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dysprosium

(Encyclopedia)dysprosium dĭsprōˈzēəm [key] [Gr.,=hard to get at], metallic chemical element; symbol Dy; at. no. 66; at. wt. 162.500; m.p. 1,412℃; b.p. 2,562℃; sp. gr. 8.54 at 25℃; valence+3. Dysprosium i...

cloud

(Encyclopedia)CE5 Approximate heights of some types of clouds cloud, aggregation of minute particles of water or ice suspended in the air. Cloudiness (or proportion of the sky covered by any form of cloud),...

Haig, Douglas Haig, 1st Earl

(Encyclopedia)Haig, Douglas Haig, 1st Earl, 1861–1928, British field marshal. He saw active service in Sudan (1898) and in the South African War (1899–1902) and upon the outbreak of World War I (1914) was given...

calendering

(Encyclopedia)calendering, a finishing process by which paper, plastics, rubber, or textiles are pressed into sheets and smoothed, glazed, polished, or given a moiré or embossed surface. The material is passed thr...

sawmill

(Encyclopedia)sawmill, installation or facility in which cut logs are sawed into standard-sized boards and timbers. The saws used in such an installation are generally of three types: the circular saw, which consis...

derecho

(Encyclopedia)derecho dərāˈchō [key], a long-lived windstorm over a wide expanse that is associated with a line of rapidly moving thunderstorms or showers. The winds in a derecho generally exceed 57 mph (92 kph...

infrared astronomy

(Encyclopedia)infrared astronomy, study of celestial objects by means of the infrared radiation they emit, in the wavelength range from about 1 micrometer to about 1 millimeter. All objects, from trees and building...

fire fighting

(Encyclopedia)fire fighting, the use of strategy, personnel, and apparatus to extinguish, to confine, or to escape from fire. Ancient Rome is known to have had a fire department consisting by the 1st cent. of app...

pump

(Encyclopedia)pump, device to lift, transfer, or increase the pressure of a fluid (gas or liquid) or to create a vacuum in an enclosed space by the removal of a gas (see vacuum pumps under vacuum). The centrifugal ...

terrace

(Encyclopedia)terrace, a level field built on top of a hillslope into the floor of a deep valley to improve cultivation of crops. Terracing uses the runoff from the hill to increase soil retentiveness and arability...