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carotene

(Encyclopedia)carotene kârˈətēnˌ [key], long-chained, unsaturated hydrocarbon found as a pigment in many higher plants, particularly carrots, sweet potatoes, and leafy vegetables. Carotene is thought to assist...

Calonne, Charles Alexandre de

(Encyclopedia)Calonne, Charles Alexandre de shärl älĕksäNˈdrə də kälōnˈ [key], 1734–1802, French statesman, controller general of finances (1783–87). Faced with a huge public debt and a steadily deter...

holmium

(Encyclopedia)holmium hōlˈmēəm [key] [Lat.,=Stockholm], metallic chemical element; symbol Ho; at. no. 67; at. wt. 164.93032; m.p. about 1,474℃; b.p. about 2,425℃; sp. gr. 8.78 at 25℃; valence +3. Holmium ...

Green, Duff

(Encyclopedia)Green, Duff, 1791–1875, American journalist and politician, b. Woodford co., Ky. After service in the War of 1812, he settled in Missouri, where he became (1824) editor of the St. Louis Enquirer. He...

parvovirus

(Encyclopedia)parvovirus pärˌvōvīˈrəs [key], any of several small DNA viruses that cause several diseases in animals, including humans. In humans, parvoviruses cause fifth disease, or erythema infectiosum, an...

glycol

(Encyclopedia)glycol glīˈkōl [key], dihydric alcohol in which the two hydroxyl groups are bonded to different carbon atoms; the general formula for a glycol is (CH2)n(OH)2. The most important glycol is the simpl...

antioxidant

(Encyclopedia)antioxidant, substance that prevents or slows the breakdown of another substance by oxygen. Synthetic and natural antioxidants are used to slow the deterioration of gasoline and rubber, and such antio...

indium

(Encyclopedia)indium ĭnˈdēəm [key], a metallic chemical element; symbol In; at. no. 49; at. wt. 114.818; m.p. 156.6℃; b.p. about 2,080℃; sp. gr. 7.31 at 20℃; valence +1, +2, or +3. Indium is a soft, malle...

tempera

(Encyclopedia)tempera tĕmˈpərə [key], painting method in which finely ground pigment is mixed with a solidifying base such as albumen, fig sap, or thin glue. When used in mural painting it is also known as fres...

biochemistry

(Encyclopedia)biochemistry, science concerned chiefly with the chemistry of biological processes; it attempts to utilize the tools and concepts of chemistry, particularly organic and physical chemistry, for elucida...