学科分类
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58 个结果
  • 简介:SpectralParameterStudyonTm3+inNaTm(WO4)4CrystalYaoLianzeng(姚连增)(DepartmentofMaterialsScienceandEnginering,UniversityofScienc...

  • 标签: Rare earths NA 5Tm(WO 4) 4
  • 简介:Loadedonthecordierite,therareearthdopedcompositecatalystwaspreparedbysol-gelmethodcombinedwithdippingtechnique.TakingOrthodichlorobenzeneasmodel,thecatalystwasusedtoremovethedioxinsofthewastegas.Theresultsshowedthatat280℃andgasspacevelocitybeing8000h-1,theorthodichlorobenzenecouldberemovedeffectivilybythepreparedCeO2-TiO2-V2O5compositecatalystwhoseactivitywasremarkablyenhancedbythedopingofCe,whiletheindustrialside-streamtestofdioxinsfromrefuseincinerationsmokeindicatedthatthedecompositionratecouldreachabove93%underthesameconditions.

  • 标签: orthodichlorobenzene DIOXINS CATALYTIC oxidation REFUSE INCINERATION
  • 简介:TheeffectofrapidsolidificationonstructureandelectrochemicalperformanceoftheLaNi4.5Co0.25Al0.25hydrogenstoragealloywasinvestigatedbyX-raypowderdiffractionandasimulatedbatterytest,includingmaximumcapacity,cyclingstability,self-discharge,andhigh-ratedischargeability(HRD).Allthemelt-spunalloysweresingle-phasewiththeCaCu5-typestructure(spacegroupP6/mmm).Incomparisontotheas-castalloy,therapidlyquenchedalloysmanifestedanimprovedhomogeneityofcompositionandexpandedlatticeparameters.Theelectrochemicalmeasurementsshowedthattheactivationproperty,cyclingstabilityandself-dischargeofthealloyelectrodeswerealsoimprovedfortherapidsolidifiedalloys.TheHRDoftheas-castalloywasbetterthanthoseofalltherapidlysolidifiedalloys.Asthequenchingrateincreased,theHRDandexchangecurrentdensityfirstdecreasedandthenincreased.

  • 标签: AB5型贮氢合金 电化学性能 快速凝固 结构 X射线粉末衍射 循环稳定性
  • 简介:Thephasesandmagnetocaloriceffectinthealloys(Gd1-xErx)5Si1.8Ge2.2withx=0,0.1,0.2and0.3wereinvestigatedbyX-raydiffractionanalysisandmagnetizationmeasurement.ThesamplesweresinglephasewiththemonoclinicGd5Si2Ge2-typestructure.WiththeincreaseofErcontent,theCurietemperature(Tc)decreasedobviouslyfrom253Kofthealloywithx=0to114Kwithx=0.3.Themaximummagneticentropychangedinthesamplesof(Gd1-xErx)5Si1.8Ge2.2withx=0.0,0.1,0.2and0.3were6.88,8.32,9.59and10.24J·kg-1·K-1respectivelyintheappliedfieldchangeof0~2.0T.

  • 标签: (Gd1-xErx)5Si1.8Ge2.2 compounds MAGNETOCALORIC effects magnetic entropy
  • 简介:Er3+/Yb3+codopedzincateBaGd2ZnO5phosphorsweresynthesizedviaatraditionalsolidstatereaction.ThecrystalstructureandphasepuritywerecheckedbymeansofX-raydiffraction(XRD),andtheresultsshowedthatpurephaseBaGd2ZnO5phosphorswithvariousEr3+,Yb3+concentrationswereobtained.TheinfluenceofEr3+andYb3+dopingconcentrationsonthegreenandredupconversionemissionswasstudied.Itwasfoundthatbothgreenandredupconversionemissionsunder980nmexcitationweretwo-photonprocessesindependentfromtherareearthdopingconcentrations.However,theupconversionluminescenceintensitiesgreatlydependedontherareearthdopingconcentration.Furthermore,thepopulationprocessesofupconversionluminescenceandthequenchingmechanismswereanalyzed.Thetemperature-dependentgreenupconversionluminescencewasstudied,andthetemperaturequenchingprocessoftwogreenupconversionemissionswasmodeled.Thethermalquenchingprocessesofthegreenupconversionemissionscouldbewellexplainedbythemodelweproposed.

  • 标签: 上转换发光 温度依赖性 浓度效应 荧光粉 淬火 固相反应合成
  • 简介:8月29日,包头国家稀土高新区对外发布消息称,稀土高新区根据包头市建设稀土新材料基地的战略目标,拟用5~10年的时间,将包头建成全国最重要的稀土新材料基地。

  • 标签: 包头市 稀土 产业基地 时间 新材料 中国
  • 简介:2016年是“十三五”规划的开局之年,持续推进供给侧结构性改革,是适应和引领经济发展新常态的重大创新,是适应国际金融危机发生后综合国力竞争新形势的主动选择,是适应我国经济发展新常态的必然要求。2016年,对于稀土行业是心怀希望艰难前行的一年。随着供给侧结构性改革的持续推进,六大稀土集团全部组建完成,生产总量控制发挥着有效调节供给的作用。

  • 标签: 稀土行业 供给 改革 结构 公司业绩 企业业绩
  • 简介:ThesurfaceofacommercialY3Al5O12:Ce3+phosphorwasmodifiedby99%NH4F+CH3COOHsolutioninasupersonicbathwithwatertemperatureof80oCfor4h.Thescanningelectronmicroscopy(SEM)resultsshowedthattheedgeangleswerenotassharpastheunmodifiedparticlesandtheflatsurfacesturnedroughwithmanymicro-structurescovered.Positronlifetimemeasurementsquantitativelyshowedthatsurfacedefectswereremovedawaybymorethan50%.Asaresult,thephotoluminescencedeterminationsshowedthatthebackscatterlosswasreducedby4.2%andtheemissionpowerwasenhancedby5.6%afterthesurfacemodification.Theconversionefficiencywasgreatlyimprovedfrom47.3%to51.1%,aspresentedbythefluorescenceimages.Therefore,itwouldbegreatlyhelpfulfortheimprovementofefficiency,transparencyandstabilityofpc-LED.Moreover,thismethodwassignificantlysuitableformassproductionduetoitseasyoperationandlowcost.

  • 标签: 表面特征 表面缺陷 溶胶-凝胶法 荧光粉 选择性腐蚀 CE
  • 简介:Thesinglecrystalofthecomplex[Sc(NO3)3(H2O)2]·(15C5)hasbeenpreparedinacetonitrile.Thenewcomplexhasbeencharacterizedbyelementalanalysis,IRspectra,solubilityandmolarconductancemeasurements.ThestructureofthecomplexisdeterminedbysinglecrystalX-raydiffractionanalysis.

  • 标签: solubility acetonitrile Crown molar H2O NO3
  • 简介:采用5水平Box-Behnken设计的反应表面方法论(RSM)被用来优化铈(III)的biosorption到动物和植物起源viz的biowaste材料上。对虾甲壳(PC)和玉米风格(CS)。各种各样的过程参数viz。pH(一:3.0–9.0),生物资源剂量(B:0.05–0.35g/L),起始的金属集中(C:50–350mg/L),接触时间(D:2–6h)并且温度(E:20–60°C)为优化被选择。木头转变被盒子艇长阴谋在现在的盒子中建议。低p值<0.0001验证了模型的意义。为PC的218.3mg/g和为CS的180.2mg/g的最大的Ce(III)举起在最佳条件下面被注意。在平衡等温线之中,Freundlich模型被发现是而兰米尔模型证明最好适合在CS上建议铈biosorption的同类的模式,在PC上建议biosorption的一个异构的模式的最好适合的那个。这被扫描电子显微镜学(SEM)进一步证实。运动研究显示出作为位于这个过程下面的现象建议physisorption的伪first顺序模型的更好的适用性。电影散开被博伊德阴谋的非线性建议。热力学的研究证明这个过程吸热、自发。FTIR分析在Ce(III)biosorption期间证实了酰胺,胺,酉同类和主要白酒组的参予的主要参与。EDAX分析在Ce(III)biosorption期间证实了碳组的主要参予。这是Ce(III)biosorption的参数优化上的第一份报告到用可能从水的环境对Ce(III)的恢复有用的5水平Box-Behnken试验性的设计的biowaste材料上。

  • 标签: 物理吸附 铈(Ⅲ) 平衡等温线 参数优化 生物废料 植物来源
  • 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.

  • 标签: 2 晶体结构 合成 镧系元素 ε-已内酯 聚合