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chain reaction

(Encyclopedia)CE5 Chain reaction: A neutron (n) strikes the uranium nucleus (U-235), causing it to split into fission products A and B and release two neutrons. These neutrons can in turn cause further fissions....

ephemeris

(Encyclopedia)ephemeris ĭfĕmˈərĭs [key] (pl., ephemerides), table listing the position of one or more celestial bodies for each day of the year. The French publication Connaissance de Temps is the oldest of th...

atmosphere

(Encyclopedia)CE5 Atmosphere atmosphere [Gr.,=sphere of air], the mixture of gases surrounding a celestial body with sufficient gravity to maintain it. Although some details about the atmospheres of other plane...

temperature inversion

(Encyclopedia)temperature inversion, condition in which the temperature of the atmosphere increases with altitude in contrast to the normal decrease with altitude. When temperature inversion occurs, cold air underl...

Whitefield, George

(Encyclopedia)Whitefield, George, 1714–70, English evangelistic preacher, leader of the Calvinistic Methodist Church. At Oxford, which he entered in 1732, he joined the Methodist group led by John Wesley and Char...

ventilation

(Encyclopedia)ventilation, process of supplying fresh air to an enclosed space and removing from it air contaminated by odors, gases, or smoke. Proper ventilation requires also that there be a movement or circulati...

Arnold, Henry Harley

(Encyclopedia)Arnold, Henry Harley, 1886–1950, American general, chief of the U.S. Army Air Forces (1942–46), known as “Hap” Arnold, B. Gladwyne, Pa., grad. West Point, 1907. Assigned (1911) to the aviation...

Langley, Samuel Pierpont

(Encyclopedia)Langley, Samuel Pierpont, 1834–1906, American scientist, b. Roxbury, Mass., received only a high school education but continued his studies in science in Boston libraries. He became, in 1866, profes...

Coningham, Sir Arthur

(Encyclopedia)Coningham, Sir Arthur kŭnˈĭng-əm [key], 1895–1948, British air marshal, b. Australia. During World War I, he served first in the New Zealand army and then joined (1916) the Royal Flying Corps, a...

Brown, Charles Quinton, Jr.

(Encyclopedia)Brown, Charles Quinton, Jr., 1962–, American air force general, b. San Antonio, Tex., B.S Texas Tech Univ., 1984, M.S. Embry-Riddle Aeronautical Univ., 1994. An ROTC graduate, he was commissioned as...