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naphthol

(Encyclopedia)CE5 naphthol năfˈthôl [key], C10H7OH, either of two crystalline monohydric alcohols. The naphthols are position isomers, differing in the location of the hydroxyl group, –OH, on the carbon ske...

hydrate

(Encyclopedia)hydrate hīˈdrāt [key], chemical compound that contains water. A common hydrate is the familiar blue vitriol, a crystalline form of cupric sulfate. Chemically, it is cupric sulfate pentahydrate, CuS...

europium

(Encyclopedia)europium yo͝orōˈpēəm [key] [from Europe], metallic chemical element; symbol Eu; at. no. 63; at. wt. 151.964; m.p. about 820℃; b.p. about 1,600℃; sp. gr. 5.25 at 25℃; valence +2 or +3. Europ...

matter

(Encyclopedia)matter, anything that has mass and occupies space. Matter is sometimes called koinomatter (Gr. koinos=common) to distinguish it from antimatter, or matter composed of antiparticles. The atomic th...

polycarbonates

(Encyclopedia)polycarbonates, group of clear, thermoplastic polymers used mainly as molding compounds (see plastic). Polycarbonates are prepared by the reaction of an aromatic difunctional phenol with either phosge...

tunneling

(Encyclopedia)tunneling, quantum-mechanical effect by which a particle can penetrate a barrier into a region of space that would be forbidden by ordinary classical mechanics. Tunneling is a direct result of the wav...

't Hooft, Gerardus

(Encyclopedia)'t Hooft, Gerardus, 1946–, Dutch theoretical physicist, Ph.D. Univ. of Utrecht, 1972. He has been a professor at the Univ. of Utrecht since 1977. 't Hooft shared the 1999 Nobel Prize in Physics with...

Ringwood

(Encyclopedia)Ringwood, borough (1990 pop. 12,623), Passaic co., N N.J., in the Ramapo Mts. and on the Wanaque River near the N.Y. line. Iron was found nearby in 1730; mines and works were developed from 1764 by Pe...

Bridgman, Percy Williams

(Encyclopedia)Bridgman, Percy Williams, 1882–1961, American physicist, b. Cambridge, Mass., grad. Harvard (B.A., 1904; Ph.D., 1908). From 1910 he taught at Harvard, as professor from 1919. He won the 1946 Nobel P...

magic square

(Encyclopedia)magic square, a square divided into parts with letters or numbers inscribed therein that, whether combined vertically, horizontally, or diagonally, form the same sum or the same word. In ancient times...