uranium
uranium
[j??re?n??m]
noun
adjective
語源
[j??re?n??m]
noun
- [mass noun]the chemical element of atomic number 92, a grey dense radioactive metal used as a fuel in nuclear reactors(Symbol: U)
鈾(（符號(hào)：U）) - Uranium is a chemically reactive metal belonging to the actinide series. Becquerel discovered radioactivity in uranium in 1896, and its capacity to undergo fission led to its use as a source of energy, though the fissile isotope, uranium-235, has to be separated from the more common uranium-238 before it can be used in nuclear weapons. The atom bomb exploded over Hiroshima in 1945 contained uranium-235
adjective
語源
- late 18th cent.: modern Latin, from Uranus: compare with tellurium
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