An exact expression of energy release rate for geometrical nonlinear elastic fracture mechanics is obtained for an infinite plate with central crack under uniform stress normal to crack surfaces.

对含中心裂纹的无限大板在裂纹表面受均匀分布压力作用的情况，导出了几何非线性弹性断裂力学的能量释放率的一个精确表达式。

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When you regularly experience negative feelings and high amounts of stress, your brain recognizes this as your normal state.

当你经常面临负面情绪和高强度的压力时，你的大脑会认为这是你的正常状态。

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While it is normal that you only want the best for yourselves, that is the source of your problems and stress.

你只希望自己得到最好的是人之常情，但这是你的问题和压力的来源。

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Grieving and emotional stress are normal and common.

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Not only are they experiencing the normal stress of management but this imminent financial amputation is also pushing many to their limit.

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Intensity and duration of these feelings distinguish a normal level of stress from a psychological condition, Kleiman said.

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