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magnetic resonance

(Encyclopedia)magnetic resonance, in physics and chemistry, phenomenon produced by simultaneously applying a steady magnetic field and electromagnetic radiation (usually radio waves) to a sample of atoms and then a...

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...

Edwards, Jonathan, 1703–58, American theologian and metaphysician

(Encyclopedia)Edwards, Jonathan, 1703–58, American theologian and metaphysician, b. East Windsor (then in Windsor), Conn. He was a precocious child, early interested in things scientific, intellectual, and spirit...

binary star

(Encyclopedia)CE5 A. Eclipsing binary: Primary component passing behind secondary (dimmer) component B. Light curve for eclipsing binary binary star or binary system, pair of stars that are held together by the...

nerve gas

(Encyclopedia)nerve gas, any of several poison gases intended for military use, e.g., tabun, sarin, soman, and VX. Nerve gases were first developed by Germany during World War II but were not used at that time. The...

Netter, Frank Henry

(Encyclopedia)Netter, Frank Henry, 1906–1991, American physician and medical illustrator, b. Brooklyn, N.Y. He attended City College as well as the National Academy of Design and Art Students League and became a ...

Oder-Neisse line

(Encyclopedia)Oder-Neisse line, frontier established in 1945 between Germany and Poland; it followed the Oder and W Neisse rivers from the Baltic Sea to the Czechoslovak border. The boundary, desired by most Poles ...

Mi'kmaq

(Encyclopedia)Mi'kmaq or Micmac, Native North Americans whose language belongs to the Algonquian branch of the Algonquian-Wakashan linguistic stock (see Native American languages). They inhabit Nova Scotia, Cape Br...

Moro, Antonio

(Encyclopedia)Moro, Antonio môˈrō [key], c.1519–c.1575, Flemish portrait painter, known as Antonis Mor or Moor and as Sir Anthony More. He studied with Jan van Scorel. In 1547 he was a free master at Antwerp ...

thermionic emission

(Encyclopedia)thermionic emission thûrmˌīŏnˈĭk [key], emission of electrons or ions by substances that are highly heated, the charged particles being called thermions. The number of thermions emitted increase...