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Branly, Édouard

(Encyclopedia)Branly, Édouard ādwärˈ bräNlēˈ [key], French physicist and physician. He was professor of physics at the Catholic Institute, Paris, from 1875. He developed (1890) a coherer for the detection of...

Shklovsky, Iosif Samuilovich

(Encyclopedia)Shklovsky, Iosif Samuilovich yôsˈĭf səmo͞oēlˈəvĭch shklŏfˈskē [key], 1916–85, Soviet astronomer. He was head of the department of radio-astronomy at the Sternberg Astronomical Institute,...

magnetic resonance imaging

(Encyclopedia)magnetic resonance imaging (MRI), noninvasive diagnostic technique that uses nuclear magnetic resonance to produce cross-sectional images of organs and other internal body structures. The patient lies...

Rockefeller Center

(Encyclopedia)Rockefeller Center, complex of buildings in central Manhattan, New York City, between 48th and 51st streets and Fifth Ave. and the Ave. of the Americas (Sixth Ave.). The project was sponsored by John ...

satellite, artificial

(Encyclopedia)CE5 A. Nimbus weather satellite B. Syncom communications satellite satellite, artificial, object constructed by humans and placed in orbit around the earth or other celestial body (see also space ...

Motala

(Encyclopedia)Motala mo͞oˈtäˌlä [key], city (1990 pop. 29,630), Östergötland co., S Sweden, on Lake Vättern and on the Göta Canal. It is an important lake port and an industrial center. Manufactures includ...

direction finder

(Encyclopedia)direction finder, electronic device used to determine the position of a ship or aircraft. In a simple direction finder a radio receiver is equipped with a revolving directional antenna. The antenna re...

static

(Encyclopedia)static, term formerly use to describe electrical noise in radio reception, especially noise that originates outside a transmitter and receiver, e.g., in the atmosphere or in human-made devices. In gen...

sideband

(Encyclopedia)sideband, any frequency component of a modulated carrier wave other than the frequency of the carrier wave itself, i.e., any frequency added to the carrier as a result of modulation; sidebands carry t...

Hall, John Lewis

(Encyclopedia)Hall, John Lewis, 1934–, American physicist, b. Denver, Colo., Ph.D. Carnegie Institute of Technology, 1961. He has been a researcher at the National Bureau of Standards in Boulder, Colo., since 196...