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Hunan

(Encyclopedia)Hunan ho͞oˈnänˈ [key] [south of the lake], province, c.80,000 sq mi (207,254 sq km), S ce...

hypertension

(Encyclopedia)hypertension or high blood pressure, elevated blood pressure resulting from an increase in the amount of blood pumped by the heart or from increased resistance to the flow of blood through the small a...

Iturbide, Agustín de

(Encyclopedia)Iturbide, Agustín de ägo͞ostēnˈ dā ēto͞orbēˈᵺā [key], 1783–1824, Mexican revolutionist, emperor of Mexico (1822–23). An officer in the royalist army, he was sympathetic to independenc...

embryo screening

(Encyclopedia)embryo screening, procedure (see genetic testing) in which a single cell is removed from an embryo two or three days after it has been conceived through in vitro fertilization and tested for genetic a...

bearing

(Encyclopedia)bearing, machine part designed to reduce friction between moving parts or to support moving loads. There are two main kinds of bearings: the antifriction type, such as the roller bearing and the ball ...

sodium

(Encyclopedia)sodium, a metallic chemical element; symbol Na [Lat. natrium]; at. no. 11; at. wt. 22.98977; m.p. 97.81℃; b.p. 892.9℃; sp. gr. 0.971 at 20℃; valence +1. Sodium is a soft, silver-white metal. Ext...

plating

(Encyclopedia)plating, application of a plate, or coat, of metal to a surface for decoration, reflection of light, protection against corrosion, or increased wearing quality. The practice is of ancient origin: gild...

Yunnan

(Encyclopedia)Yunnan or Yun-nan both: yünˈnän [key] [south of the clouds], province (2010 pop. 45,966,239), c.162,000 sq mi (419,600 sq km), SW China. It borders Myanmar on the west and Laos and Vietnam on the s...

art conservation and restoration

(Encyclopedia)art conservation and restoration, the preservation of structurally sound works of art, the halting of processes that lead to the damage of works of art, and the repair of already damaged works of art....

glass

(Encyclopedia)glass, hard substance, usually brittle and transparent, composed chiefly of silicates and an alkali fused at high temperature. Glass has become invaluable in modern architecture, illumination, elect...