学科分类
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23 个结果
  • 简介:Theactivityofα-amylasefromporcinepancreaswasenhancedunderthetreatmentbyCe3+oflowconcentration(0.5~10μmol*L-1),butwasinhibitedbyCe3+ofhighconcentration(>10μmol*L-1).Ce3+athighconcentrationdisplacedCa2+fromα-amylasecompetitively.Theequilibriumdialysisdemonstratesthatα-amylasehasfiveCa2+-bindingsiteswithdifferentaffinities.ThefluorescencetitrationshowsthatCe3+canbindtoCa2+-bindingsites.

  • 标签: Α-淀粉酶 酶活性 活化 叶绿体 稀土
  • 简介:Y-ModifiedUSYwaspreparedbyionexchangeofUSYslurrywith0.01mol·L-1Y(NO3)3.Phosphotungsticacid(HPW)catalystsupportedonUSYandY-USYwaspreparedbyanimpregnationmethod.ThematerialswerecharacterizedbyNH3-TPD,XRD,andN2adsorption.Theactivityfortheremovalofthiophenewasexaminedinathree-neckedflask.ThesulfurcontentofmodelcompoundwastestedonWK-2Dmicrocoulometricdetector.TheeffectofyttriumandHPWcontent,reactiontemperatureandcatalysts,activationtemperatureontheactivityofcatalystswereinvestigated.ItwasshownthattheoxidationactivityofthiophenedecreasedwiththeincreaseofYcontentexceptforthecatalystofY5%.HPWcontenthadlimitinfluenceonactivityofcatalysts.Theoptimalreactiontemperatureandactivationtemperaturewere40and320℃,respectively.

  • 标签: OXIDATION DESULFURIZATION YTTRIUM modification USY THIOPHENE
  • 简介:TheAu/CeO2catalystsweresynthesizedbyco-precipitation(CP),deposition-precipitation(DP)andmetalliccolloidsdeposition(MCD)method,andtestedforoxidationofvolatileorganiccompounds(VOCs).ItwasrevealedthattheAu/CeO2catalystpreparedbyDPmethodwasthemostefficientcatalysttowardsthetotaloxidationoftoluene.TheAu/CeO2catalystshadobviouslyhighcatalyticactivity,andthebestresultswasobtainedon3wt.%Au/CeO2catalystpreparedbyDPmethod.Thesecatalystswerechara...

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  • 简介:ThedopedZnOnanorodsasaphotocatalystwithdifferentEucontentswerepreparedbymicrowaveassistedmethodandtheywerecharacterizedbymeansofX-raydiffraction(XRD),energy-dispersiveX-rayspectroscopy(EDS),UV-Visspectroscopy,surfaceareaBrunauer-Emmett-Teller(BET),X-rayphotoelectronspectroscopy(XPS),scanningelectronmicroscopy(SEM)andtransmissionelectronmicroscopy(TEM).TheaveragecrystallitesizeandbandgapenergyofEu-dopedZnOwerevariedwiththeEucontent.TheXRDpatternofEu-dopedZnOindicatedhexagonalcrystalstructurewithanaveragecrystallitesizeof25nm.ThepresenceofeuropiumwithtrivalentstateanditsdopingsuccessfullyintothecrystallatticeofZnOmatrixwereconfirmedbyXPStechnique.ThephotocatalyticactivityofEu-dopedZnOnanorodswasevaluatedformethylorangedegradation.Thephotocatalyticexperimentsshowed~91%degradationofmethylorangeover0.2mol.%EudopedZnOsamplewithin3hunderUVlight(365nm).

  • 标签: 光催化活性 微波辅助 ZnO 纳米棒 铕掺杂 合成技术
  • 简介:AninorganicnanomaterialscombinationofSm,Ag,andTiO2wassynthesizedusingsupercriticalfluiddrying(SCFD)combinedwithsol-geltechniques.Thestructure,photocatalysisandbacteriostaticactivityofthematerialswerecharacterizedbyX-raydiffraction(XRD),transmissionelectronmicroscopy(TEM),X-rayphotoelectronspectroscopy(XRPS),photocatalyticperformance,andantibacterialactivityexperiments.TheXRDresultsshowedthattheaverageparticlediameterofSm/Ag/TiO2was14.62nmandAgandSmionsweredispersedonthesurfaceofTiO2inahighlydispersed,amorphousform.TheTEMimageshowedthatthesizeoftheparticlewas12nmusingtheschererformula.TheXPSresultshowedthattheelementSmwasdopedandAgwasloadedinorganicnanomaterialssuccessfully.Sm/Ag/TiO2exhibitedoptimalphotocatalyticpropertiesat600oC,thephotocatalyticoptimalproportionofSm/Ag/TiO2was2:2:100.Whenthemolarratiowas2:2:100,thebacteriostaticcirclediameterwas16mmforStaphylococcusaureus,theminimumbacteriostaticconcentrationwas200μg/mLforwhitebeadscoccus,andtheminimumbactericidalconcentrationwas2×104μg/mLforwhitebeadscoccus.TheSEMresultsshowedthattheantibacterialmaterialattachedtothecandidaalbicanscellsurface,cellsappearedfolddeformation.ThereforetheinorganicnanomaterialsSm/Ag/TiO2hadhightemperatureresistance,goodphotocatalyticandantibacterialcharacteristicsinvisiblelight.

  • 标签: 无机纳米材料 二氧化钛 抗菌活性 钐离子 合成 金黄色葡萄球菌
  • 简介:ThephotocatalystsK4Nb6017andK4Nb6017dopedwithFe^3+andCr^3+werepreparedbysolidstatereactionandwerecharacterizedbypowderx-raydiffraction,UV-visdiffusivereflectanceandscanningelectronmicroscopy.ThephotocatalyticactivityofK4Nb6O17andK4Nb6O17dopedwithFe^3+,Cr^3+wereinvestigatedwithmethanolaselectrondonorandPtaspromotercatalystunder+400nmUVirradiation.Thedifferenceofphotocatalyticactivitybetweenthemwasalsodiscussed.TheindividualrateofhydrogenevolutionfortheK4Nb6O17,Fe-K4Nb6O17andCr-K4Nb6O17asphotocatalystsare5.35,5.00,6.25mmol·L^-1.h^-1respectively.

  • 标签: 光接触反应活性 K4Nb6O17 铁离子 CR^3+ 冶炼方法 稀土元素
  • 简介:二高度光的铕(III)和铽(III)的准备有succinimide(SI)和N-hydroxysuccinimide(NHSI)的建筑群被报导,它进一步通过元素的化学分析,热分析,英尺红外,粉末X光检查衍射,SEM和荧光光谱学被调查。通过这些分析收集的数据揭示了Eu(III)的形成,有上面的Tb(III)建筑群对ligand在金属提及ligands(M:L)1:3的臼齿的比率。光中心从photoluminescent系列调查被保留的关于通过lanthanide的协作地点的有效促进感受性的有趣的结论。当时,强壮的光排放在Eu(III)-SI和Tb(III)-NHSI建筑群的情况下被观察-SI建筑群展出了的相应Eu(III)-NHSI和Tb(III)没有相片光性质。最新获得的光lanthanide建筑群可能具有为在光电子的各种各样的应用的特别兴趣。

  • 标签: 光致发光光谱 铕(Ⅲ) 铽配合物 羟基 稀土配合物 基础
  • 简介:Pd@Zr/CeO2core-shellcatalystpreparedbyhydrothermalmethodwasappliedinCOoxidationreaction,exhibitinghighCOoxidationactivityatlowtemperature.XRD(X-raydiffraction)analysisdemonstratedthattheremarkableenhancementofcatalyticperformancewasfoundtodependonthepresenceofmoreoxygenvacanciesinthecore-shellstructure,whichcontributedhighercontentofandreadyreleaseofactiveoxygenspeciesatlowtemperature,confirmedbyH2-TPR(temperatureprogramedreduction)results.Interestingly,introducingasmallamountofzirconium(0.5wt.%)exhibitedasignificantimprovementofcatalyticactivitybecausetheintroductionofZrfurtherimprovedtheamountofcrystaldefectsandpromotedthemigrationofoxygenspecies.

  • 标签: 一氧化碳氧化 催化剂 钯核 封装 X射线衍射 低温度
  • 简介:有不同元素dopings的极其细小的基于Ce的氧化物nanoparticles(Zr,Y)被传播micropores的一起沉淀(MDC)的方法作为降水代理人用氨答案综合。为煤烟氧化的催化剂的活动被规划温度的氧化(TPO)评估反应。基于Ce的氧化物在这准备了学习为在在煤烟粒子和催化剂之间的松开的接触的条件下面的煤烟氧化的展出高催化的活动,和为煤烟燃烧的极其细小的Ce0.9Zr0.1O2nanoparticle的催化活动最高,364是其T10,T50和SCO2m,442???‰眠?ㄥ‵瑷吗?

  • 标签: 纳米颗粒 催化性能 碳烟氧化 氧化物 超细 制备
  • 简介:AseriesofMn-basedcatalysts,MnOx,MnOx-CeO2,Pd-Mn-Ce,MnOx/ACwereprepared.AndtheirperformancesforNOlow-temperatureSCRwereinvestigatedinthisstudy.TheNOconversionisabout90%at100℃onMnOx-CeO2andalmostallNOcanbeconvertedat120℃.SimilarresultsarealsoobservedinthetestsonMnOx-CeO2/AC.Theexcellentlow-temperaturecatalyticactivityofmodifiedMn-basedcatalysts,whichmaybemainlyduetotheoxygenstoragefunctionofCeO2,canimprovetheoxygenflowonthecatalystssurface.ThentheoxidationofNOtoNO2isaccelerated,whichisthekeystepofNOSCR.

  • 标签: LOW-TEMPERATURE SELECTIVE CATALYTIC reduction (SCR) NO
  • 简介:Fe/Cu/Cemodifiedcoal-basedactivatedcarbon(AC)waspreparedbythesol-gelmethod,andtheeffectofFe/Cu/CeoncatalyticpropertiesofFe/AC,Fe-Cu/ACandFe-Cu-Ce/ACwasinvestigatedinthehydrolysisofcarbonylsulfide(COS)at50°C.Theirsurfacepropertieswereevaluatedbymeansofnitrogenadsorptionandwerecharacterizedbyusingscanningelectronmicroscopy(SEM),X-raydiffracto-metry(XRD)andX-rayphotoelectronspectroscopy(XPS).ThecatalyticactivitiesresultsshowedthatadditionofCuandCe...

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  • 简介:我们在甲烷(POM)的部分氧化上调查了填满的格子氧的锻烧温度,反应温度,和不同数量的效果到把perovskite类型LaFeO3氧化物用作氧施主而不是气体的氧的合成气体,它被大音阶的第五音胶化方法准备,并且氧化物被XRD,TG/DTA,和赌注描绘。结果显示粒子尺寸增加了,锻烧温度增加,当赌注和CH4变换衰退了,锻烧温度当气体的氧不在时作为氧施主用LaFeO3氧化物增加时。在象上面那样的高水平仍然是的公司选择92%,并且当锻烧温度增加了,稍微增加了。到甲烷空气的LaFeO3氧化物的暴露提高了氧迁居在有由于格子氧和氧化说的Fe离子的减小的损失联机的时间的体积同时。高反应温度对从向为有高公司选择的合成气体生产的表面的体积的氧种类的迁居有利。为由顺序的氧化还原作用反应的POM的产品分发和进化被填满的格子氧的数量与气体的氧决定。最佳的过程应该衰退甲烷的全部的氧化,和增加甲烷的部分氧化的选择。

  • 标签: 钙钛矿 LAFEO3 合成气体 氧化还原 稀土
  • 简介:AnovelTb(III)ternarycomplexTb(p-BBA)_3MAAwassynthesizedwith4-benzoylbenzoicacid(p-BBA)andmethacrylicacid(MAA)asligands.ThecomplexwascharacterizedbyIR,UV-visible,thermogravimetricanalysisandfluorescencespectroscopy.Monitoredat544nm,thecomplexdisplayedwideandstrongexcitationbandat300–400nm,whichmatchedwellwiththe365nm-emittingUVchip.Thecomplexexhibitedexcellentgreenemissionat544nm(~5D_4→~7F_5transitionofTb~(3+))underanexcitationat365nm.Besides,thecomplexshowedhighthermalstability.Itsintramolecularenergytransferprocesswasfurtherdiscussed.Furthermore,thecomplexalsohadhigherfluorescencelifetime(1.38ms)andhigherquantumyield(0.372).Finally,electroluminescentpropertiesindicatedthatwhenusedtofabricateLEDwith365nmUVchip(powerefficiencyis18.6lm/W),thecomplexremaineditsfavorableopticalperformance.TheseresultsimpliedthatTb(p-BBA)_3MAAcouldbeusedasagreenphosphorforNUV-basedwhiteLED.

  • 标签: LUMINESCENT excitation FABRICATE visible LIFETIME phosphor
  • 简介:四lanthanide协作建筑群,也就是[行(2,3-DClBA)3(5,5-dmebipy)(H2O)]2(Ln=Sm(1),Eu(2),Dy(3),惊讶(4));2,3-DClBA=2,3-dichlorobenzoate;5,5-dmebipy=5,5-dmethylbipyridine)被元素的分析,红外线的光谱学和单个水晶X光检查衍射综合并且描绘。调查结果显示建筑群3是一个dinuclear分子,并且中心Dy3+是八坐标的。每个dinuclear单位能被H债券和卤素卤素相互作用连接。建筑群2的光性质建议了Eu3+离子的典型强烈排出物。热分析证明建筑群在三分解了步:协作水然后第一被失去中立ligand5,5dmebipy被失去,最后,2,3-DClBAligand被失去。

  • 标签: lanthanide 建筑群 水晶结构 超分子 H 债券 卤素卤素相互作用 光性质
  • 简介:RE-dopedNi-basedcatalystswerepreparedbysol-gelmethod.ThesecatalystswereappliedtothereactionofCO2reformingCH4tosyngas.ThestudiesrevealthatRE-doped(RE=La,Ce,Sm,Yb)Ni-basedcatalystsshowhighercatalyticactivitythanundopedNi-basedcatalyst,andwiththeincreasingofRE-dopedquantity,thecatalyticactivityofcatalystsexhibitsregularchanges.WhenRE-dopedquantityis0.2%(molarratio),thecatalystsshowthebestcatalyticactivity.

  • 标签: DOPE BATIO3 CATALYST RARE earths