简介：ThesinglecrystalgrowthofstoichiometrichostluminescentcrystalNa5Eu（WO4）4hasbeeninvestigated.UsingNa2WO4asaflux,theoptimumconditionstogrowapuresinglecrystalbyflux-slow-coolingmethodhavebeendetermined.Ahighopticalqualitysinglecrystalofdimention4.5mmhasbeengrown,whichisthelargestoneasweknowsofar.Themicro-hardnessofNa5Eu（WO4）4singlecrystalis3.46×103MPa.Itsrefractiveindexis1.81inwhitelightwavelengthregionandthespecificgravityis5.65g/cm3.Thefluorescentandexcitationspectrahavebeendeterminedandthereasonofthefluorescentquenchof5D2and5D1to7FjofEu3+canbeexplainedasmulti-phononnon-radiationtransition.

简介：ＳｐｅｃｔｒａｌＰａｒａｍｅｔｅｒＳｔｕｄｙｏｎＴｍ３＋ｉｎＮａ５Ｔｍ（ＷＯ４）４ＣｒｙｓｔａｌＹａｏＬｉａｎｚｅｎｇ（姚连增）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｒｉｎｇ，ＵｎｉｖｅｒｓｉｔｙｏｆＳｃｉｅｎｃ...

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.

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简介：Ca8Mg(SiO4)4Cl2:Eu2+phosphordopedwithSr2+cationforCa2+partially,wassynthesizedbysolid-statereactionathightemperatureunderreducingatmosphere,anditsluminescentpropertieswereinvestigated.TheexperimentalresultsindicatethattheemissionintensityofthephosphorincreasesafterbeingdopedwithafewamountofSr2+ion.Theemissionpeakofthephosphorblueshifttoabout464nmwhenthephosphorisdopedwithlargequantityofSr2+ions.TheexcitationspectrumindicatesthatthephosphorcanbewellexcitedbyUVandbluelightfrom300to460nm,andthephosphorwasfittedwellfortheexcitationbyUVorblue-LED.

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.

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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.

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简介：宜春钽铌矿机电车间铆接班采用下列工艺措施完成一个焊道熔火线开裂至整个母材的4m~3电铲铲斗修复任务。1.先用102不锈钢焊条打底,再用高锰钢焊条填满;2.在电弧切割的同时浇水冷却,以

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。

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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。

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简介：TheNaYF4:Yb,Ernanocrystalsweresynthesizedviathethermaldecompositionofmetaloleateprecursors.Thenanocrystalsinhexagonalstructurewerehighlyuniformandinsizeof25nm.Thebrightupconversionluminescencewasobservedundertheexcitationof980nmlaserandtheupconversionemissionspectrawereinvestigatedatdifferentpumppowers.Theemissionintensityratioofredlighttogreenlightlinearlyincreasedwithpumppowerincreasing.ThisresultindicatedthatthereexistedalargethresholdpowerofsaturationpumpforthefirstexcitationstateinNaYF4:Yb,Ernanocrystalscomparingtothatinbulkmaterial.

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.

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简介：YbAl3(BO3)4crystalofgoodopticalqualitywasgrownbythefluxmethod.ThestructureofYbAl3(BO3)4crystalwasdeterminedbysingle-crystalX-raydiffraction.TheexperimentshowsthatYbAl3(BO3)4belongstothedoubleborateswithatrigonalstructure.ThespacegroupisR32anditsunitcellconstantsweremeasuredtobea=0.92965nm,c=0.72129nm,V=0.53673nm3,Z=3.Thetransmittancespectraweremeasured.Thecut-offofYbAl3(BO3)4crystalis216nm,andtherearetwoabsorptionpeakslocatedat940and975nmfrom190nmto2600nm.ThethermalpropertiesofYbAl3(BO3)4crystalwerestudiedforthefirsttime.Theaveragethermalexpansioncoefficientsweredeterminedtobe2×10-6/℃,9.5×10-6/℃alonga-andc-direction.ThespecificheatofYbAl3(BO3)4crystalwasmeasuredtobe0.6695J·(g·℃)-1atroomtemperature.AllresultsindicatethattheYbAl3(BO3)4crystalisanexcellentstoichioimetriclasermaterial.

简介：Thesynthesisofprecursorofgreenphosphors,LaPO4:Ce,Tb,bymeansofco-precipitationwithcocurrentflowfeedwasstudied.Theeffectsofthereactiontemperature,thekindandconcentrationoftheacidinthebottomwater,andthechargingrateonthephysicalproperties,suchasparticlesize,wereinvestigated.Itisfoundthattheparticlesizeofthepowderiscontrollablebyadjustingacidityinbottomwaterandchargingrate.Thepowderwithdiametersizeof3to5μmwasobtained.ItsXRDandSEMwereanalyzed.XRDpatternsoftheas-preparedgreenphosphorpowdersdisplaythetypicalpeaksofCePO4.SEMshowsthatthemorphologyofpowdersisball-shaped.