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actinometer

(Encyclopedia)actinometer ăkˌtənŏmˈətər [key], instrument used to measure the heating power of radiation. Actinometers are used chiefly in meteorology to measure solar radiation as transmitted directly by th...

Termez

(Encyclopedia)Termez tyĭrmyĕsˈ [key], city (1991 pop. 99,000), capital of Surkhandaryo region, S Uzbekistan, a port on the Amu Darya River, near the Afghanistan border. It is the center of an agricultural region...

cyclosis

(Encyclopedia)cyclosis sīklōˈsĭs [key], streaming of cytoplasm within a living cell without deformation of the external cell membrane. In some plant cells there is a rapid rotatory cytoplasmic movement, which i...

Anderson, Philip Warren

(Encyclopedia)Anderson, Philip Warren, 1923–2020, American physicist, b. Indianapolis, Ind., Ph.D. Harvard, 1949. After graduation he worked at Bell Laboratories until 1984. From 1967 he also was on the faculty a...

pasteurization

(Encyclopedia)pasteurization păsˌcho͝orĭzāˈshən, –rīzāˈshən [key], partial sterilization of liquids such as milk, orange juice, wine, and beer, as well as cheese, to destroy disease-causing and other u...

ammonium nitrate

(Encyclopedia)ammonium nitrate, chemical compound, NH4NO3, that exists as colorless, rhombohedral crystals at room temperature but changes to monoclinic crystals when heated above 32℃. It is extremely soluble in ...

Hertzsprung, Ejnar

(Encyclopedia)Hertzsprung, Ejnar īˈnär hĕrtsˈspro͞ong [key], 1873–1967, Danish astronomer. Although trained as a chemical engineer, Hertzsprung made his career in astronomy, specializing in exacting photogr...

Hot Springs National Park

(Encyclopedia)Hot Springs National Park, 5,549 acres (2,247 hectares), W central Ark.; est. 1921; nearly surrounded by the city of Hot Springs. Visited by Spanish explorer Hernando De Soto in 1541, the springs, lon...

phonon

(Encyclopedia)phonon fōˈnŏn [key], quantum of vibrational energy. The atoms of any crystal are in a state of vibration, their average kinetic energy being measured by the absolute temperature of the crystal. In ...

diving, deep-sea

(Encyclopedia)diving, deep-sea, act of descending into deep water, generally with some form of breathing apparatus, and remaining there for an extended period. It is used in fishing for sponges, coral, and pearls; ...