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Charles III, king of Spain, and of Naples and Sicily

(Encyclopedia)Charles III, 1716–88, king of Spain (1759–88) and of Naples and Sicily (1735–59), son of Philip V and Elizabeth Farnese. Recognized as duke of Parma and Piacenza in 1731, he relinquished the duc...

Tarde, Gabriel de

(Encyclopedia)Tarde, Gabriel de gäbrēĕlˈ də tärd [key], 1843–1904, French sociologist and criminologist. During his years of public service as a magistrate, he became interested in the psychosocial bases of...

glutamine

(Encyclopedia)CE5 glutamine glo͞oˈtəmēn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer occurs in mammalian protein. Its structure is identical t...

Graham, Thomas

(Encyclopedia)Graham, Thomas, 1805–69, Scottish chemist, best known for research in diffusion in both gases and liquids that led to his formulation of Graham's law. His discovery that certain substances (e.g., gl...

amide

(Encyclopedia)amide ămˈīd [key], organic compound formed by reaction of an acid chloride, acid anhydride, or ester with an amine. Under strong acidic conditions an amide can be hydrolyzed to yield an amine and a...

talus

(Encyclopedia)talus tāˈləs [key], deposit of rock fragments detached from cliffs or mountain slopes by weathering and piled up at their bases. A talus is a common geologic feature in regions of high cliffs. The ...

palladium, chemical element

(Encyclopedia)palladium [Gr. Pallas, goddess of wisdom], metallic chemical element; symbol Pd; at. no. 46; at. wt. 106.42; m.p. 1,554℃; b.p. 2,970℃; sp. gr. 12.02 at 20℃; valence +2, +3, or +4. Palladium is a...

polystyrene

(Encyclopedia)polystyrene pŏlˌēstīˈrēn [key], widely used plastic; it is a polymer of styrene. Polystyrene is a colorless, transparent thermoplastic that softens slightly above 100℃ (212℉) and becomes a v...

nitrogen cycle

(Encyclopedia)CE5 Nitrogen cycle nitrogen cycle, the continuous flow of nitrogen through the biosphere by the processes of nitrogen fixation, ammonification (decay), nitrification, and denitrification. Nitrogen...

grease

(Encyclopedia)grease, mixture of lubricant and thickener. It is used to reduce friction between surfaces from which oils would leak away or cause damage by dripping, or where lubrication must be assured for extende...