简介：Graphiteintercalationcompounds(GIC)weretestedasanexperimentalmodelforstudyingtheelectroniceffectofcarbonsupportonthecatalyticactivityandpoisoningtoleranceofPtcatalystfordirectmethanolfuelcells.TheGICsampleswithdifferentintercalationdegreeswerepreparedbyelectrolyzinggraphiteflakeinH2SO4forvaryingtheperiodsoftime.TheGIC-supportedPtcatalystwasdepositedelectrochemically.ThecatalyticactivityandpoisoningtoleranceoftheGIC-supportedPtcatalystswereevaluated.ItwasfoundthatGICwithsulfateanionasintercalatewasabletocatalyzemethanolelectrooxidation,whichcouldberelatedtothepositivechargesgeneratedonthegraphitelayeruponintercalation.Asintercalationdegreeincreased,thecatalyticactivityoftheGIC-supportedPtcatalystdecreasedwhilethepoisoningtoleranceimproved.ThissuggeststhatelectrondonationfromsupporttocatalysthadgreateffectonbothcatalyticactivityandpoisoningtoleranceofPtcatalyst.Andintercalationcanbeadoptedasanotherimportantwaytomakemodificationoncarboneouscatalystsupport.

简介：CarbonsupportedPt(Pt/C)electrocatalystswerepreparedwithglucoseasprotectionagentandNaBH4asreductant.ThePtnanoparticlesdepositedoncarbonsupportpresentedreducedsizeandwelldispersityattributedtotheprotectioneffectofglucose.GlucoseabsorbedontheparticlesurfacewasreadilyremovedbywaterwashingwithoutleadingtoagglomerationofthePtnanoparticles.Theas-preparedPt/Celectrocatalystsshowedimprovedmassactivityformethanolelectrooxidationcomparedtothecatalystpreparedwithoutglucoseprotection.TheimprovedperformanceisattributedtothelargerelectrochemicalactivesurfaceareathusincreasedactivesitesonthePt/Celctrocatalystspreparedundertheprotectionofglucose.

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简介：ElectrolyticfixationofCO2wasinvestigatedbyelectrocarboxylationoforganichalides(RX),andfourestersⅠ,ⅡⅢ,Ⅳ)wereobtainedinmoderateyields.ElectrochemicalreductionesterificationsofRXinthepresenceofCO2werecarriedoutonnanocry'stallineTiO2-Ptelectrode.TheelectrochemicalbehaviorofRXinthepresenceofCO2wasinvestigatedbythetechniqueofcyclicvoltammetry,andtheprobablereactionmechanismw,asproposed.

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简介：运用电化学循环伏安和石英晶体微天平研究了1,4-丁二醇(1,4-BDL)在Pt电极及以Sb和S吸附原子修饰的Pt(Pt/Sbad和Pt/Sad)电极上的吸附和氧化过程.结果表明,1,4-丁二醇的氧化与电极表面氧物种有着极其密切的关系,表面质量变化提供了吸附原子电催化作用的新数据.Pt电极表面Sb吸附原子能在较低的电位下吸附氧,可显著提高1,4-丁二醇电催化氧化活性.与Pt电极相比,1,4-丁二醇在饱和吸附Sb原子的Pt电极上氧化的峰电位负移了0.20V,峰电流增加了1.5倍.相反,Pt电极表面S吸附原子的氧化会消耗表面氧物种,饱和吸附的S原子抑制了1,4-丁二醇的氧化.

简介：采用密度泛函理论(DFT)CAM-B3LYP方法,计算研究了10个设计的Ni(salen)与Pt(salen)配合物的几何结构、电子光谱和二阶非线性光学性质.结果表明,此类配合物有较大的第一超极化率βtot,且βtot值随配体苯环对位推拉电子基团的给体-π-受体(D-π-A)作用增强而显著提高,在配体结构中存在显著D/A作用基团时,Pt(salen)系列配合物的βtot值大于Ni(salen)系列.D/A给受电子引起的电荷转移对此系列配合物βtot值的影响大于不同金属对其影响.

简介：ThispaperreportsasimpleandhighlyselectivemethodforpreconcentratingandseparatingoftracePd(II)andPt(IV)withsilicagelbondedbyaminopropyl-benzoylazo-4-(2-pyridy-lazo)-resorcinol(ABPR-SG).ABPR-SGisstableinsolutionfrom6mol/LHCltopH7.0andincommonorganicsolvents.ThemaximumadsorptivecapacityofPd(n)onABPR-SGis362μmol/g.AfterpreconcentrationandseparationbyusingABPR-SGcolumn,Pd(II)andPt(IV)ofμg/Llevelinartificialwatersamplescanbemeasuredreliablybycommonspedrophotometry.ThemaximumconcentrationfactorsofPd(II)andPt(IV)onABPR-SGcolumnare143and125respectively.ThechromatographiccolumnpackedwithABPR-SGcanbereused.Themethodissimpleandefficient.

简介：采用微波加热法制备了炭黑XC-72负载的系列AuPt/C催化剂和Pt/C催化剂,利用XRD和TEM技术对催化剂的组成、结构和形貌进行了表征,通过循环伏安法和CO溶出循环伏安法考察了在含有Keggin型H3PMo12O40支持电解质中催化剂的抗CO中毒能力.结果发现,AuPt/C催化剂为非合金双金属体系,粒径范围4～10nm;AuPt/C催化剂在含有Keggin型H3PMo12O40的电解质溶液中表现出良好的抗中毒能力,这被认为是Au和H3PMo12O40协同作用.

简介：0.5%Pt-K/γ-Al2O3catalystsforthesynthesisofo-phenylphenol(OPP)fromo-cyclohexenyl-cyclohexanone(dimer)dehydrogenationwerepreparedbymeansofatwosubsequentimpregnationmethod.Theeffectsofcatalystpreparationparameters,suchasKpromoters,calcination,andreductionconditions,wereinvestigated.TheresultsshowedthattheadditionofK2SO4toPt/γ-Al2O3catalystnotablypromotedtheselectivityofOPP,anditsoptimumcontentwasfoundtobe6%inmassfraction.ThehigheractivitywasobtainedwhenPt/γ-Al2O3catalystwascalcinedinnitrogenatmosphereat400―500°Candthenreducedatthesametemperaturefor3hinhydrogenatmosphere.TheconversionofthedimerandtheselectivityofOPPwerealwaysabove99%and90%,respectively,over0.5%Pt-6%K2SO4/γ-Al2O3catalystduringthepilotscaletestof8000h.

简介：采用密度泛函方法(B3LYP)优化了MX2(AsH3)2[M=Pd;X=Cl(1),Br(2),I(3)和M=Pt;X=Cl(4),Br(5),I(6)]的基态结构,得到的几何参数与实验结果符合.以基态几何为基础,将TD-DFT方法用于计算标题配合物的电子吸收光谱.研究结果表明,金属的dx2-y2与配体所组成的反键轨道为LUMO轨道,从而该类配合物具有d-d跃迁属性的吸收带;在多数跃迁过程中,配体也有较大的贡献.

简介：主要介绍了理学ZSXPrimusⅡX射线荧光光谱仪的一些日常保养和出现故障的现象及处理方法。