KKM定理的一个推广

本文引入了Z-空间概念,定义了一类新的映射：Z-KKM映射,推广了著名的FKKM定理及其它各种形式的KKM定理.     

中性红催化动力学光度法测定痕量硒(Ⅳ)

利用硫酸介质中,痕量硒(Ⅳ)强烈催化氯酸钾氧化中性红褪色反应,建立一种快速测定痕量硒(Ⅳ)的催化动力学光度法.结果表明:最大吸收波长为530nm,检出限为2.4×10-9g/mL,摩尔吸光系数为2-71×104L·mol-1·cm-1,硒含量在0.1-0.4/μg/25mL范围内呈线性关系,线性回归方程为AA=0.0045 0.4271CSe(Ⅳ)(μg//25mL),相关系数r=0.9996,直接用于黑木耳、黄花菜和香菇中硒(Ⅳ)的测定,结果令人满意.     

Deformation of super Virasoro algebra in noncommutative quantum superspace

We present a twisted commutator deformation for N = 1,2 super Virasoro algebras based on GL_q(1,1) covariant noncommutative superspace.     

A Generalized F-expansion Method and Its Application in High-Dimensional Nonlinear Evolution Equation

A generalized F-expansion method is introduced and applied to (3 1)-dimensional Kadomstev-Petviashvili(KP) equation. As a result, some new Jacobi elliptic function solutions of the equation are found, from which the trigonometric function solutions and the solitary wave solutions can be obtained. The method can also be extended to other types of nonlinear evolution equations in mathematical physics.     

Uniformly 3-connected graphs

Let $k$ be a positive integer. A graph is said to be uniformly $k$-connected if between any pair of vertices the maximum number of independent paths is exactly $k$. Dawes showed that all minimally 3-connected graphs can be constructed from $K_4$ such that every graph in each intermediate step is also minimally 3-connected. In this paper, we generalize Dawes' result to uniformly 3-connected graphs. We give a constructive characterization of the class of uniformly 3-connected graphs which differs from the characterization provided by Göring et al., where their characterization requires the set of all 3-connected and 3-regular graphs as a starting set, the new characterization requires only the graph $K_4$. Eventually, we obtain a tight bound on the number of edges in uniformly 3-connected graphs.     

E1 radiation decay of isobaric analog resonances

Within the framework of the shell-optical model a quantitative interpretation for partial E1 radiation widths of isobaric analog resonances (IAR) has been proposed for near-magic nuclei over a wide atomic mass range. Spin-flip transitions as well as non-spin-flip ones are considered. A dependence of polarization effects on the spin-isospin part of the quasiparticle effective interaction is cleared up for transitions of different type. The results of calculations are compared with the experimental data.     

纳米结构自组装和分子自组装体系

系统地总结并评述了纳主结构和自组装体系和分子自组装体系的最新进展,介绍了纳米结构自组装和分子自组装的基本概念,总结了几类自组和分子自组装体系的合成方法,例举了这类自组装体系的新特性及与下一代纳米结构器件之间的联系。     

原子荧光光谱法测定环境水及土壤样品中的汞形态含量

采用氢化发生-冷原子荧光光谱法,测定了厦门市集美周边地区的几种水和土壤样品中汞的不同形态含量。在仪器优化条件下直接进样测定水中微量无机汞的含量,再用溴酸钾-溴化钾消解水样并测定其总汞含量,由总汞与无机汞含量之差计算出有机汞含量;采用微波消解体系测定土壤样品中的总汞含量,同时用连续化学浸提法提取测定包括可交换态汞、盐酸溶汞、元素汞、腐殖酸结合态汞、有机质结合态汞和硫化汞的不同汞形态含量,并最终测定残态汞含量。实验结果表明,实验室排放水中汞含量高于Ⅰ类污水综合排放标准(GB 8978—1996),说明实验室排放水是严重的汞环境污染源之一。而公路边土壤、近海沉积物和菜园土壤的汞形态含量均低于相应的国家标准,但由于人为污染造成菜园土壤汞的不断积累应引起高度重视。实验同时对水和土壤样品的测量检出限及方法回收率进行试验,结果表明在优化的实验条件下水和土壤汞的检出限分别为0.000 8 μg·L-1和0.072 3 μg·kg-1,3个水平的加标平均回收率分别为93.7%和93.8%,方法准确、可靠。     

Influence of phonon confinement on the optically detected magneto-phonon resonance line-width in quantum wells

We investigate the influence of phonon confinement on the optically detected magneto-phonon resonance (ODMPR) effect and ODMPR line-width in quantum wells. The ODMPR conditions as functions of the well's width and the photon energy are also obtained. The shifts of ODMPR peaks caused by the confined phonon are discussed. The numerical result for the GaAs/AlAs quantum well shows that in the two cases of confined and bulk phonons, the line-width (LW) decreases with increasing well's width and increases with increasing temperature. Furthermore, in the small range of the well's width, the influence of phonon confinement plays an important role and cannot be neglected in reaching the ODMPR line-width.