promethium


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Related to promethium: Prometrium

promethium

 (Pm) [pro-me´the-um]
a chemical element, atomic number 61, atomic weight 147. (See Appendix 6.)
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

pro·me·thi·um (Pm),

(prō-mē'thē-ŭm),
A radioactive element of the rare earth series, atomic no. 61; first chemically identified in 1945; 145Pm has the longest known half-life (17.7 years).
[Prometheus, a Titan of G. myth who stole fire to give to mortals]
Farlex Partner Medical Dictionary © Farlex 2012

pro·me·thi·um

(Pm) (prŏ-mē'thē-ŭm)
A radioactive element of the rare earth series, atomic no. 61; 145Pm has the longest known half-life (17.7 years).
[prometheus, a Titan of G. myth who stole fire to give to mortals]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
When all fourteen lanthanides are considered, except promethium trichloride, there is no simple explanation for [T.sub.g] enhancement in terms of, for example, (i) cation size, (ii) number of f-electrons, (iii) ligand field stabilization, or (iv) the "gadolinium break" (4).
With the discovery of promethium, the periodic table had no further gaps, and all that remained was to discover further elements beyond the now-known curium (element number 96).
The rare earths metals or elements typically include scandium (Sc-21), yttrium (Y-39) and the lanthanides - lanthanum (La-57), cerium (Ce-58), praseodymium (Pr-59), neodymium (Nd-60), promethium (Pm-61), samarium (Sm-62), europium (Eu-63), gadolinium (Gd-64), terbium (Tb-65), dysprosium (Dy-66), holmium (Ho-67), erbium (Er-68), thulium (Tm-69), ytterbium (Yb-70), and lutetium (Lu-71).
All the REEs except promethium are more abundant than silver or mercury.
Less well-known is the promethium, atomic number 61, in the paint on an old compass.
Accompanying the other changes, FG Sagittae's spectrum exhibited increasing amounts of barium, zirconium, yttrium, and several "rare earths," including such underappreciated elements as cerium, praseodymium, neodymium, promethium, samarium, and gadolinium.
O'Neill explains that promethium inherently responds to changes in thickness with more sensitivity, making it more appropriate on thin films.