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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...

ultrasonics

(Encyclopedia)ultrasonics, study and application of the energy of sound waves vibrating at frequencies greater than 20,000 cycles per second, i.e., beyond the range of human hearing. The application of sound energy...

reservoir

(Encyclopedia)reservoir rĕzˈəvôr, –vwär [key], storage tank or wholly or partly artificial lake for storing water. Building an embankment or dam to preserve a supply of water for irrigation is an ancient pra...

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...

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...

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...

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...

Sinclair, Upton

(Encyclopedia)Sinclair, Upton (Upton Beall Sinclair), 1878–1968, American novelist and socialist activist, b. Baltimore, grad. College of the City of New York, 1897. He was one of the muckrakers, and a dedication...

spinal cord

(Encyclopedia)spinal cord, the part of the nervous system occupying the hollow interior (vertebral canal) of the series of vertebrae that form the spinal column, technically known as the vertebral column. Extending...

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...