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thyristor
(Encyclopedia)thyristor, semiconductor switch used chiefly in power-control applications. Also called a silicon-controlled rectifier (SCR; see rectifier), it is a variation of the transistor. A thyristor is capable...nonmetal
(Encyclopedia)nonmetal, chemical element possessing certain properties by which it is distinguished from a metal. In general, this distinction is drawn on the basis that a nonmetal tends to accept electrons and for...Wollaston, William Hyde
(Encyclopedia)Wollaston, William Hyde, 1766–1828, English scientist, M.D. Cambridge, 1793. His wide-ranging scientific achievements include the discovery (1802) of the dark lines (Fraunhofer lines) in the solar s...shape memory
(Encyclopedia)shape memory, property possessed by certain alloys that allows them to return, when heated, to their original shape after having been deformed. This effect results because, as the alloy is deformed, i...Santa Clara, city, United States
(Encyclopedia)Santa Clara sănˈtə klârˈə [key], city (1990 pop. 93,613), Santa Clara co., W Calif.; inc. 1852. Part of the Silicon Valley high-technology manufacturing complex, the city produces a variety of e...composite material
(Encyclopedia)composite material or composite, any material made from at least two discrete substances, such as concrete. Many materials are produced as composites, such as the fiberglass-reinforced plastics used f...Berzelius, Jöns Jakob, Baron
(Encyclopedia)Berzelius, Jöns Jakob, Baron bərzēˈlēəs; Swed. yöns yäˈkôp bĕrsāˈlĭəs [key], 1779–1848, Swedish chemist, M.D. Univ. of Uppsala, 1802. He was noted for his work as teacher at the medic...bauxite
(Encyclopedia)bauxite bôkˈsīt, bŏkˈ– [key], mixture of hydrated aluminum oxides usually containing oxides of iron and silicon in varying quantities. A noncrystalline substance formerly thought to be a minera...abrasive
(Encyclopedia)abrasive, material used to grind, smooth, cut, or polish another substance. Natural abrasives include sand, pumice, corundum, and ground quartz. Carborundum (silicon carbide) and alumina (aluminum oxi...grinding
(Encyclopedia)grinding, process by which surface material is removed from an object, usually metal, by the abrasive action of a rotating wheel or a moving belt that contains abrasive grains. A grinding wheel can be...Browse by Subject
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