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calorie

(Encyclopedia)calorie, abbr. cal, unit of heat energy in the metric system. The measurement of heat is called calorimetry. The calorie, or gram calorie, is the quantity of heat required to raise the temperature of ...

Sung

(Encyclopedia)Sung so͝ong [key], dynasty of China that ruled 960–1279. It was divided into two periods: Northern Sung (907–1126) with its capital at Kaifeng and Southern Sung (1127–1279) with its capital at ...

United States Military Academy

(Encyclopedia)United States Military Academy, at West Point, N.Y.; for training young men and women to be officers in the U.S. army; founded and opened in 1802. The original act provided that the Corps of Engineers...

ulcer

(Encyclopedia)ulcer, open sore or circumscribed erosion, usually slow to heal, on the skin or mucous membranes. It may develop as a result of injury; because of a circulatory disturbance, e.g., in varicose veins or...

radiometer

(Encyclopedia)radiometer rāˌdēŏmˈətər [key], instrument for detection or measurement of electromagnetic radiation; the term is applied in particular to devices used to measure infrared radiation. One of the ...

flood, in hydrology

(Encyclopedia)flood, inundation of land by the rise and overflow of a body of water. Floods occur most commonly when water from heavy rainfall, from melting ice and snow, or from a combination of these exceeds the ...

oil industry

(Encyclopedia)oil industry, the business of discovering oil (petroleum), extracting it from the ground, refining it into a variety of products, and distributing it to the public. The development of the oil industry...

Catherine II

(Encyclopedia)Catherine II or Catherine the Great, 1729–96, czarina of Russia (1762–96). Catherine increased the power and prestige of Russia by skillful diplomacy and by extending Russia's western boundary i...

school

(Encyclopedia)school, term commonly referring to institutions of pre-college formal education. It also properly includes colleges, universities, and many types of special training establishments (see adult educatio...

compressor

(Encyclopedia)compressor, machine that decreases the volume of air or other gas by the application of pressure. Compressor types range from the simple hand pump and the piston-equipped compressor used to inflate ti...