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half-life
(Encyclopedia)half-life, measure of the average lifetime of a radioactive substance (see radioactivity) or an unstable subatomic particle. One half-life is the time required for one half of any given quantity of th...radioactive waste
(Encyclopedia)radioactive waste, material containing the unusable radioactive byproducts of the scientific, military, and industrial applications of nuclear energy. Since its radioactivity presents a serious health...radiochemistry
(Encyclopedia)radiochemistry, chemistry of radioactive substances (see radioactivity). Radioactive isotopes are very useful as tracers to study the mechanisms of complex organic reactions, since even minute amounts...Becquerel
(Encyclopedia)Becquerel bĕkərĕlˈ [key], family of French physicists. Antoine César Becquerel, 1788–1878, was a pioneer in electrochemical science. He was professor of physics at the Muséum d'Histoire nature...Joliot-Curie
(Encyclopedia)Joliot-Curie ērĕnˈ [key], 1897–1956, daughter of Pierre and Marie Curie, were married in 1926. Both were assistants at the Radium Institute in Paris, of which Irène, succeeding her mother, was d...Piccard, Auguste
(Encyclopedia)Piccard, Auguste ōgüstˈ pēkärˈ [key], 1884–1962, Swiss physicist, b. Basel. He became a professor at the Univ. of Brussels in 1922. He and his twin brother Jean Felix (d. 1963) are known for t...transmutation of elements
(Encyclopedia)transmutation of elements, conversion of one chemical element into another. The expression has both historical and contemporary significance. The transmutation of certain metals into gold by means of ...gamma radiation
(Encyclopedia)gamma radiation, high-energy photons emitted as one of the three types of radiation resulting from natural radioactivity. It is the most energetic form of electromagnetic radiation, with a very short ...polonium
(Encyclopedia)polonium pəlōˈnēəm [key], radioactive chemical element; symbol Po; at. no. 84; mass no. of most stable isotope 209; m.p. 254℃; b.p. 962℃; sp. gr. about 9.4; valence +2 or +4. Polonium is an e...parity
(Encyclopedia)parity or space parity, in physics, quantity that refers to the relationship between an object or process and the image that it can produce in a mirror. For example, any right-handed object will produ...Browse by Subject
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