GB/T 40394-2021
Determination of trace trimethylamine in methanol for industrial use—Gas chromatography-mass spectrometry
GB/T 6730.34-2017e
Iron ores—Determination of tin content—Pyrocatechol violet cetyl trimet hylamine bromide spectrophotometric method
GB/T 6730.34-2017
Iron ores—Determination of tin content—Pyrocatechol violet cetyl trimet hylamine bromide spectrophotometric method