Home / Standards / GB 223.37-89 GB 223.37-89 Steel and alloy—Determination of nitrogen content by distillation separation-indophenol blue photometric method 钢铁及合金化学分析方法 蒸馏分离一靛酚蓝光度法测定氮量 Standard Type GB ICS N/A CCS N/A Status N/A Issue Date N/A Implementation N/A Responsible Dept N/A Drafting Unit N/A