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balsam

(Encyclopedia)balsam bôlˈsəm [key], fragrant resin obtained from various trees. The true balsams are semisolid and insoluble in water, but they are soluble in alcohol and partly so in hydrocarbons. They contain ...

sodium bicarbonate

(Encyclopedia)sodium bicarbonate or sodium hydrogen carbonate, chemical compound, NaHCO3, a white crystalline or granular powder, commonly known as bicarbonate of soda or baking soda. It is soluble in water and ver...

aging

(Encyclopedia)aging, in biology, cumulative changes in an organism, organ, tissue, or cell leading to a decrease in functional capacity. In humans, aging is associated with degenerative changes in the skin, bones, ...

charcoal

(Encyclopedia)charcoal, substance obtained by partial burning or carbonization (destructive distillation) of organic material. It is largely pure carbon. The entry of air during the carbonization process is control...

iodine

(Encyclopedia)iodine īˈədīn, –dĭn [key] [Gr.,=violet], nonmetallic chemical element; symbol I; at. no. 53; at. wt. 126.90447; m.p. 113.5℃; b.p. 184.35℃; sp. gr. 4.93 at 20℃; valence −1, +1, +3, +5, o...

ozone layer

(Encyclopedia)ozone layer or ozonosphere, region of the stratosphere containing relatively high concentrations of ozone, located at altitudes of 12–30 mi (19–48 km) above the earth's surface. Ozone in the ozone...

battery, electric

(Encyclopedia)CE5 Lead storage cell: At the lead-dioxide electrode, electrons from the circuit combine with lead dioxide and sulfuric acid to form lead sulfate and water. At the spongy-lead electrode, lead react...

respiration

(Encyclopedia)CE5 Respiratory system respiration, process by which an organism exchanges gases with its environment. The term now refers to the overall process by which oxygen is abstracted from air and is tran...

eating disorders

(Encyclopedia)eating disorders, in psychology, disorders in eating patterns that comprise four categories: anorexia nervosa, bulimia, rumination disorder, and pica. Anorexia nervosa is characterized by self-starvat...

ebony

(Encyclopedia)ebony, common name for members of the Ebenaceae, a family of trees and shrubs widely distributed in warmer climates and in the tropics. The principal genus, Diospyros, includes both ebony and persimmo...