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tung oil

(Encyclopedia)tung oil, oil obtained from the seeds of a tropical tree, the tung tree (Aleurites fordii) of the spurge family, and from seeds of some related species, all from Indomalesia or W Pacifica. It is known...

valine

(Encyclopedia)CE5 valine vălˈēn [key], organic compound, one of the 22 α-amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essential am...

Sanger, Frederick

(Encyclopedia)Sanger, Frederick săngˈər [key], 1918–2013, British biochemist, grad. Cambridge (B.A., 1939; Ph.D., 1943). He continued his research at Cambridge after 1943. He won the 1958 Nobel Prize in Chemis...

cashew

(Encyclopedia)cashew kăshˈo͞o, kəsho͞oˈ [key], tropical American tree (Anacardium occidentale) of the family Anacardiaceae (sumac family), valued chiefly for the cashew nut of commerce. The tree's acrid sap i...

protonation

(Encyclopedia)protonation prōˈtənāˌshən [key], in chemistry, addition of a proton to an atom, molecule, or ion. The proton is the nucleus of the hydrogen atom; the positive hydrogen ion, H+, consists of a sin...

azalea

(Encyclopedia)azalea əzālˈyə [key] [Gr.,=dry], any species of the genus Rhododendron, North American and Asian shrubs of the family Ericaceae (heath family) that are distinguished by the usually deciduous leave...

ether, in chemistry

(Encyclopedia)CE5 Ethers ether, any of a number of organic compounds whose molecules contain two hydrocarbon groups joined by single bonds to an oxygen atom. The most common of these compounds is ethyl ether, C...

lactose

(Encyclopedia)lactose lăkˈtōs [key] or milk sugar, white crystalline disaccharide (see carbohydrate). It has the same empirical formula (C12H22O11) as sucrose (cane sugar) and maltose but differs from both in st...

bead test

(Encyclopedia)bead test, test used in the identification of certain metals. Some metallic ions that cannot be identified by a flame test are identified by a bead test. The test can also be used to confirm the resul...

carbon cycle

(Encyclopedia)CE5 Carbon cycle carbon cycle, in biology, the exchange of carbon between living organisms and the nonliving environment. Inorganic carbon dioxide in the atmosphere is converted by plants into sim...