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salicylate

(Encyclopedia)salicylate səlĭsˈəlātˌ [key], any of a group of analgesics, or painkilling drugs, that are derivatives of salicylic acid. The best known is acetylsalicylic acid, or aspirin. Now often made synth...

tungsten

(Encyclopedia)tungsten tŭngˈstən [key] [Swed.,=heavy stone], metallic chemical element; symbol W; at. no. 74; at. wt. 183.84; m.p. about 3,410℃; b.p. 5,660℃; sp. gr. 19.3 at 20℃; valence +2, +3, +4, +5, or...

recombination

(Encyclopedia)recombination, process of “shuffling” of genes by which new combinations can be generated. In recombination through sexual reproduction, the offspring's complete set of genes differs from that of ...

protein

(Encyclopedia)protein, any of the group of highly complex organic compounds found in all living cells and comprising the most abundant class of all biological molecules. Protein comprises approximately 50% of cellu...

Lydd

(Encyclopedia)Lydd lĭd [key], town (1991 pop. 4,721), Kent, SE England. A military training center, Lydd gave its name to lyddite (picric acid), an explosive that was tested at the military camp there in 1888. Lyd...

Prout, William

(Encyclopedia)Prout, William, 1785–1850, English chemist and physician. Prout's hypothesis, advanced in 1815–16, suggested that atomic weights of elements are multiples of that of hydrogen and that elements are...

tartar

(Encyclopedia)tartar or argol ärˈgəl [key], impure potassium hydrogen tartrate deposited as a crust in fermenting vessels during wine making. When purified, it yields cream of tartar. Tartar is the chief natural...

zinc sulfate

(Encyclopedia)zinc sulfate, chemical compound ZnSO4, a very water soluble, transparent, colorless, crystalline compound. It is commonly used as the heptahydrate, ZnSO4·7H2O, and is commonly called white vitriol; i...

atropine

(Encyclopedia)atropine ătˈrəpēn, –pĭn [key], alkaloid drug derived from belladonna and other plants of the family Solanaceae (nightshade family). Available either as the tincture or extract of belladonna, or...

leucine

(Encyclopedia)CE5 leucine lo͞oˈsēn [key], organic compund, one of the 20 amino acids commonly found in animal proteins. Only the l-stereooisomer appears in mammalian protein. It is one of several essential am...