Columbia Encyclopedia

Search results

500 results found

selenium

(Encyclopedia)selenium səlēˈnēəm [key], nonmetallic chemical element; symbol Se; at. no. 34; at. wt. 78.96; m.p. 217℃; b.p. about 685℃; sp. gr. 4.81 at 20℃; valence −2, +4, or +6. Selenium is directly ...

Shenyang

(Encyclopedia)Shenyang mo͞okˈdŭn [key], city (1994 est. pop. 3,762,000), capital of Liaoning prov., NE China, on the Hun River. It is China's fourth largest city and the leading manufacturing hub in a highly ind...

photoelectric effect

(Encyclopedia)photoelectric effect, emission of electrons by substances, especially metals, when light falls on their surfaces. The effect was discovered by H. R. Hertz in 1887. The failure of the classical theory ...

Price, Vincent Leonard, Jr.

(Encyclopedia) Price, Vincent Leonard, Jr., 1911-93, American film actor, b. St. Louis, Mo., Yale Univ. (B.A., 1933). Price studied English and art in college and th...

cerium

(Encyclopedia)cerium sērˈēəm [key] [from the asteroid Ceres], metallic chemical element; symbol Ce; at. no. 58; at. wt. 140.116; m.p. 799℃; b.p. 3,426℃; sp. gr. 6.77 at 25℃; valence +3 or +4. Cerium is a ...

Balkan Peninsula

(Encyclopedia)Balkan Peninsula, southeasternmost peninsula of Europe, c.200,000 sq mi (518,000 sq km), bounded by the Black Sea, Sea of Marmara, Aegean Sea, Mediterranean Sea, Ionian Sea, and Adriatic Sea. Although...

radioactive isotope

(Encyclopedia)radioactive isotope or radioisotope, natural or artificially created isotope of a chemical element having an unstable nucleus that decays, emitting alpha, beta, or gamma rays until stability is reache...

dating

(Encyclopedia)dating, the determination of the age of an object, of a natural phenomenon, or of a series of events. There are two basic types of dating methods, relative and absolute. In relative dating, the tempor...

Iberville, Pierre le Moyne, sieur d'

(Encyclopedia)Iberville, Pierre le Moyne, sieur d' pyĕr lə mwän syör dēbĕrvēlˈ [key], 1661–1706, French Canadian naval officer, founder of the French territory of Louisiana, b. Ville Marie (in present Mon...

Henan

(Encyclopedia)Henan or Honan both: ho͝oˈnänˈ [key], province, c.65,000 sq mi (168,350 sq km), NE China. The capital is ...