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asparagine

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

aloe

(Encyclopedia)aloe ălˈō [key] [Gr.], any species of the genus Aloe, succulent perennials of the family Lilaceae (lily family), native chiefly to the warm dry areas of S Africa and also to tropical Africa, but cu...

DDT

(Encyclopedia)DDT or 2,2-bis(p-chlorophenyl)-1,1,1,-trichloroethane, chlorinated hydrocarbon compound used as an insecticide. First introduced during the 1940s, it killed insects that spread disease and fed on crop...

phenol

(Encyclopedia)phenol fēˈnōl [key], C6H5OH, a colorless, crystalline solid that melts at about 41℃, boils at 182℃, and is soluble in ethanol and ether and somewhat soluble in water. An aromatic alcohol, it ex...

refining

(Encyclopedia)refining, any of various processes for separating impurities from crude or semifinished materials. It includes the finer processes of metallurgy, the fractional distillation of petroleum into its comm...

sweetener, artificial

(Encyclopedia)sweetener, artificial, substance used as a low-calorie sugar substitute. Saccharin, cyclamates, and aspartame have been the most commonly used artificial sweeteners. Saccharin, a coal-tar derivative t...

air mass

(Encyclopedia)air mass, large body of air within the earth's atmosphere in which temperature and humidity, although varying at different heights, remain similar throughout the body at any one height. Air masses for...

actinide series

(Encyclopedia)actinide series, a series of radioactive metallic elements in Group 3 of the periodic table. Members of the series are often called actinides, although actinium (at. no. 89) is not always considered a...

tea

(Encyclopedia)tea, tree or bush, its leaves, and the beverage made from these leaves. The plant (Camellia sinensis, Thea sinensis, or C. thea) is an evergreen related to the camellia and indigenous to Assam (India)...

zirconium

(Encyclopedia)zirconium zərkōˈnēəm [key], metallic chemical element; symbol Zr; at. no. 40; at. wt. 91.224; m.p. about 1,852℃; b.p. 4,377℃; sp. gr. 6.5 at 20℃; valence +2, +3, or +4. Zirconium is a very ...