METHODS With 45Sc, 89Y, 115In and 209Bi as internal standard elements, the sample solutions were analyzed by ICP-MS after microwave digestion, and the contents of elements were calculated according to their calibration curves.

• 方法样品经微波消解后,以钪(45Sc)、钇(89Y)、铟(115In)、铋(209Bi) 作为内标物质,直接用ICP-MS分析上述7种元素,并通过标准曲线计算含量。