occurrence of amino acid的用法和樣例：
例句
- Ion exchange is used extensively for the separation and purification of amino acids.
摘要離子交換法廣泛用于氨基酸的分離純化。 - Mixtures of amino acids are analyzed by first separating the mixture into components through ion-exchange chromatography.
氨基酸的混合物的分析可以首先通過(guò)離子交換層析分離為各個(gè)組分。
