ASYMPTOTIC APPROXIMATION METHOD AND ITS CONVERGENCE ON SEMI-INFINITE PROGRAMMING

The aim of this article is to discuss an asymptotic approximation model and its convergence for the minimax semi-infinite programming problem. An asymptotic surrogate constraints method for the minimax semi-infinite programming problem is presented by making use of two general discrete approximation methods. Simultaneously, the consistence and the epi-convergence of the asymptotic approximation problem are discussed.     

半正二阶三点边值问题的解和正解

考察了非线性二阶三点边值问题的n个解和正解的存在性,其中允许非线性项有一个负的下界并且n是一个任意的自然数．主要结论表明该问题可以具有n个解或者正解,只要非线性项在某些有界集上的“高度”是适当的．     

AN IMPROVED SEARCH-EXTENTION METHOD FOR SOLVING SEMILINEAR PDES

This article will combine the finite element method, the interpolated coefftcient finite element method, the eigenfunction expansion method, and the search-extension method to obtain the multiple solutions for semilinear elliptic equations. This strategy not only grently reduces the expensive computation, but also is successfully implemented to obtain multiple solutions for a class of semilinear elliptic boundary value problems with non-odd nonlinearity on some convex or nonconvex domains. Numerical solutions illustrated by their graphics for visualization will show the efficiency of the approach.     

多值渐近φ-半压缩型映象三步迭代集合序列的强收敛性

利用新的分析方法,在任意实Banach空间中证明了具(随机性)误差的三步迭代集合序列强收敛于多值渐近Φ-半压缩型映象的不动点集．得到一些新的结论．     

半线性方程组边界层解的存在性

本文利用隐函数定理讨论了含小参数的半线性椭圆方程组边界层解的存在性．     

PAA/PVA SIPN高吸水性树脂的制备及性能研究

采用水溶液法合成了聚丙烯酸-聚乙烯醇(PAA-PVA)半互传网络型高吸水性树脂,其工艺条件的优化结果为:丙烯酸(AA)与PVA质量比为10∶0.5,AA中和度为80%,加入AA单体质量0.14%的引发剂和0.025%的交联剂,产物吸水率为530g/g,吸盐水率达63g/g。并采用红外光谱法表征了半互穿网络结构的形成。     

超微半扁球电极的稳态电流理论及其验证

本文用苯醌在Ｍｃｌｌｖａｉｎｅ缓冲溶液（ｐＨ＝７．０）中的电化学可逆还原反应体系验证了超微半扁球电极上的稳态电流方程式，理论与实验结果相符，超微半扁球汞电极用电镀法制备。     

~(13)C-NMR化学位移与聚合物的构象——Ⅱ.1,2-聚丁二烯仲碳(—CH_2—)的~(13)C-NMR谱研究

在1,2-聚丁二烯链分子中,导致仲碳(—CH_2—)谱峰分裂的原因是存在着两种gauche排列。在这样一个复杂体系中,由于主链仲碳与叔碳的gauche排列占有重要的位置,因此主链叔碳对化学位移的贡献对于仲碳谱有着决定性的影响。相比之下,乙烯基的贡献要小得多。两种贡献分别是γ_1=—6.37——6.41ppm与γ_2=0.0——1.56ppm。在不计入侧基的影响或同时考虑乙烯基的贡献这两种情况下,均方误差MSE分别是0.166×10~(-2)和0.364×10~(-2)ppm~2。本文同时讨论了模型链的种类、链长以及温度对键概率的影响。并指出有个别反常的情况发生。文中还对间同1,2-聚丁二烯的链结构进行了分析。     

溶胶-凝胶法制备桥式聚倍半硅氧烷/SiO2光学防潮膜

采用溶胶-凝胶法, 以首次合成的具有桥式结构的间苯二亚甲基二脲基丙基三乙氧基硅烷(m-XDUPTEOS)和正硅酸乙酯(TEOS)为前驱体, 共同水解缩聚制备了不同摩尔配比的桥式聚倍半硅氧烷/SiO₂杂化溶胶, 并旋涂制膜. 通过UV-Vis, AFM和TGA对薄膜的光学性能、表面形貌和热稳定性进行了分析. 结果表明, 该薄膜平整均匀、具有良好的光学透明性、热稳定性和防潮性能.     

Structural Features of a Polysaccharide from Centella asiatica

Centella asiatica has been used as remedy for sodation, stabilization and against lepra, anabrosis1 in the oriental countries. The low-molecular-weight constituents in Centella asiatica have been investigated1. However, no polysaccharides have been reported. 1BI was the first polysaccharide isolated from C. asiatica, which had immunostimulating activity in vitro. In present study, we report the structural features of 1BI. Experimental Extraction, isolation and purification Dried C.…