简介：Fourkindsofpalladiumcatalystsdispersedonpoly-N-vinyl-2-pyrrolidonewerepreparedbyusingCH3OH-NaOH,NaBH4,H2OorCH3OH-H2Oasthereducingagentintheprocessofcatalystpreparation.ThecatalystswerecharacterizedbyXPS,TEM,XRDandusedforthehydrogenationofmethylacrylate.Itwasfoundthatthevalencestateofpalladiumanddistributionofpalladiumparticlesaswellasthehydrogenationrateweregreatlyaffectedbythereducingagent.ThebestevenlydispersedpalladiumcatalystshowinghighhydrogenationactivitywaspreparedusingCH3OH-NaOHasthereducingagent.

简介：Inthiswork,DSCandSEMstudiesindicatethation-ligandinteractioncanbeutilizedtoenhancetheinteractionofpoly(styrene-block-2-vinylpyridine)[P(S-b-2VP)]andpolyethylenebasedionomer(Surlyn).Thecompatibilityforthisblendingsystemcanbeimprovedbythisspecialinteractionand20/80wtistheoptimumblendingcompositionwithgoodcompatibility.FTIRresultsfurthercertifythatstronginteractionsexistintheblendingsystem.

简介：Polystyrenemacromonomerswithdifferentmolecularweightwerepreparedbyradicalpolymerizationofstyrene(St)inbenzeneusingβ-methacryloxylethyl2-N,N-diethyldithiocarbamylacetate(MAEDCA)asamonomer-iniferter.Characterizationofthemacromonomerby~1H-NMRshowedthattheendgroupswereα-methacrylyoxylethyloxycarbonyl-methylandω-(N,N-diethyldithiocarbamyl).Themacromonomerwasdifficulttohomopolymerize,butitwaseasilycopolymerizedwithmethylmethacrylate(MMA)initiatedbyAIBNtoformgraftcopolymers(PMMA-g-PSt)withPStbranchesrandomlydistributedalongthePMMAbackbone.CopolymerizationreactionandthestructureofthegraftcopolymerswerestronglyaffectedbyM_nandconcentrationofthemacromonomer.ThecompositionandM_nofthepurifiedgraftcopolymerweredeterminedby~1H-NMRandGPCanalysis.

简介：AnewkindofpolysiloxanecontainingN,N’-bis（diphenylsilyl）tetraphenylcyclodisilazanewaspreparedbyanionicnon-equilibriumpolymerizationwitha"seedsolution"asinitiator.Themonomer,N,N’-bis（hydroxydiphenylsilyl）-tetraphenyl-cyclodisilazane（BHPTPC）,wassynthesizedviathehydrolysisofN,N’-bis（chlorodiphenylsilyl）tetraphenyl-cyclodisilazane（BCPTPC）.AnewmethodforthepreparationofBCPTPCisalsoreportedherewithhighyieldandsimplermanipulation.ThesynthesizedpolysiloxanecontainingN,N’-bis（diphenylsilyl）tetraphenylcyclodisilazanewascharacterizedby1H-NMR,29Si-NMR,gelpermeationchromatography（GPC）andintrinsicviscosity.

简介：ThesorptionbehaviorofN-methyl-2-thio-imidazoleresin(MTIR)forRh(Ⅲ）wasinvestigated.TheoptmumsorptionconditionofMTIRforRh(Ⅲ）,sorptionratet1/2=84min,sorptioncapacity1.37mmolRh(Ⅲ）/gMTIR,[140.5mgRh(Ⅲ）/gMTIR],sorptionmolarratio0.34Rh(Ⅲ）/functionalgroup,distributioncoefficientD=2.5×10^3mg·g^-1weredetermined.ThesorptionselectivityofMTIRforRh(Ⅲ）inthepresenceofcommonmetalions,Fe^3+,Co^2+,Ni^2+andCu^2+wasexamined.Rh(Ⅲ）adsorbedonMTIRcanbeelutedquantitativelybyusingamixedsolutioncomposedof20%thio-urea-acetone:6molHCl.dm^-3(1:1vol.)usedasaneluent.Rh(Ⅲ）canbeseparatedfromthemixtureofRh(Ⅲ）andFe^3+,Co^2+,Ni^2+,Cu^2+byusingD72resinandMTIRsuccessively.

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简介：N-acetyl-D-methionine,NaAcandtheremainsofN-acetyl-L-methioninedramaticallyaffectthepurificationofL-methioninewhenpurifiedfromthemixtureofenzymaticallydeacylatedN-acetyl-DL-methionine,leadingtoalowyieldconventionally.Here,thispaperreportsasuccessfulseparationandpurificationofbothL-methionineandN-acetyl-D-methioninebyanHion-exchangecolumn.ThepH,L-Metconcentrationandtheratiobetweenthecontentofsodiumcationandtheion-exchangecapacitywereoptimizedtoobtainthemaximumyield.Experimentalresultsindicatethat,undertheoptimizedconditions,theyieldsofL-methionineandN-acetyl-D-methioninecanreachashighas85%and75%,respectively.

简介：N-nitrosaminesarestrongcarcinogensforhumans.Thispapergivesanoverviewofthenitrosmainesincigarettesmokeincludingtheformation,theharmfulness,theanalyticalmethodsofthenitrosmainesandtheadsorptionsanddegradationsofN-nitrosamines.

简介：Bythereactionofpoly(bromoacetylstyrene)(EBPS)withthiaurea(TU),akindofnovelchelatingresinwithheterocyaclicringofsulfurandnitrogen,poly[4-(2-amino)thiazoleyl-4-vinylben=ene],wassynthesized.ItsstructurewascharacterizedbyFTIRandelementalanalysis.Thefactorswhichhaveinfluenceonthereactionsuchasreactiontime,solvents,andmolarratioofreactantswereinvestigated.

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

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简介：Inthispaper,sixkindsofactivatedcarbonssuchasAg^+-activatedcarbon,Cu^2+activatedcarbon,Fe^3+-activatedcarbon,activatedcarbon,Ba^2+-activatedcarbonandCa^2+activatedcarbonwereprepared.Themodelforestimatingactivatedenergyofdesorptionwasestablished.Temperature-programmeddesorption(TPD)experimentswereconductedtomeasuretheTPDcurvesofn-hexanolandthenestimatetheactivationenergyfordesorptionofn-hexanolontheactivatedcarbons.Resultsshowedthattheactivationenergyforthedesorptionofn-hexanolontheAg^+-activatedcarbon,theCu^2+-activatedcarbonandtheFe^3+-activatedcarbonwerehigherthanthoseofn-hexanolontheactivatedcarbon,theCa^2+-activatedcarbonandtheBa^2+-activatedcarbon.

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简介：Animprovedmethodisdevelopedbyusingstronglyacidiccationexchangeresin(001×1，H^+form)asacatalystforthesynthesisofdiphenyl1-(N-benzyloxycarbonyl-amino)alkanephosphonatesand1-(N-benzyloxycarbonylamino)alkanephenylphosphinicacidsinhighyields.