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991.
By the interpolation inequality and a priori estimates in the weighted space, the existence of global solutions for generalized
Ginzburg-Landau equation coupled with BBM equation in an unbounded domain is considered, and the existence of the maximal
attractor is obtained.
This research is supported by the National Natural Science Foundation of China (No.19861004). 相似文献
992.
明镇寰 《浙江大学学报(理学版)》2001,28(1):67-71
本文对生命中最复杂的动态分子机器——核糖体的结构研究进行了综述 ,介绍了最新对核糖体大、小亚基分别为 5 和 5.5 分辨率的结构研究 ,尤其强调了 50 S大亚基的因子结合中心和 30 S小亚基的 16 Sr RNA中心域结构的研究进展 相似文献
993.
Esteghlalian Ali R. Srivastava Vinit Gilkes Neil R. Kilburn Douglas G. Warren R. Antony J. Saddler John N. 《Applied biochemistry and biotechnology》2001,91(1-9):575-592
This article provides an overview of various theories proposed during the past five decades to describe the enzymatic hydrolysis
of cellulose highlighting the major shifts that these theories have undergone. It also describes the effect of the cellulose-binding
domain (CBD) of an exoglucanase/xylanase from bacterium Cellulomonas fimi on the enzymatic hydrolysis of Avicel. Pretreatment of Avicel with CBDCex at 4 and 37°C as well as simultaneous addition of CBDCex to the hydrolytic enzyme (Celluclast, Novo, Nordisk) reduced the initial rate of hydrolysis owing to irreversible binding
of CBD proteins to the substrate's binding sites. Nonetheless, near complete hydrolysis was achieved even in the presence
of CBDCex. Protease treatment of both pure and CBDCex-treated Avicel reduced the substrates' hydrolyzability, perhapsowing to proteolysis of the hydrolyzing enzyme (Celluclast)
by the residual Proteinase K remaining in the substrate. Better protocols for comptete removal of CBD proteins from the substrate
need to be developed to investigate the effect of CBD adsorption on cellulose digestibility. 相似文献
994.
We consider additive two‐level preconditioners, with a local and a global component, for the Schur complement system arising in non‐overlapping domain decomposition methods. We propose two new parallelizable local preconditioners. The first one is a computationally cheap but numerically relevant alternative to the classical block Jacobi preconditioner. The second one exploits all the information from the local Schur complement matrices and demonstrates an attractive numerical behaviour on heterogeneous and anisotropic problems. We also propose two implementations based on approximate Schur complement matrices that are cheaper alternatives to construct the given preconditioners but that preserve their good numerical behaviour. Through extensive computational experiments we study the numerical scalability and the robustness of the proposed preconditioners and compare their numerical performance with well‐known robust preconditioners such as BPS and the balancing Neumann–Neumann method. Finally, we describe a parallel implementation on distributed memory computers of some of the proposed techniques and report parallel performances. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
995.
Jorge Ivn García-Sucerquia Romn Castaeda Francisco F. Medina Giorgio Matteucci 《Optics Communications》2001,200(1-6):15-22
Theoretical considerations, simulations and experiments have been carried out to distinguish between Fresnel and the Fraunhofer diffraction regarding the formation of interference patterns by a conventional Young's double-pinhole arrangement with variable separation, which is illuminated by a coherent plane wave. We show that the optical path difference introduced by this setup fits the Fresnel's phase difference between the pinholes. Consequently, it is possible to determine the number of Fresnel zones subtended by a circle centered on one of the pinholes and with radius equals to the pinhole separation. Then, we propose a criterion for distinguishing between Fresnel and Fraunhofer diffraction based on this number of Fresnel zones, which is applicable for diffracting apertures with any shape. 相似文献
996.
997.
998.
Mathematical Notes - 相似文献
999.
1.引言 近年来,一类新的区域分解法-非匹配网格区域分解法,日益引起人们的广泛兴趣.这类区域分解法的特点是:相邻子区域在公共边(或面)上的结点可以不重合,从而可方便地处理匹配网格区域分解法难以处理的问题:变动网格问题(例如石油勘探中的地层错动问题)和最优网格设计问题(即根据解的性质和实际问题的要求在不同子区域上采用不同的单元类型,不同的网格尺寸和不同阶的逼近多项式). 在这类区域分解的算法设计中面临着两个困难:界面上非协调性的处理(与通常的协调元不同)和界面上积分的有效计算.现有算法中较引人注目的… 相似文献
1000.
管冰辛 《数学的实践与认识》2001,31(4):478-482
本文讨论了第一类超 Cartan域 YI上的双全纯不变量 JY1(w,z;w,z)以及当 (w,z)趋于边界 YI时JYI的极限 相似文献