1、浓度单位。 2、1μg = 1/1000 mg = 1/1000,000 gμg/g = (1/1000) mg/(1/1000)kg = mg/kg1μg/g = (1/1000,000)g/g = 1/1000,000 = 1 ppm。...
发布时间:2026-03-23 浏览量:0