Silica

Silica
The chief component of sand and a substance responsible for lung disease and cancer. Crystalline silica of respirable size is primarily quartz dust occurring in industrial and occupational settings in the form of fine, breathable particles. Respirable crystalline silica results from mining and grinding coal. In the year 2000, crystalline silica of respirable size was upgraded by the U.S. government to a "known human carcinogen." There are increased lung cancer rates in workers exposed to respirable-size (breathable) crystalline silica, primarily quartz and crystabolite, that are generated during sandblasting and similar activities in an occupational setting.
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The chief constituent of sand, hence of glass. SYN: silicic anhydride, silicon dioxide. [Mod. L. fr. L. silex (silic-), flint]
- s. gel a precipitated form of silicic acid, used for adsorption of various gases.

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sil·i·ca 'sil-i-kə n the dioxide of silicon SiO2 that is used as an ingredient of simethicone and that occurs naturally in crystalline, amorphous, and impure forms (as in quartz, opal, and sand respectively) called also silicon dioxide

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sil·i·ca (silґĭ-kə) [L. silex flint] SiO2, silicon dioxide or silicic anhydride, occurring in nature as agate, sand, amethyst, chalcedony, cristobalite, flint, quartz, and tridymite. It is one of the major constituents of dental porcelain and a common filler in resin composites; in granular form it serves as a dental abrasive and polishing agent. See also silicosis.

Medical dictionary. 2011.

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Look at other dictionaries:

  • Silica — (Village) Administration Pays …   Wikipédia en Français

  • silică — SILÍCĂ, silice, s.f. Material refractar compus mai ales din bioxid de siliciu; cărămidă refractară silicioasă. – Din silice. Trimis de LauraGellner, 13.09.2007. Sursa: DEX 98  SILÍCĂ s. (constr.) dinas. (silică este o cărămidă refractară… …   Dicționar Român

  • Silica — Sil i*ca, n. [NL., from L. silex, silics, a flint.] (Chem.) Silicon dioxide, SiO?. It constitutes ordinary quartz (also opal and tridymite), and is artifically prepared as a very fine, white, tasteless, inodorous powder. [1913 Webster] …   The Collaborative International Dictionary of English

  • şilica — şílica! interj. (reg.; repetat) cuvânt cu care se cheamă raţele; mani!, uti!. Trimis de blaurb, 08.02.2007. Sursa: DAR …   Dicționar Român

  • silica — hard silicon dioxide, 1801, Modern Latin, from L. silex (gen. silicis) flint, pebble, on model of alumina, soda …   Etymology dictionary

  • sílica — s. f. 1. Substância branca e sólida chamada também óxido de silício. 2. Síliqua …   Dicionário da Língua Portuguesa

  • šilica — šȉlica ž DEFINICIJA lokal., v. krojačica ETIMOLOGIJA vidi šiti …   Hrvatski jezični portal

  • silica — ► NOUN ▪ silicon dioxide, a hard, unreactive, colourless compound which occurs as quartz and in sandstone and many other rocks. DERIVATIVES siliceous adjective. ORIGIN from Latin silex flint , on the pattern of words such as alumina …   English terms dictionary

  • silica — [sil′i kə] n. [ModL < L silex, flint: see SILEX] a glassy, very hard mineral, silicon dioxide, SiO2, found in a variety of forms, as in quartz, opal, chalcedony, sand, or chert …   English World dictionary

  • silica — /sil i keuh/, n. the dioxide form of silicon, SiO2, occurring esp. as quartz sand, flint, and agate: used usually in the form of its prepared white powder chiefly in the manufacture of glass, water glass, ceramics, and abrasives. Also called… …   Universalium

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