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pasteurization

(Encyclopedia)pasteurization păsˌcho͝orĭzāˈshən, –rīzāˈshən [key], partial sterilization of liquids such as milk, orange juice, wine, and beer, as well as cheese, to destroy disease-causing and other u...

flame test

(Encyclopedia)flame test, test used in the identification of certain metals. It is based on the observation that light emitted by any element gives a unique spectrum when passed through a spectroscope. When a salt ...

ammonium nitrate

(Encyclopedia)ammonium nitrate, chemical compound, NH4NO3, that exists as colorless, rhombohedral crystals at room temperature but changes to monoclinic crystals when heated above 32℃. It is extremely soluble in ...

isopropanol

(Encyclopedia)isopropanol, isopropyl alcohol, or 2-propanol īˌsəprōˈpənōl, īˌsəprōˈpĭl [key], (CH3)2CHOH, a colorless liquid that is miscible with water. It melts at −89℃ and boils at 82.3℃. It ...

electrolyte

(Encyclopedia)electrolyte ĭlĕkˈtrəlītˌ [key], electrical conductor in which current is carried by ions rather than by free electrons (as in a metal). Electrolytes include water solutions of acids, bases, or s...

ketoprofen

(Encyclopedia)ketoprofen kēˌtəprōˈfĭn [key], nonsteroidal anti-inflammatory drug (NSAID) with anti-inflammatory, analgesic, and fever-reducing effects, used to relieve the symptoms of headaches, arthritis, an...

basic oxygen process

(Encyclopedia)basic oxygen process, method of producing steel from a charge consisting mostly of pig iron. The charge is placed in a furnace similar to the one used in the Bessemer process of steelmaking except tha...

Williams, Roger John

(Encyclopedia)Williams, Roger John, 1893–1988, American chemist, b. India, grad. Univ. of Redlands, Redlands, Calif. (B.S., 1914), Ph.D. Univ. of Chicago, 1919; brother of the chemist Robert R. Williams, Jr. He t...

viscose process

(Encyclopedia)viscose process vĭsˈkōs [key], method widely used for the commercial preparation of rayon. Cellulose, prepared from either wood pulp or, less commonly, cotton linters, is treated with sodium hydrox...

rayon

(Encyclopedia)rayon, synthetic fibers made from cellulose or textiles woven from such fibers; more rayon is manufactured than any other synthetic fiber. The name was adopted (1924), in preference to “artificial s...