separation of carbon residue from PCA

例句：

1. 1.The two countries have been at a state of permanent separation since the war.
   自战争以来，这两个国家一直处于永久分离的状态。
2. 2. The scientists separated the cells into different groups for further analysis.
   科学家们将细胞分成不同的组进行进一步分析。
3. 3. The train's departure was delayed due to the separation of the tracks.
   火车的出发因轨道分离而延迟了。