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oxidation and reduction

(Encyclopedia)oxidation and reduction, complementary chemical reactions characterized by the loss or gain, respectively, of one or more electrons by an atom or molecule. Originally the term oxidation was used to re...

potentiometer

(Encyclopedia)potentiometer. 1 Manually adjustable, variable, electrical resistor. It has a resistance element that is attached to the circuit by three contacts, or terminals. The ends of the resistance element are...

hahnium

(Encyclopedia)hahnium hänˈēəm [key], symbol Ha, former suggested name for both element 105, now called dubnium, and element 108, now called hassium. ...

nielsbohrium

(Encyclopedia)nielsbohrium nēlzbôrˈēəm [key], symbol Ns, former suggested name for both element 105, now called dubnium, and element 107, now called bohrium. ...

cornice

(Encyclopedia)cornice kôrˈnĭs [key], molded or decorated projection that forms the crowning feature at the top of a building wall or other architectural element; specifically, the uppermost of the three principa...

Garland, Judy

(Encyclopedia)Garland, Judy, 1922–69, American singer and film actress, b. Grand Rapids, Minn., originally named Frances Gumm. She sang in her father's theater from the age of four as one of The Gumm Sisters; she...

carbon

(Encyclopedia)CE5 The three solid forms of pure carbon: In the diamond crystal each carbon atom is surrounded symmetrically by four other carbons (at each of the four corners of a tetrahedron). In the graphite c...

electronics industry

(Encyclopedia)electronics industry, the business of creating, designing, producing, and selling devices such as radios, televisions, stereos, computers, semiconductors, transistors, and integrated circuits (see ele...

nitrogen

(Encyclopedia)nitrogen nīˈtrəjən [key], gaseous chemical element; symbol N; at. no. 7; interval in which at. wt. ranges 14.00643–14.00728; m.p. −209.86℃; b.p. −195.8℃; density 1.25 grams per liter at ...

bolometer

(Encyclopedia)bolometer bōlŏmˈətər, bə– [key], instrument for detecting and measuring radiation, e.g., visible light, infrared radiation, and ultraviolet radiation, in amounts as small as one millionth of a...