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Manyboratesareexcellenthostsforrareearthlu minescence ,forexample ,nowbestredphosphorinplasmadisplaypanel (PDP )is (Y1-xGdx)BO3∶Eu[1] .Boratephosphorsdopedwithrareearthionshavebeenrichlystudiedinthepastfewdecades[2 ,3] .RecentlyWuYichengetal .[4 ] synthesizedanewbo rateLa2 CaB10 O19,whichispotentialnonlinearopticalmaterials.InthisworkweselectedLa2 CaB10 O19ashostofluminescencematerialsbecauseitprobablyisabetterhostforrareearthluminescence .Duetotherequirementofplasmadisplaypenal(PDP)… 相似文献
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Luminescence and defect properties of novel phosphor β-Zn3(PO4)2:Zr4 were systematically investigated. Corresponding to its lowest optical absorption transition at 240 nm, phosphor emits a bluish-green light at 485 nm, which yields the Stokes shift about 20000 cm-1. The unusual optical properties of Zr4 ion are ascribed to its uncommon coordination environment. In addition it shows intensive bluish-green long lasting phosphorescence(LLP) due to the existence of electron trap, which is generated by aliovalent substitution of Zr4 ion for the cation site in the matrix as shown in thermoluminescence(TL) spectrum. 相似文献
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根据 Tb在 K IQ_4—KOH—K_2S_2O_8体系中的氧化反应,建立了混和稀土中 Tb 的分光光度分析方法.Tb被氧化为 Tb~(4+),其颜色由无色转变为红棕色,最大吸收峰在420nm.Ce~(3+)加入 KIO_4—KOH 溶液后,立即被完全氧化为 Ce~(4+),Ce~(4+)在420nm 也有吸收,其干扰可以在本底中排除,其它三价稀土离子在此体系中不能发生氧化反应,故无干扰.在 Tb 的分析浓度范围为5×10~(-5)~5×10~(-4)M 时,符合 Beer 定律,Tb 在混合稀土中含量分析的最低限为1%。此方法可用于萃取稀土过程中 Tb 的分析和监控,方法简便快速。 相似文献
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Luminescence Properties of Sm^3+ doped Bi2ZnB2O7 总被引:4,自引:0,他引:4
The phosphors of (Bi1- x Smx ) 2ZnB2O7 ( x = 0. 01, 0. 03, 0. 05, 0. 07, and 0. 09) were synthesized by conventional solid state reaction. The purity of all samples was checked by X-ray powder diffraction (XRD). XRD analysis shows that all these compounds are of a single phase of Bi2ZnB2O7, indicating that the Bi^3+ in Bi2ZnB2O7 can be partly replaced by the Sm^3+ without the change of crystal structure. The excitation and emission spectra at room temperature show the typical 4f-4f transitions of Sm^3+ . The dominant excitation line is around 404 nm due to ^6H5/2→^4K11/2 and the emission spectrum consists of a series of lines at 563, 599, 646, and 704 nm due to ^4G5/2→^6H5/2, ^6H7/2, ^6H9/2, and ^6H11/2, respectively. The optimal concentration of Sm^3+ in Bi2ZnB2O7 is about 3mol% (relative to lmol Bi^3+ ) and the critical distance Rc was calculated as 2.1 nm. The temperature dependence of the emission intensity of Bi1.94Sm0.06ZnB2O7 was examined in the temperature range between 100 and 450 K. The quenching temperature where the intensity has dropped to half of the initial intensity is 280 K. The lifetime for Sm^3+ in Bi1.94Sm0.06ZnB2O7 is fitted as a value of 0.29 and 1.03 ms. 相似文献
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在纲要的重点领域及其优先主题的第(31):基础原材料内,明确提出了要重点研究开发满足国民经济基础产业发展需求的稀土材料。 相似文献
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