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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...

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...

liquid crystal

(Encyclopedia)liquid crystal, liquid whose component particles, atoms or molecules, tend to arrange themselves with a degree of order far exceeding that found in ordinary liquids and approaching that of solid cryst...

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...

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...

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...

'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...

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...

Dacron

(Encyclopedia)Dacron dāˈkrŏn, dăkˈrŏn [key], trademark for a polyester fiber. Dacron is a condensation polymer obtained from ethylene glycol and terephthalic acid. Its properties include high tensile strength...