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zinc

(Encyclopedia)zinc, metallic chemical element; symbol Zn; at. no. 30; at. wt. 65.38; m.p. 419.58℃; b.p. 907℃; sp. gr. 7.133 at 25℃; valence +2. Zinc is a lustrous bluish-white metal. It is found in Group 12 o...

protein

(Encyclopedia)protein, any of the group of highly complex organic compounds found in all living cells and comprising the most abundant class of all biological molecules. Protein comprises approximately 50% of cellu...

DNA fingerprinting

(Encyclopedia)DNA fingerprinting or DNA profiling, any of several similar techniques for analyzing and comparing DNA from separate sources, used especially in law enforcement to identify suspects from hair, blood, ...

Kansas-Nebraska Act

(Encyclopedia)Kansas-Nebraska Act, bill that became law on May 30, 1854, by which the U.S. Congress established the territories of Kansas and Nebraska. By 1854 the organization of the vast Platte and Kansas river c...

beryllium

(Encyclopedia)beryllium bərĭlˈēəm [key] [from beryl ], metallic chemical element; symbol Be; at. no. 4; at. wt. 9.01218; m.p. about 1,278℃; b.p. 2,970℃ (estimated); sp. gr. 1.85 at 20℃; valence +2. Ber...

radar

(Encyclopedia)radar, system or technique for detecting the position, movement, and nature of a remote object by means of radio waves reflected from its surface. Although most radar units use microwave frequencies, ...

interior decoration

(Encyclopedia)interior decoration, adornment of the interior of a building, public or domestic, comprising interior architecture, finishing, and furnishings. Asian and classical cultures used the decorative arts to...

Bengal

(Encyclopedia)Bengal bĕng-gôlˈ, bĕn– [key], region, 77,442 sq mi (200,575 sq km), E India and Bangladesh, on the Bay of Bengal. The inland section is mountainous, with peaks up to 12,000 ft (3,660 m) high in ...

thorium

(Encyclopedia)thorium thôrˈēəm [key] [from Thor], radioactive chemical element; symbol Th; at. no. 90; mass number of most stable isotope 232; m.p. about 1,750℃; b.p. about 4,790℃; sp. gr. 11.7 at 20℃; va...

chromosphere

(Encyclopedia)chromosphere krōˈməsfērˌ [key] [Gr.,=color sphere], layer of rarefied, transparent gases in the solar atmosphere; it measures 6,000 mi (9,700 km) in thickness and lies between the photosphere (th...