Nonlinear three-wave equation for a polydisperse gas-liquid mixture

A new nonlinear three-wave equation of the sixth order for pressure in a polydisperse gas-liquid mixture with bubbles of two sizes is obtained, and its stationary solutions are analyzed. The equation includes two nonlinear quadratic terms of different derivative orders. These terms are of fundamental importance for obtaining good correspondence between the solutions to this equation and the experimentally observed solitary waves in the form of two coupled solitons.     

高聚物PMMA的受力变形行为与粘弹－塑性本构理论模型

对高聚物ＰＭＭＡ实验测定了不同（Ｔ，ε）的单轴加卸载循环的应力－应变曲线。讨论了应力促进热激活塑性变形的活化粘壶理论和塑性变形的发展规律。提出由ＳＬＳ或ＭＳ与活化粘壶作串联耦合的粘弹－塑性本构理论模型，给出了微分和积分形式的本构方程组，用于拟合求解加卸载循环的应力－应变曲线，获得良好吻合的结果。详细讨论了ＰＭＭＡ在加载过程中的受力变形行为，包括起始加载的粘弹性变形，ε＿ｖ和ε＿ｐ的互相挤占，屈服点，以及屈服后应变软化和硬化的抗衡过程。对应变软化－硬化效应提出一种新的起因于粘弹变形内禀滞后效应的理论解释，并定名为粘弹软化－强化效应。对所包含的粘弹变形成分，从Ｅ＿ｖ的移位因子和归一化应力－应变主曲线两方面，讨论了可能存在的率温等效关系。     

Establishment of The Power—Time Curve Equation of Bacterial Growth in the Log Phase

The power-time curves of two species of bacteria, Vibro metschnikovii, Vibro bollisae were determined calorimetrically by using a 2277 bioactivity monitor. The power-time curve equation of bacterial growth in the log phase can be expressed as

环上矩阵的Moore-Penrose逆的注记

讨论带有对合反自同构的环上矩阵的广义逆,给出了矩阵存在Mooore－Penrose逆的条件及Moore－Penrose逆的一些性质和显式．     

一类三阶自治系统的积分法

研究一类三阶自治系统的积分方法,证明了在一定条件下,这类系统的积分问题归结为求解由该方程的系数所确定的Riccati方程     

一阶时滞微分方程解的零点分布

Abstract. The paper gives two estimates of the distance between adjacent zeros of solutions     

Oscillation and Nonoscillation Criteria for a Second Order Linear Equation

New oscillation and nonoscillation criteria are established for the equation

On the Dirichlet Problem in a Characteristic Rectangle for Fourth Order Linear Singular Hyperbolic Equations

In the rectangle D = (0,

Some rapidly converging series for

For a natural number , the author derives several families of series representations for the Riemann Zeta function . Each of these series representing converges remarkably rapidly with its general term having the order estimate:

Relevant connections of the results presented here with many other known series representations for are also pointed out.

     

approximations of inertial manifolds via finite differences

We construct an inertial manifold for the evolution equation as a limit of the inertial manifolds for the difference approximations of the Trotter-Kato type and show that this limit is taken in a topology.