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Broglie, Maurice, duc de

(Encyclopedia)Broglie, Maurice, duc de, 1875–1960, French physicist; brother of Louis Victor, duc de Broglie. His contributions include notable work on X rays and in atomic physics, radioactivity, and electricity...

fallout

(Encyclopedia)fallout, minute particles of radioactive material produced by nuclear explosions (see atomic bomb; hydrogen bomb; Chernobyl) or by discharge from nuclear-power or atomic installations and scattered th...

transition elements

(Encyclopedia)transition elements or transition metals, in chemistry, group of elements characterized by the filling of an inner d electron orbital as atomic number increases. This includes the elements from titani...

multiplication

(Encyclopedia)multiplication, fundamental operation in arithmetic and algebra. Multiplication by a whole number can be interpreted as successive addition. For example, a number N multiplied by 3 is N + N + N. In ge...

heat

(Encyclopedia)heat, nonmechanical energy in transit, associated with differences in temperature between a system and its surroundings or between parts of the same system. The study of heat and its relationship ...

fission

(Encyclopedia)fission, in physics: see nuclear energy and nucleus; see also atomic bomb. ...

International Union of Pure and Applied Chemistry

(Encyclopedia)International Union of Pure and Applied Chemistry (IUPAC), an international organization est. 1919 to advance the chemical sciences and contribute to the application of chemistry to the service of hum...

proton

(Encyclopedia)proton, elementary particle having a single positive electrical charge and constituting the nucleus of the ordinary hydrogen atom. The positive charge of the nucleus of any atom is due to its protons....

radium

(Encyclopedia)radium rāˈdēəm [key] [Lat. radius=ray], radioactive metallic chemical element; symbol Ra; at. no. 88; mass number of most stable isotope 226; m.p. 700℃; b.p. 1,140℃; sp. gr. about 6.0; valence...

Mayweather, Floyd, Jr.

(Encyclopedia)Mayweather, Floyd, Jr., 1977–, American boxer, b. Grand Rapids, Mich., as Floyd Joy Sinclair. He began boxing at an early age, coached by his father, a welterweight boxer whose name he subsequently ...