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Atomic Energy Commission
(Encyclopedia)Atomic Energy Commission (AEC), former U.S. government commission created by the Atomic Energy Act of 1946 and charged with the development and control of the U.S. atomic energy program following Worl...atomic mass
(Encyclopedia)atomic mass, the mass of a single atom, usually expressed in atomic mass units (amu). Most of the mass of an atom is concentrated in the protons and neutrons contained in the nucleus. Each proton or n...atomic number
(Encyclopedia)atomic number, often represented by the symbol Z, the number of protons in the nucleus of an atom, as well as the number of electrons in the neutral atom. Atoms with the same atomic number make up a c...atomic bomb
(Encyclopedia)atomic bomb or A-bomb, weapon deriving its explosive force from the release of nuclear energy through the fission (splitting) of heavy atomic nuclei. The first atomic bomb was produced at the Los Alam...atomic clock
(Encyclopedia)atomic clock, electric or electronic timekeeping device that is controlled by atomic or molecular oscillations. A timekeeping device must contain or be connected to some apparatus that oscillates at a...atomic energy
(Encyclopedia)atomic energy: see nuclear energy. ...Richards, Theodore William
(Encyclopedia)Richards, Theodore William, 1868–1928, American chemist, b. Germantown, Pa., Ph.D. Harvard, 1888. Richards was a professor at Harvard from 1891 until his death in 1928. In 1914 he received the Nobel...Bhabha, Homi Jehangir
(Encyclopedia)Bhabha, Homi Jehangir jəhänˌgērˈ bäˈbä [key], 1909–66, Indian physicist, b. Bombay (now Mumbai). He was educated at the Royal Institute of Science, Bombay, and at Cambridge, England, where h...Meyer, Julius Lothar
(Encyclopedia)Meyer, Julius Lothar, 1830–95, German chemist. He taught at Breslau, Karlsruhe, and Tübingen (from 1876) and is known especially for his work in the development of the periodic law, for which, with...McMahon, Brien
(Encyclopedia)McMahon, Brien (James O'Brien McMahon), 1903–52, American statesman, b. Norwalk, Conn. After practicing law, he became a judge in Norwalk, and from 1933 to 1936 he served in the office of the U.S. A...Browse by Subject
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