neptunium


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neptunium

 (Np) [nep-too´ne-um]
a chemical element, atomic number 93, atomic weight 237. (See Appendix 6.)

nep·tu·ni·um (Np),

(nep-tū'nē-ŭm),
A radioactive element; atomic no. 93; first element of the transuranian series (not found in nature); 237Np has a half-life of 2.14 × 106 years.
[planet, Neptune]

neptunium

/nep·tu·ni·um/ (Np) (nep-toon´e-um) a chemical element, at. no. 93.

neptunium (Np)

[nept(y)o̅o̅′nē·əm]
Etymology: planet Neptune
a transuranic, metallic element. Its atomic number is 93; its atomic mass is 237. Although neptunium is considered a synthetic element, traces of natural neptunium have been found in uranium ores.

nep·tu·ni·um

(nep-tū'nē-ŭm)
A radioactive element; atomic no. 93; first element of the transuranian series (not found in nature); 237Np has a half-life of 2.14 × 106 years.
[planet, Neptune]

neptunium

a chemical element, atomic number 93, atomic weight 237, symbol Np. See Table 6.
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References in periodicals archive ?
National Laboratory has measured how much neptunium it would take to make a bomb--the element's critical mass--with far greater accuracy than ever before.
In 1940 Abelson, who was helping to isolate neptunium (see above), suggested that uranium hexafluoride, with each molecule made up of one uranium atom and six fluorine atoms, was a liquid that was easily evaporated, and the vapors might then be made to pass through tubes or holes.
2 percent of current stocks are highly radioactive, but some of the material, such as neptunium 237, can remain radioactive for more than two million years, the report noted.
Since uranium had been named for the planet Uranus (see 1789), the new element, lying beyond uranium, was named neptunium, for Neptune, the planet lying beyond Uranus.
Having demonstrated a technology for extracting actinides from IFR wastes, Chang says, his team must now prove that recycled actinides will fission efficiently Late last month, they launched a two-year experiment to test just that by placing a small quantity of the actinides americium and neptunium into a fuel bundle that they inserted in an IFR-type reactor core.
Christiansen of the University of Copenhagen, studied how green rust contained neptunium, a waste product from uranium reactors that can prove dangerous to human health if it seeps into groundwater--even millions of years after it is discarded at a repository.
Though this article is concerned with elements 110-999, I couldn't help but notice that UNNILPENTIUM (element 105) and UNNILSEPTIUM (element 107) can both be transdeleted (by removal of three letters) to NEPTUNIUM (element 93), an element whose name isn't part of the new systematic convention.
Water passing over the inch-long, half-inch-diameter glassy cylinder -- containing the radionuclides neptunium, americium and plutonium-- collected in the enclosing vessel.