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简介：Basedonthethermodynamicallyself-consistentanalysisandoptimizationofthreesub-binarysystemsoftheternarysystemPrCl3-CaCl2-MgCl2,thethermodynamicsofthisternarysystemhasbeenstudied.UsingHillertmodelandtakingMgCl2asanasymmetriccomponent,thePrCl3-CaCl2-MgCl2phasediagramhasbeencalculated.Theagreementbetweencalculatedandmeasuredcompositionsandtemperaturesatdeflectingpointsonliquidusisgood.Thesystemisasimpleeutecticonewithaeutecticpointat26.0mol%PrCl3,41.5mol%CaCl2,32.5mol%MgCl2;560℃（calculated）and26.0mol%PrCl3,39.4mol%CaCl2,34.6mol%MgCl2;546℃（measured）,respectively.

简介：NominalcompositionofCa1-xZnxTiO3:0.002Pr3+(x=0.000～0.200)phosphorswerepreparedbyconventionalsolidreactionroute.XRDandPLmeasurementswereusedtoinvestigatethesolid-solutionstructureandluminescencepropertiesofZn-dopedCa1-xZnxTiO3:0.002Pr3+phosphors.Theeffectofsolid-solutionstructureformedbysubstitutionbetweenCa2+andZn2+ionsontheluminescentpropertieswasanalyzed.Theresultsrevealthat,withtheincreaseofZnsubstitutioncontentbelow0.010,latticeparametersandtheintensityofexcitationpeakatboth260and330nmaswellasthecorresponding610nmemissionintensityaremonotonouslydecreasedquicklyinasimilartendency.Also,theevolutionofluminescenceintensityandcrystalcellparametersagainstZndopingconcentrationareingoodagreement.AboveresultsarecloselyrelatedwiththestructurechangewithinCa1-xZnxTiO3:0.002Pr3+solid-solutionphaseformedbytheZnionssubstitutionfortheCasites.Presentstudyrevealsthatthesolid-solutionstructureformedbysubstitutionbetweenCa2+andZn2+ionshassignificanteffectontheluminescencepropertiesofsinglephaseCa1-xZnxTiO3:0.002Pr3+phosphors.

简介：美国宇航局在加州帕萨迪纳的喷气推进实验室研究成功了一种制造YBa2Cu3O7-α高温超导电缆（封装在金属套管内）的新方法。据称,这种方法成本较低,过程易于控制,且对各种前体材料有很强的适应能力。该法分4个步骤:生产具有化学（配）比的前体（Precursor）粉;将前体粉包封在金属套管内;用轧制的方法使前体粉固结;在液态锂金属浴槽内进行处理,使之转变成超导组

简介：针对3~#皮带的产尘特点,分别在尾轮和首轮采用独立的防尘系统,加大收尘风量、定向气流排尘、活动刚性密闭、空气幕隔离、扁平罩收尘及低速文丘里除尘器除尘等综合防尘措施,防尘效果良好:3~#皮带工作场所粉尘浓度最高时才1.5mg/m~3,低于粉尘卫生标准2mg/m~3的允许值,尾气排放粉尘浓度最高时达47.0mg/m~3,在卫生标准100mg/m~3的允许范围之内.

简介：Ceriasphereswithdifferentsizesandsulfurizedproductswithcorrespondingmorphologywerepreparedbyhydrothermalandgas-solidreactionmethodat600–800°CunderCS2atmosphereforashorttime,respectively.Dimensionaleffectinpreparationofγ-Ce2S3wasfirstlyinvestigatedbymeansoftechniquessuchasscanningelectronmicroscopy(SEM),X-raydiffraction(XRD),thermalgravimetricanalysis(TGA)andspectrophotometer.Theresultsshowedthatwhenceriananoparticleswithsmallsizewereusedasprecursors,theγ-Ce2S3couldbepreparedatthelowertemperatureandthebadlysinteredproductswereobtained;whenceriananoparticleswithlargesizewereemployedasprecursors,pureγ-Ce2S3wasdifficultlyobtainedevenifthetemperaturewasupto800°Candtheproductstendedtokeeptheiroriginalsize.Theheat-resistancepropertyoftheγ-Ce2S3withlargesizewasbetterthanthesmallerone,andthepureγ-Ce2S3preparedfromprecursorwithsmallsizehadagoodpigmentaryperformance.

简介：针对长江钢铁1250m3高炉的开炉准备工作、开炉参数的选择、填充配料等方面的问题,对开炉及达产过程进行了分析总结.通过精细准备,合理控制操作参数以及调整后续过程,使得此次生产实践过程在工艺控制方面基本做到了平稳有序,实现了顺利开炉、快速达产的预定目标.

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简介：YLiF4:Er3+wassynthesizedbyhydrothermalmethod.ConcentrationofEr3+ischangedfrom0to5%.TheabsorptionofEr3+inallsamplesfrom200to1200nmwasmeasuredatroomtemperature.TheJ-OparameterscalculatedfromabsorptionspectrumareΩ2=1.05×10-20cm2,Ω4=1.25×10-20cm2andΩ6=1.35×10-20cm2.Infrared-to-visibleupconversionemissionofYLiF4:Er3+wasobservedwhenexcitedby980nm.TheresultsshowthattheEr3+contentislessthan1.5%,excite-stateabsorptionisthemainmechanismofupconversionemission.WhenEr3+contentislargerthan1.5%,bothoftheexcite-stateabsorptionandenergytransferleadtotheupconversionluminescence.TheupconversionintensitywasenhancedwiththeincreasingofEr3+concentration.Atroomtemperature,thelifetimeof2H11/2and4S3/2is205μswhilethatof4F9/2is188μsforsampleEr-2.Thetransitionratesandquantumefficiencywerealsocalculated.Thequantumefficienciesof4S3/2and4F9/2are27.9%and10.7%,respectively.

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简介：AseriesofLa2O3/MCnylonnanocompositeswerepreparedviainsitupolymerization.Theeffectsofcontentofnano-La2O3onthemechanicalpropertiesofnanocompositeswerestudied.Dispersionofnano-La2O3inMCnylonmatrixwasobservedwithSEM.ThecrystalstructureofnanocompositeswascharacterizedbymeansofXRD.SEManalysisshowsthatLa2O3nanoparticlesareuniformlydispersedinMCnylonmatrixandlittleclusteringexistswhenthecontentofnano-La2O3islowerthan1%,however,whenthecontentofnano-La2O3ismorethan1%,itbeginstocluster.XRDanalysisindicatsthatnano-La2O3doesnotchangethecrystalstructureofMCnylon.Mechanicalpropertiestestsshowthatthetensilestrength,elongationatbreak,impactstrength,flexuralstrength,andflexuralmodulusofnanocompositesfirstincreasethendecreaseasthecontentofnano-La2O3isincreased.Whenthecontentofnano-La2O3is0.5%,thetensilestrengthandelongationatbreakofnanocompositesreachmaximum,whichare17.9%and52.1%higherrespectivelythanthoseofMCnylon.Whenthecontentofnano-La2O3is1.0%,theimpactstrength,flexuralstrengthandflexuralmodulusofnanocompositesreachmaximum,whichare36.6%,12.7%and16.3%higherrespectivelythanthoseofMCnylon.

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简介：Inthispaper,varioustechniquesincludingBET,XRD,SEMandXPSwereusedtostudythesinteringofpureandLa2O3-dopedtitania.Theexperimentalresultsshowthatsinteringoftitaniaproceedsviavolumediffu-sion.Addingoflanthanumoxidedecreasestherateofsinteringandhindersthephasetransitionfromanatasetorutilecrystalbystrongsurfaceinteractionbetweenthemixedcrystals(La4Ti9O24,La0.66TiO2.99)andTiO2.

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简介：Sm3+dopedsodalimesilicateglassesco-dopedwithAs2O3werepreparedandcharacterisedbymeasuringtheirabsorptionspectrainUV-VIS/NIRregionsandluminescencespectrainthevisibleregion.Judd-Ofeltintensityparameters,Ωλ,wereevaluatedfromthemeasuredintensifiesofthevariousabsorptionbands.ΩλparametersoftheseglasseswerecomparedwiththeΩλparametersofotherreportedSm3+glassestostudythebondingenvironmentsurroundingtheSm3+inthepresentglasses.Presenceof[AsO4]3-tetrahedrainthesecondcoordinationspherearoundthecentralSm3+ionmadetheseglasseslesscovalentascomparedtootheroxideglassesbuttheratioΩ4/Ω6ofthe～1.83indicatedthemtobefairlystable.WiththehelpofΩλparametersandluminescencedataforvariousemissionlines,radiativepropertiesfordifferentemissionlineswerecalculated.Thevaluesofradiativepropertiesindicatedthat4G5/2→6H7/2and4G5/2→6H9/2transitionsresponsiblefororangeluminescencemightbeusedinthedevelopmentofmaterialsforLED'sandotheropticaldevicesinthevisibleregion.

简介：单斜晶、六角形的LaPO4:5mol.%Eu3+黄磷与仅仅在一样的合成温度由一个热水的方法调整答案的pH价值被综合。被不同准备影响的Eu3+-dopedLaPO4,的微观结构，形态学和光致发光调节，被X光检查衍射(XRD)描绘，扫描电子显微镜学(SEM)，Fourier变换红外线的光谱学(英尺红外)，拉曼光谱学和光光谱学分别地。然而，标本在强壮的酸答案显示出单斜晶的结构它在弱酸答案和强壮的碱答案变成了六角形的结构。单斜晶的LaPO4:Eu3+显示出最长的长度到直径比率，它被归因于优先的生长[-112]。单斜晶的标本与六角形的标本相比在红外线的系列，拉曼乐队位置和费用转移(CT)展出了细微红移动。而且，谷物尺寸的计算结果，格子参数，在在拉曼模式和排放积分紧张的半最大值的完整的宽度在对分析结果的好同意。单斜晶的标本显示出最大的绝对的光量收益(0.4)和第二一生2(0.52ms)，它与在CIE的红橘子的排放是一致的。5D07F1在六角形的标本占据了一个dominate位置，它显示在六角形的结构的更多的Eu3+被占据对称地点的倒置中心。

简介：分光镜并且在钠fluoroborate(SFB)的Nd3+离子的荧光性质眼镜通过光吸收，排放和腐烂大小被准备并且描绘。精力水平分析用免费离子的Hamiltonian模型被执行。试验性的振荡器力量被测量记录的吸收山峰包含的区域决定因为1.0mol.%Nd3+-做了眼镜。Judd-Ofelt参数(2,4,6)被用来评估象放射的转变那样的激光特征参数概率(AR)，放射的腐烂时间(R)，荧光分叉比率(R)和刺激排放为4F3/2的剖面图(e)亚稳的状态。为Nd3+离子的不同集中的荧光系列被在514.5nmAr+离子激光使样品激动记录。