学科分类
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11 个结果
  • 简介:Theinfluencesofsilicavolumefraction,electrolyteconcentrationandpHvalueuponthestressdependenceofelasticmodulusG′andviscousmodulusG″wereinvestigated.Theresultsshowthatthesuspensiontransformsfromaliquid-likestatetoasolid-likestatewithincreasingthevolumefractionofsilica.Suchasolid-likestatecanbetransformedbackintoaliquid-likestateundertheapplicationofalargerstress.Atthehighervolumefraction,thelargercriticalstressisrequiredtoinducethetransitionfromsolid-liketoliquid-likestate.AstheelectrolyteconcentrationdecreasesorpHvalueincreases,theinter-particleforceincreases,whichcausesthestatetransitiontooccuratahigherstress.

  • 标签: 状态转移 固态 液态 二氧化硅 悬浮液 电解液浓度
  • 简介:Sphere-likecompoundC8H17Si(OPhC12H25)3N(1)formsmesophases.Inordertoinvestigatetherelationshipbetweenmolecularstructureandliquidcrystalproperties,structuralstudiesarecarriedoutonthemodelmoleculesofcompound1anditssubstitutedderivativesusingahinitiocalculations.TheresultsshowthatthecyanoorchlorosubstitutedtribenzosilatranecompoundsR1Si(OPhR2)3N(R1R2=CNorCl)havemuchbiggerdipolemomentsoranisotropyofpolarizabilityandmorelikespherethanthecorrespondingalkylsubstitutedcompounds.Cyanoorchlorosubstitutedtribenzosilatraneswouldbebettercandidatesforsphere-likemeso-gens.

  • 标签: Sphere-like MESOGEN tribenzeosilatrane ab INITIO CALCULATION
  • 简介:纸从superhydrophobic模板和superhydrophilic底层的联合效果由三明治结构为像杆的硅石粒子的面向的汇编表明了一条灵巧的途径。像杆的粒子能被安排在似环,像平方并且等等从限制了模板的效果,它将为各向异性的粒子的面向的汇编和新奇功能的材料和设备的开发生产重要卓见。

  • 标签: 各向异性的粒子 像杆的硅石 帮助模板 自己组装 模式
  • 简介:Synthesisofinorganicnanostructureswithspecificsizeandwelldefinedmorphologieshasattractedconsiderableattentionduetotheirsuperiorelectrical,optical,magnetic,andchemical

  • 标签: 纳米结构 FE2O3 合成 笼状 自由 三维
  • 简介:以Worm-like介孔分子筛为载体,通过浸渍的方法将磷钨钼酸负载到分子筛的孔道内,制备负载型磷钨钼酸催化剂,并采用XRD、N2-吸附脱附、红外光谱等方法对负载型催化剂进行表征.将负载型磷钨钼酸催化剂应用于乙酸异戊酯合成反应,考察乙酸与异戊醇物质的量比、反应时间、环己烷用量、负载型催化剂用量及磷钨钼酸负载量等因素对酯化率的影响和负载型催化剂的重复使用性能.结果表明,用负载型磷钨钼酸催化剂催化合成乙酸异戊酯的效果很好,酯化率可达92.8%,且负载型催化剂的重复使用性良好.

  • 标签: 负载 磷钨钼酸 乙酸异戊酯 催化剂
  • 简介:Anovelgel-likeprocesshasbeendevelopedforsynthesizingLiaNi0.8Co0.2O2powders,usingcitricacidasachelatingagent.Thisprocessimprovesthehomogeneityofconstituentcationandenhancestheirreactivityintheobtainedprecursor.Theresultsofelectrochemicaltestdemonstratedthatthesematerialsexhibitedexcellentelectrochemicalproperties.Itsinitialcapacityreached181.6mAh/gandreversibleefficiencyatthefirstcycleisabout88.6%.

  • 标签: 凝胶体 合成 亚微细粒 LiaNi0.8Co0.2O2 应用 粉末
  • 简介:Anovelflower-likehydratedmagnesiumcarbonatehydroxide,Mg_5(CO_3)_4(OH)_2·4H_2O,withmicro-structurecomposedofindividualthinnano-sheetswassynthesizedusingafacilesolutionroutewithouttheuseoftemplateororganicsurfactant.Reactiontimehasanimportanteffectonthefinalmorphologyoftheproduct.Themicro-structureandmorphologyofMg_5(CO_3)_4(OH)_2·4H_2OwerecharacterizedbymeansofX-raydiffractometry(XRD),field-emissionscanningelectronmicroscopy(FE-SEM).Brunauer-Emmett-Teller(BET)surfaceareasofthesampleswerealsomeasured.Theprobableformationmechanismofflower-likemicro-structurewasdiscussed.ItwasfoundthatMg_5(CO_3)_4(OH)_2·4H_2Owithflower-likemicro-structurewasanovelandefficientcatalystforthesynthesisofdiphenylcarbonate(DPC)bytransesterificationofdimethylcarbonate(DMC)withphenol.

  • 标签: 碳酸镁氢氧化 合成 微观结构 催化活性 酯交换反应