简介:缩放Nano的氧化钇粒子基于含水的钇硝酸盐和乙二醇经由非水的sol-gelprocess被综合。到雏晶上的钇离子和锻烧温度的乙二醇的臼齿的比率的效果产品缩放我们再学习。为铵perehlorate(AP)的同样准备的氧化钇的催化表演分解被微分扫描调查热量测定(DSC)。结果显示有在平均雏晶尺寸的不到20nm的缩放nano的立方的氧化钇粒子能在70degC在2h倒流以后被获得,在90degC弄干,形成xerogel,并且由为2hxerogel退火列在后面,并且到AP的缩放nano的氧化钇的增加在温度合并AP的二座小发热的山峰,这310~变化350degC并且400-470degC进AP和增加的一座强壮的发热的山峰从515的明显的分解热到超过1110Jcentre点g~(-1)。发热的山峰减少和明显的分解AP加热的AP分解的温度随数量的增加增加缩放ofnano的氧化钇,也是清楚的。到AP的5%缩放nano的氧化钇的增加减少的事实到由114.6degC的减小的337.7degC的AP发热的山峰的温度,并且从515~1240J中心点g~增加明显的分解热(-1),揭示那缩放nano的氧化钇hows为AP的强壮的催化性质热分解。
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简介:以六水合氯化钴(CoCl2·6H2O)和水合三氯化钌(RuCl3·3H2O)为前驱体,采用胶体法制备超级电容器用(RuO2/Co3O4)·nH2O复合薄膜电极材料。用X射线衍射仪以及CHl660C电化学工作站对该复合薄膜的物相结构及电化学性能进行表征。结果表明:当COCl2'6H20和RuCl3·3H2O的物质的量比n(Co):n(Ru)为2:1时,于350℃下热处理2.5h制备的复合薄膜电极具有优良的性能,在浓度为0.5mol/L的H2S04电解液中其比电容达到512F/g,500次充放电循环后比电容量保持在充放电循环前的96.1%;充放电电流为0.01A时,内阻为1.2Ω。
简介:用滚镀的方法在金刚石表面镀Ni层和纳米Si3N4/Ni复合镀层,用扫描电子显微镜观察金刚石镀前和镀后的表面形貌,用DKY-1型单颗粒抗压强度测定仪测量金刚石单颗粒的抗压强度。用热压烧结的方法得到铁基结合剂金刚石节块,在INSTRON-5569型万能材料试验机上测量节块的抗弯强度,在NMW-1立式万能摩擦磨损试验机上测试节块的耐磨性。结果表明:在金刚石表面镀Ni层和纳米Si3N4/Ni复合镀层后,表面镀层均匀,纳米Si3N4/Ni复合镀层比纯Ni层更致密,更平滑,晶粒更细小;纳米Si3N4/Ni复合镀层金刚石单颗粒有更高的抗压强度;纳米Si3N4/Ni复合镀层金刚石铁基结合剂节块有更高的抗弯强度和更优良的耐磨性。
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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.
简介:增加的CeO2(ZrO2)/TiO2催化剂独立由大音阶的第五音胶化和受精的方法准备了的一系列镨为选择催化减小被测试没有,并且由X光检查衍射(XRD)描绘了,N2-brumauer-emmett-teller(N2-BET),NH3-temperature规划了解吸附作用(NH3-TPD),H2-temperature规划了减小(H2-TPR),PL系列,拉曼系列,电子顺磁的回声(EPR)一催化性能上的准备方法的影响被学习。结果证明CeO2(ZrO2)/TiO2催化剂的催化性能上的Pr增加的影响在大音阶的第五音胶化方法和受精方法之间是不同的。Pr增加趋于与TiO2交往并且当它是更可能的与在受精方法形成Ce-O-Pr的结构的CeO2交往时,在大音阶的第五音胶化方法形成了Ti-O-Pr的结构。大音阶的第五音胶化方法准备的催化剂的全部的酸数量和氧化还原作用性质与Pr元素的增加减少了,它导致了催化活动的减少。相反,受精方法准备的增加Pr的催化剂被发现拥有更容易的reducibility,更多的全部的酸数量和Ce3+种类的更高的比例,它为更高催化的活动是赞成的。
简介:ThesinglecrystalgrowthofstoichiometrichostluminescentcrystalNa5Eu(WO4)4hasbeeninvestigated.UsingNa2WO4asaflux,theoptimumconditionstogrowapuresinglecrystalbyflux-slow-coolingmethodhavebeendetermined.Ahighopticalqualitysinglecrystalofdimention4.5mmhasbeengrown,whichisthelargestoneasweknowsofar.Themicro-hardnessofNa5Eu(WO4)4singlecrystalis3.46×103MPa.Itsrefractiveindexis1.81inwhitelightwavelengthregionandthespecificgravityis5.65g/cm3.Thefluorescentandexcitationspectrahavebeendeterminedandthereasonofthefluorescentquenchof5D2and5D1to7FjofEu3+canbeexplainedasmulti-phononnon-radiationtransition.
简介:Thecrackingandaromatizationofn-hexaneoverH-ZSM-5modifiedbyvariousrareearthswereinvestigatedbymeansofcontinuousflowmicro-reactor.ThesurfacepropertiesofmodifiedH-ZSM-5catalystswereobtainedfromIR,XRDandXPS.Theresultsshowthattherareearthsenhancethearomatizingpropertiesofthecatalystswhicharepreparedbymechanicalmixturemethod.Theresultsofn-hexanecrackingandaromatizationarecorrelatedwiththeacidity.TheBrnstedacidicsitesaretheactivesitesofn-hexanearomatization,whileLewisacidsiteplaysanimportantroleinn-hexanecracking.
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:SeveralREEdatasetswerecollectedinCoreDD2andEC2005intheinnershelfofEastChinaSea,CoreY127inthenorthernOkinawaTrough,CoreNT1,C9247andC92169inthesouthYellowSeatochecktheapplicabilityoftheδEuN-ΣREEsmodelforquantita-tivelydistinguishingsedimentsfromtheYangtzeRiverandtheYellowRiver.Bycomparison,severalsedimentsincoresDD2,EC2005,Y127aregenerallyinaccordancewiththismodel.ThecoresNT1,C9247andC92169,whichhavebeeninfluencedbytheYangtzeRiverandtheYellowRivertogether,however,wereinconsistentwiththeδEuN-ΣREEsmodel.TheδEuN-ΣREEsplotanditscorrespondingregressionequation,whichcouldbeusedtodistinguishsediments"intuitivelyandquantitatively"fromtheYangtzeRiver,andtheYellowRivershouldbereconsideredorreassessed.
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。
简介:ThephotoluminescencepropertiesofBiTaO4∶Pr3+andBiTaO4atroomtemperaturewerestudied,andtheinfraredtransmissionanddiffusionreflectionspectraofBiTaO4weremeasured.ThephotoluminescencespectrumofBiTaO4peaksatabout420,440and465nm.Therehasanobviousexcitationbandfrom330to370nm.ThephotoluminescencespectrumofBiTaO4∶Pr3+consistsofthecharacteristicemissionofPr3+,anditsmainpeakisat606nmfrom3P0→3H6transitionofPr3+.Itsexcitationspectrumconsistsofthewidebandwithmaximumat325nm,thewidebandintherangeof375~430nm,andthecharacteristicexcitationofPr3+.Thebandsat325nmand375~430nmmaybefromtheabsorptionofthechargetransfertransitionofthetantalategroupanddefectenergylevelsinitsforbiddenband,respectively.ThereisenergytransferfromhosttoPr3+.BecauseboththehostdensityandphotoluminescencepeakintensityofBiTaO4∶Pr3+aresuperiortoPbWO4,BiTaO4∶Pr3+maybeapotentialheavyscintillator.