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smoke

(Encyclopedia)smoke, visible gaseous product of incomplete combustion. Smoke varies with its source, but it usually comprises hot gas and suspended particles of carbon and tarry substances, or soot. To reduce the a...

Hopkins

(Encyclopedia)Hopkins, city (2020 pop. 19,079), Hennepin co., SE Minn., a suburb of Minneapolis; inc. as West Minneapolis 1893, name changed 1928. The city manufactur...

Ichihara

(Encyclopedia)Ichihara ēchēˈhärä [key], city, Chiba prefecture, central Honshu, Japan, on Tokyo Bay. Part ...

temperature inversion

(Encyclopedia)temperature inversion, condition in which the temperature of the atmosphere increases with altitude in contrast to the normal decrease with altitude. When temperature inversion occurs, cold air underl...

aviation medicine

(Encyclopedia)aviation medicine, scientific study of the biological effects of aviation, especially on human beings. Although aviation medicine is concerned with such problems as the spread of diseases by persons t...

Earth Day

(Encyclopedia)Earth Day, Apr. 22, a day to celebrate the environment. The first Earth Day was organized in 1970 to promote the ideas of ecology, encourage respect for life on earth, and highlight growing concern ov...

toxic waste

(Encyclopedia)toxic waste is waste material, often in chemical form, that can cause death or injury to living creatures. It usually is the product of industry or commerce, but comes also from residential use, agric...

Environmental Protection Agency

(Encyclopedia)Environmental Protection Agency (EPA), independent agency of the U.S. government, with headquarters in Washington, D.C. It was established in 1970 to reduce and control air and water pollution, noise ...

solid waste

(Encyclopedia)solid waste, discarded materials other than fluids. In the United States in 1996, nearly 210 million tons—about 4.3 lb. (2 kg) per person daily (up from 2.7 lb./1.2 kg in 1960)—were collected and ...

basic oxygen process

(Encyclopedia)basic oxygen process, method of producing steel from a charge consisting mostly of pig iron. The charge is placed in a furnace similar to the one used in the Bessemer process of steelmaking except tha...