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phenyl

(Encyclopedia)phenyl fĕnˈəl [key], C6H5, organic free radical or alkyl group derived from benzene by removing one hydrogen atom. ...

polyester

(Encyclopedia)polyester, synthetic fiber, produced by the polymerization of the product formed when an alcohol and organic acid react. The outstanding characteristic of polyesters is their ability to resist wrinkli...

vulcanization

(Encyclopedia)vulcanization vŭlˌkənəzāˈshən [key], treatment of rubber to give it certain qualities, e.g., strength, elasticity, and resistance to solvents, and to render it impervious to moderate heat and c...

siderite

(Encyclopedia)siderite kălˈĭbīt [key], a mineral, varying in color from brown, green, or gray to black and occurring in nature in massive and crystalline form. A carbonate of iron, FeCO3, it serves as an iron o...

cryolite

(Encyclopedia)cryolite or kryolite both: krīˈəlītˌ [key] [Gr.,=frost stone], mineral usually pure white or colorless but sometimes tinted in shades of pink, brown, or even black and having a luster like that o...

cobaltite

(Encyclopedia)cobaltite kōˈbôltīt, kōbôlˈtīt [key], opaque, silver-white, sometimes reddish or grayish mineral of the pyrite group, a compound of cobalt, arsenic, and sulfur, CoAsS. It occurs in crystals of...

sweetbread

(Encyclopedia)sweetbread. The thymus gland (known as throat sweetbread) and the pancreas (stomach sweetbread), especially of the calf and lamb (although beef sweetbreads are sometimes eaten), are considered delicac...

rutile

(Encyclopedia)rutile, mineral, one of three forms of titanium dioxide (TiO2; see titanium). It occurs in crystals, often in twins or rosettes, and is typically brownish red, although there are black varieties. Ruti...

clay

(Encyclopedia)clay, common name for a number of fine-grained, earthy materials that become plastic when wet. Chemically, clays are hydrous aluminum silicates, ordinarily containing impurities, e.g., potassium, sodi...

nickel

(Encyclopedia)nickel, metallic chemical element; symbol Ni; at. no. 28; at. wt. 58.6934; m.p. about 1,453℃; b.p. about 2,732℃; sp. gr. 8.902 at 25℃; valence 0, +1, +2, +3, or +4. Nickel is a hard, malleable, ...