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gadolinium

(Encyclopedia)gadolinium gădəlĭnˈēəm [key], metallic chemical element; symbol Gd; at. no. 64; at. wt. 157.25; m.p. 1,312℃; b.p. 3,233℃; sp. gr. 7.898 at 25℃; valence +3. Gadolinium is a malleable, ducti...

amplifier

(Encyclopedia)amplifier, device that accepts a varying input signal and produces an output signal that varies in the same way as the input but has a larger amplitude. The input signal may be a current, a voltage, a...

James, P. D.

(Encyclopedia)James, P. D. (Phyllis Dorothy James White, Baroness James of Holland Park), 1920–2014, English mystery novelist, b. Oxford. From 1964 to 1979 she worked in the forensic science and criminal law divi...

electromagnet

(Encyclopedia)CE5 Electromagnet electromagnet, device in which magnetism is produced by an electric current. Any electric current produces a magnetic field, but the field near an ordinary straight conductor is ...

electronics

(Encyclopedia)electronics, science and technology based on and concerned with the controlled flow of electrons or other carriers of electric charge, especially in semiconductor devices. It is one of the principal b...

Coen Brothers

(Encyclopedia)Coen Brothers, American filmmakers Joel Coen, 1955–, and Ethan Coen, 1958–, both b. St. Louis Park, Minn. Joel studied at New York Univ. Film School (B.A., 1978), Ethan at Princeton (B.A., 1979). ...

Fassbinder, Rainer Werner

(Encyclopedia)Fassbinder, Rainer Werner rīˈnər vĕrˈnər fäsˈbĭnˌdər [key], 1946–82, German filmmaker, b. Bad Wörishofen, Bavaria. One of the most highly regarded and prolific directors of the post–Wo...

Poitier, Sir Sidney

(Encyclopedia)Poitier, Sir Sidney, 1927–2022, Bahamian-American actor, b. Miami, raised in the Bahamas, returned to the United States at 14. Poitier served in the 1...

Poroshenko, Petro Oleksiyovych

(Encyclopedia)Poroshenko, Petro Oleksiyovych pĕtrôˈ ôlĕksēˈyôvĭch pôrôshĕnˈkô [key], 1965–, Ukrainian political leader and businessman. He studied economics at Kiev State Univ. (grad. 1989) and went...

photochemistry

(Encyclopedia)photochemistry, study of chemical processes that are accompanied by or catalyzed by the emission or absorption of visible light or ultraviolet radiation. A molecule in its ground (unexcited) state can...