Nanocrystalline yttrium vanadate doped with europium ions powders were synthesized via sol-gel method based on decomposition of metal-polymer complex. X-ray diffraction analysis showed that samples had pure tetragonal...Nanocrystalline yttrium vanadate doped with europium ions powders were synthesized via sol-gel method based on decomposition of metal-polymer complex. X-ray diffraction analysis showed that samples had pure tetragonal phase without any impurities. Scanning electron microscopy and static light scattering technique were used to study morphology and size of prepared nanoparticles. Average diameter of the nanoparticles was about 40 nm. The changes in structural and luminescence properties were observed as a function of the first and second calcination temperature. The optimal conditions for synthesis of nanoparticles were determined as Т1=500℃, t1=1 h; Т2=950 ℃, t2=1.5 h. The effect of different media surrounding the nanoparticles on their luminescence properties and lifetime was investigated and discussed in terms of effective refractive index. It was found that the observed lifetime of YVO4:Eu^3+ 5 at.% nanophosphor was decreased from 0.64 ms in air(nmed=1) to 0.45 ms in chalcogenide glass As39S61(nmed=2.39).展开更多
纸为温度地论述围住的体积热来源和相应功能分析的表情。这里考虑的力量密度分布正常、指数、寓言。来源由于熔化和团结为象焊接的弧,激光横梁,电子横梁,等等,在焊接水池的传送对流以及潜伏的热一样的真实的热来源建模。热来源模型...纸为温度地论述围住的体积热来源和相应功能分析的表情。这里考虑的力量密度分布正常、指数、寓言。来源由于熔化和团结为象焊接的弧,激光横梁,电子横梁,等等,在焊接水池的传送对流以及潜伏的热一样的真实的热来源建模。热来源模型的参数是未知的 priori 并且不得不被解决一个反的热传导问题评估。为在靶子焊接的精明的 3D 温度地的功能分析的技术被开发。建议技术使更加为数据输入和答案减少全部的时间可能。它与激光横梁焊接钢盘子的一个例子被表明。展开更多
文摘Nanocrystalline yttrium vanadate doped with europium ions powders were synthesized via sol-gel method based on decomposition of metal-polymer complex. X-ray diffraction analysis showed that samples had pure tetragonal phase without any impurities. Scanning electron microscopy and static light scattering technique were used to study morphology and size of prepared nanoparticles. Average diameter of the nanoparticles was about 40 nm. The changes in structural and luminescence properties were observed as a function of the first and second calcination temperature. The optimal conditions for synthesis of nanoparticles were determined as Т1=500℃, t1=1 h; Т2=950 ℃, t2=1.5 h. The effect of different media surrounding the nanoparticles on their luminescence properties and lifetime was investigated and discussed in terms of effective refractive index. It was found that the observed lifetime of YVO4:Eu^3+ 5 at.% nanophosphor was decreased from 0.64 ms in air(nmed=1) to 0.45 ms in chalcogenide glass As39S61(nmed=2.39).
文摘纸为温度地论述围住的体积热来源和相应功能分析的表情。这里考虑的力量密度分布正常、指数、寓言。来源由于熔化和团结为象焊接的弧,激光横梁,电子横梁,等等,在焊接水池的传送对流以及潜伏的热一样的真实的热来源建模。热来源模型的参数是未知的 priori 并且不得不被解决一个反的热传导问题评估。为在靶子焊接的精明的 3D 温度地的功能分析的技术被开发。建议技术使更加为数据输入和答案减少全部的时间可能。它与激光横梁焊接钢盘子的一个例子被表明。