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.

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：Er3+-Tm3+-Yb3+tri-dopedBaMoO4phosphorsweresynthesizedbyco-precipitationtechniqueandcharacterizedbyX-raydiffractionanalysis,absorptionstudyandfieldemissionscanningelectronmicroscopyanalysis.Upconversionaswellasdownconversionluminescencestudieswereperformedbyusingnearinfrared（980nm）andultraviolet（380nm）excitations.Energyleveldiagram,pumppowerdependenceandcolourcoordinatestudywereutilizedtodescribethemulticolorupconversionemissionproperties.Undersingle980nmdiodelaserexcitationthedualmodesensingbehaviourisrealizedviaStarksublevelsandthermallycoupledenergylevelsoftheTm3+andEr3+ionsinthepreparedtri-dopedphosphors.AcomparativefluorescenceintensityratioanalysisforintegratedemissionintensitiesarisingfromtheStarksublevels{1G4（a）and1G4（b）}andthermallycoupledenergylevels{2H11/2and4S3/2}oftheTm3+andEr3+ions,respectivelywascarriedoutinthepreparedtri-dopedBaMoO4phosphors.ThemaximumsensitivityforthermallycoupledenergylevelsoftheEr3+andStarksublevelsoftheTm3+ionwasreported.Thedevelopedphosphorscouldbeusefulinthedisplaydevicesandopticalthermometricapplications.

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