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sleep

(Encyclopedia)sleep, resting state in which an individual becomes relatively quiescent and relatively unaware of the environment. During sleep, which is in part a period of rest and relaxation, most physiological f...

metallurgy

(Encyclopedia)metallurgy mĕtˈəlûrˌjē [key], science and technology of metals and their alloys. Modern metallurgical research is concerned with the preparation of radioactive metals, with obtaining metals econ...

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...

Toulouse

(Encyclopedia)Toulouse to͞olo͞ozˈ [key], city (1990 pop. 365,933), capital of Haute-Garonne dept., S France, on the Garonne River. France's fastest growing region, it is one of France's great cultural and commer...

enthalpy

(Encyclopedia)enthalpy ĕnˈthălpē [key], measure of the heat content of a chemical or physical system; it is a quantity derived from the heat and work relations studied in thermodynamics. As a system changes fro...

gills, in biology

(Encyclopedia)CE5 Gills of a fish: Side view (A) and ventral view (B) gills, external respiratory organs of most aquatic animals. In fishes the gills are located in gill chambers at the rear of the mouth (phary...

frost

(Encyclopedia)frost or hoarfrost, ice formed by the condensation of atmospheric water vapor on a surface when the temperature of the surface is below 32℉ (0℃). In the formation of frost, a gas (water vapor) is ...

Kaufman, George S.

(Encyclopedia)Kaufman, George S. kôfˈmən [key], 1889–1961, American dramatist and journalist, b. Pittsburgh as George Kaufman. As a drama critic for various New York newspapers he was influential in raising th...

artillery

(Encyclopedia)artillery, originally meant any large weaponry (including such ancient engines of war as catapults and battering rams) or war material, but later applied only to heavy firearms as opposed to small arm...

caisson

(Encyclopedia)caisson kāˈsən, –sŏn [key] [Fr.,=big box], in engineering, a chamber, usually of steel but sometimes of wood or reinforced concrete, used in the construction of foundations or piers in or near a...