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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...

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...

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...

Seaborg, Glenn Theodore

(Encyclopedia)Seaborg, Glenn Theodore sēˈbôrg [key], 1912–99, American chemist, b. Ishpeming, Mich., grad. Univ. of California at Los Angeles, 1934, Ph.D. Univ. of California at Berkeley, 1937. In 1939, he beg...

Interstate Commerce Commission

(Encyclopedia)Interstate Commerce Commission (ICC), former independent agency of the U.S. government, established in 1887; it was charged with regulating the economics and services of specified carriers engaged in ...

Federal Communications Commission

(Encyclopedia)Federal Communications Commission (FCC), independent executive agency of the U.S. government established in 1934 to regulate interstate and foreign communications in the public interest. The FCC is co...

Federal Trade Commission

(Encyclopedia)Federal Trade Commission (FTC), independent agency of the U.S. government established in 1915 and charged with keeping American business competition free and fair. The FTC has no jurisdiction over ban...