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101 个结果
  • 简介:ThesinglecrystalgrowthofstoichiometrichostluminescentcrystalNa5Eu(WO44hasbeeninvestigated.UsingNa2WO4asaflux,theoptimumconditionstogrowapuresinglecrystalbyflux-slow-coolingmethodhavebeendetermined.Ahighopticalqualitysinglecrystalofdimention4.5mmhasbeengrown,whichisthelargestoneasweknowsofar.Themicro-hardnessofNa5Eu(WO44singlecrystalis3.46×103MPa.Itsrefractiveindexis1.81inwhitelightwavelengthregionandthespecificgravityis5.65g/cm3.Thefluorescentandexcitationspectrahavebeendeterminedandthereasonofthefluorescentquenchof5D2and5D1to7FjofEu3+canbeexplainedasmulti-phononnon-radiationtransition.

  • 标签: Na5Eu(WO4)4 single crystal Host LUMINESCENCE Eu3+luminescence
  • 简介:四氧化三钴是一种重要的功能材料,主要用于生产锂离子电池正极材料钴酸锂。目前,制备四氧化三钴材料的主要方法有:溶液燃烧法,水热法,溶剂热法、溶胶一凝胶法、微波法等。本文研究用液沉淀法生成CoOOH,研究了试验过程中终点pH值,反应温度,不同碱氨配比对实验结果的影响。用此方法可以合成CoOOH,通过控制前驱体合成过程的各个影响因素,可以控制CoOOH的粒度、松比、振实等,得到比较理想的样品。后续通过煅烧CoOOH可以制备符合要求的钴酸锂。

  • 标签: 四氧化三钴 钴酸锂 液相沉淀 合成 COOOH
  • 简介:SpectralParameterStudyonTm3+inNa5Tm(WOCrystalYaoLianzeng(姚连增)(DepartmentofMaterialsScienceandEnginering,UniversityofScienc...

  • 标签: Rare earths NA 5Tm(WO 4) 4
  • 简介:ThephotoluminescencepropertiesofBiTaO4∶Pr3+andBiTaO4atroomtemperaturewerestudied,andtheinfraredtransmissionanddiffusionreflectionspectraofBiTaO4weremeasured.ThephotoluminescencespectrumofBiTaO4peaksatabout420,440and465nm.Therehasanobviousexcitationbandfrom330to370nm.ThephotoluminescencespectrumofBiTaO4∶Pr3+consistsofthecharacteristicemissionofPr3+,anditsmainpeakisat606nmfrom3P0→3H6transitionofPr3+.Itsexcitationspectrumconsistsofthewidebandwithmaximumat325nm,thewidebandintherangeof375~430nm,andthecharacteristicexcitationofPr3+.Thebandsat325nmand375~430nmmaybefromtheabsorptionofthechargetransfertransitionofthetantalategroupanddefectenergylevelsinitsforbiddenband,respectively.ThereisenergytransferfromhosttoPr3+.BecauseboththehostdensityandphotoluminescencepeakintensityofBiTaO4∶Pr3+aresuperiortoPbWO4,BiTaO4∶Pr3+maybeapotentialheavyscintillator.

  • 标签: BiTaO4 稀土 掺杂 发光材料 发光性能
  • 简介:Ca8Mg(SiO4)4Cl2:Eu2+phosphordopedwithSr2+cationforCa2+partially,wassynthesizedbysolid-statereactionathightemperatureunderreducingatmosphere,anditsluminescentpropertieswereinvestigated.TheexperimentalresultsindicatethattheemissionintensityofthephosphorincreasesafterbeingdopedwithafewamountofSr2+ion.Theemissionpeakofthephosphorblueshifttoabout464nmwhenthephosphorisdopedwithlargequantityofSr2+ions.TheexcitationspectrumindicatesthatthephosphorcanbewellexcitedbyUVandbluelightfrom300to460nm,andthephosphorwasfittedwellfortheexcitationbyUVorblue-LED.

  • 标签: CALCIUM MAGNESIUM chlorosilicate Eu2+ emission SPECTRUM
  • 简介:介绍了气法白炭黑的制备原理与生产工艺,通过解决生产过程中的技术难点及创新点,提高了白炭黑的产品质量,降低了生产成本,促进了资源的循环利用。

  • 标签: 气相法白炭黑 四氯化硅 工艺
  • 简介:英美资源最新的产量报告显示,旗下位于巴西戈亚斯州的两家镍铁厂BarroAlto和Codemin2015年第四季度产量为1.05万金属吨,较前一季度环比增长54%,同比增长57%,主要是受益于BarroAlto两座电炉重建提前完成,并已迭产,数据显示第四季度该镍铁厂产量季比增幅达72%至8100吨,同比增长80%;Codemin季比产量增幅14%,同比增长9%,主要是矿石品位增加,该冶炼厂矿源来自BarroAlto。

  • 标签: 金属量 镍铁 资源 同比增长 数据显示 矿石品位
  • 简介:据外电2月21日消息,英美资源(AngloAmerican执行总裁MarkCutifani周二表示,如果对其智利ElSoldado铜矿的重新设计无法获得许可,将会停止该矿生产。该集团希望在三到四周内获得监管部门的批准,不过如果无法获得一份令人满意的许可,MarkCutifani,“我们将不会继续运营该矿。”

  • 标签: EL 智利 资源 生产 铜矿 MARK
  • 简介:Trivalentdysprosium(Dy3+)activatednanocrystallineyttriumvanadate(YVO4)phosphorwassynthesizedviaco-precipitationmethod.ThepreparedsampleswerecharacterizedbyX-raydiffraction(XRD),Fouriertransforminfraredspectroscopy(FTIR),scanningelectronmicroscopy(SEM),opticalabsorptionandphotoluminescence(PL)techniques.TheXRDpatternsrevealthetetragonalcrystallinephase.SEMimagesrevealthatDydopedYVO4nanocrystalsareagglomerated.EDAXconfirmstheformationofYVO4:Dy.FTIRspectrumshowstwostrongabsorptionbandsat459and761cm-1.Opticalabsorptionspectrumshowedthesurfacedefectsintheas-preparedsamples.ThePLemissionspectrumshowstwocharacteristicemissionbandsat485and575nm.Thestrongyellowemissionpeakat575nmisassignedto4F9/2→6H13/2hypersensitivetransitionofDy3+ions,StudyofCIEchromaticitydiagramindicatesthesuitabilityofthephosphorforthedevelopmentofyellow-greenLEDs.

  • 标签:
  • 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.

  • 标签: 萃取机制 离子液体 萃取剂 系统 双功能 Cyanex923
  • 简介:结合马钢4号高炉TRT系统的工艺概况、系统组成等方面介绍了其平面布置,并从选址、防火间距、煤气净化、设施间距、检修空间等方面介绍在进行TRT系统平面布置时需要注意的问题。

  • 标签: 高炉 TRT 平面布置
  • 简介:采用元胞自动机模型建立了05Cr17Ni4Cu4Nb不锈钢固溶过程的二维模型,模拟了固溶过程中的晶粒形核生长以及化合物的扩散溶解,模拟结果动态地再现了固溶过程的微观组织特征。通过该模型分析了固溶温度和固溶时间对固溶处理后微观组织的影响。

  • 标签: 05Cr17Ni4Cu4Nb 元胞自动机 固溶
  • 简介:TheNaYF4:Yb,Ernanocrystalsweresynthesizedviathethermaldecompositionofmetaloleateprecursors.Thenanocrystalsinhexagonalstructurewerehighlyuniformandinsizeof25nm.Thebrightupconversionluminescencewasobservedundertheexcitationof980nmlaserandtheupconversionemissionspectrawereinvestigatedatdifferentpumppowers.Theemissionintensityratioofredlighttogreenlightlinearlyincreasedwithpumppowerincreasing.ThisresultindicatedthatthereexistedalargethresholdpowerofsaturationpumpforthefirstexcitationstateinNaYF4:Yb,Ernanocrystalscomparingtothatinbulkmaterial.

  • 标签: 上转换发光 纳米晶体 一致性 泵浦功率