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clothes moth

(Encyclopedia)clothes moth, name for several species of moths of the family Tineidae, whose larvae feed on wool, furs, feathers, upholstery, and a variety of animal products. Clothes moths are of Old World origin. ...

fog

(Encyclopedia)fog, aggregation of water droplets or ice crystals immediately above the surface of the earth (i.e., a cloud near the ground). A light or thin fog is usually called a mist. Fog may occur when the mois...

tempering

(Encyclopedia)tempering, process involving slow and moderate heating to increase the hardness and toughness of metals that have undergone previous heat treatment. Metals are usually hardened (see hardening) by bein...

welding

(Encyclopedia)welding, process for joining separate pieces of metal in a continuous metallic bond. Cold-pressure welding is accomplished by the application of high pressure at room temperature; forge welding (forgi...

van der Waals, Johannes Diderik

(Encyclopedia)van der Waals, Johannes Diderik yōhäˈnəs dēˈdərĭk vän dər väls [key], 1837–1923, Dutch physicist. It had been known for some time that the behavior of real gases differs from that of an i...

trichina

(Encyclopedia)trichina trĭkīˈnə [key], common name for species of roundworm of the phylum Nematoda. The species Trichinella spiralis is an important parasite, occurring in rats, pigs, and man, and is responsibl...

tree frog

(Encyclopedia)tree frog, name for any of the small tree- or shrub-inhabiting frogs of the family Hylidae, characterized by an adhesive disk on the tip of each of the clawlike toes. This family has about 300 species...

air mass

(Encyclopedia)air mass, large body of air within the earth's atmosphere in which temperature and humidity, although varying at different heights, remain similar throughout the body at any one height. Air masses for...

Sheffield plate

(Encyclopedia)Sheffield plate, metalware of copper, silver-plated by fusion, originated at Sheffield, England. This process of plating was discovered c.1742 by a Sheffield cutler, Thomas Boulsover, who found while ...

nationalization

(Encyclopedia)nationalization, acquisition and operation by a country of business enterprises formerly owned and operated by private individuals or corporations. State or local authorities have traditionally taken ...
 

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