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petroleum

(Encyclopedia)petroleum, oily, flammable liquid that occurs naturally in deposits, usually beneath the surface of the earth; it is also called crude oil. It consists principally of a mixture of hydrocarbons, with t...

battery, electric

(Encyclopedia)CE5 Lead storage cell: At the lead-dioxide electrode, electrons from the circuit combine with lead dioxide and sulfuric acid to form lead sulfate and water. At the spongy-lead electrode, lead react...

iron

(Encyclopedia)iron, metallic chemical element; symbol Fe [Lat. ferrum]; at. no. 26; at. wt. 55.845; m.p. about 1,535℃; b.p. about 2,750℃; sp. gr. 7.87 at 20℃; valence +2, +3, +4, or +6. Iron is biologically s...

air pollution

(Encyclopedia)air pollution, contamination of the air by noxious gases and minute particles of solid and liquid matter (particulates) in concentrations that endanger health. The major sources of air pollution are t...

newspaper

(Encyclopedia)newspaper, publication issued periodically, usually daily or weekly, to convey information and opinion about current events. In England large newspaper-publishing empires were built up by Lords...

camera

(Encyclopedia)CE5 Image formed by a camera camera, lightproof box or container, usually fitted with a lens, which gathers incoming light and concentrates it so that it can be directed toward the film (in an opt...

Connecticut, state, United States

(Encyclopedia)CE5 Connecticut kənĕtˈĭkət [key], southernmost of the New England states of the NE United States. It is bordered by Massachusetts (N), Rhode Island (E), Long Island Sound (S), and New York (W)...

science

(Encyclopedia)science [Lat. scientia=knowledge]. For many the term science refers to the organized body of knowledge concerning the physical world, both animate and inanimate, but a proper definition would also hav...

computer

(Encyclopedia)CE5 Schematic diagram of a computer system: Data flow is indicated by solid lines; control signals are indicated by dashed lines. computer, device capable of performing a series of arithmetic or l...

space exploration

(Encyclopedia)CE5 Moon mission assembly CE5 Stages in a moon mission shown counterclockwise from launching on the first day to splashdown on the ninth day. space exploration, the investigation of physical co...

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