简介：Inthiswork,boththethermalexpansionandelectricalconductivityofnanocrystallineLa2Mo2O9werestudied.ThenanocrystallinepowderofLa2Mo2O9wasobtainedbysol-gelmethod,andwiththehelpofSHP(superhighpressure)upto4.5×104atmat700℃forashorttime,andthenanocrystallinepowderwasdensifiedwithoutobviousparticlesizegrowth.TheelectricalconductivityofnanocrystallineLa2Mo2O9wasoneorderofmagnitudelowerthanthatofthemicrocrystallinesampleatthesametemperature.Owingtothephasetransition,themicrocrystallineLa2Mo2O9hasanabruptincreaseofthermalexpansionwithapeakvalueof48×10-6K-1at556℃.Forthenanocrystallinematerial,thepeakvalueincreasesto112×10-6K-1at520℃.Ontheotherhand,above600℃thesignificantgrowthofparticlesizeofthenanocrystallineLa2Mo2O9wasobserved,accompanyingbyatremendousincreaseofthermalexpansionwithapeakvalueofthirdhigherthanthatofLa2Mo2O9.
简介：TheextractionofCe(Ⅳ)inH2SO4/H3PO4systemwasinvestigatedsystematicallyusingbifunctionalionicliquidextractants(Bif-ILES)[A336][P507],[A336][P204]and[A336][C272]inn-heptane.TheeffectsofH2SO4concentration,extractantconcentrationandsalting-outagentconcentrationwereobservedindetail.TheextractionmechanismofCe(Ⅳ)inH2SO4/H3PO4systemwasobtained.ThecomparisonwithotherextractantssuchasCyanex923,TBPwasalsostudied.Thermodynamicfunctionsoftheextractionreactionwerecalculated,showingthattheextractionwasanexothermicprocess.TheseparationofCe(Ⅳ)fromRE(Ⅲ)andTh(Ⅳ)wasalsoinvestigated.TheresultindicatedthatCe(Ⅳ)couldbeselectivelyextractedinthissystem.CePO4nanoparticleswereobtainedintheprocessofstrippingusingH2O2inH2SO4/H3PO4system.X-raydiffraction(XRD),scanningelectronmicroscopy(SEM)andspectroscopywereadoptedforthecharacterizationofthesample.
简介：Reactionof(MeC5H4)3LnwithHOCH2CH2NMe2intetrahydrofuran(THF)givesthenewcomplexes[(MeC5H4)2Ln(μ-OCH2CH2NMe2)]2(Ln=Sm,Y,Nd)withnitrogenfunctionalizedμ-alkoxideligand.ThecomplexeswerecharacterizedbyelementalanalysisandIR,and[(MeC5H4)2Sm(μ-OCH2CH2NMe2)]2wasstructurallycharacterizedbytheX-raydiffractiontobeadimerformedbytwounsymmetricoxygenbridges.ThecomplexhasatricyclicskeletonwiththeadditionaltwoSm-NbondsviaintramolecularcoordinationofOCH2CH2NMe2.ThecoordinationnumberofthecentralmetalSmisnine.Thetitlecomplexesshowgoodcatalyticactivityforring-openingpolymerizationofε-caprolactone.
简介：DirectextractionofmetalsfromsolidswithcomplexingagentsinsupercriticalCO2(SC-CO2)hasrecentlyattractedinterestsinseparation,purification,recovery,andanalysisofmetals.Inthepresentstudy,thestatic/dynamicextractionofrareearthelements(Nd,Ce)fromtheiroxides(Nd2O3,CeO2)withorganophosphoruscomplexeswithHNO3andH2OinSC-CO2wasinvestigated.ThestaticextractionefficiencyofNdfromNd2O3withthetri-n-butylphosphate(TBP)-HNO3complexcouldreach95%underoptimizedexperiment...
简介：
简介：Forthegoalofsulfurrecovery,mostmethodsareaimedatthetailgaswithhigh-concentrationH2S,butfeweffectivemethodsareusedforlow-concentrationH2S.Inthiswork,Low-concentrationH2Scouldbepurifiedwellbyliquidphasecatalyticoxidation(LCO),andthesulfurresourcecouldalsoberecovered.TheabsorptionsolutionwaspreparedbyFeCl3andsulfosalicylicacid.Undertheexperimentalconditions,theconversionofH2StoScouldbemaintainedabove94%at60℃.InordertoenhancetheeconomicalefficiencyofLCOmethod,theabsorptionsolutionwasmodifiedbydopingCe,andaseriesofexperimentsweredesignedtoinvestigateitsperformance.TheresultsshowedthattheconversionofH2Shadnoobviousimprovement,butabove98%conversioncouldbegainedat60℃,andtheH2Sconversionratewasenhanced.TheoptimumadditionqualityofCe(NO3)3was0.08gto50mlFe3+solution.
简介：ThereactionofNdCl3withlithiummethylnaphthalenein1:2moleratioinTHFgeneratesblackpowder.Thepowderreactswithcyclooctatetraene（COT）inTHFtoformthetitlecomplex.[Li（THF）4Nd（C8H8）2]·2THFcrystallizesinthemonoclinicspacegroupP2/cwithunit-celldimensionsa=1.7858（7）nm,h=1.3243（4）nm,c=1.8086（6）nm.β=106.52（4）°,V=4.10nm3andDc=1.268g/cm3forZ=4.F（000）=1660,R=0.0774,Rn=0.0733.Thecomplexconsistsofdiscreteion-pairandtwoTHFmoleculesadduct.Intheanion,theneodymiumatomiscoordinatedbytwoCOTrings.ThestructureofthecationshowsthatthelithiumatomisattachedwithTHFmoleculesonly.
简介：Thesinglecrystalofthecomplex[Sc（NO3）3（H2O）2]·（15C5）hasbeenpreparedinacetonitrile.Thenewcomplexhasbeencharacterizedbyelementalanalysis,IRspectra,solubilityandmolarconductancemeasurements.ThestructureofthecomplexisdeterminedbysinglecrystalX-raydiffractionanalysis.
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。
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![Synthesis and crystal structure of a novel double 1：11 series arsenotungstate： [Cu^I（phen）<b style='color:red'>2</b>]5<b style='color:red'>H</b>6[Sm（AsW11O39）<b style='color:red'>2</b>]·6<b style='color:red'>H</b><b style='color:red'>2</b>O](/image/thesis3 "Synthesis and crystal structure of a novel double 1：11 series arsenotungstate： [Cu^I（phen）<b style='color:red'>2</b>]5<b style='color:red'>H</b>6[Sm（AsW11O39）<b style='color:red'>2</b>]·6<b style='color:red'>H</b><b style='color:red'>2</b>O")
![Synthesis, Crystal Structure of [ （MeC5<b style='color:red'>H</b>4）<b style='color:red'>2</b>Ln（μ-OCH<b style='color:red'>2</b> CH<b style='color:red'>2</b>NMe<b style='color:red'>2</b> ） ]<b style='color:red'>2</b> （Ln = Sm, Y, Nd） and Their Catalytic Activity for Ring-Opening Polymerization of ε-Caprolactone](/image/thesis5 "Synthesis, Crystal Structure of [ （MeC5<b style='color:red'>H</b>4）<b style='color:red'>2</b>Ln（μ-OCH<b style='color:red'>2</b> CH<b style='color:red'>2</b>NMe<b style='color:red'>2</b> ） ]<b style='color:red'>2</b> （Ln = Sm, Y, Nd） and Their Catalytic Activity for Ring-Opening Polymerization of ε-Caprolactone")
![Synthesis and Crystal Structure of a Novel Ion-pair Complex of [Li（THF）4Nd（C8<b style='color:red'>H</b>8）<b style='color:red'>2</b>]·<b style='color:red'>2</b>THF](/image/thesis9 "Synthesis and Crystal Structure of a Novel Ion-pair Complex of [Li（THF）4Nd（C8<b style='color:red'>H</b>8）<b style='color:red'>2</b>]·<b style='color:red'>2</b>THF")
![STUDIES ON RARE EARTH COMPLEXES WITH CROWN ETHERS ⅩⅧ——Synthesis,Characterization and Crystal Structure of[Sc（NO3）3（<b style='color:red'>H</b><b style='color:red'>2</b>O）<b style='color:red'>2</b>]·（15-Crown-5）](/image/thesis12 "STUDIES ON RARE EARTH COMPLEXES WITH CROWN ETHERS ⅩⅧ——Synthesis,Characterization and Crystal Structure of[Sc（NO3）3（<b style='color:red'>H</b><b style='color:red'>2</b>O）<b style='color:red'>2</b>]·（15-Crown-5）")
