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101.
102.
Two systems of 1: 1 inclusion of host β-cyclodextrin and guest p-cresol in nano-drip including 427 H2O molecules and in vacuum have been studied by the constrain molecular dynamics simulation technique with pcff force field and Rattle bond algorithm. The analysis on the dynamic structure of inclusion and radial distribution function of several kinds of oxygen atoms shows that the CD inclusion was stable during the simulation time period in two systems and none of water molecule was found to move into the CD cavity in the drip within 200 ps which conformed the hydrophobic property of CD cavity. In the drip,an obvious hydration caused by H-bonding existing in the CD hydrophilic outsides was observed,and it agreed well with the CD properties. The obvious H-bonding interactions existing between phenyl hydroxyl and water molecules in the drip and between phenyl hydroxyl and CD cavity in vacuum made the guest molecule insert into the CD cavity shallower in drip case than in vacuum case. It was concluded that the constrain molecular dynamics simulation technique can be used to investigate the dynamic behavior of CD aqueous solution. 相似文献
103.
王银邦 《应用数学和力学(英文版)》2004,25(2):152-157
The interaction between an elastic rectangular inclusion and a kinked crack inan infinite elastic body was considered by using boundary element method. The new complexboundary integral equations were derived. By introducing a complex unknown function H(t)related to the interface displacement density and traction and applying integration by parts,the traction continuous condition was satisfied automatically. Only one complex boundaryintegral equation was obtained on interface and involves only singularity of order l/ r. Toverify the validity and effectiveness of the present boundary element method, some typicalexamples were calculated. The obtained results show that the crack stress intensity factorsdecrease as the shear modulus of inclusion increases. Thus, the crack propagation is easiernear a softer inclusion and the harder inclusion is helpful for crack arrest. 相似文献
104.
The antiplane problem of circular arc rigid line inclusions under antiplane concentrated force and longitudinal shear loading was dealt with. By using RiemannSchwaz‘s symmetry principle integrated with the singularity analysis of complex functions, the general solution of the problem and the closed form solutions for some important practical problems were presented. The stress distribution in the immediate vicinity of circular arc rigid line end was examined in detail. The results show that the singular stress fields near the rigid inclusion tip possess a square-root singularity similar to that for the corresponding crack problem under antiplane shear loading, but no oscillatory character. Furthermore, the stresses are found to depend on geometrical dimension, loading conditions and materials parameters. Some practical results concluded are in agreement with the previous solutions. 相似文献
105.
106.
本文综述了基于环糊精包结络合作用的大分子自组装的研究进展,包括:(1) 线型、梳型、多臂星型或超支化聚合物与环糊精或其二聚体自组装形成多聚轮烷(分子项链)、多聚准轮烷、双多聚(准)轮烷、分子管、双分子管、超分子凝胶及其应用;(2)桥联环糊精与桥联客体分子自组装制备线型或超支化超分子聚合物;(3)温度、pH值、光及客体分子刺激响应智能体系; (4) 通过亲水性的环糊精线型均聚物与含金刚烷的疏水性聚合物之间的包结络合作用来制备高分子胶束及其空心球等。 相似文献
107.
天然流体包裹体中甲烷水合物生成条件原位变温拉曼光谱研究 总被引:9,自引:0,他引:9
准确获取流体包裹体中气体水合物的生成条件一直是传统包裹体分析方法面临的一个难题。文章采用原位拉曼光谱技术分析了天然流体包裹体中甲烷水合物的生成条件。并由常温拉曼光谱分析表明,研究流体包裹体的流体组成为CH4-H2O体系。通过三种方法控制实验温度的变化,在第三种方法实验条件下获得了-170 ℃时甲烷水合物与冰的拉曼光谱,逐渐升温原位观测甲烷水合物的消失温度。原位拉曼光谱检测结果表明,研究包裹体中甲烷水合物的生成温度为7.5 ℃。结合CH4-H2O体系水合物形成条件相平衡计算,得到包裹体中甲烷水合物生成时的压力为5.587 3 MPa。研究结果表明,原位拉曼光谱技术是准确获取流体包裹体种气体水合物生成条件的一种有效方法。 相似文献
108.
IntroductionWiththedevelopmentofparticleandfiberreinforcedcomposites,theinclusion_crackinteractionproblemisbecominganimportantfieldbeingstudied .Andasamodel,itisalsousedtostudytheeffectsofmaterialdefectsonthestrengthandfractureofengineeringstructure.TheinterationbetweencircularinclusionandcrackwasstudiedinRefs.[1 -6 ] ;InRefs.[7-1 2 ] ,theinterationbetweenlineinclusionandcrackswasdiscussed ;TheinterationbetweenellipticalinclusionandcrackwasstudiedinRefs.[1 3,1 4] .However,withthedevelopmento… 相似文献
109.
研究了三角形弹性夹杂和裂纹之间的相互影响问题。应用Chau和Wang导出的面力边值问题的边界积分方程为基本方程,用夹杂和基体交界面上的面力和位移的连续性条件为补充方程,从而得到了一组能够解决夹杂和裂纹相互影响问题的方程,最后的方程组用一种新的边界单元法求解。计算了各种不同的夹杂和基体的材料常数以及夹杂和基体之间不同距离情况下裂纹尖端的应力强度因子。文中结果对研究新型复合材料有一定的应用价值。 相似文献
110.
The purpose of this paper is to present an iterative scheme for finding a common element of the set of solutions to the variational inclusion problem with multivalued maximal monotone mapping and inverse-strongly monotone mappings and the set of fixed points of nonexpansive mappings in Hilbert space.Under suitable conditions, some strong convergence theorems for approximating this common elements are proved. The results presented in the paper not only improve and extend the main results in Korpelevich(Ekonomika i Matematicheskie Metody,1976,12(4):747-756),but also extend and replenish the corresponding results obtained by Iiduka and Takahashi(Nonlinear Anal TMA,2005,61(3):341-350),Takahashi and Toyoda(J Optim Theory Appl,2003, 118(2):417-428),Nadezhkina and Takahashi(J Optim Theory Appl,2006,128(1):191- 201),and Zeng and Yao(Taiwanese Journal of Mathematics,2006,10(5):1293-1303). 相似文献