简介：Inthisletter,Fe2O3UFP（UltrafineParticles）hydrosolandorganosolwithhighthirdorderopticalnonlinearsusceptibility（3）havebeenreportedforthefirsttime.ThesurfacialmodificationofFe2O3UFPwithdodecylbenzenesulfonateions（DBS）canenhancethenonlinearopticalresponsethroughinterfacialconfinementofelectronmotion.Theinvolvedmechanismisdiscussed.
简介：Nanostructuredγ-Al2O3withhighsurfaceareaandmesoporousstructurewassynthesizedbysol-gelmethodandemployedascatalystsupportfornickelcatalystsinmethanereformingwithcarbondioxide.ThepreparedsampleswerecharacterizedbyXRD,N2adsorption-desorption,TPR,TPO,TPH,NH3-TPDandSEMtechniques.TheBETanalysisshowedahighsurfaceareaof204m2g-1andanarrowpore-sizedistributioncenteredatadiameterof5.5nmforcatalystsupport.TheBETresultsrevealedthatadditionoflanthanumoxidetoaluminumoxidedecreasedthespecificsurfacearea.Inaddition,TPRresultsshowedthatadditionoflanthanumoxideincreasedthereducibilityofnickelcatalyst.Thecatalyticevaluationresultsshowedanincreaseinmethaneconversionwithincreasinglanthanumoxideto3mol%andfurtherincreaseinlanthanumcontentdecreasedthecatalyticactivity.TPOanalysisrevealedthatthecokedepositiondecreasedwithincreasinglanthanumoxideto3mol%.SEMandTPHanalysesconfirmedtheformationofwhiskertypecarbonoverthespentcatalysts.AdditionofsteamandO2todryreformingfeedincreasedthemethaneconversionandledtocarbonfreeoperationincombinedprocesses.
简介：Multilayerblackphosphorus（BP）nanoplateletsofdifferentthicknesseswerepreparedbytheliquidphaseexfoliationmethodanddepositedontoyttriumaluminumgarnetsubstratestoformsaturableabsorbers（SAs）.Thesewerecharacterizedwithrespecttotheirthickness-dependentsaturableabsorptionpropertiesat3μm.TheBP-SAswereemployedinapassivelyQ-switchedEr:Lu2O3laserat2.84μm.ByusingBPexfoliatedindifferentsolvents,stablepulsesasshortas359nsweregeneratedatanaverageoutputpowerofupto755mW.Therepetitionrateintheexperimentwas107kHz,correspondingtoapulseenergyof7.1μJ.TheseresultsprovethatBP-SAshaveagreatpotentialforopticalmodulationinthemid-infraredrange.
简介：Erbium,Ytterbium-codopedZrO2nanoparticles(ZrO2∶Er3+,Yb3+)werepreparedbythesol-emulsion-geltechnique.Thepurposeofthepresentstudyistheapplicationofupconversionphosphorinthebiologicallabel.Inordertomakeoutthemechanismofupconversionunder980nmexcitationthe488nmpumpwasused.Theinfluenceoftemperatureonthecrystallitephasewasstudied.TheresultsconfirmtheupconvertedmechanisminZrO2∶Er3+,Yb3+nanocrystalsisduetoanenergytransferupconversion(ETU).
简介：CaF2:Ho3+/Yb3+nano-particleswithintensegreenup-conversion(UC)luminescencearesuccessfullysynthesizedviaafacilehydrothermalapproachbyusingNH4FasthefluoridesourceandNa2EDTAasachelatingreagent.PowderXraydiffraction(XRD),transmissionelectronmicroscopy(TEM),fieldemissionscanningelectronmicroscopy(FE-SEM),andUCemissionspectraareusedtocharacterizethestructures,shapes,andluminescentpropertiesofthesamples.TheeffectsfromfluoridesourcesandchelatingreagentsontheformationsofCaF2nano-particlesareinvestigated,andtheformationprocessisalsodeduced.Undertheexcitationofa980-nmlaserdiode,thesampleseachshowagreenup-conversionemissioncenteredat540nmcorrespondingtothe5S2/5F4→5I8transitionsofHo3+.Moreover,theUCmechanismsofHo3+/Yb3+co-dopedCaF2nano-particlesarealsodiscussed.
简介：Fe2O3/activecarbon(Fe2O3/AC)nanocompositeswerereadilyfabricatedbypyrolyzingFe3+impregnatedactivecarboninanitrogenatmosphere.Theas-preparedcompositeswerestudiedbyX-raypowderdiffraction(XRD),X-rayphotoelectronspectroscopy(XPS)andtransmissionelectronmicroscopy(TEM).Thecapacitivepropertyofthecompositeswasinvestigatedbycyclicvoltammetry(CV)andgalvanostaticcharge-dischargetest.Physicalcharacterizationsshowthattheγ-Fe2O3finegrainsdispersedintheACwell,withameansizeof21.24nm.Electrochemicaltestsin6mol/LKOHsolutionsindicatethattheas-preparednanocompositesexhibitedimprovedcapacitiveproperties.Thespecificcapacitance(SC)ofFe2O3/ACnanocompositeswasupto188.4F/gthatwasderivedfrombothelectrochemicaldouble-layercapacitanceandpseudo-capacitance,whichwas78%largerthanthatofpristineAC.AsymmetriccapacitorwithFe2O3/ACnanocompositesaselectrodeshowedanexcellentcyclingstability.TheSCwasonlyreducedbyafactorof9.2%after2000cyclesatacurrentdensityof1A/g.
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：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：ThecomplexK3H4GeW9V3O40·8H2OcrystallizedinamonocliiniesystemwithspacegroupP2,Mr=2784.67,a=11.099（3）,b=16.452（4）,c=13.534（4）,β=108.14°,Z=2,V=2348.493,F（000）:2456,μ=239.7cm-1,De=3.932g/cm3.ThefinalR=0.083for4528non-zeroreflexions.ThestructureofanionsGeW9V3O40andGeW9O34belongstoA--type.
简介：研究了ＹＢａＣｕ３Ｏ６～７超导催化剂上ＣＯ２的加氢制醇反应。考察了温度、压力和空速等条件对催化剂反应性能的影响。反应的主要产物是甲醇、ＣＯ和少量甲醚。利用ＸＰＳ、ＸＲＤ和ＡＦＭ等技术对催化剂的结构、铜的存在状态和反应活性位进行表征发现，在反应过程中，ＹＢａ２Ｃｕ３Ｏ６～７由ｏｒｔｈｏｍｂｉｃ相转变为ｔｅｔｒａｇｏｎａｌ相。反应活性位可能是Ｃｕ（Ｉ）物种。反应后催化剂颗粒的分散程度明显提高
简介：NewrareearthvanadatesYSrQ-xCaxV3O9-y（x=0.0,0.67,1.0,1.33and2.0）havebeensynthesizedbyanewsimplemethod.X-raypowderdiffractionresultsshowthattheyaremono-phase.Theybelongtoorthorhombicstructureandtheirlatticeconstantsarecalculated.TheresultsofweightgainsinTGcurvesshowthatthelowervalentvanadiumisoxidizedtohighervalentstateathighertemperature.Theoxygencontentsofnewcompoundsarecalculatedfromtheweightgains.BothV3+andV4+coexistinYSr2-xCaxV3O9-y.Thesecompoundsexhibitlowelectricresistivityatroomtemperature.
简介：Thetetranuclearalkyltin(Ⅳ)compounds{[R2Sn(C9H8N3O3)O]SnR3}2[R=n-Bu(1),4-CNC6H4CH2(2),C6H5CH2(3),4-ClC6H4CH2(4)]werepreparedbythereactionofSchiffbaseligandpyruvicacidisonicotinylhydrazonewith(R3Sn)2Ointhecorrespondingmolarratioof1:1.Allcompoundshavebeencharacterizedbyelementalanalysis,IRand^1HNMRspectra.Thecrystalstructureofcompound1wasdeterminedbyX-raysinglecrystaldiffractionalanalysis.Thiscompoundexhibitsadimericstructurecontainingdistannoxaneunitswithtwotypesofthetinatoms.Forthefirsttinatom,itappearstobeseven-coordinatedwithadistortedpentagonalbipyramidgeometry,andtheotherisfive-coordinatedwithadistortedtrigonalbipyramidalgeometry.Themoleculesarepackedintheunitcellintwo-dimensionalnetworkstructurethroughaninteractionbetweentheNatomsofthepyridineandthetinatomsofanadjacentmolecule.
简介：DBUH-Br3catalyzedselectiveconversionofsulfidestosulfoxidesinthepresenceofH2O2asoxidizingagentisdescribed.Thereactionwasperformedselectivelyatroomtemperatureandrelativelyshortreactiontimes.
简介：用微波高温固相法合成了Er^3+单掺Lu2O3,Li^+与Er^3+共掺Lu2O3及Li^+,Zn^2+,Mg^2+掺杂Lu2O3∶Er^3+的荧光粉。实验表明金属离子Li^+、Zn^2+、Mg^2+、Er^3+掺杂Lu2O3,不影响Lu2O3的立方晶相。扫描电子显微镜测量表明,Li^+掺杂可以有效改善粉体的分散性和形貌,Li^+,Zn^2+,Mg^2+共掺杂获得的粉体颗粒分布更加均匀,粒径范围为80~100nm。379nm激发下,Li^+与Er^3+共掺样品发光较单掺Er^3+样品在565nm处的发光增强了4.5倍,而Li^+、Zn^2+、Mg^2+与Er^3+共掺样品较其发光增强5.3倍。980nm激发下,Li^+与Er^3+共掺样品,Li^+、Zn^2+、Mg^2+与Er^3+共掺样品的发光分别比单掺Er^3+样品在565nm处发光增强23倍与39倍,在662nm处发光强度分别增强20倍与43倍。379nm激发下,较单掺Er3+的样品,掺杂Li^+的样品和Li^+,Zn^2+,Mg^2+和Er^3+共掺的样品荧光寿命均有所增加,而Zn^2+、Er^3+共掺及Mg^2+、Er^3+共掺样品的荧光寿命则有所缩短。
简介：Anewμ3-Otriiron（Ⅲ）complex[Fe3O（OBz）6（CH3OH）3]（NO3）（CH3OH）2（HOBZ=benzoicacid）hasbeensynthesized,itsstructurehasbeendeterminedandvariabletemperaturemagneticsusceptilityhasalsobeenmeasured.Inthemolecule,threeironatomsformedanequilateraltrianglewithu3-Oincenter.ThefittingtothemagneticsusceptibilityshowedthatanintramolecularantiferromagneticexchangeinteractionoccurredbetweenironatomswithJ=-25.51cm-1,andaweakerintermolecularantiferromagneticexchangeinteractionoccurredwithzJ’=-2.30cm-1.
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![Imidazole Coordinated Sandwich-type Antimony Polyoxotungstates Na9[ {Na（H=<b style='color:red'>O</b><b style='color:red'>2</b>}<b style='color:red'>3</b>{M（C<b style='color:red'>3</b>H4N<b style='color:red'>2</b>）}<b style='color:red'>3</b>（ Sb W9<b style='color:red'>O</b>33）<b style='color:red'>2</b>]·xH=<b style='color:red'>O</b>（M=Ni^Ⅱ, Co^Ⅱ, Zn^Ⅱ, Mn^Ⅱ）](/image/thesis2 "Imidazole Coordinated Sandwich-type Antimony Polyoxotungstates Na9[ {Na（H=<b style='color:red'>O</b><b style='color:red'>2</b>}<b style='color:red'>3</b>{M（C<b style='color:red'>3</b>H4N<b style='color:red'>2</b>）}<b style='color:red'>3</b>（ Sb W9<b style='color:red'>O</b>33）<b style='color:red'>2</b>]·xH=<b style='color:red'>O</b>（M=Ni^Ⅱ, Co^Ⅱ, Zn^Ⅱ, Mn^Ⅱ）")
![Synthesis and Characterization of Tetranuclear Alkyltin（Ⅳ）Compounds with Schiff Base Ligand Pyruvic Acid Isonicotinyl Hydrazone and Crystal Structure of {[^nBu<b style='color:red'>2</b>Sn（C9H8N<b style='color:red'>3</b><b style='color:red'>O</b><b style='color:red'>3</b>）<b style='color:red'>O</b>]SnBu<b style='color:red'>3</b>^n}<b style='color:red'>2</b>](/image/thesis15 "Synthesis and Characterization of Tetranuclear Alkyltin（Ⅳ）Compounds with Schiff Base Ligand Pyruvic Acid Isonicotinyl Hydrazone and Crystal Structure of {[^nBu<b style='color:red'>2</b>Sn（C9H8N<b style='color:red'>3</b><b style='color:red'>O</b><b style='color:red'>3</b>）<b style='color:red'>O</b>]SnBu<b style='color:red'>3</b>^n}<b style='color:red'>2</b>")
![The structure and magnetic properties of μ<b style='color:red'>3</b>-oxotriiron（Ⅲ） complex [Fe<b style='color:red'>3</b><b style='color:red'>O</b>（OBz）6（CH<b style='color:red'>3</b>OH）<b style='color:red'>3</b>]（NO<b style='color:red'>3</b>）（CH<b style='color:red'>3</b>OH）<b style='color:red'>2</b>](/image/thesis18 "The structure and magnetic properties of μ<b style='color:red'>3</b>-oxotriiron（Ⅲ） complex [Fe<b style='color:red'>3</b><b style='color:red'>O</b>（OBz）6（CH<b style='color:red'>3</b>OH）<b style='color:red'>3</b>]（NO<b style='color:red'>3</b>）（CH<b style='color:red'>3</b>OH）<b style='color:red'>2</b>")
