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recycling

(Encyclopedia)recycling, the process of recovering and reusing waste products—from household use, manufacturing, agriculture, and business—and thereby reducing their burden on the environment. During World War ...

sanitary science

(Encyclopedia)sanitary science, principles of health preservation, embracing hygiene, on an individual level, and public health, on a communal level. Those who specialize in sanitary science are sanitary engineers....

cloaca

(Encyclopedia)cloaca klōāˈkə [key], in biology, enlarged posterior end of the digestive tract of some animals. The cloaca, from the Latin word for sewer, is a single chamber into which pass solid and liquid was...

excretion

(Encyclopedia)excretion, process of eliminating from an organism waste products of metabolism and other materials that are of no use. It is an essential process in all forms of life. In one-celled organisms wastes ...

coke

(Encyclopedia)coke, substance obtained by the destructive distillation of bituminous coal. Coke bears the same relation to coal as does charcoal to wood. A hard, gray, massive, porous fuel, coke is the solid residu...

Sunita, Narain

(Encyclopedia)Sunita, Narain, 1961–, Indian writer and environmentalist, b. New Delhi, India, graduated from University of Delhi, honorary degrees from Cranfield ...

United Nations Conference on Environment and Development

(Encyclopedia)United Nations Conference on Environment and Development (UNCED) or Earth Summit, an 11-day meeting held in June, 1992, in Rio de Janeiro, Brazil, to discuss the global conflict between economic devel...

mining

(Encyclopedia)mining, extraction of solid mineral resources from the earth. These resources include ores, which contain commercially valuable amounts of metals, such as iron and aluminum; precious stones, such as d...

Yucca Mountain

(Encyclopedia)Yucca Mountain, mountain in the SW Nevada desert about 100 mi (161 km) northwest of Las Vegas. It is the proposed site of a Dept. of Energy (DOE) repository for up to 77,000 metric tons of nuclear was...

laxative

(Encyclopedia)laxative, drug or other substance used to stimulate the action of the intestines in eliminating waste from the body. The term laxative usually refers to a mild-acting substance; substances of increasi...