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Pará rubber tree

(Encyclopedia)Pará rubber tree päräˈ [key], large tree (Hevea brasiliensis) of the family Euphorbiaceae (spurge family), native to tropical South America and the source of the greatest amount and finest quality...

nitric oxide

(Encyclopedia)nitric oxide or nitrogen monoxide, a colorless gas formed by the combustion of nitrogen and oxygen as given by the reaction: energy + N2 + O2 → 2NO; m.p. −163.6℃; b.p. −151.8℃. Nitric oxide ...

auxin

(Encyclopedia)auxin ôkˈsĭn [key], plant hormone that regulates the amount, type, and direction of plant growth. Auxins include both naturally occurring substances and related synthetic compounds that have simila...

cadmium

(Encyclopedia)cadmium kădˈmēəm [key] [from cadmia, Lat. for calamine, with which cadmium is found associated], metallic chemical element; symbol Cd; at. no. 48; at. wt. 112.411; m.p. 321℃; b.p. 765℃; sp. gr...

bog

(Encyclopedia)bog, very old lake without inlet or outlet that becomes acid and is gradually overgrown with a characteristic vegetation (see swamp). Peat moss, or sphagnum, grows around the edge of the open water of...

Bolshoi Ballet

(Encyclopedia)Bolshoi Ballet bōlˈshoi, bôlˈ– [key], one of the principal ballet companies of Russia; part of the Bolshoi Theatre, which also includes Russia's premier opera company. The Bolshoi Ballet began a...

Watson, James Dewey

(Encyclopedia)Watson, James Dewey, 1928–, American biologist and educator, b. Chicago, Ill., grad. Univ. of Chicago, 1947, Ph.D. Univ. of Indiana, 1950. With F. H. C. Crick he began (1951) research on the molecul...

fats and oils

(Encyclopedia)fats and oils, group of organic substances that form an important part of the diet and also are useful in many industries. The fats are usually solid, the oils generally liquid at ordinary room temper...

asbestos, mineral

(Encyclopedia)asbestos, common name for any of a variety of silicate minerals within the amphibole and serpentine groups that are fibrous in structure and more or less resistant to acid and fire. Chrysotile asbesto...

hydrometer

(Encyclopedia)hydrometer hīdrŏmˈətər [key], device used to determine directly the specific gravity of a liquid. It usually consists of a thin glass tube closed at both ends, with one end enlarged into a bulb t...