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Dallas

(Encyclopedia)Dallas, city (2020 pop. 1,304,379), seat of Dallas co., N Tex., on the Trinity River near the junction of its three forks; inc. 1871. The third largest ...

(Encyclopedia)pearl, hard, rounded secretion formed inside the shell of certain mollusks, used as a gem. It is secreted by the epithelial cells of the mantle, a curtain of tissue between the shell and body mass, an...

chemical industry

(Encyclopedia)chemical industry, the business of using chemical reactions to turn raw materials, such as coal, oil, and salt, into a variety of products. During the 19th and 20th cent. technological advances in the...

Federal Trade Commission

(Encyclopedia)Federal Trade Commission (FTC), independent agency of the U.S. government established in 1915 and charged with keeping American business competition free and fair. The FTC has no jurisdiction over ban...

Phoenix, city, United States

(Encyclopedia)Phoenix, city (1990 pop. 983,403), state capital and seat of Maricopa co., S Ariz., on the Salt River; inc. 1881. It is the largest city in Arizona, the hub of the rich agricultural region of the Salt...

public health

(Encyclopedia)public health, field of medicine and hygiene dealing with the prevention of disease and the promotion of health by government agencies. In the United States, public health authorities are engaged in m...

algae

(Encyclopedia)algae ălˈjē [key] [plural of Lat. alga=seaweed], a large and diverse group of primarily aquatic plantlike organisms. These organisms were previously classified as a primitive subkingdom of the plan...

seaweed

(Encyclopedia)seaweed, name commonly used for the multicellular marine algae. Simpler forms, consisting of one cell (e.g., the diatom) or of a few cells, are not generally called seaweeds; these tiny plants help to...

magnesium

(Encyclopedia)magnesium măgnēˈzēəm, –zhəm [key], metallic chemical element; symbol Mg; at. no. 12; at. wt. 24.3050; m.p. about 648.8℃; b.p. about 1,090℃; sp. gr. 1.738 at 20℃; valence +2. In 1808, Sir...

cotton

(Encyclopedia)cotton, most important of the vegetable fibers, and the plant from which the fiber is harvested. Today the leading cotton states are Texas, Georgia, Mississippi, Arkansas, North Carolina, and Louisi...