学科分类
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239 个结果
  • 简介:AseriesofRbxCs1-xAg4I5(x=0-1)thinfilmsweregrownbyvacuumevaporationonNaCIcrystalsubstratesat350K.Theabsorptionspectraofthesefilmsweremeasuredat80Kinthewavelengthrangefrom240nmto400nm.ItisshownthatsuperionicconductorthinfilmsofquaternarycompoundRb0.5Cs0.5Ag4I5andternarycompoundRbAg415canbeobtainedatx=0.5-0.6andx=0.7-1,respectively.Atx=0.65,thecombinedcompoundfilmofthemixtureof30mol%RbAg4I5and70mol%Rb0.5Cs0.5Ag4I5ispresented.Then,basedonthespectralpositionsoftheA1andA2peaks,wedeterminedthattheRb0.5Cs0.5Ag4I5excitoncouplingenergyRexis0.21eV,theforbiddenzonewidthEgis3.82eVandtheexcitonradiusaexis0.70hm.Furthermore,theionicconductivitiesofsuperionicconductorthinfilmsofRbAg4I5andRb0.5Cs0.5Ag4I5andtheirmixturefilmareinvestigated,respectively,inthetemperaturerange303K-393K.

  • 标签: 吸收光谱 离子传导性 超离子导体薄膜 真空演化
  • 简介:Aserialofprotonatedandlayeredtransitionmetaloxides,includinglayeredHTaWO6,HNbMoO6aswellasHNbWO6,weresynthesizedbysolid-statereactionandion-exchange.ThelayeredHTaWO6hasbeensystematicallystudiedasasolidacidtorealizethedehydrationoffructoseto5-hydroxymethylfurfural(HMF).ThetransitionmetaloxidesampleswerecharacterizedwithICP-OES,EDS,XRD,XPS,SEM,TGA,FT-IR,N2adsorption–desorptionandNH3-TPD.Theinfluentialfactorssuchasreactiontemperature,reactiontime,solvent,catalystamountandsubstrateconcentrationweredeeplyinvestigated.Theoptimizedfructoseconversionrateof99%withHMFyieldof67%wereachievedafter30minat140°Cindimethylsulfoxide.

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  • 简介:利用基于密度泛函的第一性原理对Zr5Te3化合物晶格常数、形成焓、弹性常数、以及电子态密度等性质进行了计算。在该研究中,为了获得Zr5Te3化合物的结构稳定性,考虑了Cr5B3、W5Si3以及Mn5Si3等三种结构类型,计算的形成焓表明:具有Cr5B3结构类型的Zr5Te3最稳定,其次是Mn5Si3型,最后才是W5Si3型。也对该化合物的电子态密度和电荷密度差进行了计算,利用徳拜模型计算了其在高温高压下的体积、体积模量、热熔以及热膨胀等的热物理性质。

  • 标签: 热物理性质 弹性性质 电子结构
  • 简介:Linearpolysiloxaneswithpendantbenzo-15-crown-5moietieshavebeensynthesizedfrom3′-or4′-allylbenzo-15-C-5viahydrosilylationofmethyldichlorosilane,followedbypolycondensationwithsilanol-terminatedpolydimethylsiloxane.Itwasfoundthatthepolysiloxanescouldbeusedascarriersinbulkliquidmembranetotransportions.Factorsinfluencingtransportratehavebeeninvestigated.

  • 标签: 合成 线性聚硅氧烷 苯并-15-冠醚-5 液膜
  • 简介:Ourobjectivesweretodevelopanewchemicalmethodforthepolymerizationofpyrrole.CuCl2dissolvedinC2H5OHsolventisprimarilyusedfortheinitiationpolymerizationofpyrrole.ThepolymerswithdifferentyieldandconductivitywereobtainedbyraringtheinitialconcentrationofCu2+.TheinitialconcentrationsofCu2+variedfrom1.2×10-4moleto6.48×10-3moleCu2+with2.16×10-2molepyrrole.Thepolypyrroleobtainedwascharacterizedwithelementalanalyzer,XPS,IRspectroscopy,Four-pointprobeandSEM.

  • 标签: CuCl2-C2H5OH initiation SYSTEM Polymerization of PYRROLE
  • 简介:采用自洽场离散变分Xa(SCC-DV-Xa)方法对纯V2O5及夹层V2O5的能带结构、态密度、键强度、电子集居数等进行了研究.结果表明,Li+引入V2O2层间的最佳位置是在双键氧之下(或之上),且靠近层的中心位置,此时它与周围原子间的作用力非常微弱,并且材料的导电性增强,使夹层复合材料Li+注入/脱出具有很好的可逆性和较好的光学性质.

  • 标签: PEO 夹层复合材料 掺杂位置 电子结构 五氧化二钒 锂离子
  • 简介:Inthiswork,aseriesofMIL-101-SO3H(x)polymericmaterialswerepreparedandfurtherusedforthefirsttimeasefficientheterogeneouscatalystsfortheconversionoffructose-basedcarbohydratesinto5-ethoxymethylfurfural(EMF)inarenewablemixedsolventsystemconsistingofethanolandtetrahydrofuran(THF).Theinfluenceof–SO3HcontentontheacidityaswellasonthecatalyticactivityoftheporouscoordinationpolymersinEMFproductionwasalsostudied.HighEMFyieldsof67.7%and54.2%couldbesuccessivelyobtainedfromfructoseandinulininthepresenceofMIL-101-SO3H(100)at130°Cfor15h.Thecatalystcouldbereusedforfivetimeswithoutsignificantlossofitsactivityandtherecoveryprocesswasfacileandsimple.Thisworkprovidesanewplatformbyapplicationofporouscoordinationpolymers(PCPs)fortheproductionofthepotentialliquidfuelmoleculeEMFfrombiomassinasustainablesolventsystem.

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  • 简介:Removalofcarbonylsulfide(COS)fromCO2streamissignificantfortheproductionandutilizationoffoodgradeCO2.ThisstudyinvestigatestheadsorptionperformanceofAg/NaZSM-5asadsorbentpreparedbyincipientwetnessimpregnationfortheremovalofCOSfromaCO2streaminafixed-bedadsorptionapparatus.Effectsofvariousconditionsonthepreparationofadsorbent,adsorptionanddesorptionwereintensivelyexamined.TheresultsrevealedthatCOScanberemovedtobelow1×10-9fromaCO2stream(1000ppmCOS/CO2)usingAg/NaZSM-5(10wt%AgNO3)withanadsorptioncapacityof12.86mg·g-1.Theadsorbentcanbefullyregeneratedusinghotairat450C.Theadsorptionabilityremainedstableevenaftereightcyclesofregeneration.

  • 标签: CARBONYL SULFIDE adsorption π-complexation COMPLETELY regeneration
  • 简介:Ahomologousseriesof4’-methylphenyl4"-[(4-alkoxy-2,3,5,6-tetrafluorophenyl)ethynyl]-benzoateshavebeensynthesized.Polarizingmicroscopictexturalobservationshowsthatsuchcompoundsexhibitenantiotropicnematicphase.

  • 标签: Liquid crystal 1 4-tetrafluorophenylene SYNTHESIS NEMATIC
  • 简介:采用荧光光谱法研究了水溶液中四溴荧光素、四氯四溴荧光素、二碘荧光素、乙基罗丹明B、健那绿B等5种荧光染料探针与牛血清白蛋白(BSA)的相互作用.实验表明,这5种染料探针同牛血清白蛋白结合时,疏水作用力起决定性作用,静电力起次要作用,相比之下牛血清白蛋白(BSA)结合阴离子的能力最强,其次为中性分子,最后为阳离子.通过疏水作用力,5种染料均是以非极性苯基进入BSA疏水性腔体中同色氨酸残基发生作用,弱氢键的形成加强了这种作用力,且使得光谱间能量转移效率明显提高.5种染料探针的极性部位由于极性和空间效应的原因难以进入腔体内部,致使反应均按接近1∶1的方式进行.

  • 标签: 荧光染料探针 牛血清白蛋白 荧光 反应机理
  • 简介:Fractionalpyrolysisandone-steppyrolysisofnaturalalgaeCyanobacteriafromTaihuLakewerecomparativelystudiedfrom200to500°C.One-steppyrolysisproducedbio-oilwithcomplexcompositionandlowhighheatingvalue(HHV30.9MJ/kg).FractionalpyrolysisseparatedthedegradationofdifferentcomponentsinCyanobacteriaandimprovedtheselectivitytoproductsinbio-oil.Thatis,acidsat200°C,amidesandacidsat300°C,phenolsandnitrilesat400°C,andphenolsat500°C,weregotasmainproducts,respectively.HZSM-5couldpromotethedehydration,crackingandaromatizationofpyrolyticintermediatesinfractionalpyrolysis.AtoptimalHZSM-5catalystdosageof1.0g,theselectivitytoproductsandthequalityofbio-oilwereimprovedobviously.Themainproductsinbio-oilchangedtonitriles(47.2%)at300°C,indoles(51.3%)andphenols(36.3%)at400°C.Theoxygencontentwasreducedto7.2wt%and9.4wt%,andtheHHVwasraisedto38.1and37.3MJ/kgat300and400°C,respectively.Fractionalcatalyticpyrolysiswasproposedtobeanefficientmethodnotonlytoprovideapotentialsolutionforalleviatingenvironmentalpressurefromwaterblooms,butalsotoimprovetheselectivitytoproductsandobtainhighqualitybio-oil.

  • 标签: HZSM-5催化剂 蓝藻水华 生物油 热解 品质 小数
  • 简介:Theorientationoftheadditionof5-amino-3-benzylthio-1,2,4-triazoleanditsanalogues(pyrazole)(1)withthearylisocyanatecanbedirectedbycontrollingthereactiontemperatureandoneoftheproduct,5-amino-1-arylaminocarbonyl-3-benzylthio-1,2,4-triazole(pyrazole)(2),canrearrangeat170Ctoanotherproduct,5-arylureylene-3-benzylthio-1,2,4-triazole(pyrazole)(3).Aplausiblemechanismexplanationforthisrearrangementreactionwaspresented.Itwassuggestedthattherearrangementreactioncouldbereferredtothethermodynamicstranspositionleadingtothepredominant5-arylureylene-3-benzylthio-1,2,4-triazoleenergypreferentially.

  • 标签: 1 2 4-Triazole ary ISOCYANATE REARRANGEMENT
  • 简介:在这个工作,它被介绍任务的应用象对3-amino-5-aryl-2,5-dihydropyridazines的合成的可溶的支持咸的特定的onium。这可溶的支持具有宽适用性并且没有它的限制,溶液阶段化学把稳固的阶段合成的优点与那些相结合。在一个简单的洗步骤以后,产品从支持被劈开并且在好收益获得了。

  • 标签: 固相合成 可溶性 氨基 芳基 鎓盐 适用性
  • 简介:Halfsandwichirondicarbonylcomplex[η5-C5H3(t-Bu)2]Fe(CO)2Cl(1)reactswith1,2-dilithiumdiselenocarboraneLi2Se2C2B10H10(2)togiveabinuclearironcarboranecomplex[η5-C5H3(t-Bu)2]2Fe2(CO)3*Se2C2B10H10(3).TheX-raydiffractionanalysisofcomplex3revealsthatoneoftheironatomsischiral.

  • 标签: Carborane Halfsandwich IRON complex Chirality Molecular