| 单词 | 在研究中 |
| 释义 | 〔americium〕A white metallic transuranic element of the actinide series, having isotopes with mass numbers from 237 to 246 and half-lives from 25 minutes to 7,950 years. Its longest-lived isotopes, Am 241 and Am 243, are alpha-ray emitters used as radiation sources in research. Atomic number 95; specific gravity 11.7; valence 3, 4, 5, 6. See table at element 镅：锕系元素中的一种白色超铀金属元素，其同位素原子序数是从237到246，半衰期从25分钟到7,950年。其寿命最长的同位素镅241和镅243在研究中用作α射线辐射源。原子序数为95；比重11.7；原子价为3,4,5,6 参见 element〔europium〕A silvery-white, soft, rare-earth element occurring in monazite and bastnaesite and used to dope lasers and to absorb neutrons in research. Atomic number 63; atomic weight 151.96; melting point 826°C; boiling point 1,439°C; specific gravity 5.259; valence 2, 3. See table at element 铕：存在于独居石和氟碳矿中一种银白色、柔软的稀有金属，在研究中常用于激光器添加剂以吸收中子。原子序数63；原子量151.96；熔点826°C；沸点1,439°C；比重5.259；化合价2,3 参见 element |
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