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saturation, of an organic compound

(Encyclopedia)saturation, of an organic compound, condition occurring when its molecules contain no double or triple bonds and thus cannot undergo addition reactions. For example, ethane (H3C–CH3) is a saturated ...

mineral, dietary

(Encyclopedia)mineral, dietary, any of a group of inorganic elements that are essential to humans and animals for normal body function. In nutrition, minerals are those elements for which the body's requirement is ...

asbestos, mineral

(Encyclopedia)asbestos, common name for any of a variety of silicate minerals within the amphibole and serpentine groups that are fibrous in structure and more or less resistant to acid and fire. Chrysotile asbesto...

seal, stamp

(Encyclopedia)seal, stamp made from a die or matrix of metal, a gem, or other hard substance that yields an impression on wax or other soft substance. The use of seals is very ancient, examples of great antiquity o...

Côte-d'Or

(Encyclopedia)Côte-d'Or kōt-dôr [key], department, E France, largely in Burgundy, partly in Champagne. ...

Sabatier, Paul, French organic chemist

(Encyclopedia)Sabatier, Paul, 1854–1941, French organic chemist, D.Sc. Collège de France, 1880. He joined the faculty at the Univ. of Toulouse in 1882 and taught there until he retired in 1930. Sabatier was a co...

pitch, substance

(Encyclopedia)pitch: see tar and pitch.

spinel

(Encyclopedia)spinel, magnesium aluminum oxide, MgAl2O4, a mineral crystallizing in the isometric system, usually as octahedrons. It occurs as an accessory mineral in basic igneous rocks, in aluminum-rich metamorph...

Val d'Or

(Encyclopedia)Val d'Or väl dôr [key], town (1991 pop. 23,842), SW Que., Canada, SE of Rouyn-Noranda. It is a mining center. Gold was discovered in the region in 1909; copper, zinc, lead, and molybdenum are also m...

tourmaline

(Encyclopedia)tourmaline to͝orˈməlĭn, –lēn [key], complex borosilicate mineral with varying amounts of aluminum, iron, magnesium, sodium, lithium, potassium, and sometimes other elements, used as a gem. It o...