粘弹性基础上粘弹性矩形厚板的固有横振

由于各向同性粘弹性的剪应力——角应变及挤压力——挤压应变的本构关系与应力——应变的本构关系相似,据此在线性粘弹性范围内建立了适合于各种粘弹性基础上粘弹性矩形厚板的普遍动力学方程,从而得到了Kelvin基础上VanDerPoel模型矩形厚板的固有频率解析式。     

浅议粘弹性表面活性剂研究进展及运用

表面活性剂日益广泛的应用源于其内在的分子结构二重性特征,也即,由亲水的极性基团和疏水的非极性基团两个部分组成的化合物。本文将粘弹性表面活性剂溶液的微观结构、作用机理及其在油田中运用现状并对其提出一些展望。     

Existence and uniqueness theorem for flow and heat transfer of a non-Newtonian fluid over a stretching sheet

Analysis is carried out to study the existence, uniqueness and behavior of exact solutions of the fourth order nonlinear coupled ordinary differential equations arising in the flow and heat transfer of a viscoelastic, electrically conducting fluid past a continuously stretching sheet. The ranges of the parametric values are obtained for which the system has a unique pair of solutions, a double pair of solutions and infinitely many solutions.     

面向越野通过性虚拟试验的有限元轮胎模型

为了评价越野车辆通过性能力,分析了胎压与轮胎刚度之间的线性关系和轮胎材料的粘弹性特性对轮胎垂向力分布的影响,提出了用系数修正胎压对刚度和有效接地面积影响提高精度的方法.推导了三参数标准线性粘弹性模型的本构关系,得到了四节点等参单元有限元的刚度矩阵,建立了轮胎平面应力状态下的有限元模型.以轮胎六分力传感器为核心构建了轮胎模型的标定和验证系统,通过试验测得了不同车速工况下的车轮垂向力.试验结果验证了所提出的轮胎模型的正确性.     

用DMTA(Ⅳ)测试及分析高聚物的动态粘弹性

阐述了用动态热机械分析仪(DMTA(Ⅳ))测试高聚物动态粘弹性的原理。基于典型实例的测试结果，探讨了DMTA(Ⅳ)在测试与分析高聚物动态粘弹性中的应用。     

Bifurcation and chaos of a 4-side fixed rectangular thin plate in electromagnetic and mechanical fields

We studied the problem of bifurcation and chaos in a 4-side fixed rectangular thin plate in electromagnetic and mechanical fields. Based on the basic nonlinear electro-magneto-elastic motion equations for a rectangular thin plate and the expressions of electromagnetic forces, the vibration equations are derived for the mechanical loading in a steady transverse magnetic field. Using the Melnikov function method, the criteria are obtained for chaos motion to exist as demonstrated by the Smale horseshoe mapping. The vibration equations are solved numerically by a fourth-order Runge-Kutta method. Its bifurcation diagram, Lyapunov exponent diagram, displacement wave diagram, phase diagram and Poincare section diagram are obtained.     

聚合物力学损耗测量方法点评

聚合物力学损耗测量方法分静态法和动态法两类，本文指出这些测量方法的适用范围，并提出用静态法测量聚合物的蠕变和应力松驰验证慢响应存在于聚合物力学特性中。     

Three-dimensional nonlinear analysis of creep in concrete filled steel tube columns

INTRODUCTION Creep is an internal characteristic of concrete under long-term load. A long time has elapsed since the first discovery of concrete creep in 1907 by Hatt. Many researches have been devoted to this complex problem ever since. However, despite major suc-cesses, the creep phenomenon is still far from being fully understood, even though the phenomenon has occupied some of the best minds in the field, such as Glanville, Dischinger, Troxell, Pickett, Neville, etc. Creep phenome…     

各向异性介质中的谐和粘弹性波衰减特性分析

研究了各向异性介质中的谐和粘弹性波的衰减特性，并利用其特征值理论证明了粘弹性介质总是耗散的，在其中传播的波将以指数形式衰减，即耗散介质总具有线性稳定性，而且随着阻尼的增大，介质消耗的能量将越大，波矢量的虚实部比是介质耗散大小的度量。