简介:用柠檬酸溶胶-凝胶工艺制备出了LiV3O8化合物,并检测了其作为热电池阴极材料时的放电性能,干凝胶210℃焙烧所得的粉末颗粒疏松多孔,300℃时可变成结晶岩状,低温焙烧时出现了Li0.3V2O5和LiV2O5相,经650℃长时间保温后可转变为LiV3O8,模拟Li-B/LiCl-KCl/LiV3O8(或V2O5)热电池500℃放电试验表明,LiV3O8因具有良好的电子导电体和较低的Li+扩散极化,其放电较V2O5平稳,虽峰值电压略有降低,但可利用的比容量(电压降至峰值电压的75%或2.0V)均不低于V2O5;LiV3O8中掺入8%的P2O5时可提高小电流放电时的电压。
简介:Thesolidaddofthefirstprotonatedzincoborophosphate,(H3O)Zn(H2O)2BP2O8·H2O(1),wassoventothermallysyn-thesizedbythereactionofZn(NO3)2·6H2OandH3BO3withH3PO4inamixedsolvent,andstructurallycharacterizedbysingle-ystalX-raydiffractionanalysis.ItcrystallizesinthehexagonalP6122,a=0.9604(4)nm,c=1.5297(6)nm,V=1.2218(8)nm^3,Dc=2.921g/cm^3,Z=6,F(000)=1080,μ=3.495mm^-1.Thestmchwefeaturesthatthetetrahedra-te-trahedrahdlcesinterconnectedbyoctahedraandstronghydro-gembondinteractionsformathree-dimensionalframework.Theprotonatedwatermoleculesarelocatedatuniquepositions.othercharacterizationsbyIRandthermalanalysisarealsode-scribed.
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:以环己酮、乙二醇为原料,自制的锑铁复合固体超强酸S2O8^2-/Sb2O3/Fe2O3作催化剂,合成了环己酮乙二醇缩酮。通过分析环己酮与乙二醇的摩尔比、催化剂的量、反应时间和带水剂的用量对环己酮乙二醇缩酮的产率的单因素影响,选出合成环己酮乙二醇缩酮的单因素最优方案。同时,以环己酮与乙二醇的摩尔比、催化剂的量、带水剂的用量和反应时间为因素,设计了L9(34)正交表进行实验,得出的正交试验最佳方案为A2B1C2D2,即环己酮与乙二醇的摩尔比为1.0:1.7,催化剂的量为1.0g,带水剂用量为8mL,反应时间为1.5h。在该方案下,环己酮乙二醇缩酮的产率可以达到83.69%。
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:层状结构材料Li1+xV3O8有可能成为新一代锂离子电池正极材料。综述了锂离子电池正极材料的结构特点,重点介绍了国内外Li1+xV3O8的几种合成方法,分析了Li1+xV3O8的掺杂改性研究,总结了正极材料Li1+xV3O8的充放电工作原理,并展望了锂离子电池正极材料Li1+xV3O8未来应用前景。
简介:Pureandneodymium-dopedgadoliniumcalciumoxoboratecrystalsofhighqualityweregrownbytheCzochralskimethod.Theorientationofcrystalwaspreciselydetermined,andthesamplesformeasurementswereprepared.Throughsynchrotronx-raytopographyandhigh-resolutionx-raydiffractometry,thetwinstructurewasdiscovered.Somepropertiessuchasthefigureofmeritvalue,anddielectric,piezoelectric,andelasticconstantsweremeausuredalongwithadiscussionoftheanisotropyofthelaserproperties.
简介:Organicmultiplequantumwells(OMQWs)consistingofalternatinglayersoforganicmaterialshavebeenfabricatedfromtris(8-hdroxyquinoline)aluminum(Alq)and2-(4-biphenylyl)-5-(4-tertbutylphenyl)-1,3,3-oxadiazole(PBD)byamultisource-typehigh-vacuumorganicmoleculardeposition.Fromthesmall-angleX-raydiffractionpatternsofAlq/PBDOMQWs,aperiodicallylayeredstructureisconfirmedthroughtheentirestack.TheAlqlayerthicknessintheOMQWswasvariedfrom1nmto4nm.Fromtheopticalaborption,photoluminescenceandelectroluminescencemeasurements,itisfoundthattheexcitonenergyshiftstohigherenergywithdecreasingAlqlayerthickness,ThechangesoftheexcitonenergycouldbeinterpretedastheconfinementeffectsofexcitonintheAlqthinlayers.Narrowingoftheemissionspectrumhasalsobeenobservedfortheelectroluminescentdevices(ELDs)withtheOMQWsstructureatroomtemperature.
简介:本文制备了Bi2O3-Ni2O3纳米粉末,对其结构进行了表征,并研究了制备的纳米粉末对苯光催化降解的影响因素。结果表明:制备的纳米粉末由Bi2O3和Ni2O3复合而成,经750℃焙烧的光催化剂对苯光催化降解活性最高;水蒸气的加入和氧气的增加,都能促进苯的降解率增大;由Langmuir-Hinshelwood动力学模型得出苯的光催化降解反应的吸附常数和反应速率常数分别为0.1398L·μmol^-1和0.0024μmol·L-1·min^-1。
简介:Throughmeasuringthecoefficientoflinearexpansion,thestructureandpropertiesoftheLi2O-Al2O3-SiO2lowexpansionglassceramicscontainingB2O3arestudiedbyJRandXRD.ItisshoutnthattheIRmethodisefficientinthestudyoftheglass-ceramicsstructure.Thereisa"Boronabnormality"inthesystemwhichhasanimportantinfluenceonthepropertiesoftheglass-ceramics.
简介:TheZrO2-Al2O3ceramiccompositeswerepreparedbyappropriatetechniqueswithcommercialZrO2andAl2O3powdersasrawmaterialsandY2O3asstabilizer.TheresultsindicatethatwiththeintroductionofAl2O3intotheZrO2matrixwherethequantityofadditiveY2O3is3.5%(molefraction),thegrowthofZrO2grainsisefficientlyinhibited,whichhelpstheZrO2grainsexistinametastabletetragonalmanner;thushigherstrengthandtoughnessareacquired.Whenthecontentofaluminais20%(massfraction),thebendingstrengthandfracturetoughnessofthecompositesare676.7MPaand10MPa·m1/2respectively,themechanicalbehaviorsareclosetothosepreparedwithZrO2andAl2O3powderssynthesizedthroughwetchemicalapproach.Themechanicalbehaviorsofthecompositesarewellimprovedowingtothedispersiontougheningofaluminagrainsandphasetransformationtougheningofzirconiagrains.
简介:MgO-Al2O3-Cr2O3rammingmixesmadeofdifferentrawmaterialshavedifferentmineralstructureanddifferentphysicalpropertiesthoughwiththeidenticalparticlesizedistribution,thesameamountofbinderandchemicalcomposition.Theresidualcarboncontentofthefusedmagnesia-chromematerialmadeinreducingatmosphereisveryhigh,ifthismaterialsisusedintheMgO-Al2O3-Cr2O3rammingmix,itwouldcausespallingofthefurnaceliningduringdrying-out.