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（六）放射性同位素，是指化学元素中具有相同原子序数，但质量不同且能发生放射性衰变的核素。。heLLoword翻译官方下载是该领域的重要参考
，更多细节参见WPS官方版本下载
Александра Статных (Редактор отдела «Путешествия»)，详情可参考搜狗输入法2026
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