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sodium sulfate

(Encyclopedia)sodium sulfate, chemical compound, Na2SO4. It is a white, orthorhombic crystalline compound at ordinary temperatures; above 100℃ it assumes a monoclinic structure, and above about 250℃ it assumes ...

pickle

(Encyclopedia)pickle, general term for fruits or vegetables preserved in vinegar or brine, usually with spices or sugar or both. Vegetables commonly pickled include the beet, cabbage, cauliflower, cucumber, olive, ...

titration

(Encyclopedia)titration tītrāˈshən [key], gradual addition of an acidic solution to a basic solution or vice versa (see acids and bases); titrations are used to determine the concentration of acids or bases in ...

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...

lysine

(Encyclopedia)CE5 lysine līˈsēn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essential amino...

peptide

(Encyclopedia)peptide, organic compound composed of amino acids linked together chemically by peptide bonds. The peptide bond always involves a single covalent link between the α-carboxyl (oxygen-bearing carbon) o...

colchicine

(Encyclopedia)colchicine kŏlˈchəsēnˌ [key], alkaloid extracted from plants of the genus Colchicum and especially from the corms of the autumn crocus, Colchicum autumnale (see meadow saffron). The metabolic eff...

acetaldehyde

(Encyclopedia)acetaldehyde ĕthˈənălˌ [key], CH3CHO, colorless liquid aldehyde, sometimes simply called aldehyde. It melts at −123℃, boils at 20.8℃, and is soluble in water and ethanol. It is formed by th...

phosgene

(Encyclopedia)phosgene fŏsˈjēn [key], colorless poison gas, first used during World War I by the Germans (1915). When dispersed in air, the gas has the odor of new-mowed hay. The gas is highly toxic; when inhale...

printed circuit

(Encyclopedia)printed circuit, electric circuit in which the conducting paths connecting circuit components are affixed to a flat, insulating base board. The base is typically of plastic, glass, ceramic, or some ot...