Columbia Encyclopedia

Search results

438 results found

Hot Springs

(Encyclopedia)Hot Springs. <1> City (2020 pop. 37,930), seat of Garland co., W central Ark.; settled 1807, inc. 1876. The city nearly surrounds Hot Springs Nati...

string theory

(Encyclopedia)string theory, description of elementary particles based on one-dimensional curves, or “strings,” instead of point particles. Superstring theory, which is string theory that contains a kind of sym...

rose of Jericho

(Encyclopedia)rose of Jericho, common name for two plants belonging to different families in the plant kingdom. One, an annual desert plant (Anastatica hierochuntica) of the family Cruciferae (or Brassicaceae; must...

Reines, Frederick

(Encyclopedia)Reines, Frederick, 1918–99, American physicist, b. Paterson, N.J., Ph.D. New York Univ., 1944. He was a researcher at Los Alamos National Laboratory (1944–59), a professor at Case Institute of Tec...

helium

(Encyclopedia)helium hēˈlēəm [key], gaseous chemical element; symbol He; at. no. 2; at. wt. 4.0026; m.p. below −272℃ at 26 atmospheres pressure; b.p. −268.934℃ at 1 atmosphere pressure; density 0.1785 g...

silicon

(Encyclopedia)silicon, nonmetallic chemical element; symbol Si; at. no. 14; interval in which at. wt. ranges 28.084–28.086; m.p. 1,410℃; b.p. 2,355℃; sp. gr. 2.33 at 25℃; valence usually +4. Silicon is the ...

Dasht-e Kavir

(Encyclopedia)Dasht-e Kavir däsht-ēkävērˈ [key], great salt desert, c.500 mi (800 km) long and c.200 mi (320 km) wide, SE of the Elburz Mts., N central Iran. It is a huge basin of interior drainage named after...

Hassel, Odd

(Encyclopedia)Hassel, Odd ôd häsˈəl [key], 1897–1981, Norwegian chemist, b. Christiania (now Oslo), grad. Oslo Univ. (1920), Ph.D. Univ. of Berlin (1924). After pursuing X-ray crystallographic studies in Germ...

geochemistry

(Encyclopedia)geochemistry, study of the chemical changes on the earth. More specifically, it is the study of the absolute and relative abundances of chemical elements in the minerals, soils, ores, rocks, water, an...

gasohol

(Encyclopedia)gasohol, a gasoline extender made from a mixture of gasoline (90%) and ethanol (10%; often obtained by fermenting agricultural crops or crop wastes) or gasoline (97%) and methanol, or wood alcohol (3%...