Compared with micro - sized y2o3 : eu and gd2o3 : eu phosphors prepared by a conventional method , nanosized y2o3 : eu and gd2o3 : eu synthesized by the present work , gives a clear blue shift in the emission spectrum , and a clear red shift in the excitation spectrum 同时，发现了纳米晶一些新奇的发光性质，即：发射光谱蓝移现象，激发光谱红移中电荷迁移带( ctb )明显红移，猝灭浓度提高等。
Y2o3 : eu nanotubes were synthesized by a surfactant assembly mechanism . tem image confirms the formation of the tubular structures . under the excitation of ultraviolet light , the nanotubes show luminescence properties different from that of y2o3 : eu nanocrystallites 低温下的激光选择激发光谱表明，处于纳米管壁内部的发光中心具有较为确定的格位对称性，其发射光谱具有清晰的光谱结构。
Weight up y2o3 and ai2o3 with the mole proportion of 3 / 5 . after sufficient grinding , we got the round pieces of f 20mm and thickness 5mm with 30mpa pressure . then sinter the pieces in the hydrogen atmosphere at 1700 ? for 5 hours 按照摩尔比为3 ： 5称取纯度为99 . 99的y _ 2o _ 3和al _ 2o _ 3 ，将配好的原料充分研磨混合，然后用30mpa的压力压制成f20mm 、厚度为5mm的薄片，在高温钨钼炉中通流动氢气，在1700下烧结5小时。
The observation on the microstructures of matrices and cathodes indicate that eusco3 exists in sintered matrices and cathodes of e3 , while sc2o3 and y2o3 form a complete solid solution in matrices of y3 . the influence of microstucture to the emission properties of cathodes have been discussed 对烧结基体和阴极的微观结构进行了分析,结果表明e3基体和阴极中生成了eusco3 , y3基体中sc2o3和y2o3完全形成了的固溶体,讨论了微观结构对阴极性能的影响。
The results show : la2o3 , ceo2 , nd2o3 is applicable for the additives of mh electrode because of the good comprehensive performance of the negative especially during the high rate discharge phase ; y2o3 is not fit as an additive for mh electrode ; the ceo2 content in negative has great effects on the performance during the high rate discharge phase and 2 % ( mass percentage ) is the best one , furthermore , the improvement of purity of ceo2 is beneficial to the comprehensive performance ; the mixture of coo and ceo2 as a additive is more suitable for mh electrode during the high rate discharge phase whose properties are better than that of addition of coo and ceo2 respectively 研究表明， mh电极中添加la _ 2o _ 3 、 ceo _ 2 、 nd _ 2o _ 3显著提高了电极电化学综合性能，尤其是大电流放电性能，适宜作大电流放电下电池负极的添加剂； y _ 2o _ 3不适宜作负极添加剂； ceo _ 2添加量对大电流放电性能影响较大， ceo _ 2的适宜添加量2wt ；提高ceo _ 2纯度能改善mh电极电化学综合性能。 mh电极中添加coo 、 ceo _ 2复合添加剂后电极综合性能比单独添加coo和ceo _ 2更优良，适宜作大电流放电下电池负极的添加剂。
In this article , molybdenum wire multi - doped with la2o3 and k , al , si , molybdenum wire doped with k , al , si and molybdenum wire doped with la2o3 or y2o3 are analyzed by dsc , hot - draw , sem , optical microscope , micro - hardness , x - ray and tem . it is found that multi - doped molybdenum wire is better at elevating the recrystallization temperature and improving the micro - structure and mechanic properties after recrystallization than molybdenum wire doped with k , al , si 本文通过差热分析、热模拟、扫描电镜、金相显微镜、显微硬度、 x射线衍射和透射电镜等实验手段对复合掺杂k 、 al 、 si和稀土氧化物的钼丝、单掺杂k 、 al 、 si的钼丝以及单掺杂稀土氧化物的钼丝的再结晶温度、高温下的综合力学性能和组织形貌进行了综合对比分析。
The increase of radiative transition rate with decreasing particle size was attributed to the lower symmetry surrounding the eu3 + ions , while the increase of nonradiative transition rate to the extra nonradiative transition channels caused by surface defects . ( 3 ) under excitation of 488 nm , temperature - dependence of emission intensity of the 5d4 - 7fj transition in nanocrystalline y2o3 : tb was studied . in nanocrystalline , there appeared two maximal intensities ( 3 )研究了488nm激光激发下不同颗粒尺寸的y _ 2o _ 3 ： tb纳米晶荧光发射强度随温度的变化规律，发现y _ 2o _ 3 ： tb纳米晶荧光发射强度在280k与590k存在两个极大值，而体材料只在280k有一个极大值。
Moreover , the falling rate of its microhardness is minished . molybdenum wire doped with la2o3 is better at enhancing mechanic properties and microstructure than molybdenum wire doped with y2o3 . furthermore , la2o3 particles are easier to diffuse to the grains boundary than y2o3 particles under high temperature 此外，本实验还发现，掺杂la2o3比掺杂y2o3更有利于提高钼丝高温下的力学性能，改善钼的烧结态形貌，降低其孔隙率，减小其晶粒尺寸,且la2o3颗粒比y2o3的颗粒更容易在高温下扩散到晶界上去。
Detailed emission and excitation spectral characteristics have been analyzed and discussed . in addition , spectral red - shift has been found in both charge transfer bands in nanocrystalline y2o3 : eu 3 + compared to the bulk material . the number ratio of s6 sites to c2 sites is also smaller in nanocrystalline y2o3 : eu3 + than that in the bulk one 与体材料相比，两种格位的电荷迁移带在纳米材料中都发生红移；相对于c _ 2格位的电荷迁移带， s _ 6格位的电荷迁移带强度在纳米材料中比在体材料中明显降低。
Nanoparticles and nanocluster materials are a new class of advanced materials exhibiting unique chemical and physical properties compared to those of their bulk materials . y2o3 : eu and gd2o3 : eu are efficient red - emission phosphor . recent studies show that they have significant promise in the field of luminescent materials 纳米材料由于其介观效应而表现出不同于常规体材料的独特物理化学性质，因而对纳米材料的合成和性质研究已经成为材料科学、物理学以及化学学科的前沿。
