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National Security Agency

(Encyclopedia)National Security Agency (NSA), an independent agency within the U.S. Dept. of Defense. Founded by presidential order in 1952, its primary functions are to collect and analyze communications intellige...

Central Intelligence Agency

(Encyclopedia)Central Intelligence Agency (CIA), independent executive bureau of the U.S. government established by the National Security Act of 1947, replacing the wartime Office of Strategic Services (1942–45),...

gram-atomic weight

(Encyclopedia)gram-atomic weight, amount of an atomic substance whose weight, in grams, is numerically equal to the atomic weight of that substance. For example, 1 gram-atomic weight of atomic oxygen, O (atomic wei...

atomic force microscope

(Encyclopedia)atomic force microscope (AFM), device that uses a spring-mounted probe to image individual atoms on the surface of a material, first developed by Gerd Binnig in 1986. Unlike the scanning tunneling mic...

atomic mass unit

(Encyclopedia)atomic mass unit or amu, in chemistry and physics, unit defined as exactly 1⁄12 the mass of an atom of carbon-12, the isotope of carbon with six protons and six neutrons in its nucleus. One amu is e...

Cockcroft, Sir John Douglas

(Encyclopedia)Cockcroft, Sir John Douglas, 1897–1967, English physicist, educated at the Univ. of Manchester and St. John's College, Cambridge. He was a fellow of St. John's College (1928–46) and professor of n...

Nansen International Office for Refugees

(Encyclopedia)Nansen International Office for Refugees, worldwide agency est. 1931 by the League of Nations to work on behalf of refugees. It was named for Fridjof Nansen, head of the League's High Commission for R...

Evatt, Herbert Vere

(Encyclopedia)Evatt, Herbert Vere vĭr ĕvˈət [key], 1894–1965, Australian statesman. He became (1940) a Labor member of the House of Representatives, before being appointed (1941) attorney general and then min...

Oak Ridge

(Encyclopedia)Oak Ridge, city (1990 pop. 27,310), Anderson and Roane counties, E Tenn., on Black Oak Ridge and the Clinch River; founded by the U.S. government 1942, inc. as an independent city 1959. For years Oak ...

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