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Crofton, Sir John Wenman

(Encyclopedia)Crofton, Sir John Wenman, 1912–2009, British physician, b. Dublin. He served in the British medical corps during World War II and during 1946–52 was part of a research team studying the effects of...

cyanide process

(Encyclopedia)cyanide process or cyanidation, method for extracting gold from its ore. The ore is first finely ground and may be concentrated by flotation; if it contains certain impurities, it may be roasted. It i...

alanine

(Encyclopedia)CE5 alanine ălˈənēnˌ [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer participates in the biosynthesis of proteins (see stereochemi...

Roethke, Theodore

(Encyclopedia)Roethke, Theodore rĕtˈkə [key], 1908–63, American poet, b. Saginaw, Mich., educated at the Univ. of Michigan and Harvard. A poet of the Midwest, Roethke combined a love of the land with his visio...

rosin

(Encyclopedia)rosin or colophony, hard, brittle, translucent resin, obtained as a solid residue from crude turpentine. Usually pale yellow or amber, its color may vary from brownish-black to transparent depending o...

pyrimidine

(Encyclopedia)CE5 Pyrimidines found in deoxyribonucleic acid (DNA) pyrimidine pīrĭmˈĭdēnˌ [key], type of organic base found in certain coenzymes and in the nucleic acids of plant and animal tissue. The th...

tamarind

(Encyclopedia)tamarind tămˈərĭnd [key], tropical ornamental evergreen tree (Tamarindus indica) of the family Leguminosae (pulse family), native to Africa and probably to Asia, but now widely grown in the tropic...

bromide

(Encyclopedia)bromide, any of a group of compounds that contain bromine and a more electropositive element or radical. Bromides are formed by the reaction of bromine or a bromide with another substance; they are wi...

cellophane

(Encyclopedia)cellophane, thin, transparent sheet or tube of regenerated cellulose. Cellophane is used in packaging and as a membrane for dialysis. It is sometimes dyed and can be moisture-proofed by a thin coating...

Cannizzaro, Stanislao

(Encyclopedia)Cannizzaro, Stanislao stänēsläˈō kän-nēt-tsäˈrō [key], 1826–1910, Italian chemist. From 1861 he was professor at Palermo and from 1871 at Rome, where he was also a member of the senate and...