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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...

sodium hydroxide

(Encyclopedia)sodium hydroxide, chemical compound, NaOH, a white crystalline substance that readily absorbs carbon dioxide and moisture from the air. It is very soluble in water, alcohol, and glycerin. It is a caus...

iodine

(Encyclopedia)iodine īˈədīn, –dĭn [key] [Gr.,=violet], nonmetallic chemical element; symbol I; at. no. 53; at. wt. 126.90447; m.p. 113.5℃; b.p. 184.35℃; sp. gr. 4.93 at 20℃; valence −1, +1, +3, +5, o...

antifreeze

(Encyclopedia)antifreeze, substance added to a solvent to lower its freezing point. The solution formed is called an antifreeze mixture. Antifreeze is typically added to water in the cooling system of an internal-c...

salt, chemical compound

(Encyclopedia)salt, chemical compound (other than water) formed by a chemical reaction between an acid and a base (see acids and bases). Salts are also prepared by methods other than neutralization. A metal can c...

dip

(Encyclopedia)dip, in agriculture, method of treating animals (chiefly livestock) infested with skin parasites such as mites, ticks, and warbles. The animal is dipped into or forced to swim through a tank filled wi...

phosphorescence

(Encyclopedia)phosphorescence fŏsˌfərĕsˈəns [key], luminescence produced by certain substances after absorbing radiant energy or other types of energy. Phosphorescence is distinguished from fluorescence in th...

ammonia

(Encyclopedia)ammonia, chemical compound, NH3, colorless gas that is about one half as dense as air at ordinary temperatures and pressures. It has a characteristic pungent, penetrating odor. Ammonia forms a minute ...

Garnier, Tony

(Encyclopedia)Garnier, Tony, 1869–1948, French architect. His greatest achievement was in urban planning. After his study of sociological and architectural problems of an industrial city, he began in 1901 to form...

polymerase chain reaction

(Encyclopedia)polymerase chain reaction pŏlˈĭmərāsˌ [key] (PCR), laboratory process in which a particular DNA segment from a mixture of DNA chains is rapidly replicated, producing a large, readily analyzed sa...