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magnetic resonance

(Encyclopedia)magnetic resonance, in physics and chemistry, phenomenon produced by simultaneously applying a steady magnetic field and electromagnetic radiation (usually radio waves) to a sample of atoms and then a...

maser

(Encyclopedia)maser māˈzər [key], device for creation, amplification, and transmission of an intense, highly focused beam of high-frequency radio waves. The name maser is an acronym for microwave amplification b...

semiconductor

(Encyclopedia)CE5 N-type and P-type crystals: In a pure silicon crystal each silicon atom (Si) is surrounded by four valence electrons. In the N-doped semiconductor, illustrated in the left-hand figure, some sil...

condensate

(Encyclopedia)condensate, matter in the form of a gas of atoms, molecules, or elementary particles that have been so chilled that their motion is virtually halted and as a consequence they lose their separate ident...

polymer

(Encyclopedia)CE5 A. Addition polymerization: Two ethylene molecules, C2H4, combine to form two links in the polyethylene chain molecule (C2H4)n. B. Condensation polymerization: Two glycine molecules, NH2CH2COOH...

oganesson

(Encyclopedia)oganesson ōˈgənĕsˌən [key], artificially produced radioactive chemical element; symbol Og; at. no. 118; mass number of most stable isotope 294; m.p., b.p., sp. gr., and valence unknown. Situated...

carbon

(Encyclopedia)CE5 The three solid forms of pure carbon: In the diamond crystal each carbon atom is surrounded symmetrically by four other carbons (at each of the four corners of a tetrahedron). In the graphite c...

vestments

(Encyclopedia)vestments, garments worn by ecclesiastics in ceremonial functions. The cassock, a close-fitting gown buttoning down the front and reaching to the feet, is not a vestment so much as the daily uniform o...

Daniel, book of the Bible

(Encyclopedia)Daniel, book of the Bible. It combines “court” tales, perhaps originating from the 6th cent. b.c., and a series of apocalyptic visions arising from the time of the Maccabean emergency (167–164 b...

Wilder, Thornton Niven

(Encyclopedia)Wilder, Thornton Niven, 1897–1975, American playwright and novelist, b. Madison, Wis., grad. Yale (B.A., 1920), Princeton (M.A., 1925). He received most of his early education in China, where his fa...