| 单词 | 超铀元素 |
| 释义 | 〔nobelium〕A radioactive transuranic element in the actinide series, artificially produced in trace amounts. Its longest-lived isotope is No 255 with a half-life of 3 minutes. Atomic number 102. See table at element 锘：在锕类元素中的一种放射性超铀元素，人工微量制造，其最长寿命的同位素是锘255，其半衰期为三分钟，原子序数102 参见 element〔lawrencium〕A short-lived, radioactive synthetic transuranic element produced from californium and having isotopes with mass numbers 255 through 260 and half-lives of a few seconds to three minutes; atomic number 103. See table at element 铹：一种寿命期短的、人工合成的放射性超铀元素，从锎中生成，有质量从255到260的同位素，半衰期从几秒钟到三分钟；原子序数103 参见 element〔einsteinium〕A synthetic transuranic element first produced by neutron irradiation of uranium in a thermonuclear explosion and now usually produced in the laboratory by irradiating plutonium and other elements. Its longest-lived isotope is Es 254 with a half-life of 276 days. Atomic number 99; melting point 860°C. See table at element 锿：一种人工合成超铀元素，在一次热核子反应的铀中子辐射中首次产生。 现在通常通过在实验室里辐照钚和其它元素而产生，其最不易衰变的同位素是Es254， 它的半衰期为276天，原子序数99；熔点860°C 参见 element〔neptunium〕A silvery, metallic, naturally radioactive element, atomic number 93, the first of the transuranium elements. Its longest-lived isotope is Np-237 with a half-life of 2.1 million years. Found in trace quantities in uranium ores, it is produced synthetically by nuclear reactions. See table at element 镎：一种银白色的、金属性天然放射性元素，原子序数为93，第一个超铀元素。其周期最长的同位素为Np-237，半衰期为210万年。见于铀矿的示踪量中，由核反应合成生产出来 参见 element〔mendelevium〕A synthetic radioactive transuranium element of the actinide series. Atomic number 101; mass numbers 255 and 256; half-lives approximately 30 minutes (Md 255) and 1.5 hours (Md 256). See table at element 钔：锕系之合成放射性超铀元素。其原子序数为101；质量数为255和256；半衰期大约为30分钟（质量数为255的元素），及一个半小时（质量数为256的元素） 参见 element |
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