Under the careful retrospection and analysis on the previous and recent experiments about mechanical behavior of nanocrystalline metals performed by almost main investigators , the dislocation and atomic diffusion is believed to contribute hardly to the deformation of nanocrystalline alloy , and a model based on thermal activation process was applied to fit the experimental data of nanocrystalline ag 结果表明，纳米晶金属ag的不仅具有比粗晶ag高2 - 6倍的拉伸和压缩强度，而且在大范性形变阶段显示了极低的加工硬化和应变速率敏感性。结合位错理路和非晶合金形变特征，提出纳米晶金属ag的塑性变形主要由于晶界滑移贡献。
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But in fact , teacher movement of middle school has lost clearly regulations in vast countryside of developing area . it has affected seriously the stability of the teachers of this area , made many teachers leave and the education worse and worse 可是，在现实中，我国经济欠发达地区的广大农村中学教师流动已明显呈现出盲目性、单向性和失范性的特点，它严重地影响了该地区教师队伍的稳定性，造成了大量教师的流失，对本来就处于薄弱环节的经济欠发达地区的农村教育，无疑是雪上加霜。
