简介：AdsorptionpropertiesofL-histidineonactivecarbonwerestudiedinthepaper,whichareaffectedbythemainparameters,suchasthequantitypercentofactivecarbon,pHvalueofthesolution,thetimeofadsorptionequilibriumandadsorptiontemperature.TheresultsindicatethatadsorptionequilibriumtimeofL-hisonactivecarbonisabout80minutes.Withtheincreasingofthequantitypercentofactivecarbon,theadsorbanceofL-hisdecreasessharply,andincreaseslighterafterthat.Whenthequantitypercentofactivecarbonis10%,theadsorbancereachestheminimum.pHvalueofsolutionandextractiontemperaturehavegreataffectionontheadsorption.WhenthepHvalueishigherorlowerthanthepIofL-his,theadsorbanceissmall,evenzero.Itisproventhattheexperimentalequilibriumdatawhichareobtainedundertheconditionsof80℃andpH=1.0,arefittedwiththeFreundlichequation:q=2.5914c0.8097.TheresultscanprovidecertainreferencesinL-hisadsorptionprocessofindustrialoperation.

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简介：EscherichiacoliL-asparaginasewasmodifiedwithO-car-boxymethylatedchitosanusingglutaraldehydeasacouplingagent.Theresultingcoujugateretainedmorethan50%ofitsoriginalenzymeactivityundertheprotectionofitsnormalsubstrateorproductandshowedmarkedresistancetoproteolysisbytrypsinandchymotrypsin.

简介：AhighMwofPLLAwassynthesized,itintendedtobeusedinthemanufactureofbioabsorbablescrewappliedinbonefractureinternalfixation.Theopticalreactionconditionshavebeendiscussed.

简介：在这研究，(L减水乳酸)(PLLA)一系列monodispersed被戒指洞聚合poly综合与Schiff基础铝催化剂，并且数字一般水准的效果分子的重量(M结晶化和PLLA的融化的行为上的n)被微分扫描热量测定(DSC)和宽角度的X光检查衍射(WAXD)调查。PLLA的全部的结晶化率是M与M-dependent,>18.6kg/mol的n。另外，当PLLA的Mn是18.6kg/mol时，融化的热含量(Hm)显示出最大的价值(87.1J/g)，它是最高报导的价值到现在为止。为水晶形成从的变化的批评温度-到形式，在等温的结晶化增加的晶体与M处理n增加。在再热的过程，high-MnPLLA在主导的融化山峰以前表明了一座小exothermal山峰，相应于水晶转变从-到-form,但是low-MnPLLAdidnt表演水晶转变的山峰。这些不同结晶化和融化的行为与不同Mn。

简介：(L减水乳酸)(PLLA)Poly，/pristine蛭石nanocomposites被准备由融化掺双轴的extruder，和热、机械的性质的蛭石分散状态的详细信息和蛭石的效果系统地被学习。当装载内容不超过3wt%时，结果证明在矩阵的蛭石的分散相当好。太古的蛭石能显然在nonisothermal结晶化期间改进融化结晶化温度。两结晶化时间跨度和PLLA的spherulitic尺寸由提高PLLA的主要成核在等温的结晶化状况下面与蛭石的增加的数量减少。并且增加的蛭石能也改进张力的模量和PLLA的Izod影响力量。为PLLA上的蛭石的起核心作用的效果的内在的机制被建议是在蛭石和PLLA之间的取向附生的结晶化和特定的相互作用。

简介：Antibacterialpoly(D,L-lactide)(PDLLA)fibrousmembranesweredevelopedviaelectrospinning,followedbysurfacemodificationwhichinvolvedplasmapretreatment,UV-inducedgraftcopolymerizationof4-vinylpyridine(4VP)andquaternizationofthegraftedpyridinegroupswithhexylbromide.ThesuccessofmodificationwithquatemizedpyridiniumgroupsonthePDLLAfibrousmembraneswasascertainedbyX-rayphotoelectronspectroscopy(XPS).TheantibacterialactivitiesofthesemembraneswereassessedagainstGram-positiveStaphylococcusaureus(S.aureus)andGram-negativeEscherichiacoli(E.coli).ThePDLLAfibrousmembranesmodifiedwithquaternizedpyridiniumgroupsshowedantibacterialefficiencyagainstbothbacteriaashighas99.999%.Theresultsdemonstratedthattheantibacterialactivitywasbasedontheinteractionofthepositivechargeofpyridiniumgroupandnegativelychargedcellmembraneofbacteria,resultinginlossofmembranepermeabilityandcellleakage.

简介：稀土元素aryloxides由各种各样的烷基组代替了[行(浆)3]例如甲基，isopropyl和tertbutyl，被用作单个部件催化剂影响L减水乳酸(LLA)的戒指洞聚合。催化活动，聚合特征，聚合动力学和机制被学习。稀土元素aryloxides的催化活动被结构和烷基组的数字在苯基戒指上影响，这被发现。越强壮烷基组的电子捐赠能力，催化活动将是越多higher。代用品组的数字的增加将导致一项更高催化的活动。镧tris(2,4,6-tri-tert-butylphenolate)[La(OTTBP)3]在所有镧aryloxides之中展出最高的活动。根据1H-NMR数据，LLA聚合经由包含减水乳酸的酰氧债券的劈开的协作插入机制继续了，这被建议。关键词戒指洞聚合-L减水乳酸-稀土元素aryloxides这个工作被山西省(号码2006011069)的自然科学基础和山西省(号码2009011059-7)的关键实验室的开的基础支持。

简介：Arareearthcoordinationsystemwasfirstinvestigatedasanewtypeofcatalystforthering-openingpolymerizationofα-aminoacidN-carboxyanhydrides（NCAs）.Theresultsforthepolymerizationofγ-stearyl-α,L-glutamate（SLG）NCAusingneodymiumacetylacetonate（Nd（acac）3）-orneodymiumtris（2-ethylhexylphosphonate）(Nd(P204)3)-triethylaluminum-waterascatalystswerecomparedwiththoseusingconventionalcatalysts.Itwasfoundthatthehelicalpoly（γ-stearyl-L-glutamate）withhighmolecularweightaswellasnarrowmolecularweightdistributioncanbeobtainedinthepresenceofNd（acac）3/AlEt3-1/2H2O.ThepolymerobtainedwascharacterizedbyIRandNMRspectroscopy.

简介：Thestructureandkineticsofthecomplexformedbyhyaluronicacid(HA)andpoly(L-lysine)(PLL)werestudiedbytimeresolvedlaserlightscattering,TEM,andAFM.BecauseHAhasahydrophilicbackbone,thecomplexesformedbyHAandPLLaredifferentfromthoseformedbyoppositelychargedpolyelectrolytesbothhavinghydrophobicbackbones.Insteadofformingstrongaggregatesandevenprecipitates,thecomplexinthepresenceofexcessHAisstableinthestudiedtimeperiod.Moreimportantly,thecomplexspontaneouslyformscore-coronastructurebytherearrangementofHAchains.ThecoreiscomposedofcomplexrichofPLLandthecoronaismainlyHA.FurtheranalysisshowsthatthehydrogenbondformedbyHAcreatesabarrierhinderingthefurtherrelaxationofHAchains.Theautomaticformationofcore-coronastructurebyPLL/HAishelpfulnotonlytounderstandtherelaxationofpolyelectrolyteincomplex,butalsotodevelopdrugcarrierswithdesirableproperties.

简介：ThepreparationandcharacterizationofanimmobilizedL-glutamicdecarboxylase(GDC)werestudiedThisworkistodevelopasensitivemethodforthedeterminationofL-glutamateusinganewbiosensor,whichconsistsofanenzymecolumnreactorofGDCimmobilizedonanovelionexchangeresin(carboxymethyl-copolymerofallyldextranandN.N'-methylene-bisacrylamideCM-CADB)andionanalyzercoupledwithaCO2electrode.Theconditionsfortheenzymeimmobilizationwereoptimizedbytheparameters:buffercompositionandconcentration,adsorptionequilibrationtime,amountofenzyme,temperature,ionicstrengthandpH.ThepropertiesoftheimmobilizedenzymeonCM-CADBwerestudiedbyinvestigatingtheinitialrateoftheenzymereaction,theefffectofvariousparametersontheimmobilizedGDCactivityanditsstability.AnimmobilizedGDCenzymecolumnreactormatchedwithaflowinjectionsystem-ionanalyzercoupledwithCO2electrode-datacollectionsystemmadeuptheoriginalformoftheapparatusofbiosensorfordeterminingofL-glutamateacid.Thelimitofdetectionis1.O×1O-5M.Thelinearityresponseisintherangeof5×1O-2-5×1O-5M.Theequationoflinearregressionofthecalibrationcurveisy=43.3x+181.6(yisthemilli-voltofelectricalpotentialresponse,xisthelogarithmoftheconcentrationofthesubstrateofL-glutamateacid).Thecorrelationcoefficientequals0.99.Thecoefficientofvariationequals2.7%.

简介：Metalion-imprintedlycrosslinkedchitosanresin1andresin2werepreparedbytheuseofCu^2+andNi^2+astemplateionsandglutaraldehydeascrosslinkingagent,respectively,ThroughinvestigationontheadsorptioncapactiesandbindingconstantsforCu^2+,Ni^2+andCo^2+ionsonchitosanresins,resin1andresin2exhibittheadsorptionselectivityforthemixturesolutionof1L1Cu^2+andNi^2+ions.Theadsorptionselectivityofmetalion-imprintedresinsfortheirtemplateionsinmuchhigherthanthatofuncrosslinkedchitosanresin.

简介：TheL-proline-functionalizedpolystyrenewith1-methyldecylenespacerwassynthesizedfrom2%divinylbenzene-crosslinkedpolystyrenegelvia10-bromo-1-methyldecylpolystyreneintermediate.Aftercomplexedwithcopper(Ⅱ）ion,thepolymerwithL-prolineligandwasusedasthechiralstationaryphase(CSP)forligandexchangechromatographyofaminoacidracemates.TheresultsshowedthattheCSPpossessedpowerfulenantioselectivityandallracematesofthefifteentriedaminoacidswerecompletelyseparated.

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简介：Opticallyactive(R)-(+)-2,2’-bis(2-trifluoro-4-aminophenoxy)-1,1’-binaphthylwaspreparedfrom1,1’-bi-2-naphthol.Theopticallyactivearomaticpolyimidewasalsosuccessfullysynthesized.Thisnewpolymerhasgoodsolubility,thermalstabilityetc.Itsspecificrotationwasfoundtobe+174°,anditschiropticalpropertywasalsostudied.

简介：Thecopolymerizationsofethylenewith10-undecen-1-olhavebeeninvestigatedusingvanadiumprecatalysts,bis(imino)pyrrolylvanadium(III)complexes1-3,2,5-C4H2N(CH=NR)2VCl2(THF)2[R=C6H5(1),2,6-iPr2C6H3(2),C6F5(3)],andtheiminopyrrolylandβ-diketiminateonesforcomparison.Thepolarmonomerwaspretreatedbydiethylaluminiumchloride(presentalsoasthecocatalyst)beforethecopolymerization.ThemonomerreactivityratioswereevaluatedusingtheFineman-Rossmethod.Theligandstructureconsiderablyinfluencedthecatalyticactivityandtolerancetowardsthepolarmonomer,thepolarmonomerincorporationandthemolecularweightsoftheresultantcopolymers.Thebis(imino)pyrrolylvanadiumcomplexesexhibitedpromisingcatalyticperformanceforthecopolymerization,andahighcatalyticactivityupto3.84kg/mmolv·hwithahighcomonomerincorporationof14.0mol%wasachievedbycomplex3undermildconditions.

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

简介：Ourobjectivesweretodevelopanewchemicalmethodforthepolymerizationofpyrrole.CuCl2dissolvedinC2H5OHsolventisprimarilyusedfortheinitiationpolymerizationofpyrrole.ThepolymerswithdifferentyieldandconductivitywereobtainedbyraringtheinitialconcentrationofCu2+.TheinitialconcentrationsofCu2+variedfrom1.2×10-4moleto6.48×10-3moleCu2+with2.16×10-2molepyrrole.Thepolypyrroleobtainedwascharacterizedwithelementalanalyzer,XPS,IRspectroscopy,Four-pointprobeandSEM.