promethium


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Related to promethium: Prometrium

pro·me·thi·um

 (prə-mē′thē-əm)
n. Symbol Pm
A radioactive element of the lanthanide series that is prepared by fission of uranium or by neutron bombardment of neodymium and has over 30 isotopes, the most stable of which have half-lives of 2.62 years (Pm-147), 5.53 years (Pm-146), and 17.7 years (Pm-145). Promethium-147, the most easily obtained isotope, is used as a source of beta rays. Atomic number 61; melting point 1,042°C; boiling point 3000°C; specific gravity 7.264 (25°C); valence 3. See Periodic Table.

[From Prometheus.]
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.

promethium

(prəˈmiːθɪəm) or

prometheum

n
(Elements & Compounds) a radioactive element of the lanthanide series artificially produced by the fission of uranium. Symbol: Pm; atomic no: 61; half-life of most stable isotope, 145Pm: 17.7 years; valency: 3; melting pt: 1042°C; boiling pt: 2460°C (approx.)
[C20: New Latin from Prometheus]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

pro•me•thi•um

(prəˈmi θi əm)

n.
a rare-earth, metallic, trivalent element. Symbol: Pm; at. no.: 61.
[1948; Promethe (us) + -ium2]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

pro·me·thi·um

(prə-mē′thē-əm)
Symbol Pm A radioactive metallic element of the lanthanide series. Promethium does not occur in nature, but it can be found as a product of the fission of uranium. It has 17 isotopes, one of which can be used to make miniature batteries that work at extreme temperatures for up to five years. Atomic number 61. 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.promethium - a soft silvery metallic element of the rare earth group having no stable isotopepromethium - a soft silvery metallic element of the rare earth group having no stable isotope; was discovered in radioactive form as a fission product of uranium
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
promethium
promethium
prometio
promeetium
prometium
prométhéumprométhium
prometij
promécium
prómetín
promezio
プロメチウム
prometium
prometis
promethium
promet
promécio
promeţiu
promethium
prometij
prometium
prometyum

promethium

n (Chem) → Promethium nt
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007
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Gringo, 15, PS19.99 RICHARD Rusk (Joel Edgerton) and Elaine Markinson are co-presidents of pharmaceutical company Promethium, who are poised to initiate full production of medical marijuana pill Cannabax.
Atomic number 58 (Cerium) is the most abundant REE and is more common in the Earth's crust than copper or lead and all REEs, except Atomic number 61 (Promethium) are most abundant on average in the earth's crust than silver, gold, or platinum.
However, upon revisiting the data, the use of technology (computer, Promethium Board, and iPad) was coded 18% of the total time.
Technetium (Tc), promethium (Pc), and elements heavier than uranium don't have stable isotopes and are therefore blacked out or excluded.
The lanthanides are categorised as light REs composed of elements with atomic numbers Z = 57 (lanthanum, La) to 61 (promethium, Pm), the medium RE elements ranging from Z = 62 (samarium, Sm) to Z = 64 (gadolinium, Gd), and lastly, the heavy RE elements include Z = 65 (terbium, Tb) through to Z = 71 (lutetium, Lu) [4].
The facilities include large touch screen computers, Promethium Tables, a suite of Windows tablets and green screen equipment all merged with an exciting external area consisting of chess boards, outdoor games, a diary room and private reading areas.
All the elements (except promethium; Pm) exist naturally in soil parent materials and total concentrations in soil vary from 16 to 219 mg [kg.sup.-1] (Hu et al.