气流不稳的

The conditional symmetry instability is the intermediate process between the stable and instable states of the atmosphere. The evolution of the atmosphere from the stable to unstable state or from unstable to stable state comes through two stages. The convective-symmetric instability circulation is related with the state and type of the instability. When the conditional instability lies in the lower level and conditional symmetric instability in the upper level, the circulation will have vertical updrafts in the lower level and slantwise updrafts in the upper level. The release of conditional symmetric instability gives rise to a mesoscale rain belt.

结果表明：条件对称不稳定是大气稳定状态和条件不稳定状态之间的中间纽带，大气由稳定向不稳定或者由不稳定向稳定的演变均通过条件对称不稳定来实现；对流对称不稳定环流的形成与不稳定层的配置有关，当低层为条件不稳定而高层叠加深厚的条件对称不稳定时，对流对称不稳定环流低层出现垂直上升气流，高层出现范围较广的倾斜上升气流，对称不稳定能量释放产生中尺度云带。

The research contents and main conclusions are as follows:1. The present thesis adopted one-dimension interior ballistic model, regarding the ballistic spatial core as the unsteady quasi one-dimension airflow containing the friction and heat exchange between airflow and tube wall, considering the boundary layer unsteady, nonstationary condensable current; and employed the MacCormack finite difference method to write the program.

本文的研究内容及结论主要体现在以下几个方面： 1、采用了一维内弹道模型，把弹后空间的核心流部分考虑为包含气流与身管管壁发生摩擦和热交换的不稳定准一维流，边界层考虑为不稳定、非定常可压缩流，用MacCormack有限差分方法求解，编制程序进行计算，较为准确的得到了复合材料身管固壁瞬态温度场分析内边界条件所需的气流温度和对流换热系数结果。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。