147 (number) — 147 is the natural number following 146 and preceding 148.In mathematicsThere are 147 one sided 6 polyhexes.The digits forming 147 also form the left hand column of a normal decimal numeric keypad.The binary form of 147 is one of the binary… … Wikipedia
Promethium — Eigenschaften … Deutsch Wikipedia
promethium — /preuh mee thee euhm/, n. Chem. a rare earth, metallic, trivalent element. Symbol: Pm; at. no.: 61. [1945 50; < NL; see PROMETHEUS, IUM] * * * ▪ chemical element (Pm), chemical element, only rare earth metal of transition Group IIIb of the… … Universalium
Promethium — (pronEng|prəˈmiːθiəm/, /proʊˈmiːθiəm) is a chemical element with the symbol Pm and atomic number 61. It is notable for being the only other exclusively radioactive element besides technetium which is followed by chemical elements that have stable … Wikipedia
promethium — Symbol: Pm Atomic number: 61 Atomic weight: (147) Soft silvery metallic element, belongs to the lanthanoids. Pm 147, the only natural isotope, is radioactive and has a half life of 252 years. Eighteen radioisotopes have been produced, but all… … Elements of periodic system
promethium — 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] * * * pro·me·thi·um prə mē… … Medical dictionary
rare-earth element — /rair errth /, Chem. any of a group of closely related metallic elements, comprising the lanthanides, scandium, and yttrium, that are chemically similar by virtue of having the same number of valence electrons. Also called rare earth metal. [1955 … Universalium
Nuclear fission product — Nuclear fission products are the atomic fragments left after a large atomic nucleus fissions. Typically, a large nucleus like that of uranium fissions by splitting into two smaller nuclei, along with a few neutrons and a large release of energy… … Wikipedia
Оксид прометия(III) — Общие Систематическое наименование Оксид прометия(III) Традиционные названия Сесквиоксид прометия Химическая формула Pm2O3 Физические свойства … Википедия
Radioisotope thermoelectric generator — A radioisotope thermoelectric generator (RTG, RITEG) is an electrical generator which obtains its power from radioactive decay. In such a device, the heat released by the decay of a suitable radioactive material is converted into electricity by… … Wikipedia
