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buffer

(Encyclopedia)buffer, solution that can keep its relative acidity or alkalinity constant, i.e., keep its pH constant, despite the addition of strong acids or strong bases. Buffer solutions are frequently solutions ...

ester

(Encyclopedia)CE5 Esters ester, any one of a group of organic compounds with general formula RCO2R′ (where R and R′ are alkyl groups or aryl groups) that are formed by the reaction between an alcohol and an...

Kölreuter, Joseph Gottlieb

(Encyclopedia)Kölreuter or Koelreuter, Joseph Gottlieb both: yōˈzĕf gôtˈlēp kölˈroiˌtər [key], 1733–1806, German botanist. In 1764 he became professor of natural history and director of the botanical g...

Hosanna

(Encyclopedia)Hosanna hōzănˈə [key] [Heb.,=save now; Psalm 118], an intensified imperative, a cry, addressed to God, particularly used in the Feast of Tabernacles, when prayers for rain were offered. In the New...

Rondônia

(Encyclopedia)Rondônia ro͝ondôˈnyə [key], state (1996 pop. 1,132,692), 93,839 sq mi (243,043 sq km), NW Brazil, on the border with Bolivia. Pôrto Velho is the capital. Rain forests still cover much of the sta...

Valmy

(Encyclopedia)Valmy välmēˈ [key], village (1993 est. pop. 293), Marne dept., NE France, in the Argonne region. The “cannonade of Valmy,” a Franco-Prussian artillery skirmish, was fought near there on Sept. 2...

cryolite

(Encyclopedia)cryolite or kryolite both: krīˈəlītˌ [key] [Gr.,=frost stone], mineral usually pure white or colorless but sometimes tinted in shades of pink, brown, or even black and having a luster like that o...

gastric juice

(Encyclopedia)gastric juice, thin, strongly acidic (pH varying from 1 to 3), almost colorless liquid secreted by the glands in the lining of the stomach. Its essential constituents are the digestive enzymes pepsin ...

coenzyme

(Encyclopedia)coenzyme kō-ĕnˈzīm [key], any one of a group of relatively small organic molecules required for the catalytic function of certain enzymes. A coenzyme may either be attached by covalent bonds to a ...

forest

(Encyclopedia)forest, a dense growth of trees, together with other plants, covering a large area of land. The science concerned with the study, preservation, and management of forests is forestry. A forest is an ec...