Columbia Encyclopedia

Search results

500 results found

tungsten

(Encyclopedia)tungsten tŭngˈstən [key] [Swed.,=heavy stone], metallic chemical element; symbol W; at. no. 74; at. wt. 183.84; m.p. about 3,410℃; b.p. 5,660℃; sp. gr. 19.3 at 20℃; valence +2, +3, +4, +5, or...

sediment

(Encyclopedia)sediment, mineral or organic particles that are deposited by the action of wind, water, or glacial ice. These sediments can eventually form sedimentary rocks (see rock). Sediments form sedimentary ...

atomic weight

(Encyclopedia)atomic weight, mean (weighted average) of the masses of all the naturally occurring isotopes of a chemical element, as contrasted with atomic mass, which is the mass of any individual isotope. Althoug...

paper

(Encyclopedia)paper, thin, flat sheet or tissue made usually from plant fiber but also from rags and other fibrous materials. It is used principally for printing and writing on but has many other applications. The ...

Defense Advanced Research Projects Agency

(Encyclopedia)Defense Advanced Research Projects Agency (DARPA), U.S. government agency administered by the Department of Defense (see Defense, United States Department of). It was established in 1958, in reaction ...

Holt, Joseph

(Encyclopedia)Holt, Joseph, 1807–94, American public official, judge advocate general of the U.S. army (1862–75), b. Breckinridge co., Ky. He became a widely known lawyer and political speaker in the old Southw...

Gardiner, Stephen

(Encyclopedia)Gardiner, Stephen, 1493?–1555, English prelate. He was educated at Cambridge. He became secretary to Thomas (later Cardinal) Wolsey and later secured the favor of Henry VIII by a mission to Rome to ...

Mullis, Kary Banks

(Encyclopedia)Mullis, Kary Banks, 1944–2019, American biochemist, b. Lenoir, N.C., Ph.D. Univ. of California, Berkeley, 1972. Mullis was a researcher with Cetus Corp., Emeryville, Calif., from 1979 to 1986 and wi...

myosin

(Encyclopedia)myosin mīˈəsĭn [key], one of the two major protein constituents responsible for contraction of muscle. In muscle cells myosin is arranged in long filaments called thick filaments that lie parallel...

Tallien, Jean Lambert

(Encyclopedia)Tallien, Jean Lambert zhäN läNbĕrˈ tälyăNˈ [key], 1767–1820, French revolutionary. A law clerk and later a printer, he became known through his Jacobin journal, Ami des citoyens. A leader in ...