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acne

(Encyclopedia)acne, common inflammatory disease of the hair follicles and sebaceous glands characterized by blackheads, whiteheads, pustules, nodules and, in the more severe forms, by cysts and scarring. The lesion...

sting

(Encyclopedia)sting, in zoology, organ found in bees, many wasps, some ants, and in scorpions and sting rays, used defensively as well as to kill or paralyze prey. In the bee and the wasp the venom is produced by g...

sulfa drug

(Encyclopedia)sulfa drug, any of a class of synthetic chemical substances derived from sulfanilamide, or para-aminobenzenesulfonamide. Sulfa drugs are used to treat bacterial infections, although they have largely ...

cassava

(Encyclopedia)cassava mănˈēŏk [key], name for many species of the genus Manihot of the family Euphorbiaceae (spurge family). The roots, which resemble sweet potatoes and are eaten in much the same way, yield ca...

bismuth

(Encyclopedia)bismuth bĭzˈməth [key] [Ger. Weisse Masse=white mass], metallic chemical element; symbol Bi; at. no. 83; at. wt. 208.98040; m.p. 271.3℃; b.p. about 1,560℃; sp. gr. 9.75 at 20℃; valence +3 or ...

bleaching

(Encyclopedia)bleaching, process of whitening by chemicals or by exposure to sun and air, commonly applied to textiles, paper pulp, wheat flour, petroleum products, oils and fats, straw, hair, feathers, and wood. C...

Langmuir, Irving

(Encyclopedia)Langmuir, Irving lăngˈmyo͞or [key], 1881–1957, American chemist, b. Brooklyn, N.Y. Associated (1909–50) with the research laboratory of the General Electric Company, he introduced atomic-hydrog...

Imperial Valley

(Encyclopedia)Imperial Valley, fertile region in the Colorado Desert, SE Calif., extending S into NW Mexico. Once part of the Gulf of California, most of the region is below sea level; its lowest point is −232 ft...

chicle

(Encyclopedia)chicle chĭkˈəl [key], name for the gum obtained from the latex of the sapodilla tree (Manilkara zapota), a tropical American evergreen. The sapodilla (known also by many other common names) is wide...

Priestley, J. B.

(Encyclopedia)Priestley, J. B. (John Boynton Priestley), 1894–1984, English author. An extraordinarily prolific writer, Priestley worked in a variety of genres. He first wrote literary criticism as a student at C...