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111.
Bi12TiO20纳米粉体的制备及其光吸收特性研究 总被引:3,自引:0,他引:3
以钛酸四丁酯和硝酸铋为原料 ,利用化学溶液分解法制备了Bi12 TiO2 0 纳米多晶粉体 .采用XRD和TEM对其结构和形貌进行了表征 .结合热重 差热 (TG DTA)分析 ,探讨了Bi12 TiO2 0 晶相的形成机理 .通过UV Vis漫反射谱的测定 ,研究了Bi12 TiO2 0 纳米晶粉体的光吸收特性 .结果显示 ,从组成为化学计量比的前驱液中可以很容易制得纯Bi12 TiO2 0 纳米晶粉体 ,该Bi12 TiO2 0 纳米晶粉体呈现了在很宽的波长范围内 (5 6 0~ 385nm )对光的吸收的特性 . 相似文献
112.
完全Rees矩阵半群的分解及性质 总被引:1,自引:0,他引:1
用等价关系Q^~出了完全Rees矩阵半群的一种分解.而且得到了它的每个Q^~一类的表示. 相似文献
113.
Baoqing Zeng Ning Liu Zhonghai Yang 《International Journal of Infrared and Millimeter Waves》2004,25(11):1621-1631
Vacuum microelectronic triode performance, based upon a unit cell with a nanotube field emitter, gate, and anode, was evaluated via computer simulation. Electron emission was calculated from the modified Fowler-Nordheim equation. The dependence of emitted current, upon geometrical factors, e.g., nanotube radius, nanotube height, and gate's hole radius, is shown. The device design parameters of trans-conductance, and cutoff frequency have been calculated, which show that this structure can be used as a microwave and millimeter wave amplifier. Electron current flux is shown for time-dependent 1–Thz sinusoidal variation frequency input. 相似文献
114.
Qinghai He 《Journal of Mathematical Analysis and Applications》2007,333(2):1070-1078
In this paper, variational conclusions of set-valued bifunctions on convex subsets of Banach spaces are investigated and several new results are obtained. The results are applied to the fixed point theory and variational inequalities. We obtain two fixed point theorems and existence theorems of solutions of variational inequalities. 相似文献
115.
116.
Zhen‐Feng Chen Hong‐Li Zhou Hong Liang Yan Li Ren‐Gen Xiong Xiao‐Zeng You 《应用有机金属化学》2003,17(11):883-884
The centrosymmetric binuclear structure of [Pb2(H‐Norf)2(ONO2)4]shows the geometry around each lead(II) atom to be distorted trigonal bipyramidal with Pb–O distances ranging from 2.357(3) to 2.769(4) Å. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
117.
Testing for additivity with B-splines 总被引:1,自引:0,他引:1
Regression splines are often used for fitting nonparametric functions, and they work especially well for additivity models. In this paper, we consider two simple tests of additivity: an adaptation of Tukey's one degree of freedom test and a nonparametric version of Rao's score test. While the Tukey-type test can detect most forms of the local non-additivity at the parametric rate of O(n-1/2), the score test is consistent for all alternative at a nonparametric rate. The asymptotic distribution of these test statistics is derived under both the null and local alternative hypotheses. A simulation study is conducted to compare their finite-sample performances with some existing kernel-based tests. The score test is found to have a good overall performance. 相似文献
118.
Yiran He 《Journal of Global Optimization》2007,39(3):419-426
The existence of global error bound for convex inclusion problems is discussed in this paper, including pointwise global error
bound and uniform global error bound. The existence of uniform global error bound has been carefully studied in Burke and
Tseng (SIAM J. Optim. 6(2), 265–282, 1996) which unifies and extends many existing results. Our results on the uniform global
error bound (see Theorem 3.2) generalize Theorem 9 in Burke and Tseng (1996) by weakening the constraint qualification and
by widening the varying range of the parameter. As an application, the existence of global error bound for convex multifunctions
is also discussed. 相似文献
119.
Fabrication of bamboo-shaped GaN nanorods 总被引:1,自引:0,他引:1
H. Li J.Y. Li M. He X.L. Chen Z. Zhang 《Applied Physics A: Materials Science & Processing》2002,74(4):561-562
Bamboo-shaped GaN nanorods were formed through a simple sublimation method. They were characterized by means of X-ray powder
diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and selected-area
electron diffraction (SAED). The TEM image showed that the nanorods were bamboo-like. XRD, HRTEM and SAED patterns indicated
that the nanorods were single-crystal wurtzite GaN.
Received: 8 January 2001 / Accepted: 28 April 2001 / Published online: 20 December 2001 相似文献
120.
曾韧英 《应用数学与计算数学学报》1997,11(1):27-32
本文讨论定义在Banach空间上的,既具有等式约束又具有不等式约束的,非光滑(F,P)不变凸多目标规划的Wolfe对偶性,Mond-Weir型对偶性可类似讨论之。 相似文献