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91.
用 X射线光电子能谱测定碳材料中碳 1s电子的结合能 ,是分析碳材料中碳原子有机结构的方法之一。本文利用量子化学从头计算程序对碳 1s电子的能量进行理论计算 ,结果表明 ,理论计算值与 ESCA仪器提供的标准值具有非常好的相关关系 ,用等式可表示为 :仪器推荐结合能 =(1.0 72± 0 .0 0 2 )×计算结合能。根据这一关系式 ,利用实验所得的元素组成 ,确定可能形成的化合物结构用量子化程序进行了理论计算 ,从而实现对未知结构碳材料样品 ESCA谱图的解析  相似文献   
92.
This paper outlines a simple method of counting the number of isomers of coordination compounds containing identical monodentate ligands and chelating ligands.  相似文献   
93.
Nucleic acid (NA) computation has been widely developed in the past years to solve kinds of logic and mathematic issues in both information technologies and biomedical analysis. However, the difficulty to integrate non-NA molecules limits its power as a universal platform for molecular computation. Here, we report a versatile prototype of hybridized computation integrated with both nucleic acids and non-NA molecules. Employing the conformationally controlled ligand converters, we demonstrate that non-NA molecules, including both small molecules and proteins, can be computed as nucleic acid strands to construct the circuitry with increased complexity and scalability, and can be even programmed to solve arithmetical calculations within the computational nucleic acid system. This study opens a new door for molecular computation in which all-NA circuits can be expanded with integration of various ligands, and meanwhile, ligands can be precisely programmed by the nuclei acid computation.  相似文献   
94.
Conditions are presented which are necessary for the existence of a regular fixed point of aC 1 map.Work supported in part by NSF Grant No. MCS 77-15509.Work supported in part by ONR Grant No. N0014-75-C-0495 and NSF Grant No. Eng. 76-81058.  相似文献   
95.
Computing free surface gravity flows involves basically two coupled problems, namely, the location of the free surface position and the determination of the internal flow field (for assumed values H0 and Q of the total head and discharge, respectively). Solution techniques are invariably based on iterative procedures, but those that iterate between the two coupled problems may become unstable. In this paper we present a computational method in which the coupling is kept throughout the process of iteration. This is achieved by converting the coupled problems (by means of the Kantorovich method) into the single problem of finding a set of streamlines, including that of the free surface. These streamlines are moved (iteratively) to satisfy the stationary conditions of the governing variational principle. The algorithm is very stable and converges rapidly. It is also easy to implement to solve various types of steady flows with a free surface under gravity.  相似文献   
96.
This paper is the continuation of a work initiated in [P. Sablonnière, An algorithm for the computation of Hermite–Padé approximations to the exponential function: divided differences and Hermite–Padé forms. Numer. Algorithms 33 (2003) 443–452] about the computation of Hermite–Padé forms (HPF) and associated Hermite–Padé approximants (HPA) to the exponential function. We present an alternative algorithm for their computation, based on the representation of HPF in terms of integral remainders with B-splines as Peano kernels. Using the good properties of discrete B-splines, this algorithm gives rise to a great variety of representations of HPF of higher orders in terms of HPF of lower orders, and in particular of classical Padé forms. We give some examples illustrating this algorithm, in particular, another way of constructing quadratic HPF already described by different authors. Finally, we briefly study a family of cubic HPF.  相似文献   
97.
In this paper we give a new definition of the chain recurrent set of a continuous map using finite spatial discretizations. This approach allows for an algorithmic construction of isolating blocks for the components of Morse decompositions which approximate the chain recurrent set arbitrarily closely as well as discrete approximations of Conley’s Lyapunov function. This is a natural framework in which to develop computational techniques for the analysis of qualitative dynamics including rigorous computer-assisted proofs.  相似文献   
98.
This paper proposes a homotopy continuation method for approximating all solutions to a system of polynomial equations in several complex variables. The method is based on piecewise linear approximation and complementarity theory. It utilizes a skilful artificial map and two copies of the triangulationJ 3 with continuous refinement of grid size to increase the computational efficiency and to avoid the necessity of determining the grid size a priori. Some computational results are also reported.  相似文献   
99.
针对所开发的新型径轴向混合填充式回热器进行了轴向导热特性的研究和分析.使用低热导率的非金属材料制作回热器管壁对回热器性能有积极影响.通过回热器轴向填料的轴向导热损失占填料总轴向导热损失90%以上.在通过回热器的三项轴向导热损失中,通过回热器填料轴向导热损失占主导地位,其与通过回热器管壁是两项可比拟的损失项,通过回热器中...  相似文献   
100.
The ‘Congruence Conjecture’ was developed by the second author in a previous paper [So3]. It provides a conjectural explicit reciprocity law for a certain element associated to an abelian extension of a totally real number field whose existence is predicted by earlier conjectures of Rubin and Stark. The first aim of the present paper is to design and apply techniques to investigate the Congruence Conjecture numerically. We then present complete verifications of the conjecture in 48 varied cases with real quadratic base fields.  相似文献   
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