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radiation sickness

(Encyclopedia)radiation sickness, harmful effect produced on body tissues by exposure to radioactive substances. The biological action of radiation is not fully understood, but it is believed that a disturbance in ...

defoliant

(Encyclopedia)defoliant, any one of several chemical compounds that, when applied to plants, can alter their metabolism, causing the leaves to drop off. In agriculture defoliants are used to eliminate the leaves of...

legion

(Encyclopedia)legion, large unit of the Roman army. It came into prominence c.400 b.c. It originally consisted of 3,000 to 4,000 men drawn into eight ranks: the first six ranks, called hoplites, were heavily armed,...

Celtic art

(Encyclopedia)Celtic art kĕlˈtĭk, sĕlˈ– [key]. The earliest clearly Celtic style in art was developed in S Germany and E France by tribal artisans of the mid- to late 5th cent. b.c. With the dispersal of Cel...

electron-volt

(Encyclopedia)electron-volt, abbr. eV, unit of energy used in atomic and nuclear physics; 1 electron-volt is the energy transferred in moving a unit charge, positive or negative and equal to that charge on the elec...

Clancy, Tom

(Encyclopedia)Clancy, Tom (Thomas Leo Clancy, Jr.), 1947–2013, American popular novelist, b. Baltimore, grad. Loyola Univ. Maryland (B.A., 1969). While working as an insurance agent he wrote The Hunt for Red Octo...

Cohen, Samuel Theodore

(Encyclopedia)Cohen, Samuel Theodore, 1921–2010, American physicist known as the “father of the neutron bomb,” b. Brooklyn, N.Y., grad. Univ. of California, Los Angeles, 1943. He worked on the Manhattan Proje...

Fuchs, Klaus Emil

(Encyclopedia)Fuchs, Klaus Emil fo͝oks, fo͞oks [key], 1912–88, British physicist and Communist spy, b. Germany. In 1933 he fled Germany for England, where he completed his education. Interned (1940–41) in Can...

Kahn, Herman

(Encyclopedia)Kahn, Herman kän [key], 1922–83, American military strategist. b. Bayonne, N.J. After graduate work in physics at the California Institute of Technology, he joined the Rand Corporation. Unlike scho...

Lop Nur

(Encyclopedia)Lop Nur lôp nûr [key], salt basin, SE Xinjiang Uygur Autonomous Region, China, in the Tarim River basin. Since 1964, Lop Nur has been used by the China for its nuclear test explosions. Once a large ...