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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...

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...

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...

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. ...

adenosine triphosphate

(Encyclopedia)CE5 Adenosine triphosphate (ATP) adenosine triphosphate (ATP) ədĕnˈəsēn trīˌfŏsˈfāt [key], organic compound composed of adenine, the sugar ribose, and three phosphate groups. ATP serves ...

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...

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 ...

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...