GB/T 12690.12-2003
稀土金屬及其氧化物中非稀土雜質化學分析方法 釷量的測定 偶氮胂III分光光度法和電感耦合等離子體質譜法
Chemical analysis methods for non-rare earth impurities of rare earth metals and their oxides-Determination of thorium content-Arsenazo III spectrophotometric method and inductively coupled plasma mass spectrum method
GBT12690.12-2003, GB12690.12-2003