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infrared radiation
(Encyclopedia)infrared radiation, electromagnetic radiation having a wavelength in the range from c.75 × 10−6 cm to c.100,000 × 10−6 cm (0.000075–0.1 cm). Infrared rays thus occupy that part of the electrom...gamma radiation
(Encyclopedia)gamma radiation, high-energy photons emitted as one of the three types of radiation resulting from natural radioactivity. It is the most energetic form of electromagnetic radiation, with a very short ...Cerenkov radiation
(Encyclopedia)Cerenkov radiation: see Cherenkov radiation. ...synchrotron radiation
(Encyclopedia)synchrotron radiation, in physics, electromagnetic radiation emitted by high-speed electrons spiraling along the lines of force of a magnetic field (see magnetism). Depending on the electron's energy ...adaptive radiation
(Encyclopedia)CE5 Adaptive radiation in Hawaiian honey-creepers adaptive radiation, in biology, the evolution of an ancestral species, which was adapted to a particular way of life, into many diverse species, e...ultraviolet radiation
(Encyclopedia)ultraviolet radiation, invisible electromagnetic radiation between visible violet light and X rays; it ranges in wavelength from about 400 to 4 nanometers and in frequency from about 1015 to 1017 hert...radiation chemistry
(Encyclopedia)radiation chemistry: see radiochemistry. ...radiation sickness
(Encyclopedia)radiation sickness, harmful effect produced on body tissues by exposure to radioactive substances. The biological action of radiation is not fully understood, but it is believed that a disturbance in ...radiation weapon
(Encyclopedia)radiation weapon or radiological weapon, a bomb or warhead that uses conventional chemical explosives to disperse radioactive material, sometimes called a “dirty bomb.” Designed to produce radiati...Allen, Richard
(Encyclopedia)Allen, Richard, 1760–1831, American clergyman, founder of the African Methodist Episcopal Church. He was born a slave in Philadelphia and purchased his freedom. He became pastor of a black group tha...Browse by Subject
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