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71.
Employing Dy2O3, Al2O3, and SiO2 as starting materials, several series of Dy2O3-Al2O3-SiO2 sealing glass were prepared. The relationship between their coefficients of thermal expansion and the contents of Dy2O3, Al2O3, and SiO2 were studied respectively. Experimental results showed that Dy2O3 and Al2O3 had a positive effect on the coefficient of thermal expansion of glass, whereas, SiO2 had a negative effect. The coefficient of thermal expansion of glass showed an apparent linear relation to the contents of these three raw materials, from which an estimation model was built, to calculate the coefficient of thermal expansion of sealing glass. Relative errors of the calculating results to testing results were no more than 2%, which suggested that the estimation model was reasonable. This study provides a good theory reference for the practical utilizing of this sealing material, through which a proper glass composition for good sealing could be easily found.  相似文献   
72.
采用高温固相法合成了层状LiNi0.25Co0.5Mn0.25O2正极材料。通过X射线衍射(XRD)、扫描电镜(SEM)、X射线光电子能谱(XPS)以及恒电流充放电测试,研究了LiNi0.25Co0.5Mn0.25O2材料的结构、形貌以及电化学性能。实验结果表明950℃7 h合成的样品具有最好的电化学性能,在0.1 C时2.5~4.3 V间,其首次充放电比容量分别为166.3 mAh/g和150 mAh/g,循环10周容量保持96%;XRD精修结果表明Li层中只有1.1%的位置被Ni所占据。  相似文献   
73.
李宏彦  朱志梁  杨凤丽  庄卫东 《硅酸盐学报》2012,40(4):577-578,579,580,581,582
采用体积电阻率法、红外光谱、X射线衍射研究了V2O5–P2O5–Sb2O3–Bi2O3体系玻璃的电性能、结构和析晶状况。结果表明:随着Sb2O3取代部分V2O5,玻璃的体积电阻率显著升高,电子分别以V4+和V5+为中心不停地进行电子跃迁的电子导电特征得到明显抑制,15%Sb2O3、20%Sb2O3玻璃的体积电阻率可以达到实用水平。当Sb2O3取代V2O5进入钒酸盐玻璃中,玻璃结构得到增强,析晶状况得到改善,削弱了玻璃的导电能力。  相似文献   
74.
Asthebackgroundlightofhighqualityliquidcrystaldisplay (LCD) ,coldcathodefluorescentlamp(CCFL)becametheresearchemphasisalongwiththedevelopmentofthemarketofLCD .AnimportantissueagainsttheapplicationofCCFListhebrightnessandlifetimeofthephosphors .CeMgAl11O19∶Tb3 (CMAT)isaveryimportantgreen emittingphosphorfortheim provementofbrightnessofCCFL .CeMgAl11O19∶Tb3 isakindofhexagonalpoly aluminatewiththestructureasshowninFig .1.Thecrystalstructureissimilartomagnetoplumbite (idealformula…  相似文献   
75.
High calcination temperature is an important factor in the preparation process of CeMgAl11O19∶Tb3 . To decrease the temperature, different fluxes(H3BO3, MgF2 and AlF3) were tested in order to compare their influence on the luminescence property and particle size distribution of CeMgAl11O19∶Tb3 . The result shows that when the content of MgF2 is 0.1 mol/mol, the intensity of luminescence can attain a maximum. Furthermore, MgF2 can improve the particle size quality of the phosphor. So MgF2 can take the place of the conventional flux H3BO3 to prepare high quality CeMgAl11O19∶Tb3 phosphor. In addition, the relation between phosphor property and content of AlF3 was also studied. The crystal structure of the phosphor was analyzed by XRD method. The phase composition analysis shows that the reason of decrease of the brightness of CeMgAl11O19∶Tb3 phosphor is the emergence of TbAlO3 and α-Al2O3 during the preparation process.  相似文献   
76.
稀土功能材料研究开发现状和发展趋势   总被引:7,自引:2,他引:7  
介绍了稀土磁性材料、稀土发光材料、稀土储氢材料、稀土催化材料等稀土功能材料的研究开发进展和产业发展现状,并对该领域目前面临的问题及发展趋势进行了探讨。  相似文献   
77.
Cubic and monoclinic Gd2O3:Eu3+ phosphors in the range of nano-scale and submicron-scale were prepared by a modified solution combustion method.Coexistence of cubic and monoclinic phases was found in the highest luminescent sample synthesized at 600 oC.In relation to commercial sample,the relative luminescence intensity was 49.8%.The shape of emission spectrum of the sample thus changed and the charge-transfer-state band of excitation spectrum slightly shift toward higher energies.With increasing the anneal...  相似文献   
78.
A precursor of the Y3Al5O12:Ce (YAG:Ce) phosphor was obtained by co-precipitation of the solution of high purity nitrates with ammonium bicarbonate solution. The precipitation process of the precursor was studied in this work. YAG:Ce yellow phosphors with fine morphology was synthesized by annealing the precursor at a reducing atmosphere. The crystal phase, microstructure of the phosphors and their photoluminescence were investigated. The results indicated that the pure phase of YAG:Ce could be obtained at ...  相似文献   
79.
用实验测定及理论计算相结合的方法构筑了SmI_2-AI(A:Na,K,Rb,Cs)体系的相图;并通过理论计算的方法预示了一套与优化相图自治的热力学数据.  相似文献   
80.
黄燕  叶红齐  庄卫东  胡运生 《功能材料》2007,38(7):1056-1059
用均相沉淀法制备得到草酸钇铕前驱体,在前驱体的焙烧中用熔盐Na2CO3、S、NaCl或它们的组合辅助其于1000~1300℃下焙烧2h制备Y2O3:Eu3 红色荧光粉.实验结果分析发现复合熔盐有利于Y2O3:Eu3 发光强度的提高,在1300℃焙烧时其主峰强度比不加熔盐量时的高36%,且高出商用Y2O3:Eu3 红粉的11%.熔盐配比的调节还可有效调控了Y2O3:Eu3 粉体的颗粒尺寸.  相似文献   
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