| 单词 | 铀矿 |
| 释义 | 〔plutonium〕A naturally radioactive, silvery, metallic transuranic element, occurring in uranium ores and produced artificially by neutron bombardment of uranium. Its longest-lived isotope is Pu 244 with a half-life of 76 million years. It is a radiological poison, specifically absorbed by bone marrow, and is used, especially the highly fissionable isotope Pu 239, as a reactor fuel and in nuclear weapons. Atomic number 94; melting point 640°C; boiling point 3,235°C; specific gravity 19.84; valence 3, 4, 5, 6. See table at element 钚：一种天然地放射性银色超铀金属元素，存在于铀矿中，对铀元素进行中子轰击而人工制成。其存在周期最长的同位素是半衰期为七千六百万年的钸244，它是一种核辐射毒素，特别是能被骨髓吸收。尤其是其极具可裂变性的同位素钸239，被用作一种核反应燃料并用在核武器中。原子序数94；熔点640°C；沸点3,235°C；比重19.84；化合价3, 4, 5, 6 参见 element〔yellowcake〕The concentrated oxide of uranium formed in the milling of uranium ore.黄饼：在铀矿提炼时形成的浓缩铀氧化物〔pitchblende〕A massive variety of the mineral uraninite.沥青铀矿：铀矿的一种〔actinium〕A radioactive element found in uranium ores, used in equilibrium with its decay products as a source of alpha rays. Its longest lived isotope is Ac 227 with a half-life of 21.7 years. Atomic number 89; melting point 1,050°C; boiling point (estimated) 3,200°C; specific gravity (calculated) 10.07; valence 3. See table at element 锕：一种在铀矿中发现的放射性元素，作为阿尔法射线能源增入点用于与其衰变产物的平衡过程中，其最长的活同位素是半衰期为21.7年的锕227。原子序数为89；熔点为1,050摄氏度；（估计的）沸点为3,200摄氏度；（计算出的）比重为10.07；原子价为3 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〔scandium〕A silvery-white metallic element found in various rare minerals and separated as a byproduct in the processing of certain uranium ores. An artificially produced radioactive isotope is used as a tracer in studies of oil wells and pipelines. Atomic number 21; atomic weight 44.956; melting point 1,540°C; boiling point 2,850°C; specific gravity 2.99; valence 3. See table at element 钪：一种发现于许多稀有矿物中的银白色金属元素，是某种铀矿加工过程中分离出的副产品，人造放射性同位素被用作油井和油气管道的探测剂。原子序数21；原子量44.956；熔点1,540°C；沸点2,850°C；比重2.99；化合价3 参见 element |
| 随便看 |
|
英汉汉英双解词典收录301015条英汉双解翻译词条，可根据汉字查询相应的英文词汇，基本涵盖了全部常用汉字的英文读音、翻译及用法，是英语学习及翻译工作的有利工具。