抽提

It shows that it is possible to increase the start oscillation length by tailoring magnetic field's amplitude and its period without changing the synchronous condition of the fundamental wave;in the meantime, when there are two or more azimuthally asymmetric space harmonics in the high power broad-band helix TWT, the influences of the Pierce's gain parameter, space charge parameter, and loss parameter on the start oscillation length and real starting asynchronous velocity parameter are also analyzed.

研究结果表明：改变聚焦磁场的幅值或周期来增加起振长度是可能的，而且不会改变基波的互作用条件。与此同时，对起振长度、初始非同步速度参量随皮尔斯增益参量、空间电荷参量、损耗参量等的变化，以及在超宽带行波管中当存在两个或多个角向非对称空间谐波时，起振长度、初始非同步速度参量随周期永久聚焦磁场的变化进行了研究。

It is proposed that the microstructure in the austenite is attached importance to the shape memory effect of the alloy.

研究发现，各合金都在特定的温度固溶处理后，呈现最佳的形状记忆效应。