neptunium


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nep·tu·ni·um

 (nĕp-to͞o′nē-əm, -tyo͞o′-)
n. Symbol 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 2.1 million years. Found in trace quantities in uranium ores, it is produced synthetically by nuclear reactions. See Periodic Table.

[After the planet Neptune (from the fact that it follows uranium in the periodic table).]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

neptunium

(nɛpˈtjuːnɪəm)
n
(Elements & Compounds) a silvery metallic transuranic element synthesized in the production of plutonium and occurring in trace amounts in uranium ores. Symbol: Np; atomic no: 93; half-life of most stable isotope, 237Np: 2.14 × 106 years; valency: 3, 4, 5, or 6; relative density: 20.25; melting pt: 639±1°C; boiling pt: 3902°C (est)
[C20: from Neptune2, the planet beyond Uranus, because neptunium is the element beyond uranium in the periodic table]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

nep•tu•ni•um

(nɛpˈtu ni əm, -ˈtyu-)

n.
a short-lived radioactive transuranic element produced in nuclear reactors by the neutron bombardment of U-238. Symbol: Np; at. no.: 93; at. wt.: 237.
[1940–45; Neptune + -ium2]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

nep·tu·ni·um

(nĕp-to͞o′nē-əm)
Symbol Np A silvery, radioactive metallic element of the actinide series. It occurs naturally in minute amounts in uranium ores and is produced artificially as a by-product of plutonium production. The most stable isotope of neptunium has a half-life of 2.1 million years. Atomic number 93. See Periodic Table.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.neptunium - a radioactive transuranic metallic elementneptunium - a radioactive transuranic metallic element; found in trace amounts in uranium ores; a by-product of the production of plutonium
metal, metallic element - any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
Translations
нептуний
neptunium
neptunium
neptunio
neptuunium
neptunium
neptunium
neptunij
neptúnium
nettunio
ネプツニウム
neptunium
neptunium
neptun
neptuniu
neptunium
neptunij
neptunium
neptünyum

neptunium

[nepˈtjuːnɪəm] Nneptunio m
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005

neptunium

n (Chem) → Neptunium nt
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007
References in periodicals archive ?
Hynes et al., "X-ray absorption spectroscopy studies of reactions of technetium, uranium and neptunium with mackinawite," Journal of Environmental Radioactivity, vol.
Properties of four natural decay series of actinides [2] Series Initial Half-life, Stable nuclide years endmember Thorium [sup.232]Th 1.405 x [10.sup.10] [sup.208]Pb Neptunium [sup.237]Np 2.140 x [10.sup.6] [sup.209]Bi Uranium [sup.238]U 4.470 x [10.sup.9] [sup.206]Pb Actinium [sup.235]U 7.038 x [10.sup.8] [sup.207]Pb Table 2.
Transfer of polonium, neptunium, plutonium and americium to the primate fetus.
They outline the important thermophysical properties of neptunium dioxide, the vapor pressure, and heat capacity; the results of a study on the vaporization behavior and phase relations in the plutonium oxide system; the vapor pressure of pure americium oxide samples; the variation of the total pressure of plutonium and americium bearing species over the solid solutions; and mass spectrometric investigations of candidate fuels and targets for transmutation of minor actinides.
MST exhibits excellent performance to remove dissolved strontium, plutonium, neptunium and uranium from highly alkaline salt solutions such as the high-level nuclear waste solutions stored at the Savannah River Site from fuel reprocessing operations.
Washington, Mar 18 (ANI): Neptunium, a waste product from uranium reactors, could pose a serious health risk should it ever seep its way into groundwater - even five million years after it is deposited at a dump.
(52) Partitioning means the separation of minor actinides, e.g., plutonium, americium, curium or neptunium from the spent fuel or HLW.
analyzing neptunium exposure through urine samples would be too
West Lake's thorium-230 and actinium-227 have been ranked along with plutonium, americium and neptunium as among the most radioactively dangerous materials known.