刘文鹏
,
张庆礼
,
杨华军
,
周鹏宇
,
孙敦陆
,
高进云
,
谷长江
,
罗建乔
,
王迪
,
殷绍唐
量子电子学报
doi:10.3969/j.issn.1007-5461.2011.02.018
采用固相反应法制备了Bi3+、Eu3+、Tb3+掺杂的Lu3TaO7.测量了样品的X射线衍射谱、激发和发射光谱及荧光衰减曲线.三种离子掺杂的Lu3TaO7均呈现出强的荧光发射,其中Bi3+具有峰位在431 nm处的一强发射宽带,衰减寿命为16.8μs,Eu3+、Tb3+则表现出稀土离子的特征锐发射峰,衰减寿命分别为1.26 ms和1.20 ms.因此,它们均是具有潜在应用前景的重闪烁体材料.
关键词:
材料
,
闪烁体
,
Lu3TaO7
,
发光
季振国
,
周荣福
,
毛启楠
,
霍丽娟
,
曹虹
无机材料学报
doi:10.3724/SP.J.1077.2009.09217
利用反应磁控溅射法制备了半导体锡锑氧化物薄膜 (TAO). 根据霍尔效应测试结果,当Sn/Sb 原子比处于0.22~0.33范围内时,TAO薄膜是p型导电的,在此范围之外,TAO薄膜是n型导电的. 光学带隙测量结果表明,不同Sn/Sb比的TAO薄膜的禁带宽度基本相同(～3.9eV).构造了一个全透明的PN结,其中n区为Sn/Sb原子比为0.5的TAO薄膜, p区为Sn/Sb原子比为0.33的TAO薄膜.n区TAO的电极用铟锡氧化物(ITO),p区TAO的电极用Cu薄膜.实验结果表明,由于两种导电类型的TAO薄膜具有相同的禁带宽度,上述透明PN结构具有典型的准同质PN结的整流特性.
关键词:
透明半导体薄膜
,
锡锑氧化物
,
PN结
Journal of Applied Physics
Based on the developed multiple-scattering theory [C.-W. Nan and F. S. Jin, Phys. Rev. B 48, 8578 (1993)], an effective-medium theory (EMT) is proposed to treat coupled electromechanical behavior in composite media. The explicit relations for determining effective behavior of piezoelectric composites are derived. To illustrate the technique, numerical results of piezoelectric ceramic/epoxy composites for various particle shapes are presented over the whole range of concentrations. The EMT estimates are shown to be in good agreement with available experimental results. Porous piezoelectric ceramics are also discussed. The EMT predicts a similar critical behavior for heterogeneous piezoelectric materials to recent experiments.
关键词:
electromechanical properties;ceramics
Physics of Life Reviews
Commentaries by Philip W.T. Pong, Nongyue He, S.D. Liang, Tao Song, Yuri Gaididei and Sergey Volkov and Alexander Y. Grosberg on my review article (Pang, 2011 [1]) are answered. The validity of Davydov's mechanism of bio-energy transport, the completeness of theory, outstanding problems, the normalization and validity of wave function of the system in Pang' model as well as other related problems are elucidated in detail. (C) 2011 Elsevier B.V. All rights reserved.
关键词:
biological temperature;3 channels;soliton;model
成艳
,
蔡伟
,
李洪涛
,
郑玉峰
,
赵连城
功能材料
采用多弧离子镀的方法在Ti-50.6%(原子分数)Ni形状记忆合金表面沉积了钽镀层.通过X射线光电子能谱(XPS)剖面分析发现TiNi合金表面钽镀层厚度均匀,并且在镀层与基体之间形成一薄层过渡层.将镀钽TiNi合金曝露于空气中后,通过XPS的全谱和高分辨谱图对其表面的成分和价态分析发现,镀钽层表面由于钽在空气中自然氧化形成了一层很薄的钽的氧化膜,最表面为高价钽的氧化物(Ta2O5),次表面为低价钽氧化物的混合物TaO2、TaO和TaOx(x＜1).
关键词:
TiNi形状记忆合金
,
多弧离子镀
,
钽
,
镀层
李江鸿
,
张红波
,
熊翔
,
肖鹏
,
黄伯云
稀有金属材料与工程
报道了一种在C/C复合材料基体上制各抗烧蚀TaC涂层的新方法.采用红外光谱、XRD及SEM表征了生成TaC涂层的Ta源:TaO2F·rH2O·TaF5.采用SEM观察了不同温度下转变生成的TaC涂层的形貌.在1200℃高温热处理,TaC涂层形貌为细颗粒状,在1800℃高温热处理后,TaC涂层为柱状晶.TaC的生成机制为:TaO2F·rH2O·TaF5高温分解凝聚生成的Ta2O5沉积在C/C复合材料基体表面,碳原子在Ta2O5中扩散反应生成TaC,TaC涂层形貌可由生成Ta2O5的凝聚成核理论解释.
关键词:
TaC涂层
,
制备
,
生成机制
Acta Materialia
In a first report [Jin ZH.. Gumbsch P, Ma E, Albe K, Lu K, Hahn H, et al. Scripta Mater 2006;54:1163], interactions between screw dislocation and coherent twin boundary (CTB) were studied via molecular dynamics simulations for three face-centered cubic (fcc) metals, Cu, Ni and Al. To complement those preliminary results, purely stress-driven interactions between 60 degrees non-screw lattice dislocation and CTB are considered in this paper. Depending on the material and the applied strain, slip has been observed to interact with the boundary in different ways. If a 60 degrees dislocation is forced by an external stress into a CTB, it dissociates into different partial dislocations gliding into the twin as well as along the twin boundary. A sessile dislocation lock may be generated at the CTB if the transited slip is incomplete. The details of the interaction are controlled by the material-dependent energy barriers for the formation of Shockley partial dislocations from the site where the lattice dislocation impinges upon the boundary. (c) 2007 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
关键词:
dislocation;slip;twinning;twin grain boundary;molecular dynamics;molecular-dynamics simulation;grain-boundaries;nanocrystalline;materials;cross-slip;rate sensitivity;deformation;copper;strength;aluminum;fcc
