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991.
Xing-Ling Xu Zong-Xun Tang Zhi-Zheng Guo Yun-Sheng Chen Ni-Cheng Shi Zhe-Sheng Ma Yu-Zhen Han 《中国化学》1995,13(1):54-62
Based in the phase equilibrium study of the system Sm(C1O4)3-4-monochloroacetytantipyrine (C13H13ClN2O2)-H2O at 30°C, we have synthesized the title complex [Sm(C13H13Cl-N2O2)3(H2O)4](ClO4)3-4H2O. The single crystal structure analysis on RASA-IIS Rigaku diffractometer shows that the coordination number of the metal ion is nine and the geometry of the complex is tricapped trigonal prism. Two of the three molecules of organic ligand act as bidentate chelated through both carbonyl oxygens to the metal ion, but the other one as a monodentate coordinated only through the ring carbonyl oxygen, the side chain carbonyl is far away from the central ion. The crystal is monoclinic, space group P21, α = 18.013(4), b = 14.709(3), c = 10.536(3) Å, β=94.69(2)°, V=2782(1) Å3, Z=2. 相似文献
992.
Optical absorption of Er3+ ion in Er(NO3)3·5H2O, NH4NO3, Mg(NO3)2·6H2O, KNO3 and NaNO3 complexes has been studied. The second derivative spectra of these Er3+ complexes exhibited splittings in the4
I
9/2,4
F
9/2,4
F
7/2,4
F
5/2 and2
H
9/2 levels. These splittings have been tentatively explained as due to a cubic crystalline field. The partial derivatives for
Er3+ ion have been calculated in terms of Racah (E
k
) parameters. The results of a least squares fit of the energy levels and oscillator strengths of the bands are reported in
terms of interaction parameters and Judd-Ofelt parameters. Radiative transition probabilities for various fluorescence levels
are theoretically estimated. The lifetime of the4
G
11/2 level is found to be lowest in all nitrate complexes. 相似文献
993.
Nikolaos S Papageorgiou 《Journal of multivariate analysis》1985,17(2):207-227
This second part of the work on Banach space valued multifunctions begins with a detailed study of set valued martingales, which have their values in a Banach space. Several new convergence theorems are established for different modes of convergence. The profile of a multifunction in connection with set valued martingales is also studied. The notion of weak convergence of multifunctions is introduced and used to obtain additional convergence theorems for set valued martingales. In the last two sections of the paper set valued measures dealt with and an integral with respect to a set valued measure is introduced. 相似文献
994.
We consider the equilibrium problem for a plate with a crack. The equilibrium of a plate is described by the biharmonic equation. Stress free boundary conditions are given on the crack faces. We introduce a perturbation of the domain in order to obtain an invariant Cherepanov–Rice-type integral which gives the energy release rate upon the quasistatic growth of a crack. We obtain a formula for the derivative of the energy functional with respect to the perturbation parameter which is useful in forecasting the development of a crack (for example, in study of local stability of a crack). The derivative of the energy functional is representable as an invariant integral along a sufficiently smooth closed contour. We construct some invariant integrals for the particular perturbations of a domain: translation of the whole cut and local translation along the cut. 相似文献
995.
基于两点边值问题 ,本文在改进的单元正交估计和连续性优化的基础上 ,研究了一种n次有限元单元块导数重构 ,该方法所获得的重构导数在单元块内部有n- 1个强超收敛点 . 相似文献
996.
997.
导数空间另一类D’Alembert原理及任意阶非完整系统的新型Maggi方程 总被引:1,自引:0,他引:1
作为笔者在文献[1,2,3]中提出的“导数空间”和导数空间中“相当动能”的概念及“将非完整系统变为形式上的完整系统处理”思想的具体应用,本文导出了又一类新型的万有D′Alembert原理及适用于任意阶非完整系统的新型的Maggi方程,并给出了应用此方程的算例。 相似文献
998.
Guochun Wen 《中国科学A辑(英文版)》1998,41(4):346-356
Oblique derivative boundary value problems for the linear mixed (elliptic-hyperbolic) equation of the second order, i.e. the
generalized Lavrent’ev-Bitsadze equation with weak conditions are discussed. The representation of solutions for the above
boundary value problem is given, the uniqueness and existence of solutions of the above problem are proved, and a priori estimates
of the solutions of the above problem are obtained.
Project supported by the National Natural Science Foundation of China. 相似文献
999.
We derive and analyze Monte Carlo estimators of price sensitivities (“Greeks”) for contingent claims priced in a diffusion model. There have traditionally been two categories of methods for estimating sensitivities: methods that differentiate paths and methods that differentiate densities. A more recent line of work derives estimators through Malliavin calculus. The purpose of this article is to investigate connections between Malliavin estimators and the more traditional and elementary pathwise method and likelihood ratio method. Malliavin estimators have been derived directly for diffusion processes, but implementation typically requires simulation of a discrete-time approximation. This raises the question of whether one should discretize first and then differentiate, or differentiate first and then discretize. We show that in several important cases the first route leads to the same estimators as are found through Malliavin calculus, but using only elementary techniques. Time-averaging of multiple estimators emerges as a key feature in achieving convergence to the continuous-time limit. 相似文献
1000.
小波在微分方程数值解上的应用 总被引:2,自引:0,他引:2
求解微分方程常见的方法包括有限差分、有限元等.近年来,小波理论迅速发展,用小波方法数值解求解微分方程已越来越引起人们的注意.本文引入小波的基本理论,通过将函数及其各阶导数在小波基上的展开,求解微分方程的数值解. 相似文献