Three kinds of certified reference materials of pyrethroid( deltamethrin Cypermethrin fen-valcrate) have been prepared by recrystallization, and their homogeneity, stabilities and purities studied by GC and HPLC.

• 用重结晶方法制备三种除虫菊酯农药标准物质:溴氰菊酯、氰菊酯、戊菊酯,并采用二种准确可靠的分析方法:气相色谱法和液相色谱法,对它们的均匀性、定性和定值方法进行了研究。