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hydrocarbon

(Encyclopedia)hydrocarbon hīˌdrōkärˈbən [key], any organic compound composed solely of the elements hydrogen and carbon. The hydrocarbons differ both in the total number of carbon and hydrogen atoms in their ...

holography

(Encyclopedia)holography hŏlŏgˈrəfē, hō– [key], method of reproducing a three-dimensional image of an object by means of light wave patterns recorded on a photographic plate or film. Holography is sometimes...

gourd

(Encyclopedia)CE5 Wild balsam apple, Echinocystis Jobata, a member of the gourd family gourd gôrd, go͝ord [key], common name for some members of the Cucurbitaceae, a family of plants whose range includes all ...

molybdenum

(Encyclopedia)molybdenum məlĭbˈdənəm [key] [Gr.,=leadlike], metallic chemical element; symbol Mo; at. no. 42; at. wt. 95.96; m.p. about 2,617℃; b.p. about 4,612℃; sp. gr. 10.22 at 20℃; valence +2, +3, +4...

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...

Lollardry

(Encyclopedia)Lollardry lŏlˈyo͝ordrē [key] or Lollardy, medieval English movement for ecclesiastical reform, led by John Wyclif, whose “poor priests” spread his ideas about the countryside in the late 14th ...

Koch

(Encyclopedia)Koch kōk [key], family of American industrialists and philanthropists. Fred Chase Koch, 1900–1967, b. Quanah, Tex., grad. Massachusetts Institute of Technology, 1922, was a Wichita, Kans., entrepre...

particle detector

(Encyclopedia)CE5 Particle detector—Bubble chamber: A. Pressure drops as piston is raised; B. Charged particles passing through chamber ionize atoms in liquid; C. Bubbles form around atoms and form visible tra...

trust

(Encyclopedia)trust, in law, arrangement whereby property legally owned by one person is administered for the benefit of another. Three parties are ordinarily needed for the relation to arise: the settlor, who bequ...

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...