“Г—环中存在强诣零根”的命题是错误的

本文针对Ｃｏｐｐａｇｅ与Ｌｕｈ的论文中定理５．４，用一个实例有力地指出该定理是错误的，这个实例指出，尽管任何一个结合环都有一个诣零根，但推广到Г－环中，并不是任何一个Г－环都有强诣零根，因而Г环决不是结合环的平行推广．     

一种新型的二元光学器件——多位相光束分束器的制作

本文报道了用于多光束分束器的反射式16位相值二元光学器件的制作。该二元光学器件把一束光束分成5×5光束阵列。测量的衍射效率为76.16%,接近理论设计值79.68%。该二元光学器件的有效孔径为10mm×10mm。     

在可交换四元数空间中的双曲方程的特征边值问题

讨论了一阶和二阶双曲复方程的特征边值问题.对其中两种线性方程,分别在不同的情况下获得通解和可解条件.而对于拟线性的二阶双曲复方程,证明了解的存在性和唯一性.     

QUATERNION GENERALIZED SINGULAR VALUE DECOMPOSITION AND ITS APPLICATIONS

This paper derives a theorem of generalized singular value decomposition of quaternion matrices （QGSVD）,studies the solution of general quaternion matrix equation AXB -CYD= E,and obtains quaternionic Roth＇s theorem. This paper also suggests sufficient and necessary conditions for the existence and uniqueness of solutions and explicit forms of the solutions of the equation.     

我国中小企业选择可靠信用担保机构的模式识别方法

首先运用模糊评价方法结合中小企业选择信用担保机构现状，构建了当前我国信用担保机构5种标准信用等级的模糊向量，然后在此基础上采用“择近原则”得到m个等待选择的信用机构所处于的最为“贴近”的标准信用等级，从而为我国中小企业选择可靠信用担保机构提供了一种新的量化方法。     

红外光谱对碱土金属二元羧酸盐结构的研究

研究了三十种二元羧酸金属盐的红外光谱，讨论了金属离子和二元酸的种类对二元酸盐配位结构的影响。发现Mg盐、Ba盐，Sr盐为螯合配位，Ca盐，Zn盐中同时存在螯合配位和桥式配位，二元酸的种类对羧酸盐配位结构没有影响。对羧酸盐在常温和熔融后的栩位方式和结构上的差异的研究结果表明，Mg盐，Ca盐与Sr盐，Ba盐在熔融后的结构变化不同。     

极紫外望远镜各通道夹角的测量

极紫外望远镜是由四个单通道的望远镜捆绑在一起,以便同时对太阳的相同部分观测,由于受地面装调以及发射过程中的影响,无法保证四个通道光轴严格平行,必然带来观测位置上的误差。只要测出各通道之间的光轴夹角,便可在像面上采取适当的处理方法,以便减小这种误差,但这一夹角的测量精度必须控制在0.1″内。为达到如此高的精度,采用了太阳局部边缘探测的方法,很好地解决了这一问题。     

THE COUPLING OF NATURAL BOUNDARY ELEMENT AND FINITE ELEMENT METHOD FOR 2D HYPERBOLIC EQUATIONS

In this paper, we investigate the coupling of natural boundary element and finite element methods of exterior initial boundary value problems for hyperbolic equations. The governing equation is first discretized in time, leading to a time-step scheme, where an exterior elliptic problem has to be solved in each time step. Second, a circular artificial boundary FR consisting of a circle of radius R is introduced, the original problem in an unbounded domain is transformed into the nonlocal boundary value problem in abounded subdomain. And the natural integral equation and the Poisson integral formula are obtained in the infinite domainΩ2 outside circle of radius R. The coupled variational formulation is given. Only the function itself, not its normal derivative at artificial boundary ΓR, appears in the variational equation, so that the unknown numbers are reducedand the boundary element stiffness matrix has a few different elements. Such a coupled method is superior to the one based on direct boundary element method. This paper discusses finite element discretization for variational problem and its corresponding numerical technique, and the convergence for the numerical solutions. Finally, the numerical example is presented to illustrate feasibility and efficiency of this method.     

Silane photoabsorption spectra mear the Si 2p thresholds：the geometry of Si 2p excited SiH4

Based on the multiple-scattering self-consistent-field method, we have studied the photoabsorption spectra near the Si 2p thresholds of silane. According to our calculations, the clear assignments of the inner-shell photoabsorption spectra are provided. In comparison with the high-resolution experimental spectra, the geometric structure of the Si 2p-excited SiH_{4}^{**} is recommended to be of a C_{2v} symmetry. More specifically, the Si 2p-excited SiH_{4}^{**} have two bond lengths of 2.50 a.u. and another two bond lengths of 2.77 a.u., and the corresponding two bond angles are 104.0° and 112.5° respectively.     

Fe-V-N稀合金中空位复合体特性的研究(Ⅱ)

本文利用离散变分法,集团模型和三维数值弛豫技术,研究了Fe-V-N稀合金中V-N-空位复合体的几何构型,正电子湮没特性和电子结构。根据正电子湮没寿命实验的结果和总能量极小原理,确定了V和N在V-N-空位复合体中的最佳占据位置。分析了V-N-空位复合体的成键特性和电荷转移情况。 关键词：