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cautery

(Encyclopedia)cautery, searing or destruction of living animal tissue by use of heat or caustic chemicals. In the past, cauterization of open wounds, even those following amputation of a limb, was performed with ho...

prosthetic group

(Encyclopedia)prosthetic group, non-amino acid portions of certain protein molecules. The key part of the prosthetic group may be either organic (such as a vitamin) or inorganic (such as a metal) and is usually req...

isomer

(Encyclopedia)isomer īˈsəmər [key], in chemistry, one of two or more compounds having the same molecular formula but different structures (arrangements of atoms in the molecule). Isomerism is the occurrence of ...

Dacron

(Encyclopedia)Dacron dāˈkrŏn, dăkˈrŏn [key], trademark for a polyester fiber. Dacron is a condensation polymer obtained from ethylene glycol and terephthalic acid. Its properties include high tensile strength...

ammonium sulfate

(Encyclopedia)ammonium sulfate, chemical compound, (NH4)2SO4, a colorless-to-gray, rhombohedral crystalline substance that occurs in nature as the mineral mascagnite. It is soluble in water and insoluble in alcohol...

Ochoa, Severo

(Encyclopedia)Ochoa, Severo sāvāˈrō ōchōˈä [key], 1905–93, American biochemist and educator, b. Spain, M.D. Univ. of Madrid, 1929. After teaching at the universities of Madrid, Heidelberg, and Oxford, he ...

Woodward, Robert Burns

(Encyclopedia)Woodward, Robert Burns, 1917–80, American chemist and educator, b. Boston, grad. Massachusetts Institute of Technology (S.B., 1936; Ph.D., 1937). He taught at Harvard from 1938, becoming Donner prof...

Berthollet, Claude Louis, Comte

(Encyclopedia)Berthollet, Claude Louis, Comte klōd lwē, kôNt bĕrtōlāˈ [key], 1748–1822, French chemist. His contributions to chemistry include the analysis of ammonia and prussic acid and the discovery of ...

Sörensen, Sören Peter Lauritz

(Encyclopedia)Sörensen, Sören Peter Lauritz söˈrən pēˈtər louˈrēts söˈrənsən [key], 1868–1939, Danish biochemist. In 1899 he received a Ph.D. degree in Copenhagen. Sörensen was director of chemistr...

ramontchi

(Encyclopedia)ramontchi, small tree or shrub (Flacourtia indica) belonging to the family Flacourtiaceae. It is cultivated in S Asia and in other tropical regions for its large edible berries. Dark purple to black i...