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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...

adenine

(Encyclopedia)adenine ădˈənĭn, –nīn, –nēn [key], organic base of the purine family. Adenine combines with the sugar ribose to form adenosine, which in turn can be bonded with from one to three phosphoric ...

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...

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...

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...

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...

Franklin, Rosalind Elsie

(Encyclopedia)Franklin, Rosalind Elsie, 1920–58, English molecular biologist and chemist, grad. Newnham College, Cambridge (1941). She spent most of the war years (1942–45) working for the British Coal Utilisat...

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...

Wilkins, Maurice Hugh Frederick

(Encyclopedia)Wilkins, Maurice Hugh Frederick, 1916–2004, British biophysicist, b. New Zealand, Ph.D. Univ. of Birmingham, 1940. He conducted research at the Univ. of St. Andrews, Scotland, and at Kings College, ...