ascending-descending chromatography

例句：

1. 1. The scientists used the ascending and descending chromatography to identify the chemical components in thesample.
   科学家们使用上升和下降的色谱法来鉴定样本中的化学成分。
2. 2. In this experiment, we applied both ascending and descending chromatography to analyze themolecular structure of the compound.
   在这个实验中，我们应用了上升和下降的色谱法来分析化合物的分子结构。
3. 3.The ascending and descending chromatography was crucial for the identification of rare compounds in the plant samples.
   上升和下降的色谱法对于在植物样本中识别稀有化合物至关重要。