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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 ...

pyrogallol

(Encyclopedia)pyrogallol –ĭk [key], C6H6O3, white, crystalline, aromatic compound with a biting taste; it is poisonous. It melts at 133℃ and boils at 309℃. In alkaline solution it is an active reducing agent...

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...

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...

Albert II, king of the Belgians

(Encyclopedia)Albert II, 1934–, king of the Belgians (1993–2013), the younger son of Leopold III. He married Donna Paola Ruffo de Calabria in 1959; they have three children. Albert became king when Baudouin, hi...

Eve, in genetics

(Encyclopedia)Eve, in genetics, popular term for a theoretical female ancestor of all living people, also known as Mitochondrial Eve. In 1987 biochemist Allan C. Wilson proposed that all living human beings had inh...

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 ...

oxide

(Encyclopedia)oxide, chemical compound containing oxygen and one other chemical element. Oxides are widely and abundantly distributed in nature. Water is the oxide of hydrogen. Silicon dioxide is the major componen...

Ciechanover, Aaron

(Encyclopedia)Ciechanover, Aaron, 1947–, Israeli biochemist, M.D. Hebrew Univ.–Hadassah Medical School, Jerusalem, 1974; D.Sc. Technion (Israel Institute of Technology), Haifa, 1982. He has been on the faculty ...