高陡岩质边坡稳定性三维离散元分析

某高陡岩质边坡地质条件复杂、软弱结构面发育、开挖高度大、坡度陡、临空面多,为边坡变形提供了有利的空间,边坡多处出现失稳破坏迹象。通过对边坡工程地质条件调查,岩体结构特征和边坡开挖等影响因素的分析,认为边坡变形主要发生在强风化强卸荷岩体内,受软弱结构面的控制比较明显,表现为结构面组合控制的块体变形失稳破坏模式。采用3DEC数值模拟软件,模拟了边坡开挖后坡体变形特征,数值模拟结果表明,边坡浅表层块体以及控制性块体稳定性差,可能导致边坡产生整体失稳。     

川藏公路茶树山滑坡特征及成因机制分析

通过对川藏公路茶树山滑坡地质环境条件的系统调查研究,分析了滑坡岩土体结构、边界条件、变形特征、影响因素,并结合3DEC数值模拟,对其变形破坏机制进行了深入的探讨。综合分析表明,滑坡位于活动断裂带内,后缘斜坡陡峭,岩体破碎,同时前缘为较厚的松散堆积体斜坡,在地震活动、降雨等影响因素的诱发作用下,滑坡成因机制主要表现为以下3个阶段:(1)倾倒拉裂阶段,滑坡受后缘地形及岩体结构控制作用较为明显,在坡体浅表层一定深度范围内出现较为强烈的倾倒拉裂变形带,产生倾倒-拉裂滑动; (2)蠕滑变形阶段,前缘松散堆积体在强大的自重推力作用下发生蠕滑变形; (3)前部"锁骨段"剪断,整体失稳阶段,滑坡前部锁骨段在自重推力及断层活动的持续影响下,发生剪断,控制后缘倾倒拉裂体稳定性的潜在滑面与前缘松散堆积体体内的剪切滑动面贯通,滑坡整体失稳。     

A NOVEL METAL CHELATE AFFINITY ADSORBENT FOR PROTEIN UPTAKE

1. INTRODUCTION Chitosan is a hydrolyzed derivative of chitin and belongs to a family of linear unbranched polysaccharides which contain large amounts of 1,4-linked-2-amino-2-deoxy-β-D-glucan residues. The presence of free amine groups in chitosan enhances the solubility and reactivity of this polymer. Interest in modifying chitosan by using glutaraldehyde has recently increased. The derivatized polymers have been employed for many applications [1~2], including protein immobilization…     

A NOVEL METAL CHELATE AFFINITY ADSORBENT FOR PROTEIN UPTAKE

In this article,a spherical chitosan gel crosslinked by epichlorohydrin was prepared.It was then loaded with copper ions to produce a metal chelate affinity adsorbent for protein.The uptake of bovine serum albumin(BSA)by the affinity adsorbent was investigated.and the adsorption capacity for BSA as high as 40mg/g-wet beads was observed.The adsorption equilibrium data was well correlated by the Langmuir equation.The adsorption was considerably affected by pH.In additio.The amount of BSA adsorbed onto the beads decreased with the increasing of aqueous phase ionic strength,so adsorbed BAS can be desorbed by adjusting pH orionic strength of the solution.     

环糊精聚合物的高分子效应

环糊精以其独特的包络性能而引人注目, 现已广泛应用于色谱分离、选择性合成的催化剂、食品、医药及农药等多种领域。环糊精聚合物被证实亦具有包络、缓释及催化的能力, 以及较好的机械强度和化学稳定性。目前环糊精聚合物主要应用在色谱分离、空气净化和食品工业等方面。本文综述了环糊精高分子化后所表现出的高分子效应, 为环糊精聚合物的合成和应用提供参考。     

用经典Hopkinson杆测试弹性模量的初步探讨

采用一维弹性应力波理论,实现了经典Hopkinson杆试验的计算机模拟,研究了试验"测得"(重构)的应力-应变曲线的精确度,并结合具体试验进行了分析.由于经典Hopkinson杆试验的基本计算公式中引入了"应力均匀性"假设,因此在有限应变范围内,重构的应力-应变曲线总是和输入(真实)曲线差异较大.结果表明,采用经典Hopkinson杆测量的弹性模量是不可靠的,因此实践中应慎用.     

对等式约束非线性规划问题的Hestenes-Powell增广拉格朗日函数的进一步研究

本文对用无约束极小化方法求解等式约束非线性规划问题的Hestenes-Powell 增广拉格朗日函数作了进一步研究．在适当的条件下,我们建立了Hestenes-Powell增广拉格朗日函数在原问题变量空间上的无约束极小与原约束问题的解之间的关系,并且也给出了Hestenes-Powell增广拉格朗日函数在原问题变量和乘子变量的积空间上的无约束极小与原约束问题的解之间的一个关系．因此,从理论的观点来看,原约束问题的解和对应的拉格朗日乘子值不仅可以用众所周知的乘子法求得,而且可以通过对Hestenes-Powell 增广拉格朗日函数在原问题变量和乘子变量的积空间上执行一个单一的无约束极小化来获得．     

一个新的填充函数

填充函数法是一种解无约束全局极小化问题的方法.这种方法的关键是构造填充函数,在已发表的文献中已经介绍了几种填充函数.在此介绍只含一个参数的填充函数,并且根据此填充函数提出了一种填充函数算法.给出了用这种填充函数法解几个测试问题的计算结果.     

A theoretical study of electronic excited states of photosynthetic reaction center in Rhodopseudomonas viridis

As well known,photosynthesis is the most impor-tant biochemical process on the earth.With a few mi-nor exceptions,photosynthesis is the only mechanism by which an external source of energy is harnessed by the living world.As a crucial composition of photo…     

Two Novel Self-Assemblies of the Calix[4]arene Derivatives and Their Structures

Two newly identified supramolecule structures arise from self-assembly of theCalix[4]arenes derivatives 1 and 2: one ethyl ester of 1 (or 2) enters into the cavity of another 1 (or 2) forming a 1D long chain structure. The interaction force of the molecules and the crystallization energy might be an important driving force for forming theself-assembled calix[4]arene. Supplementary Data relating to this article (atomic coordinates, hydrogen coordinates, isotropic displacement parameters, anisotropic displacement parameters, selected geometrical parameters and observed and calculated structure factors) are deposited in the British Library.