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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
  • 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
    Polonium is a very rare natural element It is found in uranium ores but it is uneconomical to extract it It is obtained by bombarding bismuth-209 with neutrons to give bismuth-210, which then decays to form polonium
  • 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 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]
  • Isotopes of polonium - Wikipedia
    There are 42 known isotopes of polonium (84 Po), all radioactive, stretching from 186 Po to 227 Po The isotopes 210 through 218 occur naturally in the four principal decay chains; of these, 210 Po with a half-life of 138 376 days has the longest half-life and is, therefore, the most abundant by mass
  • Polonium | Po | CID 6328143 - PubChem
    It is a post-transition metal atom and a chalcogen A radioactive element that is a member of the chalcogen family It has the atomic symbol Po, atomic number 84, and the atomic weight of the isotope with the longest half-life (209Po) is 208 98 It decays by alpha-emission
  • 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
  • What Is Radium and Polonium? Their Properties and Dangers
    Polonium is a rare metalloid found near the dividing line between metals and nonmetals Its most significant isotope, Polonium-210, has a half-life of just 138 days, making it scarce and highly volatile
  • Polonium Polonium-K | Otter Creek Labs
    The Polonium uses a 6mm bore that is also compatible with any 6mm 243 cartridges and has a highly effective built in internal and external flash hider that offers superior flash reduction over the competition when using night vision or when shooting in low light conditions





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