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kaolinite

(Encyclopedia)kaolinite kāˈəlĭnīt [key], clay mineral crystallizing in the monoclinic system and forming the chief constituent of china clay and kaolin. It is a hydrous aluminum silicate commonly formed by the...

Yost, Ed

(Encyclopedia)Yost, Ed (Paul Edward Yost), 1919–2007, American balloonist, b. Bristow, Iowa, grad. Boeing School of Aeronautics, 1940. The father of modern hot-air ballooning, Yost pioneered the used of propane (...

chemical reaction

(Encyclopedia)chemical reaction, process by which one or more substances may be transformed into one or more new substances. Energy is released or is absorbed, but no loss in total molecular weight occurs. When, fo...

Lindemann, Frederick Alexander

(Encyclopedia)Lindemann, Frederick Alexander (Viscount Cherwell) lĭnˈdəmən, chärˈwĕl [key], 1886–1957, British physicist and government official. He studied with W. H. Nernst and developed with him the Ner...

Lomonosov, Mikhail Vasilyevich

(Encyclopedia)Lomonosov, Mikhail Vasilyevich mēkhəyēlˈ vəsēˈlyəvĭch ləmənôˈsəf [key], 1711–65, Russian scientist, scholar, and writer, an outstanding figure in 18th-century Russia. Lomonosov was the...

thunder

(Encyclopedia)thunder, sound produced along a path of a lightning flash, caused by the rapid heating and expansion of the adjacent air; lightning can heat air to temperatures as much as five times hotter than those...

fire clay

(Encyclopedia)fire clay, clay that has a high degree of resistance to heat. By the best standards it should have a fusion point higher than 1,600℃. The term “fire clay” is commonly held to exclude kaolin and ...

firing

(Encyclopedia)firing, process of treating clay or other plastic ceramic materials with heat to produce a hard, durable but brittle material such as pottery. Primitive potters baked their clay in an open fire, but f...

turquoise

(Encyclopedia)turquoise, hydrous phosphate of aluminum and copper, Al2(OH)3PO4·H2O+Cu, used as a gem. It occurs rarely in crystal form, but is usually cryptocrystalline. Turquoise is opaque and has a waxy luster; ...

Tyndall, John

(Encyclopedia)Tyndall, John tĭnˈdəl [key], 1820–93, British physicist, b. Ireland. He became (1853) professor of natural philosophy at the Royal Institution and in 1867 succeeded Michael Faraday, his friend an...