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Hinshelwood, Sir Cyril Norman

(Encyclopedia)Hinshelwood, Sir Cyril Norman, 1897–1967, British chemist, D.Sc. Oxford, 1924. In 1937 Hinshelwood became a professor at Oxford, where he remained until his retirement in 1964. He shared the 1956 No...

Döbereiner, Johann Wolfgang

(Encyclopedia)Döbereiner, Johann Wolfgang yōˈhän vôlfˈgäng döˈbərīnər [key], 1780–1849, German chemist. From 1810 he was professor of the Univ. of Jena. He is known especially for his discovery of sim...

Thénard, Louis Jacques

(Encyclopedia)Thénard, Louis Jacques lwē zhäk tānärˈ [key], 1777–1857, French chemist. He became professor at the Collège de France (1802), dean of the Faculty of Sciences, Paris (1821), chancellor of the ...

Ovshinsky, Stanford Robert

(Encyclopedia)Ovshinsky, Stanford Robert, 1922–2012, American inventor and scientist, b. Akron, Ohio. Self-taught, he developed a new type of lathe in the 1940s, the first of many innovations and patents. Special...

oxidases

(Encyclopedia)oxidases, in biochemistry, enzymes that catalyze reactions that directly involve molecular oxygen (see oxidation and reduction). Some utilize flavin coenzymes derived from riboflavin (see vitamin B2)....

Sörensen, Sören Peter Lauritz

(Encyclopedia)Sörensen, Sören Peter Lauritz söˈrən pēˈtər louˈrēts söˈrənsən [key], 1868–1939, Danish biochemist. In 1899 he received a Ph.D. degree in Copenhagen. Sörensen was director of chemistr...

combustion

(Encyclopedia)combustion, rapid chemical reaction of two or more substances with a characteristic liberation of heat and light; it is commonly called burning. The burning of a fuel (e.g., wood, coal, oil, or natura...

carbonyl group

(Encyclopedia)carbonyl group kärˈbənĭl [key], in chemistry, functional group that consists of an oxygen atom joined by a double bond to a carbon atom. The carbon atom is joined to the remainder of the molecule ...

computer virus

(Encyclopedia)computer virus, rogue computer program, typically a short program designed to disperse copies of itself to other computers and disrupt those computers' normal operations. A computer virus usually atta...

ammonia

(Encyclopedia)ammonia, chemical compound, NH3, colorless gas that is about one half as dense as air at ordinary temperatures and pressures. It has a characteristic pungent, penetrating odor. Ammonia forms a minute ...