| 释义 |
element 104n.（名词）- An artificially produced radioactive element with atomic number 104 whose isotopes have mass numbers of 257, 259, 260, and 261 with half lives respectively of 0.5, 3, 0.1, and 70 seconds.104号元素：用人工提取的放射性元素，它的原子序数是104，它的同位素的原子量是257、259、260和261，它们的半衰期分别是0.5、3、0.1和70秒
|