Columbia Encyclopedia

Search results

458 results found

zinc oxide

(Encyclopedia)zinc oxide, chemical compound, ZnO, that is nearly insoluble in water but soluble in acids or alkalies. It occurs as white hexagonal crystals or a white powder commonly known as zinc white. Zinc white...

Armey, Dick

(Encyclopedia)Armey, Dick (Richard Keith Armey) ärˈmē [key], 1940–, U.S. congressman, b. Cando, N.Dak., grad. Jamestown College, Univ. of Oklahoma (Ph.D.). A Republican and former economics professor at North ...

Gloucester, city, United States

(Encyclopedia)Gloucester, city (2020 pop. 29,729), Essex co., NE Mass., on Cape Ann; settled 1623, inc. as a city 1873. It is a port of entry at the head of Glouceste...

Yastrzemski, Carl Michael

(Encyclopedia)Yastrzemski, Carl Michael, 1939–, American baseball player, b. Southampton, N.Y. A career-long member of the Boston Red Sox, “Yaz” was signed in 1959, brought up to the majors in 1961 (replacing...

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 ...

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...

aspartic acid

(Encyclopedia)CE5 aspartic acid əspärˈtĭk [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer participates in the biosynthesis of proteins. Its acidi...

anhydride

(Encyclopedia)anhydride ănhīˈdrīd, –drĭd [key] [Gr.,=without water], chemical compound formed by removing water, H2O, from another compound; the anhydride can also react with water to form the original compo...

Davy, Sir Humphry

(Encyclopedia)Davy, Sir Humphry, 1778–1829, English chemist and physicist. The son of a woodcarver, he received his early education at Truro and was apprenticed (1795) to a surgeon-apothecary at Penzance. While d...

phenylketonuria

(Encyclopedia)phenylketonuria fĕnˌəlkētˌəno͝orˈēə [key] (PKU), inherited metabolic disorder caused by a deficiency in a specific enzyme (phenylalanine hydroxylase). The absence of this enzyme, a recessive...