一类非线性具有转点的三阶奇摄动边值问题

本文主要主类具有转点的非线性奇摄动边值问题，首先利用拓扑横截性定理和不动点原理得到了退化解和形式解的存在条件，讨论了上述解在奇点的光滑性条件，最后得到了一致有效的渐近估计。     

STUDY ON in vitro SPERM CAPACITATION AND EGG-PENETRATION OF GIANT PANDA

A preliminary report on in vitro sperm capacitation and egg-penetration of giant panda is briefly presented. The panda spermatozoon consists of head, neck and tail, just like the spermatozoa of other animals. Before capacitation sperm heads clusterd together and dispersed after capacitation. They were then able to swim straight forwared. During the time of in vitro capacitation the plasm membrane of the sperm head was first expanded tov arious degrees, then disintegrated, and finally became detached. The electro-dense material in the acrosome appeared in small clumps with high density. Extensive vesiculation occurred between the bi-layered acrosome membranes and thus led to disintegration. Vesiculation in panda sperm differs from that reported in hamsters. When the capacitated panda spermatozoa came into contact with the hamster eggs, the region between the acrosome collar and postacrosome cap first fused with the egg membrane followed by the penetration of the nucleus into the cortex of the egg. Some o     

一类奇摄动系统奇异极限环的不变环面分支

对一类奇异摄动系统中由奇异极限环产生的不变环面分支进行了研究并利用不变环面的分支理论,讨论了由快系统的二重极限环和三重环分支出的不变环面的存在性．     

大熊猫精子体外获能和异种穿卵的超显微结构研究

大熊猫精子体外获能前,精子头部发生群集成缗钱状结构,获能后精子作活跃直线的超激活运动。获能过程中头部质膜先膨胀,随后破裂,顶体内致密物质浓缩成小团块,双层顶体外膜出现囊泡化引起顶体反应,从而顶体逐渐瓦解脱落,但顶体内胰仍包在核膜之外。 大熊猫精子获能和顶体反应后并能与地鼠卵子相互作用,在顶体领与后顶体帽连接处同卵膜先开始融合,接着可以穿入卵内。地鼠卵被大熊猫精子穿入后,卵表面出现明显的异常形态变化。     

Time-delay feedback control in a delayed dynamical chaos system and its applications

The feedback control of a delayed dynamical system, which also includes various chaotic systems with time delays, is investigated. On the basis of stability analysis of a nonautonomous system with delays, some simple yet less conservative criteria are obtained for feedback control in a delayed dynamical system. Finally, the theoretical result is applied to a typical class of chaotic Lorenz system and Chua circuit with delays. Numerical simulations are also given to verify the theoretical results.     

一类奇摄动系统奇异极限环的不变环面分支

对一类奇异摄动系统中由奇异极限环产生的不变环面分支进行了研究并利用不变环面的分支理论,讨论了由快系统的二重极限环和三重环分支出的不变环面的存在性.