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wax

(Encyclopedia)wax, substance secreted by glands on the abdomen of the bee and known commonly as beeswax; also various substances resembling beeswax. Waxes are mixtures comprising chiefly esters of monohydroxy alcoh...

Euripides

(Encyclopedia)Euripides yo͝orĭpˈĭdēz [key], 480 or 485–406 b.c., Greek tragic dramatist, ranking with Aeschylus and Sophocles. Born in Attica, he lived in Athens most of his life, though he spent much time o...

niobium

(Encyclopedia)niobium nīōˈbēəm [key], metallic chemical element; symbol Nb; at. no. 41; at. wt. 92.90638; m.p. about 2,468℃; b.p. 4,742℃; sp. gr. 8.57 at 20℃; valence +2, +3, +4, or +5. Niobium is a rare...

Nobel, Alfred Bernhard

(Encyclopedia)Nobel, Alfred Bernhard älˈfrĕd bĕrnˈhärd nōbĕlˈ [key], 1833–96, Swedish chemist and inventor. Educated in St. Petersburg, Russia, he traveled as a youth and returned to St. Petersburg in 18...

micromechanics

(Encyclopedia)micromechanics, the combination of minuscule electrical and mechanical components in a single device less than 1 mm across, such as a valve or a motor. Although micromechanical production processes an...

mixture

(Encyclopedia)mixture, in chemistry, a physical combination of two or more pure substances (i.e., elements or compounds). A mixture is distinguished from a compound, which is formed by the chemical combination of t...

Rush, Benjamin

(Encyclopedia)Rush, Benjamin, 1745?–1813, American physician, signer of the Declaration of Independence, b. Byberry (now part of Philadelphia), Pa., grad. College of New Jersey (now Princeton, 1760), M.D. Univ. o...

Sanger, Margaret Higgins

(Encyclopedia)Sanger, Margaret Higgins, 1879–1966, American leader in the birth control movement, b. Corning, N.Y. Personal experience and work as a public-health nurse, much of it on New York City's Lower East S...

Barnard, Frederick Augustus Porter

(Encyclopedia)Barnard, Frederick Augustus Porter, 1809–89, American educator and mathematician, b. Sheffield, Mass., grad. Yale, 1828. After tutoring at Yale and teaching in institutions for the deaf and mute, he...

combustion

(Encyclopedia)combustion, rapid chemical reaction of two or more substances with a characteristic liberation of heat and light; it is commonly called burning. The burning of a fuel (e.g., wood, coal, oil, or natura...