GB/T 18115.4-2021稀土金属及其氧化物中稀土杂质化学分析方法 第4部分:钕中镧、铈、镨、钐、铕、钆、铽、镝、钬、铒、铥、镱、镥和钇量的测定Chemical analysis methods of rare earth impurities in rare earth metals and their oxides. Part 4: Determination of lanthanum, cerium, praseodymium,samarium, europium, gadolinium,

GB/T 18115.4-2021稀土金属及其氧化物中稀土杂质化学分析方法 第4部分:钕中镧、铈、镨、钐、铕、钆、铽、镝、钬、铒、铥、镱、镥和钇量的测定Chemical analysis methods of rare earth impurities in rare earth metals and their oxides. Part 4: Determination of lanthanum, cerium, praseodymium,samarium, europium, gadolinium, terbium,dysprosium, holmium, erbium，thulium, ytterbium, lutetium and yttrium contents in neodymium metal and oxide