简介：DistributionofmetalsonPd-SnO2/D3520catalystsandstateofthecatalystswrerstudiedwithSEM,XRD.TheinteractionbetweenmetalsandsupportorbetweenPdandSnorPbwerestudiedbyIR,XPS.Inaddition,therelationshipoftheactivityforcatalytichydrogenationoftheolefinsandouterlayervalenceelectrondensityofPdwasdiscussed.Theresultsshowedthatthesecatalystshadsuitablesurfacestate,themetalswereuniformlydispersedonthesurfacelayerofthesupport.Therewerenotobviousinteractionbetweenthemetalsandthesupport.TherewasstronginteractionbetweenPdandSn(orPb)inthecatalysts.ThecatalyticactivityforhydrogenationwasrelatedtoouterlayervalenceelectrondensityofPd.
简介：DistributionofmetalsonPd-SnO2/D3520catalystsandstateofthecatalystswerestudiedwithSEM,XRD.TheinteractionbetweenmetalsandsupportorbetweenPdandSnorPbwerestudiedbyIR,XPS.Inaddition,therelationshipoftheactivityforcatalytichydrogenationoftheolefinsandouterlayervalenceelectrondensityofPdwasdiscussed.Theresultsshowedthatthesecatalystshadsuitablesurfacestate,themetalswereuniformlydispersedonthesurfacelayerofthesupport.Therewerenotobviousinteractionbetweenthemetalsandthesupport.TherewasstronginteractionbetweenPdandSn(orPb)inthecatalysts.ThecatalyticactivityforhydrogenationwasrelatedtoouterlayervalenceelectrondensityofPd.
简介：NanocrystallineSnO2wassynthesizedbydirectmixingandgrindingofSnCI4-5H2OandNaOHatroomtemperature,followedbycalcinationatdifferenttemperaturesfordifferenttimesinair.ProductsampleswerecharacterizedbyX-raydiffractionandtransmissionelectronmicroscope,revealingthattheamorphousprecursorSnO2wastransformedtocrystalsat200℃for3h,andthattheaverageparticlesizeincreaseduponraisingthecalciningtemperatureorprolongingthecalciningtime.Themechanismofthephasetransformationoftheproductsisdiscussed.
简介：TheepoxidationofallylchloridewithH2O2onTi-ZSM-5preparedbyisomorphoussubstitutionofHZSM-5withTiCl4gaswasstudied.TheresultsshowthatTi-ZSM-5hasahighcatalyticefficiencyfortheepoxidationofallylchloride.TheH2O2utilizationreaches99.50%whentheallylchloride/H2O2molarratiois>1.Theeffectofsolventspecies,catalystconcentration,H2O2andallylchlorideconcentrationandreactiontemperatureontheepoxidationwasinvestigatedsimultaneously.Itisfoundthatmethanolisthebestsolventforthereaction.Thereactionrateequationwithv=k[Cat.][H2O2]1/2-[C3H5Cl]andtheapparentactivationenergywithEa=63.462kJ/molareobtainedaccordingtothekineticsstudy.
简介：AnewSnO_2-Fe_2O_3/SWCNTs(single-walledcarbonnanotubes)ternarynanocompositewasfirstsynthesizedbyafacilehydrothermalapproach.SnO_2andFe_2O_3nanoparticles(NPs)werehomogeneouslylocatedonthesurfaceofSWCNTs,asconfirmedbyX-raydiffraction(XRD),transmissionelectronmicroscope(TEM)andenergydispersiveX-rayspectroscopy(EDX).Duetothesynergisticeffectofdifferentcomponents,theassynthesizedSnO_2-Fe_2O_3/SWCNTscompositeasananodematerialforlithium-ionbatteriesexhibitedexcellentelectrochemicalperformancewithahighcapacityof692mAh·g~(-1)whichcouldbemaintainedafter50cyclesat200mA·g~(-1).Evenatahighrateof2000mA·g~(-1),thecapacitywasstillremainedat656mAh·g~(-1).
简介：Zn2SnO4(ZTO)nanowireswithauniquedendriticnanostructureweresynthesizedviaasimpleone-stepthermalevaporationandcondensationprocess.ThemorphologyandmicrostructureoftheZTOnanodendritehavebeeninvestigatedbymeansoffieldemissionscanningelectronmicroscopy(SEM),x-raydiffraction(XRD)andhigh-resolutiontransmissionelectronmicroscopy(HRTEM).SEMobservationrevealedtheformationofbranchednanostructuresandshowedthateachbranchexhibitedauniqueperiodicstructureformedbyarowofoverlaidrhombohedraofZTOnanocrystalsalongtheaxisofthenanobranch.HRTEMstudiesdisplayedthatthebranchesgrewhomoepitaxiallyassingle-crystallinenanowiresfromtheZTOnanowirebackbone.ApossiblegrowthmodelofthebranchedZTOnanowiresisdiscussed.Tosuccessfullypreparebranchedstructureswouldprovideanopportunityforbothfundamentalresearchandpracticalapplications,suchasthree-dimensionalnanoelectronics,andopto-electronicnanodevices.
简介：TiO2nanoparticlesweresynthesizedbyahomogeneouscontrolledprecipitationmethodusingindustrialtitaniumsulfate(Ti(SO4)2).TheobtainedpowderswerecharacterizedbyX-raydiffraction(XRD),transmissionelectronmicroscope(TEM),Fouriertransforminfraredspectroscopy(FTIR)andICPplasmaspectrometer.EDTAwasusedascomplexingagenttoimprovethepurityandtheformationofTiO2nanoparticles.Experimentalresultsindicatedthatthehigh-purityTiO2nanoparticleswere20nminmeansizeandnearlymonodispersed.
简介：PtRu/SnO2/Ccatalystwaspreparedinapolyolprocess,followedbyreductiontreatmentandalkalineetching.X-raydiffraction,transmissionelectronmicroscopewithenergydispersivespectrometerandXrayphotoelectronspectroscopywereusedtocharacterizethemorphology,structureandcompositionofthecatalysts.COandmethanolelectro-oxidationactivitiesofthecatalystswereevaluatedbyCOstrippingvoltammetry,cyclicvoltammetryandchronoamperometrymeasurements.ReductiontreatmentofthepreparedPtRuSnO2/CcatalystinapolyolprocessinducedtheenrichmentofSnonthesurface,inhibitingmethanoldissolutionandCOadsorptiononPt.AlkalineetchingremovedSnorSnOxandthusexposedPtRuonthesurface,resultinginenhancedactivitiesforCOandmethanolelectro-oxidationduetothesynergyeffectsofPtRuonthesurfaceandSnspeciesbeneath.
简介：RuO_2nanoparticlessupportedonmulti-walledcarbonnanotubes(CNTs)functionalizedwithoxygen(OCNTs)andnitrogen(NCNTs)wereemployedfortheoxygenevolutionreaction(OER)in0.1MKOH.Thecatalystsweresynthesizedbymetal-organicchemicalvapordepositionusingrutheniumcarbonyl(Ru_3(CO)_(12))asRuprecursor.TheobtainedRuO_2/OCNTandRuO_2/NCNTcompositeswerecharacterizedusingTEM,H_2-TPR,XRDandXPSinorderprobestructure–activitycorrelations,particularly,theeffectofthedifferentsurfacefunctionalgroupsontheelectrochemicalOERperformance.TheelectrocatalyticactivityandstabilityofthecatalystswithmeanRuO_2particlesizesof13–14nmwasevaluatedbylinearsweepvoltammetry,cyclicvoltammetry,andchronopotentiometry,showingthatthegenerationofnitrogen-containingfunctionalgroupsonCNTswasbeneficialforbothOERactivityandstability.InthepresenceofRuO_2,carboncorrosionwasfoundtobesignificantlylesssevere.
简介：Twonewdicyanamidecoordinationpolymers,{Mn(dmpz)[N(CN)2]2}2(1)and{Cu(dmpz)[N(CN)2]2}2(2)(dmpz=3,5-dimethylpyrazole),weresynthesizedandcharacterizedbysinglecrystalX-raydiffractionanalysisandIRspectroscopy.In1and2themetalionshavetwodifferentcoordinationmodes,whereoneiscoordinatedtofourdicyanamideanionsandtwomonodentatedmpzmoleculestoformaslightlydistortedoctahedralgeometry,whiletheotheradoptsoctahedralgeometry,surroundedbyfournitrileNatomsandtwoamideNatomsofthedicyanamideanions.Bothcomplexescontaintwoalternatingchainsthatareparalleltoeachother.
简介：Hypersubstitutions是印射操作符号到相应arities的术语的地图砰。他们作为使ahyperidentity和归纳的概念精确到M-hyperidentities的一个方法被介绍。每身份作为亢奋的身份在满足的一个变化被称为固体。如果每身份是为子集Mof的M-hyperidentity所有亢奋的替换的集合，变化被称为M固体。在亢奋的替换的单音的标志和一种给定的类型的代数学的所有变化的格子的潜水艇格子之间有一个Galois连接。因此，知道怎么有趣、有用半组或在到M固体变化的相应格子的性质的这个Galois连接下面的亢奋的替换转移的单音的标志性质ofmonoids。在这篇论文，我们学习类型(2,2)的eachhypersubsfitution的顺序，即，周期的subsemigroup的顺序由类型的所有亢奋的替换的单音的标志的thathypersubstitution产生了(2，2)。主要结果是顺序是1，2，3，4或无限。
简介：ThesplittingofpotentialenergylevelsforgroundstateX2ΠgofOx2(x=+1,1)underspin–orbitcoupling(SOC)hasbeencalculatedbyusingthespin–orbit(SO)multi-configurationquasi-degenerateperturbationtheory(SO-MCQDPT).TheirMurrell–Sorbie(M–S)potentialfunctionsaregained,andthenthespectroscopicconstantsforelectronicstates2Π1/2and2Π3/2arederivedfromtheM–Sfunction.TheverticalexcitationenergiesforOx2(x=+1,1)areν[O+12(2Π3/2→X2Π1/2)]=195.652cm1,andν[O12(2Π1/2→X2Π3/2)]=182.568cm1,respectively.Allthespectroscopicdataforelectronicstates2Π1/2and2Π3/2aregivenforthefirsttime.
简介：WedemonstrateafacilerouteforthemassiveproductionofSnCb/carbonnanocompositeusedashigh-capacityanodematerialsofnextgenerationlithium-ionbatteries.ThenanocompositehadauniquestructureofultrafineSnO2nanocrystals（5nm,80wt%）homogeneouslydispersedinamorphouscarbonmatrix.ThisstructuredesigncanwellaccommodatethevolumechangeofLi+insertion/desertioninSnO2,andpreventtheaggregationofthenanosizedactivematerialsduringcycling,leadingtosuperiorcycleperformancewithstablereversiblecapacityof400mAh/gatahighcurrentrateof3.3A/g.
简介：ThecrystalstructureofDi-nitratobis（ethylcaprolactam）uranyl（Ⅱ）UO2[CH2（CH2）4CONC2H5]2（NO3）2wasestablishedbyasingle-crystalX-raydiffractionstudy.Itistriclinie,spacegroupP1,witha=7.171（2）,b=8.655（3）,c=10.182（5）A,α=78.27（3）,β=70.63（3）,γ=81.76（3）°,V=581.7（4）A3,Z=l,Dc=1.94g.cm-3.FinalRvalueis0.0218.Theresultrevealsthaturanylioniscoordinatedtosixoxygenatoms,twoofthemarefromtwocarbonylgroupsofethylcaprolactamandtheotherfourarefromtwonitrategroups.
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![Two New Dicyanamide Coordination Polymers with Alternating Parallel Chains： {Mn（dmpz）[N（CN）<b style='color:red'>2</b>]<b style='color:red'>2</b>}<b style='color:red'>2</b> and {Cu（dmpz）[N（CN）<b style='color:red'>2</b>]<b style='color:red'>2</b>}<b style='color:red'>2</b>](/image/thesis13 "Two New Dicyanamide Coordination Polymers with Alternating Parallel Chains： {Mn（dmpz）[N（CN）<b style='color:red'>2</b>]<b style='color:red'>2</b>}<b style='color:red'>2</b> and {Cu（dmpz）[N（CN）<b style='color:red'>2</b>]<b style='color:red'>2</b>}<b style='color:red'>2</b>")
![CRYSTAL STRUCTURE OF DI - NITRATOBIS（ETHYLCAPROLACTAM）URANYL（Ⅱ） UO<b style='color:red'>2</b>[CH<b style='color:red'>2</b>（CH<b style='color:red'>2</b>）4CONC<b style='color:red'>2</b>H5]<b style='color:red'>2</b>（NO3）<b style='color:red'>2</b>](/image/thesis18 "CRYSTAL STRUCTURE OF DI - NITRATOBIS（ETHYLCAPROLACTAM）URANYL（Ⅱ） UO<b style='color:red'>2</b>[CH<b style='color:red'>2</b>（CH<b style='color:red'>2</b>）4CONC<b style='color:red'>2</b>H5]<b style='color:red'>2</b>（NO3）<b style='color:red'>2</b>")
