first stage ionization

例句：

1. 1.The first stage of the reaction is crucial for understanding its mechanism.
   反应的第一级阶段对于理解其机制至关重要。
2. 2. During the first stage, the atoms are in a highly excited state.
   在第一阶段，原子处于高度激发状态。
3. 3.The process of primary ionization is essential for the formation of new compounds.
   初级电离过程对于形成新化合物至关重要。