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Coxe, William

(Encyclopedia)Coxe, William, 1762–1831, American pomologist, b. Philadelphia. His experiments and his book, A View of the Cultivation of Fruit-Trees and the Management of Orchards and Cider (1817), had a pronounc...

paregoric

(Encyclopedia)paregoric pârˌəgôrˈĭk [key], alcoholic solution of opium and camphor first prepared in the 18th cent. Because of the constipating effect of opium, paregoric has been used to control diarrhea. It...

Cherenkov radiation

(Encyclopedia)Cherenkov radiation or Cerenkov radiation [for P. A. Cherenkov], light emitted by a transparent medium when charged particles pass through it at a speed greater than the speed of light in the medium. ...

venom

(Encyclopedia)venom or zootoxin, any of a variety of poisonous substances produced by animals. In poisonous snakes, venom is secreted in two poison glands, one on each side of the upper jaw, and enters the fang by ...

radiometer

(Encyclopedia)radiometer rāˌdēŏmˈətər [key], instrument for detection or measurement of electromagnetic radiation; the term is applied in particular to devices used to measure infrared radiation. One of the ...

von Klitzing, Klaus

(Encyclopedia)von Klitzing, Klaus, 1943–, German physicist, Ph.D. Univ. of Würzburg, 1972. He was a professor at the Technical Univ. of Munich (1980–85) and then director of the Max Planck Institute for Solid ...

perturbation

(Encyclopedia)perturbation pŭrˌtərbāˈshən [key], in astronomy and physics, small force or other influence that modifies the otherwise simple motion of some object. The term is also used for the effect produce...

impasto

(Encyclopedia)impasto ĭmpăsˈtō, –päˈstō [key], thickly applied paint that projects from the picture surface. Such works as Childe Hassam's Allies Day (1917; National Gall. of Art, Washington, D.C.) and Han...

Magendie, François

(Encyclopedia)Magendie, François fräNswäˈ mäzhäNdēˈ [key], 1783–1855, French physician. He taught at the Collège de France and is considered a founder of experimental physiology. He distinguished the mot...

Brownian movement

(Encyclopedia)Brownian movement or motion, zigzag, irregular motion exhibited by minute particles of matter when suspended in a fluid. The effect has been observed in all types of colloidal suspensions (see colloid...