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cathode-ray tube

(Encyclopedia)CE5 Cathode-ray tube cathode-ray tube (CRT), special-purpose electron tube in which electrons are accelerated by high-voltage anodes, formed into a beam by focusing electrodes, and projected towar...

causality

(Encyclopedia)causality, in philosophy, the relationship between cause and effect. A distinction is often made between a cause that produces something new (e.g., a moth from a caterpillar) and one that produces a c...

purslane

(Encyclopedia)CE5 Purslane, Portulaca oleraceae purslane, common name for some plants of the Portulaceae, a family of herbs and a few small shrubs, chiefly of the Americas. The portulacas or purslanes (genus Po...

calculus

(Encyclopedia)CE5 The derivative f″(x) of the function f(x) at the point P represents the slope of the tangent line at that point. CE5 The area under the curve y=f(x) may be found by calculating the sum of ...

Coco

(Encyclopedia)Coco, river, c.466 mi (750 km) long, rising in S Honduras and flowing E into Nicaragua and then NE to the Caribbean Sea. Part of the Mosquito Coast region, and once the object of dispute between Hondu...

Vyazma

(Encyclopedia)Vyazma vyäzˈmə [key], city (1989 pop. 59,000), N central European Russia, on the Vyazma River, a tributary of the Dnieper. Founded in the 9th cent., Vyazma became an important trade and military ce...

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...

isomer

(Encyclopedia)isomer īˈsəmər [key], in chemistry, one of two or more compounds having the same molecular formula but different structures (arrangements of atoms in the molecule). Isomerism is the occurrence of ...

trigonometry

(Encyclopedia)trigonometry [Gr.,=measurement of triangles], a specialized area of geometry concerned with the properties of and relations among the parts of a triangle. Spherical trigonometry is concerned with the ...

Estrées, Gabrielle d'

(Encyclopedia)Estrées, Gabrielle d' gäbrēĕlˈ dĕstrāˈ [key], 1573–99, famous beauty, mistress (1592–99) of Henry IV of France, who made her marquise of Monceaux and duchess of Beaufort. She divorced her ...

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