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thermoelectricity

(Encyclopedia)thermoelectricity, direct conversion of heat into electric energy, or vice versa. The term is generally restricted to the irreversible conversion of electricity into heat described by the English phys...

Tharp, Twyla

(Encyclopedia)Tharp, Twyla twīˈlə [key], 1941–, American dancer and choreographer, b. Portland, Ind. An eclectic, innovative choreographer and dancer, she danced (1963–65) with Paul Taylor. For more than 20 ...

North American Free Trade Agreement

(Encyclopedia)North American Free Trade Agreement (NAFTA), accord establishing a free-trade zone in North America; it was signed in 1992 by Canada, Mexico, and the United States and took effect on Jan. 1, 1994. NAF...

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...

Odinga, Raila Amolo

(Encyclopedia)Odinga, Raila Amolo ōdĭnˈgä [key] 1945–, Kenyan political leader, son of Oginga Odinga, Kenya's first vice president. After earning (1970) a degree in mechanical engineering from the Univ. of M...

solid

(Encyclopedia)solid, one of the three commonly recognized states in which matter occurs, i.e., that state, as distinguished from liquid and gas, in which a substance has both a definite shape and a definite volume....

Benn, Anthony Wedgwood

(Encyclopedia)Benn, Anthony Wedgwood (Tony Benn), 1925–2014, British politician, b. London, grad. New College, Oxford. After working for the British Broadcasting Corporation (1949–50), he was elected a Labour m...

uracil

(Encyclopedia)uracil yo͝orˈəsĭl [key], organic base of the pyrimidine family. It was isolated from herring sperm and also produced in a laboratory in 1900–1901. When combined with the sugar ribose in a glycos...

urinalysis

(Encyclopedia)urinalysis yo͝orˌənălˈĭsĭs [key], clinical examination of urine for the purpose of medical diagnosis. Urine is initially examined for such characteristics as color, odor, and specific gravity. ...

water mold

(Encyclopedia)water mold, common name for a group of multinucleated organisms that superficially resemble fungi but are now recognized as having an independent evolutionary lineage and are placed in the kingdom Pro...