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hydrogenation

(Encyclopedia)hydrogenation hīdrôjˈənāˌshən, hīˌdrəjənāˈshən [key], chemical reaction of a substance with molecular hydrogen, usually in the presence of a catalyst. A common hydrogenation is the harde...

Ibizan hound

(Encyclopedia)Ibizan hound ēbēˈzŏn, ĭbˈə– [key], also called Ibizan Podenco, breed of tall, swift dog of ancient origin now found chiefly in the Balearic Islands and other areas of Spain. It stands from 22...

alloy

(Encyclopedia)alloy ălˈoi, əloiˈ [key] [O. Fr.,=combine], substance with metallic properties that consists of a metal fused with one or more metals or nonmetals. Alloys may be a homogeneous solid solution, a he...

coronagraph

(Encyclopedia)coronagraph kərōˈnəgrăfˌ [key], device invented by the French astronomer B. Lyot (1931) for the purpose of observing the corona of the sun and solar prominences occurring in the chromosphere. Be...

cylinder

(Encyclopedia)CE5 Cylinder cylinder, in mathematics, surface generated by a line moving parallel to a given fixed line and continually intersecting a given fixed curve called the directrix; each line of the fam...

dachshund

(Encyclopedia)dachshund dăksˈho͝ond, –ənd, dăshˈ– [key], breed of small, short-legged hound developed in Germany over hundreds of years. It stands from 5 to 9 in. (13–23 cm) high at the shoulder and wei...

cocker spaniel

(Encyclopedia)cocker spaniel, breed of small sporting dog developed from English cocker spaniels brought to the United States in the 1880s. It stands from 14 to 15 in. (35.6–38.1 cm) high at the shoulder and weig...

English setter

(Encyclopedia)English setter, breed of large sporting dog developed over hundreds of years in England. It stands about 25 in. (63.5 cm) high at the shoulder and weighs about 60 lb (27.2 kg). Its flat or slightly wa...

Pembroke Welsh corgi

(Encyclopedia)Pembroke Welsh corgi, breed of short-legged, hardy working dog thought to have been introduced into South Wales by Flemish immigrants in the early 12th cent. It stands from 10 to 12 in. (25.4–30.5 c...

pencil

(Encyclopedia)pencil, pointed implement used in writing or drawing to apply graphite or a similar colored solid to any surface, especially paper. From prehistoric times lumps of colored earth or chalk were used as ...