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ozone

(Encyclopedia)ozone ōˈzōn [key], an allotropic form of the chemical element oxygen (see allotropy). Pure ozone is an unstable, faintly bluish gas with a characteristic fresh, penetrating odor. The gas has a dens...

ozone layer

(Encyclopedia)ozone layer or ozonosphere, region of the stratosphere containing relatively high concentrations of ozone, located at altitudes of 12–30 mi (19–48 km) above the earth's surface. Ozone in the ozone...

Montreal Protocol

(Encyclopedia)Montreal Protocol, officially the Protocol on Substances That Deplete the Ozone Layer, treaty signed on Sept. 16, 1987, at Montreal by 25 nations; 197 nations are now parties to the accord. The protoc...

chlorofluorocarbons

(Encyclopedia)chlorofluorocarbons klōrˌəflo͝orˈəkärˌbənz, klôrˌ– [key] (CFCs), organic compounds that contain carbon, chlorine, and fluorine atoms. CFCs are highly effective refrigerants that were deve...

Crutzen, Paul Jozef

(Encyclopedia)Crutzen, Paul Jozef, 1933–2021, Dutch atmospheric chemist, grad. Univ. of Stockholm (Ph.D. 1968, D.Sc. 1973). After working (1977–80) for the Nation...

Rowland, Frank Sherwood

(Encyclopedia)Rowland, Frank Sherwood, 1927–2012, American chemist, b. Delaware, Ohio, Ph.D. Univ. of Chicago, 1952. Rowland taught at Princeton from 1952 to 1956 and at the Univ. of Kansas from 1956 to 1964, whe...

stratosphere

(Encyclopedia)stratosphere strătˈəsfēr [key], second lowest layer of the earth's atmosphere. The level from which it extends outward varies with latitude; it begins c.51⁄2 mi (9 km) above the poles, c.6 or 7 ...

Molina, Mario

(Encyclopedia)Molina, Mario (Mario José Molina-Pasquel y Henríquez), 1943–2020, Mexican chemist, Ph.D. Univ. of California, Berkeley, 1972. Molina was a professor at the Univ. of California, Irvine from 1975 to...

Schönbein, Christian Friedrich

(Encyclopedia)Schönbein, Christian Friedrich krĭsˈtyän frēˈdrĭkh shönˈbīn [key], 1799–1868, German chemist. From 1828 he taught at the Univ. of Basel (as professor from 1835). He discovered ozone (1840)...

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