GB/T 6730.37-2017
Iron ores—Determination of cobalt content—4-[(5-chloro-2-pyridyl)azo]-1,3-diamino-benzene spectrophotometric method
HG/T 5709\uff5e5712-2020
GB/T 14506.26-1993
Silicate rocks—Determination of cobalt content—4-[(5-Chtoro-2-pyridyl)-azo]-1,3-diamino benzene photometric method
GB/T 6730.37-1986
Methods for chemical analysis of iron ores The 4-[(5-chloro-2-phridyl)azo]-1,3-diaminobenzene photometric method for the determination of cobalt content