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921.
We study the interaction between tin(II) porphyrin (SnPor) with platinum and non-precious Group 8B metals (iron, cobalt and nickel) by density functional theory and discuss the electronic properties of the resulting products. We also model the interaction of the resulting compounds with water where applicable. Our studies indicate that, SnPor-Ni possesses electronic properties similar to SnPor-Pt, suggesting that it may possess similar photocatalytic properties for reduction reactions, such as converting water to hydrogen gas.  相似文献   
922.
We consider the effect of Coulomb interactions on the average density of states (DOS) of disordered low-dimensional metals for temperatures T and frequencies ω smaller than the inverse elastic life-time 1/τ. Using the fact that long-range Coulomb interactions in two dimensions (2d) generate ln2-singularities in the DOS ν(ω) but only ln-singularities in the conductivity σ(ω), we can re-sum the most singular contributions to the average DOS via a simple gauge-transformation. If σ(ω) > 0, then a metallic Coulomb gapν(ω) ∝ |ω|/e 4 appears in the DOS at T = 0 for frequencies below a certain crossover frequency Ω 2 which depends on the value of the DC conductivity σ(0). Here, - e is the charge of the electron. Naively adopting the same procedure to calculate the DOS in quasi 1d metals, we find ν(ω) ∝ (|ω|/Ω 1)1/2exp(- Ω 1/|ω|) at T = 0, where Ω 1 is some interaction-dependent frequency scale. However, we argue that in quasi 1d the above gauge-transformation method is on less firm grounds than in 2d. We also discuss the behavior of the DOS at finite temperatures and give numerical results for the expected tunneling conductance that can be compared with experiments. Received 28 August 2001 / Received in final form 28 January 2002 Published online 9 July 2002  相似文献   
923.
法律传统与法制现代化   总被引:1,自引:0,他引:1  
法律传统并非只是反映过去的法律文化精神,其中蕴含着许多可被现代法制吸收和借鉴的合理成分。法制现代化所面临的一个重要课题便是如何对待法律传统,如何协调好法制转型中的传统因素与现代因素,进而实现传统法律文化的创造性变革。本文试从法律传统的概念入手,对法制现代化承继法律传统的依据及承继进程中进行选择的必要性作了简要分析。  相似文献   
924.
In this paper, we study an existence theorem of systems of generalized quasivariational inclusions problem. By this result, we establish the existence theorems of solutions of systems of generalized equations, systems of generalized vector quasiequilibrium problem, collective variational fixed point, systems of generalized quasiloose saddle point, systems of minimax theorem, mathematical program with systems of variational inclusions constraints, mathematical program with systems of equilibrium constraints and systems of bilevel problem and semi-infinite problem with systems of equilibrium problem constraints. This research was supported by the National Science Council of the Republic of China.  相似文献   
925.
For any given positive integer n≥1,the Euler functionφ(n) is defined to be the number of positive integers not exceeding n,which is relatively prime to n.ω(n) is defined to be the number of different prime divisors of n.In order to know the solvability of the function ofφ(φ(φ(n)))=2~(ω(n)),properties of the number theoretical functionφ(φ(n)) is studied in the paper.  相似文献   
926.
一类拟线性大系统的稳定性   总被引:1,自引:0,他引:1  
本文应用大系统的分解方法和一个推广的不等式,研究了一类拟线性大系统的稳定性问题,所得结果简洁、易于验证,且推导过程不复杂,最后给出了应用实例。  相似文献   
927.
We continue to investigate strongly and weakly Lie remarkable equations, which we defined in a recent paper. We consider some relevant algebras of vector fields on ℝk (such as the isometric, affine, projective, or conformal algebras) and characterize strongly Lie remarkable equations admitted by the considered Lie algebras. __________ Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 151, No. 3, pp. 486–494, June, 2007.  相似文献   
928.
Approximation of signals from local averages   总被引:4,自引:0,他引:4  
This work is concerned with approximation of a signal from local averages. It improves a result of Butzer and Lei [P.L. Butzer, J. Lei, Approximation of signals using measured sampled values and error analysis, Commun. Appl. Anal. 4 (2000) 245–255].  相似文献   
929.
We consider goodness of fit tests for the Rayleigh distribution with grouped data. New Kolmogrov–Smirnov type tests are suggested and compared with the traditional chi-square and likelihood ratio tests. The results show that some of the suggested tests have a good power performance as compared with the traditional ones.  相似文献   
930.
赵德钧 《数学杂志》2006,26(3):335-342
本文研究一类多元Gauss-Weierstrass算子的线性组合加Jacobi型权逼近的性质,利用加权矩量不等式及加权K-泛函、光滑模等工具,建立了这类算子在Lp(1≤p≤∞)空间的正、逆定理和逼近阶的特征刻划.  相似文献   
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