结构种群动力系统

在这篇文章中,我们通过综述近２０年来对生理结构种群动力系统的研究概况,介绍了算子半群,分岔等非线性分析的数学理论,特别是无穷维动力系统理论在种群生态学研究中的应用。我们希望由此引起对如何应用现代数学理论研究种群生态学的更多的思考。     

周期系数的高维Riccati方程的周期解

本文研究了周期系数的高维Riccati方程X’＝X·A（t）·X＋B（t）·X＋C（t）,其中X∈R(n×1)A（t）∈R(1×n),B（t）∈R(n×n),C（t）E∈R(n×1);A（t）,B（t）,C（t）均是以2π为周期的实连续矩阵或向量函数,建立了该方程存在广义周期解的一个充要条件和存在周期解的两个充分条件,推广了周期系数的Riccati方程存在周期解的一些结论．     

二维周期系数线性微分方程的特征指数

给出利用系数直接判定二维周期系数线性微分方程特征指数符号的若干结论．     

一类广义矢量偏微分方程的并矢格林函数解及其应用

利用傅里叶变换、留数定理,求解了一类广义矢量偏微分方程的并夫格林函数,研究了无界空间的积分解,并应用于具体物理实例．     

On Compatibility Conditions for the Left Cauchy–Green Deformation Field in Three Dimensions

A fairly general sufficient condition for compatibility of the left Cauchy–Green deformation field in three dimensions has been derived. A related necessary condition is also indicated. The kinematical problem is phrased as a suitable problem in Riemannian geometry, whence the method of solution emerges naturally. The main result of the paper is general in scope and provides conditions for the existence of solutions to certain types of overdetermined systems of first-order, quasilinear partial differential equations with algebraic constraints. This revised version was published online in August 2006 with corrections to the Cover Date.     

Volcano relationships in metal cluster catalysis: An infrared spectroscopic monitor of site character

Active osmium cluster catalysts (derived from Os₃(CO)₁₂, H₂Os₃(CO)₁₀, H₄Os₄(CO)₁₂, Os₆(CO)₁₈ and H₂Os₁₀C(CO)₂₄ supported on silica, alumina, titania, and ceria) contain, in their infrared spectra, a band in the region 1930–1985 cm⁻¹ that is characteristic of the cluster/support combination. The activities of these catalysts for reactions of hydrogen with ethene, carbon monoxide, carbon dioxide, and ethane, relate to their characteristic CO stretching frequencies, giving ‘volcano’ curves. Evidence from ethene hydrogenation kinetics confirms that the characteristic CO-frequency is a monitor of strength of adsorption at the catalytically active site. Dedicated to Professor Pál Tétényi on the occasion of his 70th birthday     

一系列含T-型二维液晶基元的液晶高分子配体的合成

以４,４′ （α,ω 亚烷基二酰氧）二苯甲酰氯和２,４ 二羟基 ４′ 烷氧基偶氮苯为单体,通过溶液聚合,合成了一系列新的含Ｔ 型二维液晶基元的液晶高分子配体．单体的结构通过元素分析、ＩＲ、１Ｈ ＮＭＲ和ＭＳ等方法确证．高分子配体通过ＧＰＣ、ＤＳＣ、ＴＧ、ＷＡＸＤ和偏光显微镜等方法测试表征,发现所有的高分子配体加热至各自的熔点以上都能形成液晶态,在液晶态可以观察到向列型的丝状织构和纹影织构．它们的熔点（Ｔｍ）和液晶态的清亮点（Ｔｉ）随分子中末端烷氧基增大和柔性间隔段长度增加呈规律性变化．特别值得一提的是,发现末端不含取代基的高分子配体也能产生液晶态,这对该类高分子液晶态生成的机制与液晶态的织构提供了一个新的研究课题［１］．     

Design, syntheses and biological activity of novel ALS inhibitors (Ⅸ)——CoMFA of sulfonylureas and triazolopyrimidine-2-sulfonamides ALS inhibitors

Quantitative structure-activity relationships for herbicidal activity against rape of sulfonylurea and triazolopyrimidin-2-sulfonamide derivatives were examined three-dimensionally using comparative molecular field analysis (CoMFA). The CoMFA results show that the slopes in steric and electrostatic fields around the molecule were significant for both series in governing the potency variations in herbicidal activity. Based upon the successful superposition between the two series, the herbicidal activity was analyzable with a single equation for the combined set of compounds, which suggested that the two different series of compounds have a common region of the receptor site.     

含72元环的二维网状结构超分子配合物的合成与结构

用自组装方法合成具有特殊网状结构及光学、电学、磁学、离子或分子交换、催化等性能的化合物的分子工程学和超分子化学近年来成为人们研究的热点,并已取得了很大进展［１,２］．当前常用的一种三角架结构单元是刚性芳基三角架配体［３～５］,而对柔性芳基三角架配体及...     

NAD(P)H辅酶模型物结构与反应性关系的研究──3-位酰基的电子效应

合成了一系列3酰胺基氮取代的NAD(P)H模型物,测定了其与5硝基异喹啉正离子的二级反应速率常数,并与模型物的氧化还原电势进行了比较.实验结果表明,模型物3位酰基氧一方面可离域二氢吡啶环上N的电子;另一方面负电性的3位酰基氧在反应过渡态中又可引起分子内和分子间的两种静电作用;3位酰基的电子效应对模型物动力学反应性的影响是这两种效应综合作用的结果.