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bone meal

(Encyclopedia)bone meal, finely ground bone used as a fertilizer for its content of phosphate and nitrogen (about 23%–30% available phosphate and 2%–4% nitrogen); it is an expensive form of phosphoric acid when...

antiseptic

(Encyclopedia)antiseptic, agent that kills or inhibits the growth of microorganisms on the external surfaces of the body. Antiseptics should generally be distinguished from drugs such as antibiotics that destroy mi...

glucagon

(Encyclopedia)glucagon glo͞oˈkəgŏn [key], hormone secreted by the α cells of the islets of Langerhans, specific groups of cells in the pancreas. It tends to counteract the action of insulin, i.e., it raises th...

jelly and jam

(Encyclopedia)jelly and jam, gelatinous, sweet food prepared by preserving fresh fruits. Since most fresh fruits contain about 80% water and from 10% to 15% sugar, they are subject to fermentation. They may be pres...

phenol

(Encyclopedia)phenol fēˈnōl [key], C6H5OH, a colorless, crystalline solid that melts at about 41℃, boils at 182℃, and is soluble in ethanol and ether and somewhat soluble in water. An aromatic alcohol, it ex...

sweetener, artificial

(Encyclopedia)sweetener, artificial, substance used as a low-calorie sugar substitute. Saccharin, cyclamates, and aspartame have been the most commonly used artificial sweeteners. Saccharin, a coal-tar derivative t...

cream of tartar

(Encyclopedia)cream of tartar, white crystalline powder. Chemically it is potassium hydrogen tartrate, KC4H5O6, the acidic potassium salt of tartaric acid. It is used as the leavening agent in baking powders. An im...

kinetin

(Encyclopedia)kinetin kīˈnətĭn [key], one of a group of chemically similar plant hormones, the cytokinins, that promote cell division. In some instances kinetin acts together with another hormone, indoleacetic ...

sodium benzoate

(Encyclopedia)sodium benzoate or benzoate of soda, chemical compound, C6H5CO2Na, colorless or white crystalline, aromatic compound; the sodium salt of benzoic acid. It is soluble in water and is used as a preservat...

Roebuck, John

(Encyclopedia)Roebuck, John, 1718–94, English physician, chemist, and inventor. He acted as a chemical consultant to local industries in Birmingham and invented the lead chamber process of manufacturing sulfuric ...