| 单词 | 十四个 |
| 释义 | 〔technetium〕A silvery-gray radioactive metal, the first synthetically produced element, having 14 isotopes with masses ranging from 92 to 105 and half-lives up to 2.6×106 years. It is used as a tracer and to eliminate corrosion in steel. Atomic number 43; melting point 2,200°C; specific gravity 11.50; valence 0, 2, 4, 5, 6, 7. See table at element 锝：一种银灰色放射性金属，是第一个人工合成的元素，有十四个原子量从92到105且半衰期高达2.6×106年的同位素。用作放射追踪剂并可消除钢铁腐蚀现象。原子序数43；熔点2,200°C；比重11.50；原子价0, 2, 4, 5, 6, 7 参见 element〔promethium〕A radioactive rare-earth element prepared by fission of uranium or by neutron bombardment of neodymium, having 14 isotopes with mass numbers ranging from 141 to 154 and used as a source of beta rays. Atomic number 61; melting point 1,168°C; boiling point 2,460°C; valence 3. See table at element 钜：放射性稀土元素，由铀分裂或钛的中子爆炸而成，有十四个拥有从141到154的质量数的同位素，用作β射线源。原子序数61；熔点1,168°C；沸点2,460°C；原子价为3 参见 element〔fourteen〕Something having 14 parts, units, or members.十四一组的物品：有十四个部分、单位或成员的某物〔fortnight〕alteration of fourtene night [fourteen nights] fourtene night的变化 [十四个夜晚] |
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