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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...

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...

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...

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...

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...

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 ...

seismology

(Encyclopedia)seismology sīzmŏlˈəjē, sīs– [key], scientific study of earthquakes and related phenomena, including the propagation of waves and shocks on or within the earth by natural or artificially genera...

map

(Encyclopedia)map, conventionalized representation of spatial phenomena on a plane surface. Unlike photographs, maps are selective and may be prepared to show various quantitative and qualitative facts, including b...

dark matter

(Encyclopedia)dark matter, material that is believed to make up nearly 27% of the mass of the universe but is not readily visible because it neither emits nor reflects electromagnetic radiation, such as light or ra...

adaptation

(Encyclopedia)adaptation, in biology, has several meanings. It can mean the adjustment of living matter to environmental conditions and to other living things either in an organism's lifetime (physiological adaptat...
 

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