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corrosion

(Encyclopedia)corrosion, atmospheric oxidation of metals (see oxidation and reduction). By far the most important form of corrosion is the rusting of iron. Rusting is essentially a process of oxidation in which iro...

Northwich

(Encyclopedia)Northwich nôrthˈwĭch [key], town (1991 pop. 32,664), Cheshire West and Chester, W central England, at the confluence of the Weaver and Dane rivers. Northwich was once the center of England's salt p...

Avery Island

(Encyclopedia)Avery Island, salt dome, 163 ft (50 m) high and 2 mi (3.2 km) in diameter, S La., in an area of sea marshes and swamps. A corporation controlled by the Avery and McIlhenny families owns the island. Ho...

ligand

(Encyclopedia)ligand lĭgˈənd [key], charged or uncharged molecule with one or more unshared pairs of electrons that can attach to a central metallic atom or ion to form an aggregate known as a complex ion (see c...

lipoprotein

(Encyclopedia)lipoprotein lĭpˌəprōˈtēn [key], any organic compound that is composed of both protein and the various fatty substances classed as lipids, including fatty acids and steroids such as cholesterol. ...

samarium

(Encyclopedia)samarium səmârˈēəm [key], metallic chemical element; symbol Sm; at. no. 62; at. wt. 150.36; m.p. 1,072℃; b.p. 1,791℃; sp. gr. 7.54 at 20℃; valence +2 or +3. Samarium is a lustrous silver-wh...

fertilizer

(Encyclopedia)fertilizer, organic or inorganic material containing one or more of the nutrients—mainly nitrogen, phosphorus, and potassium, and other essential elements required for plant growth. Added to the soi...

alumina

(Encyclopedia)alumina əlo͞oˈmĭnə [key] or aluminum oxide, Al2O3, chemical compound with m.p. about 2,000℃ and sp. gr. about 4.0. It is insoluble in water and organic liquids and very slightly soluble in stro...

sulfa drug

(Encyclopedia)sulfa drug, any of a class of synthetic chemical substances derived from sulfanilamide, or para-aminobenzenesulfonamide. Sulfa drugs are used to treat bacterial infections, although they have largely ...

Brenner, Sydney

(Encyclopedia)Brenner, Sydney, 1927–2019, British molecular biologist, Ph.D. Oxford, 1954. He was director of the MRC Laboratory of Molecular Biology in Cambridge, England (1979–86), and director of the MRC Mol...