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diode

(Encyclopedia)diode dīˈōd [key], two-terminal electronic device that permits current flow predominantly in only one direction. Most diodes are semiconductor devices; diode electron tubes are now used only for a ...

Pennsylvania Dutch

(Encyclopedia)Pennsylvania Dutch [Ger. Deutsch=German], people of E Pennsylvania of German descent who migrated to the area in the 18th cent., particularly those in Northampton, Berks, Lancaster, Lehigh, Lebanon, Y...

record player

(Encyclopedia)record player or phonograph, device for reproducing sound that has been recorded as a spiral, undulating groove on a disk. This disk is known as a phonograph record, or simply a record (see sound reco...

catfish

(Encyclopedia)catfish, common name applied to members of the fish families constituting the order Siluriformes, found in fresh and coastal waters. Catfish are named for the barbels (“whiskers”) around their mou...

steel

(Encyclopedia)steel, alloy of iron, carbon, and small proportions of other elements. Iron contains impurities in the form of silicon, phosphorus, sulfur, and manganese; steelmaking involves the removal of these imp...

steel industry

(Encyclopedia)steel industry, the business of processing iron ore into steel, which in its simplest form is an iron-carbon alloy, and in some cases, turning that metal into partially finished products or recycling ...

zinc

(Encyclopedia)zinc, metallic chemical element; symbol Zn; at. no. 30; at. wt. 65.38; m.p. 419.58℃; b.p. 907℃; sp. gr. 7.133 at 25℃; valence +2. Zinc is a lustrous bluish-white metal. It is found in Group 12 o...

electron

(Encyclopedia)electron, elementary particle carrying a unit charge of negative electricity. Ordinary electric current is the flow of electrons through a wire conductor (see electricity). The electron is one of the ...

diesel engine

(Encyclopedia)diesel engine, type of internal-combustion engine invented by the German engineer Rudolf Diesel and patented by him in 1892. Although his engine was designed to use coal dust as fuel, the diesel engin...

Curie

(Encyclopedia)Curie kürēˈ [key], family of French scientists. Pierre Curie, 1859–1906, scientist, and his wife, Marie Sklodowska Curie, 1867–1934, chemist and physicist, b. Warsaw, are known for their work o...