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991.
992.
The one-dimensional W-doped VO2 (M) solid solutions with a various doped content were successfully synthesized under hydrothermal condition and subsequent calcination for the first time, and physical-chemical and phase transformation character were explored, subsequently. DSC analyses displayed that the phase-transition temperature of VO2 (M) solid solution could be linearly tuned with the doped content. Promisingly, the one-dimensional W-doped VO2 (M) had a good thermochromic property. 相似文献
993.
Min-Jie Li Chun-Li Hu Yong Zhou Jiang-Gao Mao 《Journal of solid state chemistry》2009,182(5):1245-1251
Three new ternary potassium(I) zinc(II) or cadmium(II) tellurides, namely, K2Cd2Te3, K6CdTe4 and K2ZnTe2, were synthesized by solid-state reactions of the mixture of pure elements of K, Cd (or Zn) and Te in Nb tubes at high temperature. K2Cd2Te3 belongs to a new structure type and its structure contains a novel two-dimensional [Cd2Te3]2− layers perpendicular to the b-axis. K(5) cation is located at the center of five member rings of the 2D [Cd2Te3]2− layer, whereas other K+ cations occupy the interlayer space. K6CdTe4 with a K6HgS4 type structure features a “zero-dimensional” structure composed of isolated CdTe4 tetrahedra separated by the K+ ions. K2ZnTe2 in the K2ZnO2 structural type displays 1D [ZnTe2]2− anionic chains of edge sharing [ZnTe4] tetrahedra separated by the potassium(I) ions. K2Cd2Te3, K6CdTe4 and K2ZnTe2 revealed a band gap of 1.93, 2.51 and 3.0 eV, respectively. 相似文献
994.
In this article, the authors mainly discuss the law of large number under Kalikow's condition for multi-dimensional random walks in random environment with holding times. The authors give an expression to the escape speed of random walks in terms of the Lyapounov exponents, which have been precisely used in the context of large deviation. 相似文献
995.
996.
We prove the superconvergence of Morley element and the incomplete biquadratic nonconforming element for the plate bending
problem. Under uniform rectangular meshes, we obtain a superconvergence property at the symmetric points of the elements and
a global superconvergent result by a proper postprocessing method.
The research is supported by the Special Funds For Major State Basic Research Project (No. 2005CB321701). 相似文献
997.
Based on new deformation theorems concerning strongly indefinite functionals, we give some new min-max theorems which are useful in looking for critical points of functionals which are strongly indefinite and satisfy Cerami condition instead of Palais-Smale condition. As one application of abstract results, we study existence of multiple periodic solutions for a class of non-autonomous first order Hamiltonian system
998.
研究了一类时滞离散神经网络指数稳定及鲁棒稳定问题.结合线性矩阵不等式技术,构造了一个新的广义李亚普诺夫函数,得到了新的指数稳定条件.数值算例表明与以往文献中的结果相比,新准则具有较弱的保守性. 相似文献
999.
The existence of radial solutions of Δu + λg(|x|)f(u) = 0 in annuli with Dirichlet(Dirichlet/Neumann) boundary conditions is investigated.It is proved that the problems have at least two positive radial solutions on any annulus if f is superlinear at 0 and sublinear at ∞. 相似文献
1000.