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fuel cell

(Encyclopedia)fuel cell, electric cell in which the chemical energy from the oxidation of a gas fuel is converted directly to electrical energy in a continuous process (see oxidation and reduction). The efficiency ...

gallium

(Encyclopedia)gallium gălˈēəm [key], metallic chemical element; symbol Ga; at. no. 31; at. wt. 69.723; m.p. 29.78℃; b.p. 2,403℃; sp. gr. 5.904 at 29.6℃ (solid), 6.095 at 29.8℃ (liquid); valence +2 or +3...

octane number

(Encyclopedia)octane number, figure of merit representing the resistance of gasoline to premature detonation when exposed to heat and pressure in the combustion chamber of an internal-combustion engine. Such detona...

Manipur

(Encyclopedia)Manipur mənĭpo͝orˈ [key], state (2001 provisional pop. 2,388,634), 8,628 sq mi (22,347 sq km), NE India, bordered by Myanmar on the south and east. Imphal is the capital. The terrain, mostly jungl...

aspirin

(Encyclopedia)aspirin, acetyl derivative of salicylic acid (see salicylate) that is used to lower fever, relieve pain, reduce inflammation, and thin the blood. Common conditions treated with aspirin include headach...

Pascal, Blaise

(Encyclopedia)Pascal, Blaise blĕz päskälˈ [key], 1623–62, French scientist and religious philosopher. Studying under the direction of his father, a civil servant, Pascal showed great precocity, especially in ...

Roe v. Wade

(Encyclopedia)Roe v. Wade, case decided in 1973 by the U.S. Supreme Court. Along with Doe v. Bolton, this decision legalized abortion in the first trimester of ...

xenon

(Encyclopedia)xenon zēˈnŏn [key] [Gr.,=strange], gaseous chemical element; symbol Xe; at. no. 54; at. wt. 131.293; m.p. −111.9℃; b.p. −107.1℃; density 5.86 grams per liter at STP; valence usually 0. Xeno...

Wright brothers

(Encyclopedia)Wright brothers, American airplane inventors and aviation pioneers. Orville Wright 1871–1948, was born in Dayton, Ohio, and Wilbur Wright, 1867–1912, near New Castle, Ind. Their interest in aviati...

white dwarf

(Encyclopedia)white dwarf, in astronomy, a type of star that is abnormally faint for its white-hot temperature (see mass-luminosity relation). Typically, a white dwarf star has the mass of the sun and the radius of...