The first step of retention analysis is to extract and clean up the trace pesticides. 农药残留量分析的第一个环节就是从样品中提取和净化痕量农药，以便进行分析测定。
A new decentralized fault line selection installation based on transient analysis and fault recording technology is given. 给出了一种利用暂态量分析和故障录波技术的分散式新型选线装置的设计。
