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polonium    音标拼音: [pəl'oniəm]
n. 钋



polonium
n 1: a radioactive metallic element that is similar to tellurium
and bismuth; occurs in uranium ores but can be produced by
bombarding bismuth with neutrons in a nuclear reactor [synonym:
{polonium}, {Po}, {atomic number 84}]

Polonium \Po*lo"ni*um\ (p[-o]*l[=o]"n[i^]*[u^]m), n. [NL. So
named after Poland, in L. form Polonia, one of the
discoverers being a Pole.] (Chem.)
A radioactive chemical element, discovered by M. and MMe.
Curie in pitchblende, and originally called {radium F}. It
has atomic number 84 and an atomic weight of 210. It is a
very rare natural element, having an abundance in uranium
ores only 0.2% that of radium. It is closely related
chemically to bismuth. It emits only alpha rays, and has a
half-life of 138 days. It is thus more unstable than radium,
and a milligram of polonium emits as many alpha particles as
5 grams of radium. Twenty-seven isotopes are known, with
atomic masses from 192 to 218. At present a more practical
method of preparation than isolation from ores is the
preparation by neutron bombardment of bismuth in a nuclear
reactor, and it may be obtained commercially by users having
an appropriate permit. --[HBCF61]
[Webster 1913 Suppl. PJC]



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  • Polonium - Wikipedia
    Polonium is a chemical element; it has symbol Po and atomic number 84 A rare and highly radioactive metal (although sometimes classified as a metalloid) with no stable isotopes, polonium is a chalcogen and chemically similar to selenium and tellurium, though its metallic character resembles that of its horizontal neighbours in the periodic table: thallium, lead, and bismuth Due to the short
  • Polonium | Definition, Symbol, Properties, Uses, Facts - Britannica
    The first element to be discovered by radiochemical analysis, polonium was discovered in 1898 by Pierre and Marie Curie, who were investigating the radioactivity of a certain pitchblende
  • Polonium - Element information, properties and uses | Periodic Table
    Element Polonium (Po), Group 16, Atomic Number 84, p-block, Mass [209] Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images
  • Polonium Facts, Symbol, Discovery, Uses, Poisoning
    Polonium (pronunciation: peh-LOW-nee-em) [3] is a rare, highly radioactive metalloid, classified as a Chalcogen [5] and represented by the chemical symbol Po [1, 2]
  • Polonium Facts - Po or Atomic Number 84 - Science Notes and Projects
    Polonium is a rare and highly radioactive element with the symbol Po and atomic number 84 A metal or metalloid in the periodic table, it lies in the p-block, and is a member of group 16, the chalcogens Its discovery in 1898 marked a significant milestone in the study of radioactivity
  • Polonium: Element Properties, Uses, History, and Safety
    Polonium is a rare and highly radioactive element Applications include thermoelectric power generation, the removal of static electricity, and biomedical research
  • Polonium (Po) | History | Research Starters - EBSCO
    Polonium (Po) is a rare, highly radioactive element classified under the chalcogen family, which includes oxygen and sulfur Discovered in 1898 by physicists Marie and Pierre Curie while studying pitchblende, polonium was named to honor Poland, a nod to Marie's heritage amidst its lack of independence at the time Known for having the most isotopes of any element, polonium-210 is the most
  • WebElements Periodic Table » Polonium » the essentials
    Polonium has more isotopes than any other element, all of which are radioactive Polonium dissolves readily in dilute acids, but is only slightly soluble in alkalis
  • Chemical Elements. com - Polonium (Po)
    For more information about citing online sources, please visit the MLA's Website
  • Polonium | Po (Element) - PubChem
    Polonium, also called Radium F, was the first element discovered by Curie in 1898 while seeking the cause of radioactivity of pitchblend from Joachimsthal, Bohemia





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