Light-Gradient-Induced Spiral Wave Drifts in a Belousov-Zhabotinsky Reaction

The dynamic behaviour of spiral tip in the light-sensitive Belousov-Zhabotinsky reaction under the influence of an externally applied light gradient was experimentally studied. The gradient causes different drifts for different spiral patterns. The centre of the spiral wave moved toward the region of lower light intensity. The direction of an additional perpendicular drift depended on the chirality of the spiral wave. The dependences of the drifting angle and the drifting velocity on light gradient have been measured.     

Elimination of Spiral Waves and Competition between Travelling Wave Impulses and Spiral Waves

The interaction between travelling wave impulses and spiral waves is studied and the results of their competition are related to the exciting period. From the results, it is known that the formation and development of spiral waves in cardiac tissue depend on the period by which the travelling wave impulses are excited. A method is proposed to eliminate spiral waves, which is easily operated.     

对激光等离子体中X射线的产生与辐射加热研究

利用一维辐射流体力学程序MULTI数值模拟研究了功率为1014Wcm2、脉冲宽度为300ps、波长为0.44μm的强激光辐照平面Au靶时产生X射线的过程,给出了X射线转换效率和能谱分布.通过将靶物质划分为对所产生的X射线光学薄的转化区和光学厚的再发射区,得到了作为黑体辐射热源的最佳靶厚度,并给出了辐射加热靶所产生的等离子体的密度和温度的空间分布. 关键词： 辐射流体力学 激光等离子体 X射线转换 辐射热波     

Instability of Longitudinal Wave in Magnetized Strongly Coupled Dusty Plasma

Instability of longitudinal wave in magnetized strongly coupled dusty plasmas is investigated. The dust chargigrelaxation is taken into account. It is found that there exists threshold of interdust distance for the instability of wave, which is determined significantly by the dust charging relaxation, the coupling parameter of high correlation of dust as well the strength of magnetic field.     

关于非线性Pochhammer-Chree方程的解

本文研究了弹性杆纵向形变方程:u_(tt)—u_(ttxx)—u_(xx)—(1/3)(u~3)xx=0的椭圆余弦波解,并用Adomian分解法,求出了其初边值问题解.     

饱和土中波传播的二相动力分析模型

将饱和土作为二相介质,考虑土骨架和孔隙流体之间的摩阻力,建立了饱和土中一维压缩波传播的二相动力分析控制微分方程,采用有限差分法求解。该模型可以计算地表面爆炸冲击荷载作用下饱和土中波的传播和波在不动障碍上的反射问题。该模型可考虑饱和土土体的非线性塑性力学性质及土性随深度变化或土介质的分层情况。     

产生特殊聚焦图形的二元光学元件

通过面积编码将伽博（Gabor)波带片的透过率函数的余弦分布等效为二元分布，研制了能产生各种特殊聚焦图形的二元光学元件。根据透镜聚焦的物理原理制作的二元振幅型波带片可以方便地产生多种聚焦线，给出了相应的实验结果，并讨论了改善聚焦效果的优化条件。     

电子离子碰撞过程中的共振激发双自电离

利用相对论修正扭曲波玻恩近似, 计算了类钠离子Ti11+ 和Cr13+ 的电子碰撞直接电离, 激发自电离和共振激发双自电离截面. 理论数据与实验结果在整个能区内很好符合. 共振激发双自电离截面对总截面的贡献约为20%-30%, 对速率系数的影响较大, 不可忽略.     

延长速调管使用寿命的方法

描述了一种延长EPR波谱仪中速调管使用寿命的方法.根据这种方法,只要正确地调谐微波桥的工作状态和适当地调整功率电平器的功率校正电平.即使对于已经严重老化的速调管仍然可以继续使用一段时间,维持仪器的正常运行.