A quantitative analytical method for 4.5% beta-cypermethrin EC by GC was introduced, Dicyclohexyl-o-phthalate was selected as the internal standard.

• 本文介绍了以邻苯二甲酸二环已脂为内标物，对4.；5%25高效氯氰菊脂乳油进行有效成份测定的气相色谱分析法。