unsaturated linkage的用法和樣例：
例句
- The unsaturated link occurs in a cyclic system.
在環體系中存在不飽和鍵。 - Dialkyl quaternary ammonium salts can be used as fabric softeners with high performance, their biodegradation can be improved by inducing unsaturated bond into their alkyl chain.
摘要雙烷基季銨鹽類產品是一種性能優良的織物柔軟劑，如果在烷基鏈中引入不飽和鍵，就會提高其生物降解性。
