neptunium

名词 neptunium:

1. a radioactive transuranic metallic element; found in trace amounts in uranium ores; a by-product of the production of plutonium
   同义词：Np, atomic number 93

nep.tu.ni.um

n.Symbol Np （名词）符号 Np
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. 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20万年。见于铀矿的示踪量中，由核反应合成生产出来参见 element

来源：
After the planet Neptune [from the fact that it follows uranium in the periodic table]
源自 Neptune [来自于在周期表里，从它位于铀元素之后的事实]