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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
    Polonium, a radioactive, silvery-gray or black metallic element of the oxygen group (Group 16 [VIa] in the periodic table) 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
    What is polonium (element 84), is it a metal or metalloid, electron configuration, family, isotopes, half-life, common uses, how much is it worth
  • Polonium: Element Properties, Uses, History, and Safety
    Polonium is a rare radioactive element with distinct chemical and physical properties This post clearly details its common uses and preparation methods
  • Polonium Element Facts - chemicool. com
    Polonium was the first element discovered by Marie and Pierre Curie They discovered polonium and then radium in 1898 in Paris, while investigating radioactivity in pitchblende (uranium oxide) They wrote: “We believe the substance we have extracted from pitchblende contains a metal never known before, similar to bismuth in its analytic
  • Polonium Facts - Po or Atomic Number 84 - Science Notes and Projects
    Learn about polonium Get element facts about Po or atomic number 84, including its discovery, uses, sources, and hazards
  • Polonium on the 125th anniversary of its discovery: its chemistry . . .
    Polonium is historically the first among the radioactive elements and has been the subject of numerous studies by Polish scientists It continues to deserve special attention due to its “mysterious” properties The discovery of polonium and the analytical methods used to extract it from pitchblende were described by the discoverer herself
  • Periodic Table of Elements: Los Alamos National Laboratory
    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 The electroscope showed it separating with bismuth Sources Polonium is a very rare natural element Uranium ores contain only about 100 micrograms of the element per ton
  • Polonium | Po (Element) - PubChem
    Chemical element, Polonium, information from authoritative sources Look up properties, history, uses, and more





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