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  • 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: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: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相的扩散溶解,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:针对电厂除灰渣系统渣浆泵流量过大,水耗、电耗过高的状况,对渣浆泵叶轮进行了切割改造,从而取得了显著的节电、节水效果.

  • 标签: 渣浆泵 流量 扬程 叶轮 切割 节电
  • 简介:在流程工业生产中,移动物料计量信息的传输普遍采用电台和无线模块。接收电台周围环境严重影响计量信息的传输效果,尤其是钢结构厂房、电磁干扰区内,数据传输过程中的丢包率、误码率相当严重。本文提出一种多节点分布式传输方法,根据各个生产作业区环境条件设置相应的wIFI节点数,实现对作业区的无线信号覆盖。网络覆盖区内无线模块、PDA终端(PDA)、终端查询设备通过节点工作频段和阵列天线自适应调节,实现数据传输最佳化。铜熔炼生产现场测试表明,可以有效消除周围环境的电磁干扰,数据丢包率低于0.1%。

  • 标签: 分布式传输 WIFI节点 自适应调节 阵列天线 丢包率
  • 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
  • 简介:Resinsofcomplexesmadefromagarose-Ce4+(RCA-Ce)andchitosan-Ce4+(RCC-Ce)wereprepared.Hydrolysisratesofmethamidophos,omethoateandchlorpyrifostreatedbyRCA-Cewere32.39%,27.12%and46.62%,respectively,thoseofchlorpyrifosandmethamidophosinmungbeansproutjuice38.28%and35.45%,andthatofchlorpyrifosinteaextract59.76%.HydrolysisratesofproteininteaextracttreatedbyRCA-Ceincreasedby86.46%.RCC-Cecouldbeemployedintheapplejuiceproduction.Thecontentsofmethamidophosandparathion-methylinthejuicetreatedbyRCC-Cedecreased58.76%and71.92%.Furthermore,RCC-Cewasusedtoclarificationforbeerbythewaysofacolumn.RCC-Cecouldhydrolyzesensitiveproteinandincreasecontentsoffreeaminoacidinthebeer.Therefore,thebeertreatedbyRCC-CecouldstayoxidationandagingprocedureduetosomemetalionsbeingabsorbedbyRCC-Ce.

  • 标签: RESINS POLYSACCHARIDES CERIUM hydrolyze protein ORGANOPHOSPHOROUS