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polonium    音標拼音: [pəl'oniəm]
n. 釙

釙

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
  • 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
  • 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
  • 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 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 Element Facts - chemicool. com
    Polonium is a rare, silvery-gray, radioactive, low-melting metalloid Polonium readily reacts with dilute acids, but only slightly with alkalis All of its isotopes are radioactive
  • Polonium (Po) – Definition, Preparation, Properties, Uses . . . - Examples
    Polonium is a rare and highly radioactive element with the symbol Po and atomic number 84 Discovered by Marie Curie and named after her native Poland, polonium is unique due to its intense radioactivity It’s found in trace amounts in uranium ores and is produced synthetically in nuclear reactors





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