neptunium

n. radioactive metallic element extracted from uranium ores which is a by-product of plutonium production (Chemistry)

Neptunium (IPA: ) is an element in the periodic table that has the symbol Np and atomic number 93. A silvery   radioactive metallic element, neptunium is the first transuranic element and belongs to the actinide series. Its most stable isotope, 237Np, is a by-product of nuclear reactors and plutonium production and it can be used as a component in neutron detection equipment. Neptunium is also found in trace amounts in uranium ores.
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Noun
1. a radioactive transuranic metallic element; found in trace amounts in uranium ores; a by-product of the production of plutonium
(synonym) Np, atomic number 93
(hypernym) metallic element, metal

n. neptunium, radioactive metallic element extracted from uranium ores which is a by-product of plutonium production (Chemistry)

n. neptunium, radioactive metallic element extracted from uranium ores which is a by-product of plutonium production (Chemistry)