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McLennan, Sir John Cunningham

(Encyclopedia)McLennan, Sir John Cunningham, 1867–1935, Canadian physicist, grad. Univ. of Toronto (B.A., 1892; Ph.D., 1900). He taught at the Univ. of Toronto from 1892 to 1932, was professor of physics from 190...

sintering

(Encyclopedia)sintering, process of forming objects from a metal powder by heating the powder at a temperature below its melting point. In the production of small metal objects it is often not practical to cast the...

specific gravity

(Encyclopedia)specific gravity, ratio of the weight of a given volume of a substance to the weight of an equal volume of some reference substance, or, equivalently, the ratio of the masses of equal volumes of the t...

ferric sulfate

(Encyclopedia)ferric sulfate or iron (III) sulfate, chemical compound, Fe2(SO4)3, a yellow rhombic crystalline hygroscopic water-soluble salt that decomposes when heated to a temperature of 480℃. The enneahydrate...

freezing

(Encyclopedia)freezing, change of a substance from the liquid to the solid state. The temperature at which freezing occurs for a pure crystalline solid is called the freezing point and is a characteristic of the pa...

Sanctorius

(Encyclopedia)Sanctorius săngktôrˈēəs [key], Ital. Santorio, 1561–1636, Italian physiologist. He was a professor at Padua (1611–24). By his quantitative experiments in temperature, respiration, and weight,...

Verkhoyansk

(Encyclopedia)Verkhoyansk vyĕrkhəyänskˈ [key], town, Sakha Republic, NE Siberian Russia, on the Yana River, near the Arctic Circle. A river port, a fur-collecting depot, and the center of a reindeer-raising are...

Eris, in astronomy

(Encyclopedia)Eris, in astronomy, the largest known dwarf planet. Eris, whose highly eccentric elliptical orbit ranges from 38 AU to 97 AU and is inclined more than 44°, is the largest known object of the Kuiper b...

stratosphere

(Encyclopedia)stratosphere strătˈəsfēr [key], second lowest layer of the earth's atmosphere. The level from which it extends outward varies with latitude; it begins c.51⁄2 mi (9 km) above the poles, c.6 or 7 ...

solar wind

(Encyclopedia)solar wind, stream of ionized hydrogen—protons and electrons—with an 8% component of helium ions and trace amounts of heavier ions that radiates outward from the sun at high speeds. The continuous...