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Lipmann, Fritz Albert

(Encyclopedia)Lipmann, Fritz Albert, 1899–1986, American biochemist, b. Germany, grad. Univ. of Berlin (M.D., 1922; Ph.D., 1927). He emigrated to the United States in 1939 and became a citizen in 1944. In 1941 he...

chemical equilibrium

(Encyclopedia)chemical equilibrium, state of balance in which two opposing reversible chemical reactions proceed at constant equal rates with no net change in the system. For example, when hydrogen gas, H2, and iod...

marcasite

(Encyclopedia)marcasite märˈkəsīt [key] or white iron pyrites, a mineral closely resembling and having the same chemical composition (FeS2) as pyrite. It differs from pyrite in that it is paler in color, become...

patina

(Encyclopedia)patina pătˈənə [key], coating of carbonate of copper on articles of copper or bronze, formed after long exposure to a moist atmosphere or burial in the earth. Although commonly green, patina varie...

Wacker process

(Encyclopedia)Wacker process, an industrial process for the manufacture of ethanol by oxidizing ethene. For example, bubbling ethylene and oxygen when treated by an acidified water solution of palladium and cupric ...

Dumas, Jean Baptiste André

(Encyclopedia)Dumas, Jean Baptiste André dümäˈ [key], 1800–1884, French organic chemist. He was distinguished for his researches on atomic weights, esters, vapor densities, the oxidation products of alcohols...

Meyerhof, Otto

(Encyclopedia)Meyerhof, Otto ôˈtō mīˈərhōf [key], 1884–1951, American physiologist, b. Germany, M.D. Heidelberg, 1909. He was professor at the Univ. of Kiel (1912–24) and at the Univ. of Berlin and direc...

paint

(Encyclopedia)paint, mixture of a pigment and a binding medium, usually thinned with a solvent to form a liquid vehicle. The term includes lacquer, portland cement paint, printing ink, calcimine, and whitewash. Pai...

ferrous sulfate

(Encyclopedia)ferrous sulfate or iron (II) sulfate, chemical compound, FeSO4. It is known as the monohydrate, FeSO4·H2O; the tetrahydrate, FeSO4·4H2O; the pentahydrate, FeSO4·5H2O; and the heptahydrate, FeSO4·7...

galvanizing

(Encyclopedia)galvanizing, process of coating a metal, usually iron or steel, with a protective covering of zinc. Galvanized iron is prepared either by dipping iron, from which rust has been removed by the action o...