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Bessemer process

(Encyclopedia)CE5 Bessemer converter Bessemer process bĕsˈəmər [key] [for Sir Henry Bessemer], industrial process for the manufacture of steel from molten pig iron. The principle involved is that of oxidati...

combustion

(Encyclopedia)combustion, rapid chemical reaction of two or more substances with a characteristic liberation of heat and light; it is commonly called burning. The burning of a fuel (e.g., wood, coal, oil, or natura...

emphysema

(Encyclopedia)emphysema ĕmfĭsēˈmə [key], pathological or physiological enlargement or overdistention of the air sacs of the lungs. A major cause of pulmonary insufficiency in chronic cigarette smokers, emphyse...

gas, fuel

(Encyclopedia)gas, fuel, gaseous substance that burns in air and releases enough heat to be useful as a fuel, while also remaining sufficiently stable at ordinary temperatures to permit long-term storage without de...

vortex

(Encyclopedia)vortex vôrˈtĕks [key], mass of fluid in whirling or rotary motion. To simplify the analysis, vortex motion usually describes motions in a frictionless fluid. In such cases the absence of friction w...

reed instrument

(Encyclopedia)reed instrument, in music, an instrument whose sound-producing agent is a thin strip of cane, wood, plastic, or metal that vibrates as air is passed over it. The predecessor of these instruments is th...

Delaware, river, United States

(Encyclopedia)Delaware dĕlˈəwâr, –wər [key], river, c.280 mi (450 km) long, rising in the Catskill Mts., SE N.Y., in east and west branches, which meet at Hancock. It flows SE along the New York–Pennsylvan...

eutrophication

(Encyclopedia)eutrophication yo͞otrōˌfĭkāˈshən [key], aging of a lake by biological enrichment of its water. In a young lake the water is cold and clear, supporting little life. With time, streams draining i...

hydrology

(Encyclopedia)hydrology, study of water and its properties, including its distribution and movement in and through the land areas of the earth. The hydrologic cycle consists of the passage of water from the oceans ...

Lloyd's

(Encyclopedia)Lloyd's, London insurance underwriting corporation of many separate syndicates; often called Lloyd's of London. Founded in the late 17th cent. by a group of merchants, shipowners, and insurance broker...