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osmosis

(Encyclopedia)osmosis ŏzmōˈsĭs [key], transfer of a liquid solvent through a semipermeable membrane that does not allow dissolved solids (solutes) to pass. Osmosis refers only to transfer of solvent; transfer o...

Wind Cave National Park

(Encyclopedia)Wind Cave National Park, 28,295 acres (11,459 hectares), in the Black Hills, SW S.Dak.; est. 1903. Wind Cave, discovered in 1881, was named for the strong air currents that blow alternately in and out...

Pfeffer, Wilhelm

(Encyclopedia)Pfeffer, Wilhelm vĭlˈhĕlm pfĕˈfər [key], 1845–1920, German plant physiologist. He was professor of botany successively at the universities of Bonn, Basel, Tübingen, and Leipzig (from 1887). W...

Onsager, Lars

(Encyclopedia)Onsager, Lars, 1903–76, American physical chemist, b. Oslo, Ph.D. Yale, 1935. Onsager taught at Brown Univ. from 1928 to 1933 and was on the faculty at Yale from 1933 until his retirement in 1972. H...

hydrogenation

(Encyclopedia)hydrogenation hīdrôjˈənāˌshən, hīˌdrəjənāˈshən [key], chemical reaction of a substance with molecular hydrogen, usually in the presence of a catalyst. A common hydrogenation is the harde...

bubble chamber

(Encyclopedia)bubble chamber, device for detecting charged particles and other radiation by means of tracks of bubbles left in a chamber filled with liquid hydrogen or other liquefied gas. It was invented in 1952 b...

Bergius, Friedrich Karl Rudolf

(Encyclopedia)Bergius, Friedrich Karl Rudolf, 1884–1949, German chemist, Ph.D. Univ. of Leipzig, 1907. In 1910, Bergius set up a laboratory to carry out his research and in 1914 transferred the operation to the E...

American Standard Code for Information Interchange

(Encyclopedia)American Standard Code for Information Interchange: see ASCII. ...

wind

(Encyclopedia)wind, flow of air relative to the earth's surface. A wind is named according to the point of the compass from which it blows, e.g., a wind blowing from the north is a north wind. The diurnal, or dai...

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...