简介:Carbonnanotubes(CNTs)weresyntecizedbycatalyticchemicalvapositionandusingthealkali-reducingprereatedhydrogenstoragealloy(MINI4.0Co0.6AI0.4)powderasacatlystIwasfoundthastthesurfacemodificatiopofthealloywasefdf3ctivetpprovidethjecatalyicactivesitesforCNTsThecompoisteonthesurfaceoftehtreatedalloywredominantfortheferowthofCNTsThecompsitefoCNTswiththehydrogenstoragealloyhasthepotentialtobeusedasanewtypeofhydrogenstoragemarterialwithoutfurtherpurtherpurfication
简介:粉末催化剂Cu-Cr-O用于碳nanotubes(CNT)的合成的一篇小说被开发,它经由氨降水方法被准备。扫描热量计(TG-DSC)的thermo-gravimetric/differential的技术,X光检查衍射(XRD)以及扫描电子显微镜学(SEM)和传播电子显微镜学(TEM)被采用了分别地描绘热分解过程,晶体阶段和同样综合的材料的微结构的形态学。当先锋在400,500,600,和700琠慨?桴獩洠瑥潨?獩猠極慴汢?潦?牰摥捩楴杮琠敨猠牴湥瑧?景挠浯潰楳整氠浡湩瑡獥?桴?業牣浯'炭暘e牴湥瑧?桴潥祲椠?慲歮摥戠?潣灭牡湩?瑩眠瑩?污?桴?被锻烧时,结果证明碳nanotubes成功地作为催化剂用Cu-Cr-O被综合業牣?敬敶?湡?桴?敢瑳琠潷洠捡潲氭癥汥琠敨牯敩?档獯湥映潲?桴?潗汲?楗敤?楡畬敲?數'元沞
简介:OpticallypureL-butyllactatewassynthesizedbynormaltransesterificationusingnafion-Hcatalystinmoderateyield.Variousreactionconditionswereinvestigated,includingthereactiontemperature,reactiontime,ratioofthestartingmaterialandamountofthenafioncatalyst.
简介:ZSM-48zeoliteswithvariousSi/AlratioswerehydrothermallysynthesizedintheH2N(CH2)6NH2(HDA)-containingmedia.TheobtainedsampleswerehighlycrystallizedwithminormixedphasesasevidencedbyX-raypowderdiffraction(XRD).ThealkalinetreatedZSM-48zeolitesmaintaineditsstructureunderdifferentconcentrationsofNaOHaqueoussolution.Microporesremainedunchangedwhilemesoporeswithwideporesizedistributionformedafterthealkalinetreatment.Thesurfaceareaincreasedfrom228to288m2/g.TheBr?nstedacidsiteshadlittlealterationwhileanobviousincreaseofLewisacidsiteswasobserved.Thehydroisomerizationofhexadecanewasperformedasthemodelreactiontotesttheeffectsofthealkalitreatment.Theconversionofhexadecanehadalmostnochange,whichwasattributedtothepreservationoftheBr?nstedacidsites.Whilehighselectivitytoiso-hexadecanewithanimprovedisotonormalratioofalkaneswasduetothemesoporeformationandimproveddiffusivity.
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简介:CuO-CoO-MnO/SiO2nanocompositeaerogels被经由大音阶的第五音胶化过程和乙醇supercritical弄干技术作为先锋把tetraethylorthosilicate(TEOS)用作Cu,公司和Mn醋酸盐的Si来源,和水的答案准备。gelatination机制被原子磁性的回声(NMR)和X光检查光电子光谱学(XPS)调查。CuO-CoO-MnO/SiO2nanocompositeaerogels的微观结构和作文被扫描电子显微镜学(FE-SEM)的地排放描绘,传播电子显微镜学(TEM),电子散光谱学(版本)和XPS。特定的表面区域,毛孔尺寸和nanocompositeaerogels的毛孔尺寸分发被Brunauer-Emmett-Teller(赌注)方法决定。产品被煤气的层析(GC)分析。结果证明CuO-CoO-MnO/SiO2nanocompositeaerogels是多孔的,与10150nm,216nm的毛孔尺寸分布,7.68nm的一种平均毛孔尺寸,和664.4695.8m2/g的一个特定的表面区域的粒子尺寸分布。在nanocompositeaerogels的转变金属的臼齿的部分是0.71%-13.77%。这种结构是有利的不仅增加装载催化剂,而且作为cocatalysts充分利用转变金属氧化物的效果;CuO-CoO-MnO/SiO2nanocompositeaerogels能在diphenyl碳酸盐的更安全、环境友好的合成和催化作用的另外的地被用作一个新奇催化剂搬运人。
简介:Directelectrochemicalformationofhydrogenperoxide(H2O2)frompureO2andH2oncheapmetal-freeearthabundantcatalystshasemergedasthehighestatom-efficientandenvironmentallyfriendlyreactionpathwayandisthereforeofgreatinterestfromanacademicandindustrialpointofview.Veryrecently,novelmetal-freemesoporousnitrogen-dopedcarboncatalystshaveattractedlargeattentionduetotheuniquereactivityandselectivityfortheelectrochemicalhydrogenperoxideformation[1–3].Inthiswork,weprovidedeeperinsightsintotheelectrocatalyticactivity,selectivityanddurabilityofnovelmetal-freemesoporousnitrogen-dopedcarboncatalystfortheperoxideformationwithaparticularemphasisontheinfluenceofexperimentalreactionparameterssuchaspHvalueandelectrodepotentialforthreedifferentelectrolytes.Weusedtwoindependentapproachesfortheinvestigationofelectrochemicalhydrogenperoxideformation,namelyrotatingring-diskelectrode(RRDE)techniqueandphotometricUV–VIStechnique.Ourelectrochemicalandphotometricresultsclearlyrevealedaconsiderableperoxideformationactivityaswellashighcatalystdurabilityforthemetal-freenitrogen-dopedcarboncatalystmaterialinbothacidicaswellasneutralmediumatthesameelectrodepotentialunderambienttemperatureandpressure.Inaddition,theobtainedelectrochemicalreactivityandselectivityindicatethatthemechanismsfortheelectrochemicalformationanddecompositionofperoxidearestronglydependentonthepHvalueandelectrodepotential.
简介:Isotacticpoly(butene-1)(iPB)withsphericalmorphologywassynthesizedsuccessfullywithbulkprecipitationpolymerizationwithoutpost-treatmentoftheproducts.ThebulkprecipitationpolymerizationprocessmadeitpossibleforiPBtobeusedasgeneralplasticduetotheacceptabledecreasedcostcomparedwiththesolutionpolymerizationprocess.TheinfluenceofcatalystresiduesontheagingandthermalstabilityofiPBsynthesizedbybulkprecipitationpolymerizationmethodwasinvestigatedbygelpermeationchromatography,mechanicalperformancetesting,thermogravimetricanalysisandinfraredspectroscopicanalysis.CommercialiPBandthelab-madeiPBwithvariedcatalystresiduecontentswerestudied.TheresultsdemonstratedthatthecatalystresiduesplayedanimportantroleintheagingprocessoftheiPB.Apossiblemechanismofagingpromotionbycatalystresidueswasproposed.
简介:AcheapandrecyclableZnO-betazeolitewasusedascatalystforthesynthesisofbenzothiazolederivatives.Thismethodprovidesseveraladvantagessuchasenvironmentalfriendliness,shortreactiontimes,highyields,simplework-upprocedureandcatalystwassuccessfullyreusedforfourcycleswithoutsignificantlossofactivity.
简介:APt-MoO3/Ccatalyst,aimedtoeliminatetheharmfuleffectofsulfurdioxide(SCb)ontheperformanceofPtnanoparticles(NPs)forcatalysisofoxygenreductionreaction(ORR)inprotonexchangemembranefuelcells(PEMFC),isdevelopedandcharacterizedbyTEM,XRDandXPS.TheresultsrevealthatPt-MoO3/Ccatalystexhibitsnotonlyahighercatalyticactivity,butalsoabetterSO2poisoningresistanceandabetterrecoveryperformancethanthecommercialPt/Ccatalystdoes.
简介:Anewreaction-controlledphase-transfercatalystsystem,lacunaryKegginpolyoxotungstate[C7H7N(CH3)3]9PW9O34hasbeensynthesizedandusedforcatalyticepoxidationofolefinswithH2O2astheoxidant.Infraredspectrawereusedtoanalyzethebehaviorofthephasetransferofcatalyst.Inthissystem,thecatalystnotonlycanactashomogeneouscatalystbutalsoasheterogeneouscatalysttobeeasilyfilteredandreused.Theepoxidarionreactioniscleanandexhibitshighconversionandselectivityaswellasexcellentcatalyststability.
简介:先进技术成就和经济的连续生长工业副产品做了处理,再循环并且再使用严重挑战。水泥工业在这个努力被认为关键部门之一在成功地(以不掩饰,但是改善一些最后的产品的性质)吸收大数量ofs臭浪费,作为总数或作为第二等的似水泥的材料。这不仅贡献一个精力和CO_2排放仓库的创造(当通常使用了,原料被节省),而且同时减轻如此的副产品的无责任感的处理引起的尖锐环境负担。在这研究,再使用的可能性花了液体催化击碎的催化剂(FCC)作为增补cementing材料(SCM)被检验。测试的Aseries被进行,开始在描绘瞄准材料并且此后评估它混合水泥的机械性质上的凝硬性的活动和它的效果。在这调查的主要调查结果表明FCC的使用作为在水泥的矿物质混合可行,加强硅质的玻璃质的残余应该代表为构造部门的稳定的供应的信仰。