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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...

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 ...

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...

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...

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...

Bakelite

(Encyclopedia)Bakelite bāˈkəlīt [key] [for its inventor, L. H. Baekeland], synthetic thermosetting resin. It has been widely used both alone, to form whole objects, and in combination with other materials, as a...

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...

vulcanization

(Encyclopedia)vulcanization vŭlˌkənəzāˈshən [key], treatment of rubber to give it certain qualities, e.g., strength, elasticity, and resistance to solvents, and to render it impervious to moderate heat and c...

Theodore of Mopsuestia

(Encyclopedia)Theodore of Mopsuestia mŏpˌsyo͞oĕsˈchə [key], c.350–428, Syrian Christian theologian, bishop of Mopsuestia (from 392). Together with his lifelong friend, St. John Chrysostom, he studied at the...