简介:Theabsorptionoffreealkaliatlowconcentrationbysubacidresinwastracedwithelectricconductancemethod,theeffectoftemperatureontheadsorption,theactivationenergy,ofadsorption(Ea)andinteractionenergy(U)wasstudied.Theresultshowedthat,theprocessoflowconcentrationalkaliadsorptionbysubacidresinwasinaccordancewithmechanismofmonomolecularlayerabsorption,inaddition)withtheincreasingoftemperature,theinteractionenergybetweenadsorbateandsorbentincrease,sodidthesurfaceadsorptionrate(k),andlinearcorrelationexistedbetweeninteractionenergy(U)andtemperature(T).
简介:Thesurfaceofpolypropylene(PP)membranewasmodifiedbylowtemperatureplasmawithammonia.Theeffectofexposuretimewasinvestigatedbymeansofcontactanglemeasurement.Theresultsshowthatlowtemperatureammoniaplcsmatreatmentcanenhanceitshydrophilicity.Chinesehamsterovary(CHO)cellsattachmentonthemodifiedmembranewasenhancedandthegrowthrateonthemembranewasfasterthanunmodifiedone.
简介:Fournewlow-band-gapalternatingcopolymers(P-1,P-2,P-3andP-4)basedonelectron-richbenzodithiopheneandnewlydevelopedelectron-deficientunits,thienopyrazineordithiadiazatrindenederivatives,weresynthesizedbyStillepolycondensation.Allpolymersexhibitgoodsolubilityincommonorganicsolventsandabroadabsorptionbandinthevisibletonear-infraredregions.Thefilmopticalbandgapsofthepolymersareintherangeof1.28-2.07eVandthehighestoccupiedmolecularorbital(HOMO)energylevelsareintherangeof-4.99eVto-5.28eV.Bulkheterojunctionpolymersolarcells(PSCs)ofthepolymerswerefabricatedwithphenyl-C61-butyricacidmethylester(PC61BM)asacceptormaterial,andapowerconversionefficiencyof0.80%wasrealizedwithP-1asdonormaterial.
简介:Inviewoftheimportanceofdispersionagent,theamountofthecrosslinkingmonomerandthediluentinsuspensionpolymerizationfortheproductionofparticlesizenarrowlydistributedlow-densitystryenedivinylbenzenecopolymermicrobeads(LDPS),theiractionsarepreliminarilyinvestigatedinthispaper.Experimentalresultsindicatethatwhenboththegelatineandpolyvinylalcohol(PVA)areuseddispersionagents,thebettereffectisachieved,DVBishelpfultotheformationofthelowerdensityfineparticles,theproportionoftheDVB/Stshouldbebetween1:1-1.5:1.Comparedwithtoluene,gasolineisthemoreeffectivediluentfortheabovetarget.
简介:Nano-SiO2或哞3被介绍给橡胶(EVA/NBR)混合包含镁氢氧化物(MH)和红磷(RP)进一步改进机械性质的乙烯乙烯基acetate/nitrile丁二烯,油抵抗,吸抑制和火焰retardancy。结果显示张力的力量和油抵抗被合并nano-SiO显著地改进<潜水艇class=“a-plus-plus”>2。为EVA/NBR混合样品的烟抑制测试两个都显示出那nano-SiO<潜水艇class=“a-plus-plus”>2和哞<潜水艇class=“a-plus-plus”>3能显著地减少烟版本数量。易燃的描述显示有33.0的LOI价值的混合样品能在UL-94测试完成V-0水平。锥热量测定测试数据证明山峰热版本率是67%比那低为纯EVA/NBR。热分析证明两nano-SiO的存在<潜水艇class=“a-plus-plus”>2和哞<潜水艇class=“a-plus-plus”>3对支持EVA/NBR混合的字符形成有益。字符剩余分析建议了那哞<潜水艇class=“a-plus-plus”>在燃烧期间在稳固的阶段聚集的3。
简介:Thestraininducedcrystallizationbehaviourinpolyimidefrom1,4-bis(3’,4’-dicarboxyphenoxy)benzeneand4,4’-oxydianiline(PEI-E)hasbeeninvestigatedbyWAXD,DSCandFTIR.TheresultsobtainedshowthatcrystallizationinPEI-Edidtakeplacejustaftertensileyielding.Meanwhile,theeffectofstraininducedcrystallizationonthethermomechanicalpropertieswasstudiedbyDMAandTMA,theresultsofwhichindicatethatthecrystallizationandhotstretchinghaveacertaininfluenceonthedynamicmechanicalproperties,suchasweakeningtheβrelaxationanddecreasingtheglasstransitiontemperature.TheTMAresultsconfirmtheshiftingofglasstransitiontemperaturetolowertemperatureregionafterhotstretching.ThisphenomenoncouldbewellexplainedbytheeffectofresidualstressaccordingtoEyring’stheory.
简介:ThewastewaterfromnaphtholAs-EproductionprocesswastreatedwithmacroporouspolymericadsorbentNDA-222.NaphtholAs-Eand2,3-acidinthewastewatercouldberemovedcompletelyandtheTotalOrganicCarbon(TOC)ofthewastewaterwasdecreasedmorethan98%from1655mg/Ltolessthan30mg/L.TheadsorbatescouldbedesorbedcompletelywithNaOHaqueoussolution.
简介:Carbazole-basedbi-functionalphotorefractivepolyacrylateswerepreparedviafreeradicalpolymerizationandpost-azo-couplingreaction.ThestructureofpolymerswascharacterizedbyFouriertransforminfraredspectroscopy(FTIR)andprotonnuclearmagneticresonance(1H-NMR)spectroscopy.Thedifferentialscanningcalorimetry(DSC)andthethermalgravimetricanalysis(TGA)wereusedtocharacterizethethermalpropertyofpolymers.Theresultsindicatethatthoughtheglasstransitiontemperature(Tg)ofpolymersincreaseswithincreasingtheratioofNLOgroups,thepolymerswithdifferentratiosofNLOgroupsstillallshowlowglasstransitiontemperaturesaround60°C,andgoodthermalstability,whicharefavorabletothepracticalapplicationofthesepolymers.Thegelpermeationchromatographic(GPC)resultindicatesthatthesepolymersallhavehigh-molecular-weightwhichisfavorabletothelongtermstabilityofthematerial.Further,thesepolymershavegoodsolubilityinchloroformsolvent,andthesolutionscaneasilybefabricatedintoopticallytransparentfilms.Gaincoefficientsof75cm-1,185cm-1and66cm-1canbeobservedatzeroexternalelectricfieldwithoutanyadditionagentorpre-polingforpolymersP-2,P-3andP-4respectively.ThedifferentcontentsofNLOgroupsresultinthedifferentpropertiesofpolymersP-2,P-3andP-4.
简介:EscherichiacoliL-asparaginasewasmodifiedwithO-car-boxymethylatedchitosanusingglutaraldehydeasacouplingagent.Theresultingcoujugateretainedmorethan50%ofitsoriginalenzymeactivityundertheprotectionofitsnormalsubstrateorproductandshowedmarkedresistancetoproteolysisbytrypsinandchymotrypsin.
简介:一系列新奇低乐队差距施主领受人(D-A)类型在主要的链(M1)并且在由电子缺乏的领受人块组成的器官的共聚物(BT-F-TPA,BT-CZ-TPA和BT-SI-TPA)悬挂(M2)是与不同电子富人一起的polymerized施主(M3M5)块,即,9,9-dihexyl-9H-fluorene,N-alkyl-2,7-carbazole,和2,6-dithinosilole,分别地经由铃木方法。这些聚合物展出了相对低的乐队差距(1.651.88eV)和宽广吸收范围(680740nm)。作为电子施主合并这些聚合物的体积异质接面(BHJ)太阳能电池,相配与[6,6]-phenyl-C61-butyric酸甲基酉旨(PC61BM)或[6,6]-phenyl-C71-butyric酸甲基酉旨(PC71BM)作为在不同重量的电子领受人,比率下面被制作并且测试与白光的照明的AM1.5的100mW/cm2。包含施主BT-SI-TPA和领受人PC71在1:2重量比率的BM显示出1.88%的最好的力量变换效率(PCE)值,与开的电路电压(Voc)=0.75V,短路电流密度(Jsc)=7.60妈/厘米2,并且充满因素(FF)=33.0%。
简介:Insitucompatibilizationoflowdensitypolyehylene(LDPE)(30%)andnylon-6(70%)blendsthroughone-stepreactiveextrusionusingt-BuOOHasaninitiatorandlowmolec-ularweightinterfacialagentsascompatibilizerswasstudied.Thecompatibilizercontainedalongchainbydrocarbon,doublebondandtwopolarfunctionalgroupswhichwascapableofreactingwithbothLDPEandnylon-6inthepresenceofinitiatortoformacopolymerattheinterfaceofthetwopolymerphases.Theextrudedblendsexhibitedsignificanten-hancementintheircompatibilitybasedonmorphological,thermalanalysisandmechanicalstudies.Theeffectofthehydrocarbonchainlengthandstructureofthefunctionalgroupofthecompatibilizerwasalsoexamined.Itwasfoundthatblendspreparedbyusingthecompatibilizercontaininglongerhydrocarbonchainandamidegrouphadbettermechanicalproperties.
简介:Theeffectofsinteringdispersedandbulk,lowmolecularweight(Mn=50,000Da),nano-emulsionpolytetrafluoroethylene(PTFE)particlesneartheirmeltingpointisdescribed.Withthenascentparticlesconsistingofca.75nmdiameter,hexagonal,singlecrystals,sinteringat,e.g.,350℃,results,initially,inmergerofneighboringparticles,followedbyindividualmolecularmotiononthesubstrateandtheformationoffoldedchain,lamellarsinglecrystalsandspherulites,andon-edgeribbons.Itissuggestedthesestructuresdevelop,withtime,inthemesomorphic'melt'.Sinteringofthebulkresinyieldsextendedchain,bandstructures,aswellasfoldedchainlamellae;end-surfacetoend-surfacemerger,possiblybyend-to-endpolymerization,occurswithincreasingtime.
简介:Theadsorptionoflowconcentrationoffreeacidbyregenerablechitinisfollowedbyelectricconductancedetermination.Theeffectofacidconcentratioin,contentoffunctioinalaminogroups,andionicstrengthonadsorptionwasdiscussed.Experimentalresultsindicatethattheactivecentreofregenerablechitinisthefreeaminogroupsonistsurface,andthattherateofadsorptionoffreeacidwasfoundtobeaffectedbytwofactors:theinteractionbetweentheadsorbentandtheadsorbateinsolutionandthatbetweentheadsorbatemoleculesorionsinsolution.