简介:Silicawasused,asacatalystcarrier,toloadceroussulfateforcatalyzingthesynthesisofn-butylacetate.Themainpurposeofthisresearchwastoexplorethefeasibilityofsilicainimprovingthedecentralityandactivityofthecatalyst.Theeffectsofmolarratioofbutylalcoholtoaceticacid,theceroussulfateloadingsandthereactiontimeontheconversionofaceticacidwerestudiedbysinglefactorexperimentmethodandorthogonalexperimentmethodrespectively.Therefractiveindex(n20D)andmolecularstructureofthepreparedn-butylacetateweremeasuredbyAbbeRaefractometerandFourierTransformInfraredspectroscope,respectively.Thecomparisonsofthesilicaloadedandunloadedcatalystsforcatalyzingthesynthesisofn-butylacetateweremade.Theresultsshowedthatthesuitableconditionsforsynthesizingn-butylacetatewere:molarratioofbutylalcoholtoaceticacidof1.4∶1,uselevelofloadedceroussulfateof0.30gandreactiontimeof50min,respectively.Themaximumconversionofaceticacidforthesilicaloadedcatalystreached98.62%whichwas12.32%and16.43%higherthanthosefortheunloadedcatalystsreportedinliteratures,buttheuselevelofceroussulfatefortheformerwasmuchlessthanthoseforthelattersundersimilaroptimaltechnicalconditions.Thesilicawasprovedtobeagoodcatalystcarrierforenhancingdecentralityandactivityofthecatalystandincreasingtheconversionofaceticacid.Therepentanceofthesilicaloadedceroussulfatewasalsoinvestigatedintheexperiment.
简介:Di-n-butylphthalate(DBP)是有潜力影响男复制的内分泌破坏的化学药品。然而,低剂量的DBP的繁殖效果仍然不是众所周知的,特别在分子的水平。在现在的学习,pubertal男性Sprague-Dawley老鼠是在大量剂量的口头上地管理的DBP(0.1,1.0,10,100和500 ;为30天的mgkg−1天−1)。选择结束点包括了繁殖机关重量,阴囊的组织病理学说和浆液神经质的层次。另外,proteomic分析被执行识别是在低剂量由于暴露表示到DBP的差别的蛋白质(0.1,1.0和10 ;mgkg−1天−1)。有毒的效果在高剂量的组被观察,包括睾丸和epididymides的异常开发,生精的小管,精子发生的损失和浆液荷尔蒙的反常层次的严重萎缩。有DBP的低剂量的处理似乎施加‘;浆液荷尔蒙上的刺激effect'。老鼠睾丸的Proteomics分析证明20差别表示了蛋白质。(SOD1)在这些蛋白质,在HnRNPA2/B1的表示的改变,vimentin和superoxidedismutase之中,1被西方的污点和immunohistochemistry进一步证实。一起拿,我们断定DBP的高剂量导致了阴囊的毒性,并且DBP的低剂量在在Sertoli和Leydig房间的数字和功能象变化一样涉及精子发生的蛋白质的表示导致了变化,尽管没有明显的词法变化出现了。这些差别的鉴定表示了蛋白质关于在雄的老鼠复制上位于DBP的效果下面的机制提供重要信息。
简介:Eightnovelcompoundshavebeensynthesizedandtheyaretwoseriesofmixedtri(butyl/cyclohexyl)tincarboxylates:BunCy3-nSnO2CR(n=1,2;R=n-C3H7,C6H5,4-ClC6H4,4-NO2C6H4).InadditiontothestudiesoftheirstructureswithIR,119Snand13CNMR,wetestedtheirfungicidal,insec-ticidalandacaricidalactivities.Thepercentageofinhibitiontotheaforementionedphytopathogenisabout80—100%at50ppminglasshouseand100%forT.Uriticaeat500ppm.Thosefindingsindicatethatthiskindofcompoundshavebothfungicidalandacaricidalactivitiesandmayhaveagoodprospectforapplications.
简介:Diblockcopolymerscontainingpolystyrene(PSt)andpolybutylmethacrylate(PBMA)segmentsandrandomcopolymerofstyrene(St)andbutylmethacrylate(BMA)havebeenpreparedbyatomtransferradicalpolymerization(ATRP).DiblockcopolymersofBMAandStwithpredeterminedmolecularweight(1×10^4-6.5×10^4)andnarrowermolecularweightdistribution(1.25-1.5)wereobtained.Therandomcopolymercompositionsweredeterminedby^1HNMRspectroscopyandthereactivityratioswereevaluatedbytheextendedKelen-TudosmethodtobeYSt=0.91,YBMA=0.32.
简介:OpticallypureL-butyllactatewassynthesizedbynormaltransesterificationusingnafion-Hcatalystinmoderateyield.Variousreactionconditionswereinvestigated,includingthereactiontemperature,reactiontime,ratioofthestartingmaterialandamountofthenafioncatalyst.
简介:<正>现代汉语中,“不”字不能和体词性成分组合。不过前后同形的体词性成分之间可以加“不”字构成“N不N”格式。例如:(1)这关头,还有什么集体不集体!只能靠各自的直觉判断。(《十月》1984年第6期)(2)右派不右派与我什么相干!反右时我象海边远远一个小石子,浪花也没溅到我身上。(《小说选刊》1985年第6期)(3)甚么酒馆不酒馆,滚它的。(《契诃夫小说选》P43)(4)朱老忠说:“老英雄不老英雄,反正退回十几年去,有三五个人,走不到咱跟前。(梁斌《红旗谱》P304)本文从语法、语义、语用三个角度,粗略地分析“N不N”格式的特点。一“N不N”格式,根据一定的形式特征可以分为两大类:一类是多项“N不N”并列的形式,我们叫做A类;另一类是只有一项“N不N”的形式,我们叫做B类。我们先讨论A
简介:Averymildandextremelyefficienthydrolysismethodfortransformationofpolystyrene-b-poly(tert-butylacrylate)(PS-b-PtBA)topolystyrene-b-poly(acrylicacid)(PS-b-PAA)wasdesignedandcarriedoutusingmoreconvenientandinexpensivechlorotrimethylsilane/sodiumiodideasreagents.Thehydrolysisproductcanself-assembleinaqueousmediatogiveregularmicelleswithPSblockformingthecoreandPAL4blockformingthecorona,orintetrahydrofuran(THF)togivereversemicelleswiththehydrophilicblockinthecore.
简介:Thesemibatchemulsifier-freeemulsioncopolymerizationofmethylmethacrylate(MMA)andbutylacrylate(BA)inthepresenceof2-hydroxyethylmethacrylate(HEMA)initiatedbyK2S2O8(PSP)wasstudied.Thelatexparticlescanmaintainanappreciablestabilityduringtheemulsifier-freeemulsioncopolymerizationofMMAandBAinthepresenceofHEMA.Theaverageparticlediameterincreasewithanincreaseoftotalsolidscontent,HEMAcontent,PSPcontent,ionicstrengthofthesystemandmonomerfeedrate,anddecreasewiththemonomerfeedrationfrom3/1(MMA/BA:molarration).to1/3.ThestabilityofthisreactionsystemisimprovedbyaddingHEMAasnonioniccomonomer,Highsolidscontent(50%)latexwithmonodisperseparticlecanbeobtainedusingthisprocess.
简介:ThesynthesisandphosphorescencepropertiesoftwonovelIr(Ⅲ)complexesbearingtert-butylsubstituents,bis(4-tert-butyl-2-phenylbenzothiozolato-N,C2′)iridium(Ⅲ)(acetylacetonate)[(tbt)2Ir(acac)]andbis(4-tert-butyl-1-phenyl-1H-benzimidazolato-N,C2′)iridium(Ⅲ)(acetylacetonate)[(tpbi)2Ir(acac)],arereported,theirmolecularstructuresareconfirmedby1HNMR,ESI-MSandelementaryanalysis.Photoluminescence(PL)studiesrevealedthattheycanemitstronggreenandorangephosphorescenceinhighquantumyields.Comparedtotheirprototypeslackingoftert-butylsubstituents,thetwonoveliridium(Ⅲ)complexesbothhaveshorterlifetimesandimprovedornearlysimilarPLquantumefficiencies,implyingthattheexcitonquenchingisinhibitedeffectivelywhenmolecularsterichindranceincreases.Thetwochelateshavegreatpotentialtobeusedaselectrophosphorescentmaterials.
简介:Cationic乳胶与cationic表面活化剂通过苯乙烯(圣)和丁基acrylate(BA)的乳剂copolymerization被准备,cetyltrimethyl铵溴化物(CTAB)。包括粒子尺寸,乳胶性质缩放分发,潜力,表面紧张和单体变换,为与不同CTAB数量准备的乳胶被决定。这些性质的进化在乳剂聚合期间被跟随以便理解粒子形成的机制。结果证明粒子尺寸和潜力是聚合时间和乳胶固体的功能。有cationic的平行乳剂聚合,anionic控告了开始者,没有费用的开始者也被执行,乳胶性质在不同聚合时间被决定。所有这些结果专心地基于乳剂聚合,表面活化剂吸附和乳胶粒子稳定的机制被解释。