metastable energy level

例句：

1. 1. The system is metastable at this temperature range.
   这个温度范围内系统是不稳定的。
2. 2. Metastable states are often associated with chemical reactions.
   亚稳态通常与化学反应有关。
3. 3. The metastable phase of the material will eventually reach a stable state.
   这种材料的亚稳态最终会达到一个稳定状态。