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superconductivity

(Encyclopedia)superconductivity, abnormally high electrical conductivity of certain substances. The phenomenon was discovered in 1911 by Heike Kamerlingh Onnes, who found that the resistance of mercury dropped sudd...

soap

(Encyclopedia)soap, a cleansing agent. It cleanses by lowering the surface tension of water, by emulsifying grease, and by absorbing dirt into the foam. Ancient peoples are believed to have employed wood ashes and ...

Piedmont, region, Italy

(Encyclopedia)Piedmont pēdˈmŏnt [key], Ital. Piemonte, region (1991 pop. 4,302,565), 9,807 sq mi (25,400 sq km), NW Italy, bordering on France in the west and on Switzerland in the north. Turin is the capital of...

semiconductor

(Encyclopedia)CE5 N-type and P-type crystals: In a pure silicon crystal each silicon atom (Si) is surrounded by four valence electrons. In the N-doped semiconductor, illustrated in the left-hand figure, some sil...

Sichuan

(Encyclopedia)Sichuan or Szechwan sŭˈchwänˈ [key] [four rivers], province (2010 pop. 80,418,200), c.220,000 sq mi (569,800 sq km), SW China. The capital is Chengdu. A naturally isolated region surrounded by 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...

laser

(Encyclopedia)CE5 Ordinary light sources produce incoherent light, while a laser produces a beam of coherent light. laser [acronym for light amplification by stimulated emission of radiation], device for the cr...

Tajikistan

(Encyclopedia)CE5 Tajikistan təjĭkĭstänˈ [key], officially Republic of Tajikistan, republic (2015 est. pop. 8,192,000), 55,251 sq mi (143,100 sq km), central Asia. It borders on China in the east, Afghanist...

Cameroon, country

(Encyclopedia)CE5 Cameroon kămˌəro͞onˈ [key], Fr. Cameroun, officially Republic of Cameroon, republ...

Gehry, Frank Owen

(Encyclopedia)Gehry, Frank Owen gĕrˈē [key], 1929–, American architect, b. Toronto, Ont., as Frank Owen Goldberg. He is widely considered one of the finest and most artful of contemporary architects. In 1947, ...