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Meitner, Lise
(Encyclopedia)Meitner, Lise lēˈzə mītˈnər [key], 1878–1968, Austrian-Swedish physicist and mathematician. She was professor at the Univ. of Berlin (1926–33). A refugee from Germany after 1938, she became ...nuclear reactor
(Encyclopedia)CE5 Power reactor system nuclear reactor, device for producing controlled release of nuclear energy. Reactors can be used for research or for power production. A research reactor is designed to pr...uranium
(Encyclopedia)uranium yo͞orāˈnēəm [key], radioactive metallic chemical element; symbol U; at. no. 92; mass number of most stable isotope 238; m.p. 1,132℃; b.p. 3,818℃; sp. gr. 19.1 at 25℃; valence +3, +4...samarium
(Encyclopedia)samarium səmârˈēəm [key], metallic chemical element; symbol Sm; at. no. 62; at. wt. 150.36; m.p. 1,072℃; b.p. 1,791℃; sp. gr. 7.54 at 20℃; valence +2 or +3. Samarium is a lustrous silver-wh...iridium
(Encyclopedia)iridium ĭrĭdˈēəm [key], metallic chemical element; symbol Ir; at. no. 77; at. wt. 192.217; m.p. about 2,410℃; b.p. about 4,130℃; sp. gr. 22.55 at 20℃; valence +3 or +4. Iridium is a very ha...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 ...atomic weight
(Encyclopedia)atomic weight, mean (weighted average) of the masses of all the naturally occurring isotopes of a chemical element, as contrasted with atomic mass, which is the mass of any individual isotope. Althoug...hydrogen
(Encyclopedia)hydrogen hīˈdrəjən [key] [Gr.,=water forming], gaseous chemical element; symbol H; at. no. 1; interval in which at. wt. ranges 1.00784–1.00811; m.p. −259.14℃; b.p. −252.87℃; density 0.08...hydrogen bomb
(Encyclopedia)hydrogen bomb or H-bomb, weapon deriving a large portion of its energy from the nuclear fusion of hydrogen isotopes. In an atomic bomb, uranium or plutonium is split into lighter elements that togethe...cold fusion
(Encyclopedia)cold fusion or low-temperature fusion, nuclear fusion of deuterium, an isotope of hydrogen, at or relatively near room temperature. Fusion, the reaction involved in the release of the destructive ener...Browse by Subject
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