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hydrate

(Encyclopedia)hydrate hīˈdrāt [key], chemical compound that contains water. A common hydrate is the familiar blue vitriol, a crystalline form of cupric sulfate. Chemically, it is cupric sulfate pentahydrate, CuS...

Challenger expedition

(Encyclopedia)Challenger expedition, British oceanographic expedition under the direction of the Scottish professor Charles Wyville Thompson and the British naturalist Sir John Murray. Taking place from 1872 to 187...

Smith, W. Eugene

(Encyclopedia)Smith, W. Eugene (William Eugene Smith), 1918–78, American photojournalist, b. Wichita, Kan. Smith is considered one of the principal masters of modern photojournalism. The distorted newspaper cover...

Ramakrishnan, Venkatraman

(Encyclopedia)Ramakrishnan, Venkatraman, 1952–, American molecular biologist, b. India, Ph.D. Ohio Univ., 1976. He was a researcher at Oak Ridge National Laboratory (1982–83) and at Brookhaven National Laborato...

Paracelsus, Philippus Aureolus

(Encyclopedia)Paracelsus, Philippus Aureolus fĭlĭpˈəs ôrēōˈləs părəsĕlˈsəs [key], 1493?–1541, Swiss physician and alchemist. His original name Theophrastus Bombastus von Hohenheim. He traveled widel...

Axelrod, Julius

(Encyclopedia)Axelrod, Julius ăkˈsəlrŏd [key], 1912–2004, American biochemist whose work was influential in the development of pharmaceuticals, b. New York City, grad. City College, N.Y. (B.S. 1933), New York...

wax

(Encyclopedia)wax, substance secreted by glands on the abdomen of the bee and known commonly as beeswax; also various substances resembling beeswax. Waxes are mixtures comprising chiefly esters of monohydroxy alcoh...

micromechanics

(Encyclopedia)micromechanics, the combination of minuscule electrical and mechanical components in a single device less than 1 mm across, such as a valve or a motor. Although micromechanical production processes an...

mixture

(Encyclopedia)mixture, in chemistry, a physical combination of two or more pure substances (i.e., elements or compounds). A mixture is distinguished from a compound, which is formed by the chemical combination of t...

electroconvulsive therapy

(Encyclopedia)electroconvulsive therapy in psychiatry, treatment of mood disorders by means of electricity; the broader term “shock therapy” also includes the use of chemical agents. The therapeutic possibiliti...