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951.
952.
The enzymatic kinetic resolution of α-hydroxysilanes where the silicon bears a variety of substituents has been explored. Reactions were performed on various α-hydroxysilanes with several commercially available enzymes, solvents, acetylation reagents, and temperatures. The resulting optically active α-hydroxysilanes and their corresponding acetates were obtained in varying yields and ees. 相似文献
953.
A numerical method is presented for form-finding of cable-strut structures. The topology and the types of members are the only information that is required in this form-finding process. Dummy members are used to transform the cable-strut structure with supports into self-stressed system without supports. The requirement on rank deficiencies of the force density and equilibrium matrices for the purpose of obtaining a non-degenerate d-dimensional self-stressed structure has been explicitly discussed. The spectral decomposition of the force density matrix and the singular value decomposition of the equilibrium matrix are performed iteratively to find the feasible sets of nodal coordinates and force densities which satisfy the minimum required rank deficiencies of the force density and equilibrium matrices, respectively. Based on numerical examples it is found that the proposed method is very efficient, robust and versatile in searching self-equilibrium configurations of cable-strut structures. 相似文献
954.
Nguyen Buong 《数学学报(英文版)》2010,26(3):587-594
The aim of the paper is to propose an iterative regularization method of proximal point type for finding a common solution for a finite family of inverse-strongly monotone equations in Hilbert spaces. 相似文献
955.
We introduce two new methods for solving a backward heat conduction problem. For these two methods, we give a stability analysis with new error estimates. Meanwhile, we investigate the roles of the regularization parameters in these two methods. Numerical results show that our algorithm is effective. 相似文献
956.
Le Thi Phuong Ngoc Nguyen Anh Triet Nguyen Thanh Long 《Nonlinear Analysis: Theory, Methods & Applications》2010,72(3-4):1865-1885
The paper is devoted to the study of a linear wave equation with a nonlinear boundary condition of viscoelastic type. The existence of a weak solution is proved by using the Faedo–Galerkin method. The uniqueness, regularity and asymptotic expansion of the solution are also discussed. 相似文献
957.
The Suzuki-Miyaura reaction of 2,3-dibromobenzofuran with two equivalents of boronic acids gave 2,3-diarylbenzofurans. The reaction with one equivalent of arylboronic acids resulted in site-selective formation of 2-aryl-3-bromobenzofurans. 2,3-Diarylbenzofurans containing two different aryl groups were prepared from 2,3-dibromobenzofuran in a one-pot protocol by sequential addition of two different boronic acids. 相似文献
958.
959.
Nguyen Ba An 《Physics letters. A》2009,373(20):1701-1707
Three novel probabilistic yet conclusive schemes are proposed to teleport a general two-mode coherent-state superposition via attenuated quantum channels with ideal and/or threshold detectors. The calculated total success probability is highest (lowest) when only ideal (threshold) detectors are used. 相似文献
960.