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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%...

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...

object-oriented programming

(Encyclopedia)object-oriented programming, a modular approach to computer program (software) design. Each module, or object, combines data and procedures (sequences of instructions) that act on the data; in traditi...

nitrous oxide

(Encyclopedia)nitrous oxide or nitrogen (I) oxide, chemical compound, N2O, a colorless gas with a sweetish taste and odor. Its density is 1.977 grams per liter at STP. It is soluble in water, alcohol, ether, and ot...

Autry, Gene

(Encyclopedia)Autry, Gene (Orvon Grover Autry), 1907–98, American entertainer and businessman, b. Tioga Springs, Tex. Probably the most successful of the movies' singing cowboys, Autry began singing o...

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...

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...

aerogel

(Encyclopedia)aerogel, any of a group of extremely light and porous solid materials; the lightest is less than four times as dense as dry air. Aerogels are produced from certain gels (see colloid) by heating the ge...