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uranium
uranium , radioactive metallic chemical element; symbol U; at. no. 92; at. wt. 238.0289; m.p. 1,132°C; b.p. 3,818°C; sp. gr. 19.1 at 25°C; valence +3, +4, +5, or +6.
Properties
Uranium is a hard, dense, malleable, ductile, silver-white, radioactive metal of the actinide series...
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Nicolas Léonard Sadi Carnot
Nicolas Léonard Sadi Carnot , 1796-1832, French physicist, a founder of modern thermodynamics; son of Lazare N. M. Carnot. His famous work on the motive power of heat ( Réflexions sur la puissance motrice du feu, 1824) is concerned with the relation between heat and mechanical energy....
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nucleosynthesis
nucleosynthesis or nucleogenesis, in astronomy, production of all the chemical elements from the simplest element, hydrogen, by thermonuclear reactions within stars, supernovas, and in the big bang at the beginning of the universe (see nucleus ; nuclear energy ). A star obtains its energy b...
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Iran
Iran , officially Islamic Republic of Iran, republic (2005 est. pop. 68,018,000), 636,290 sq mi (1,648,000 sq km), SW Asia. The country's name was changed from Persia to Iran in 1935. Iran is bordered on the north by Armenia, Azerbaijan, Turkmenistan, and the Caspian Sea; on the east by Afghanistan ...
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kinetic energy
kinetic energy The energy possessed by a body by virtue of its motion in space. It is equivalent to the work that would be done if the moving body were brought to rest. When the speed of a body is much less than the speed of light, kinetic energy is equal to ½mv2, where m is the mass of the bod...
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Three Mile Island
Three Mile Island site of a nuclear power plant 10 mi (16 km) south of Harrisburg, Pa. On Mar. 28, 1979, failure of the cooling system of the No. 2 nuclear reactor led to overheating and partial melting of its uranium core and production of hydrogen gas, which raised fears of an explosion and dis...
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energy
energy in physics, the ability or capacity to do work or to produce change. Forms of energy include heat , light , sound , electricity , and chemical energy. Energy and work are measured in the same units—foot-pounds, joules, ergs, or some other, depending on the system of measurement bei...
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United States Military Academy
United States Military Academy at West Point , N.Y.; for training young men and women to be officers in the U.S. army; founded and opened in 1802. The original act provided that the Corps of Engineers stationed at West Point should constitute a military academy, but the growing threat of war with ...
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polonium
polonium , radioactive chemical element; symbol Po; at. no. 84; mass no. of most stable isotope 209; m.p. 254°C; b.p. 962°C; sp. gr. about 9.4; valence +2 or +4. Polonium is an extremely rare element found in uranium ores (about 0.1 gram per ton). A product of radium decay, it is sometimes c...
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thermodynamics
thermodynamics branch of science concerned with the nature of heat and its conversion to mechanical, electric, and chemical energy . Historically, it grew out of efforts to construct more efficient heat engines—devices for extracting useful work from expanding hot gases.
The Thermody...
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