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meprobamate

(Encyclopedia)meprobamate məprōˈbəmātˌ [key], tranquilizing drug that acts as a depressant of the central nervous system and is commonly used in the treatment of anxiety and sometimes schizophrenia. Although ...

geochemistry

(Encyclopedia)geochemistry, study of the chemical changes on the earth. More specifically, it is the study of the absolute and relative abundances of chemical elements in the minerals, soils, ores, rocks, water, an...

Dasht-e Kavir

(Encyclopedia)Dasht-e Kavir däsht-ēkävērˈ [key], great salt desert, c.500 mi (800 km) long and c.200 mi (320 km) wide, SE of the Elburz Mts., N central Iran. It is a huge basin of interior drainage named after...

radiochemistry

(Encyclopedia)radiochemistry, chemistry of radioactive substances (see radioactivity). Radioactive isotopes are very useful as tracers to study the mechanisms of complex organic reactions, since even minute amounts...

gasohol

(Encyclopedia)gasohol, a gasoline extender made from a mixture of gasoline (90%) and ethanol (10%; often obtained by fermenting agricultural crops or crop wastes) or gasoline (97%) and methanol, or wood alcohol (3%...

Hassel, Odd

(Encyclopedia)Hassel, Odd ôd häsˈəl [key], 1897–1981, Norwegian chemist, b. Christiania (now Oslo), grad. Oslo Univ. (1920), Ph.D. Univ. of Berlin (1924). After pursuing X-ray crystallographic studies in Germ...

Suger

(Encyclopedia)Suger süzhĕrˈ [key], 1081–1151, French cleric and statesman, abbot of Saint-Denis from 1122, minister of kings Louis VI and Louis VII. Born into a peasant family and educated at the abbey of Sain...

adhesion and cohesion

(Encyclopedia)adhesion and cohesion, attractive forces between material bodies. A distinction is usually made between an adhesive force, which acts to hold two separate bodies together (or to stick one body to anot...

yarrow

(Encyclopedia)yarrow, a plant of the genus Achillea, perennial herbs of the family Asteraceae (aster family), native to north temperate regions. Several species are cultivated as ornamentals for their flat-topped c...

cellulose

(Encyclopedia)cellulose, chief constituent of the cell walls of plants. Chemically, it is a carbohydrate that is a high molecular weight polysaccharide. Raw cotton is composed of 91% pure cellulose; other important...