超痕量 meaning in English

ultra trace
ultratrace level

Laser - induced fluorescence detection in ultratrace analysis
超痕量分析中的激光诱导荧光检测
Determination of ultra - trace platinum in rock samples by gf - aas method
石墨炉原子吸收测定岩石样品中超痕量铂
Flow injection catalytic spectrophotometric method for determination of ultratrace nitrite
反相流动注射催化光度法测定超痕量亚硝酸根
Determination of ultra - trace rare earth elements in biological samples by inductively coupled plasma mass spectrometry
电感耦合等离子体质谱测定生物样品中超痕量稀土元素
Determination of ultratrace precious metals and rhenium in geological samples by inductively coupled plasma mass spectrometry
等离子体质谱法测定地质样品超痕量贵金属和铼