简介：Alginate-Cu(Ⅱ）complexbeadsormembraneswerepreparedforremovalofurea.ThemechanismofsorptionofureawasidentifiedbyUV-Visiblespectra,FT-IRspectraandFar-Infraredspectra.Thefactorsaffectingtheureasorptioncapacitywerediscussedindetail.ResultsshowedthattheAlginate-Cu(Ⅱ）complexsorbentcansorbabout60myureapergramofsorbentat37℃andtheconcentrationofureawas130mg/100mlinNa2HPO4andNaH2PO4buffersolution(pH=7.0).

简介：PLAispresentlyconsideredasthemostattractivecompoundfortemporarytherapeuticapplicationinthebiomedicalfield.Inthispaperwegiveanoverviewofthepresentknowledgeonthedegradationbehavior,processingtechnologyofPLAanditsapplicationinthefixationofbonefracture.

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简介：Thisstudyisconcernedwithchitosan-polyacrylicacidcomplexasacarriertoimmobilizeglucoseoxidase(GOD)andcellulase.TheoptimumemperatureoftheimmobilizedGOD(IG)wasdeterminedtobe60℃whichishigherthanthatofthenativeGODabout40℃.Theoptimumtemperatureoftheimmobilizedcellulase(IC)wasdeterminedtobeabout30℃higherthanthatofnativecellulase.BothoftheoptimumpHofIGandICshiftedonepHunittoacid.ImmobilizedenzymemaybeusedinmorewidepHrange.Theirstoragelifearemuchlongercomparedwiththeirnativestates.Bothofthemcanbereusedatleast12times.

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

简介：Anewcoupledfiniteelementformulationisproposedtocalculateaconformationtensormodelintwocomplexflows:aplanarcontractionflowandaplanarflowaroundasymmetricallyplacedcylinder.Thecomponentsofconformationtensorarefirstcomputedtogetherwiththevelocityandpressuretodescribethechangeofmorphologyofpolymerchaincoilsinflowfields.Macroscopicquantitiesofviscoelasticflowarethencalculatedbasedontheconformationtensor.Comparisonsbetweenthenumericalsimulationsandexperimentsforstresspatternsandvelocityprofilesarecarriedouttoprovethevalidityofthemethod.

简介：AhighMwofPLLAwassynthesized,itintendedtobeusedinthemanufactureofbioabsorbablescrewappliedinbonefractureinternalfixation.Theopticalreactionconditionshavebeendiscussed.

简介：Thestereoregularpolymerizationofmethylmethacrylate(MMA)havebeeninvestigatedwithchiralanioniccomplexinitiator[FILi-(-)SP]intoluene,THFandtoluene/THF[1/1(v/v)].ThetacticitiesofPMMAsobtainedinthethreesolventshavebeenfoundtobemainlyasyndiotactictriads(s-PMMA)withcontentof72.3,67.7and71.4%,respectively.

简介：Silica-bound15-Crown-5,18-Crown-6withaspacerofpropyloxymethylandtheirplatinumcomplexeshavebeensynthesized.Itwasfoundthattheywereefficientcatalystsforthehydrosilylationofolefmswithtriethoxysilaneinthetemperaturerangeof60to130℃.

简介：Polymerboundpalladium(Pd)complexcatalystswithgraftingacrylonitrileoninorganiccompound(MgO,Y-molecularsieveandSiO2)bypre-radiationmethodwerestudies.Thepalladium-graftingpolymershavebeeninvestigatedbyX-rayphotoelectronspectrscopy(XPS).ItisindicatedthatpeakwidthofC1sandO1sspectraofMgO-g-PAN-Pd(radiation-inducedgraft)iswiderthanthatofMgO-PAN-Pd(chemicalmethod)andPeaknumbersofformerareonemorethanlater.Accordingtothereportinreference,thispeakisattributedto-O-Cgroup.Thus,thegraftacrylonitrileonMgOmaycompletethroughoxygenatomsimMgOandβ-carbonatomsinacrylonitrile.Thepolymercatalystobtainedbyradiationgraftingisahigheractivehydrogenationcatalystforolefinesandbetterantioxicthanthatofoneobtainedbychemicalmethod,andithasselectivityforhydrogenationcatalyst.

简介：Thecompositeofα-ZrPandfumedsilicawaspreparedbydispersingpredeterminedmolarratiosofpolycrystallineα-ZrPinwater.Admittancemeasurementofthesampleswasmadeinthefrequencerangefrom5Hzto1MHzandthetemperaturerangefrom-20℃to20℃.Theactivationenergyinconductionofthecomposites,withdifferentmolarfractionofα-ZrP,isabout5.9KJ/molat60%and40%relativehumidities.Theresultsshowthatthechargetransportmechanismwasnotchangedaftermixingfumedsilicaintoα-ZrPandthechargetransportmediumiswaterinα-ZrPandthecomposites.

简介：Silica-boundmercaptoselenaether-containingsilsesquioxaneanditsplat-inumorrhodiumcomplexweresynthesizedfromγ-(2,3-epithiopropyl)propyltrimethoxysi-laneviaring-openingreactionwithbis(2-hydroxyethyl)sclenide,followedbyhydrolysisandimmobilizationonfumedsilica,andthenreactingwithpotassiumchloroplatiniteorrhodiumchlorideinacetoneundernitrogenatmosphere.Itwasfoundthattwonoblemetalcomplexescancatalyzethehydrosilylationofolefinswithtriethoxysilaneeffectively.Theinfluencesoftemperature,theamountofcomplexused,thenatureofolefinoncatalyticactivitywereinvestigated.

简介：Acrylateterpolymer-boundSe,Nbidentateligandwassynthesizedfromthesidechainchlorineofcopolymerandβ-dimethylamino-β′-hydroxyl-diethylselenoether.Thepolymer-supportedplatinumcomplexexhibitedhighcatalyticactivityinthehydrosilylationofolefinswithtriethoxysilane.

简介：Anewtypeofseleniouspolymer,silica-boundpolybispropoxyethyl-selenidesilsesquioxane,anditsplatinumcomplexweresynthesizedfrombis-allyloxyethylselenideviahydrosily-lationwithtriethoxysilane,followedbyimmobilizedonfumedsilica,andthenreactingwithpotassiumchloroplatiniteundernitrogenatmosphereinacetone.Itwasfoundthattheplatinumcomplexcancatalyzethehydrosilylationofolefinswithtriethoxysilaneeffec-tivelyTheeffectsofthenatureofthesubstrate,theamountofcomplexused,andthereactiontemperatureonthecatalyticactivitywereinvestigated.

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简介：5-Chloromethyl-2-norbornenewassynthesizedviaDiels-Alderreactionofcyclopentadieneandallylchlorideusingapolymersupportedborontrifluorideasthecatalyst,andwasthenlithiatedandusedtoinitiatealivinganionicpolymerizationofstyrenetoprepareamacromonome,5-polystyryl-2-norborneneNB-PS.CombgraftcopolymerPNB-g-PSwassynthesizedviaringopeningmetathesispolymerizationofthemacromonomerunderthecatalysisofrutheniumcarbenecomplexRuCl2(PPhg2(=CCHtBu)anditspolymersupportedcorrespondent.Experimentalresultsshowedthatthebehaviorofboththesupportedboronandsupportedrutheniumcatalystsaresuperiortotheirunsupportedcounterparts.Thepossiblepromotionmechanismofthetailor-madesupportsisdiscussed.

简介：Threenewpolysesquisiloxane-boundplatinumcomplexesweresynthesizedviahydrolysisofN,N-di(β-ethylmercaptoethyl)γ-(triethoxysilyl)propylamineorcohydrolysisofthemonomerwithdodecyltriethoxysilaneorwithphenylpropylthiethoxysilaneandimmobilixationonfumedsilica,followedbyreactingwithpotassiumplatiniteinacetoneunderargonatmosphere.Theplatinumcomplexesexhibitedhighcatalyticactivityforthehydrosilylationofolefinsbytriethoxysilane.Theeffectsoftemperatureandtheamountofcomplexonthecatalyticactivity,aswellastherecoveryandreusabilityofthecatalystswereinvestigated.

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