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uncertainty principle

(Encyclopedia)uncertainty principle, physical principle, enunciated by Werner Heisenberg in 1927, that places an absolute, theoretical limit on the combined accuracy of certain pairs of simultaneous, related measur...

deuterium

(Encyclopedia)deuterium do͞otērˈēəm [key], isotope of hydrogen with mass no. 2. The deuterium nucleus, called a deuteron, contains one proton and one neutron. Deuterium is also called heavy hydrogen, and water...

Mottelson, Benjamin Roy

(Encyclopedia)Mottelson, Benjamin Roy, 1926–, Danish physicist, b. Chicago, Ph.D. Harvard, 1950. Raised and educated in the United States, he moved to Denmark, where he began work as a nuclear physicist. Mottelso...

Waterford, town, United States

(Encyclopedia)Waterford, town (1990 pop. 17,930), New London co., SE Conn., on Long Island Sound; settled c.1653, inc. as a separate town from New London, 1801. Mainly residential, it has a recording and film studi...

Whitehaven

(Encyclopedia)Whitehaven hwītˈhāvən [key], town (1991 pop. 27,512), Cumbria, NW England, at the mouth of Solway Firth. Whitehaven is a seaport and industrial town. There are chemical works, iron foundries, and ...

Rice University

(Encyclopedia)Rice University, at Houston, Tex.; coeducational; chartered 1891 as Rice Institute through a bequest of William Marsh Rice, opened 1912, renamed 1960. It follows the residential college system and has...

water, desalination of

(Encyclopedia)water, desalination of, process of removing soluble salts from water to render it suitable for drinking, irrigation, or industrial uses. The principal methods used for desalination include distillatio...

catalyst

(Encyclopedia)catalyst, substance that can cause a change in the rate of a chemical reaction without itself being consumed in the reaction; the changing of the reaction rate by use of a catalyst is called catalysis...

respiration

(Encyclopedia)CE5 Respiratory system respiration, process by which an organism exchanges gases with its environment. The term now refers to the overall process by which oxygen is abstracted from air and is tran...

Ritz, Walter

(Encyclopedia)Ritz, Walter, 1878–1909, Swiss physicist. He taught at the universities of Zürich and Göttingen. Ritz's combination principle, confirmed by later research, stated that the frequencies of spectral ...