ThepolymericresinNDA-107indicatedgoodadsorption&desorptionof1,2,4-acidinthewastewater.Theremovalefficiencyof1,2,4-acid,CODerisabout78%,72%respectively.Itisevidentthatthisadsorptionprocessisanefficienttreatmentmethodfor1,2,4-acidproducingwastewater.Atthesametime,theaccumulationandresourcereuseofl,2,4-acidcanberealizedinthisprocess.

简介：TiCl_4/MgCl_2/claycompoundcatalystwaspreparedbychemicalreaction.Exfoliatedpolypropylene(PP)/claynanocompositesweresynthesizedbyinsitupolymerizationwiththiscompoundcatalyst.Effectsofpolymerizationtemperature,polymerizationtime,propylenepressure,solventconsumptionandpre-treattimeofcatalystoncatalystactivityandcatalyticstereospecificitywerestudied.Underoptimalconditions,activityofthenano-compoundcatalystisabout88.3kg/(molTi·h).IsotacticityofPPobtainedinthenanocompositesisintherangeof89%-99%,anditsmeltingtemperatureisabout159℃.Theweight-averagemolecularweightofPPcanreach6.7×10~5-7.8×10~5,andthemolecularweightdistributionisbetween7.7and7.9.

简介：Polyolefinsthatbearachiralsidechain(typicallyanisobutylgroup)experienceaso-calledmacromolecularamplificationofchirality:thechiralside-chaininducesaslightpreferenceforeithertgortg-mainchainconformation.Thisslightconformationalbiasisamplifiedcooperativelyalongthechain,andresultsinpreferredchiralityofthemainchainhelicalconformations.Asaresult,thesepolymersdisplayaliquid-crystal(LC)phasebothinsolutionand,inthemeltasatransientphaseonthewaytocrystallization.Theexistenceoftwoprocesses(melt-LCandLC-crystaltransitions)resultsinunconventionalbehaviorsthatwerefirstanalyzedbyPinoandcollaboratorsbackin1975.Thesepolymersalsoofferameanstotestthestructuralconsequencesofrecentlyintroducedcrystallizationschemes.Theseschemespostulatetheformationofatransientliquid-crystalphaseasageneralschemeforpolymercrystallization.

简介：Gasphasereductionofcarbonmonoxidetoformaldehydeandethylenewasfoundinelectrochemicalcellwithaninorganicionexchangerα-Zr(HPO4)2·H2Ousedassolidproton-conductingelectrolyteatroomtemperatureandatmosphericpressure.ThetypeandamountoftheelectroreductionofCOdependonthedifferentmetalelectrodesandcurrentdensities,whichgivesalankbetweenheterogeneouscatalysisandelectrochemistry.

简介：Kineticsofchloride/sulfate,chloride/nitrateandnitrate/sulfateforwardexchangesandreverseexchangesatsolutionconcentrationsof1N,0.2Nand0.02Non201×7strongbaseanionexchangeresin,respectively,havebeenexaminedat25℃.Itisfoundthattheforwardandthereverseexchangeratesofthetwogivenionsatlowsolutionconcentration,respectively,underidenticalconditionscanbecontrolledbydifferentmechanisms,whilethoseathighsolutionconcentrationareallcontrolledbyparticlediffusion.Theternaryexchangeratesofsulfate/(chloride+nitrate)andnitrate/(chloride+sulfate)havealsobeenexamined.

简介：Dithia-monoaza18-Crown-6anditsimmobilizationproduct,silica-bound1,7-dithia-4-aza-10,13,16-trioxa-cyclooctadecaneviaaspacerofthreecarbonatoms,anditsplatinumcomplexhavebeensynthesized.Itisfoundthattheplatinumcomplexisanefficienthydrosilylationcatalystforolefins.TheXPSdataoftheplatinumcomplexarereported.

简介：Newmodelcompound1H,1′H-Bis（benz-Δ^4-imidazoline)2,2′-spiro-titaniumdichloridewaspreparedandthestructureofthecompoundwasdeterminedby1R,MSandelementaryanalysis.