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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 radioactive element that exists in two metallic allotropes The alpha form is the only known example of a simple cubic crystal structure in a single atom basis at STP (space group Pm 3 m, no 221) The unit cell has an edge length of 335 2 picometers; the beta form is rhombohedral
  • Polonium | Definition, Symbol, Properties, Uses, Facts | Britannica
    polonium (Po), 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, a uranium ore
  • What is polonium, and how deadly is it? - NBC News
    Polonium-210 is one of the world's rarest elements, discovered in 1898 by scientists Marie and Pierre Curie and named in honor of her country of origin, Poland It occurs naturally
  • Is Polonium Harmful to Humans? Poisoning Symptoms - MedicineNet
    Polonium has about 25 known radioactive isotopes One of the most common and well-known polonium isotopes is polonium-210, which emits highly radioactive, positively charged particles called alpha particles Once a victim has polonium-210 poisoning, the effects are likely to be fatal
  • Polonium Facts, Symbol, Discovery, Uses, Poisoning - Chemistry Learner
    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 - 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 – 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
  • Facts About Polonium | Live Science
    Polonium (Po) is a very rare and highly volatile radioactive metal Before Polish-French physicist Marie Curie 's discovery of polonium in 1898, uranium and thorium were the only known
  • Polonium (Po) Element: Important Properties, Uses, Hazards - Science Info
    Polonium is a chemical element with an atomic number of 84 and is represented by the symbol ‘Po’ in the periodic table It is silvery in appearance and belongs to the p-block of group 16 of the periodic table Polonium is the heaviest element within the chalcogen family
  • Polonium Facts - Elements Are Interesting - ThoughtCo
    Polonium is a radioactive element that occurs naturally in the environment at very low levels or can be produced in a nuclear reactor Polonium-210 emits alpha particles, which can damage or destroy genetic material inside of cells





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