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Concordat of 1801

(Encyclopedia)Concordat of 1801, agreement between Napoleon Bonaparte and Pope Pius VII that reestablished the Roman Catholic Church in France. Napoleon took the initiative in negotiating this agreement; he recogni...

sediment

(Encyclopedia)sediment, mineral or organic particles that are deposited by the action of wind, water, or glacial ice. These sediments can eventually form sedimentary rocks (see rock). Sediments form sedimentary ...

ozone

(Encyclopedia)ozone ōˈzōn [key], an allotropic form of the chemical element oxygen (see allotropy). Pure ozone is an unstable, faintly bluish gas with a characteristic fresh, penetrating odor. The gas has a dens...

Porifera

(Encyclopedia)CE5 A. Canal systems of the three morphological types of sponges B. Internal anatomy of an asconoid sponge, representative of the phylum Porifera Porifera pōrĭfˈərə [key] [Lat.,=pore bearer],...

methyl

(Encyclopedia)methyl mĕthˈəl [key], CH3, organic free radical or alkyl group derived from methane by the removal of one hydrogen atom. ...

fusel oil

(Encyclopedia)fusel oil fyo͞oˈzəl [key], oily, colorless liquid with a disagreeable odor and taste. It is a mixture of alcohols (largely amyl alcohols) and fatty acids, formed during the alcoholic fermentation o...

Pelletier, Pierre Joseph

(Encyclopedia)Pelletier, Pierre Joseph pyĕr zhôzĕfˈ pĕlətyāˈ [key], 1788–1842, French chemist. With J. B. Caventou, he was cofounder of alkaloid chemistry and codiscoverer of quinine, strychnine, brucine,...

phenyl

(Encyclopedia)phenyl fĕnˈəl [key], C6H5, organic free radical or alkyl group derived from benzene by removing one hydrogen atom. ...

cyanide

(Encyclopedia)cyanide sīˈənīdˌ [key], chemical compound containing the cyano group, –CN. Cyanides are salts or esters of hydrogen cyanide (hydrocyanic acid, HCN) formed by replacing the hydrogen with a metal...

eutrophication

(Encyclopedia)eutrophication yo͞otrōˌfĭkāˈshən [key], aging of a lake by biological enrichment of its water. In a young lake the water is cold and clear, supporting little life. With time, streams draining i...