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photon

(Encyclopedia)photon fōˈtŏn [key], the particle composing light and other forms of electromagnetic radiation, sometimes called light quantum. The photon has no charge and no mass. About the beginning of the 20th...

caper

(Encyclopedia)caper, common name for members of the Capparidaceae, a family of tropical plants found chiefly in the Old World and closely related to the family Cruciferae (or Brassicaceae; mustard family). Capparis...

Dewey, John

(Encyclopedia)Dewey, John, 1859–1952, American philosopher and educator, b. Burlington, Vt., grad. Univ. of Vermont, 1879, Ph.D. Johns Hopkins, 1884. He taught at the universities of Minnesota (1888–89), Michig...

cysteine

(Encyclopedia)CE5 CE5 cysteine sĭsˈtēn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer participates in the biosynthesis of mammalian protein...

icon

(Encyclopedia)icon [Gr. eikon=image], single image created as a focal point of religious veneration, especially a painted or carved portable object of the Orthodox Eastern faith. Icons commonly represent Christ Pan...

narcotic

(Encyclopedia)narcotic, any of a number of substances that have a depressant effect on the nervous system. The chief narcotic drugs are opium, its constituents morphine and codeine, and the morphine derivative hero...

spiritual

(Encyclopedia)spiritual, a religious folk song of American origin, particularly associated with African-American Protestants of the southern United States. The African-American spiritual, characterized by syncopati...

titanium

(Encyclopedia)titanium tītāˈnēəm, tĭ– [key] [from Titan], metallic chemical element; symbol Ti; at. no. 22; at. wt. 47.867; m.p. 1,675℃; b.p. 3,260℃; sp. gr. 4.54 at 20℃; valence +2, +3, or +4. Titani...

photoelectric cell

(Encyclopedia)CE5 Photoelectric cell: Light causes a photosensitive surface to emit electrons, which flow as current to the positive terminal. A galvanometer measures the current and thus indicates light intensi...

Dolomites

(Encyclopedia)Dolomites or Dolomite Alps, Alpine group, N Italy, between the Isarco and Piave rivers, named for the dolomitic limestone of which it is composed. Famous for their strikingly bold outline (a stairstep...