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solar energy

(Encyclopedia)solar energy, any form of energy radiated by the sun, including light, radio waves, and X rays, although the term usually refers to the visible light of the sun. Solar energy is needed by green plants...

insulation

(Encyclopedia)insulation ĭnˌsəlāˈshən, ĭnˌsyo͝o– [key], use of materials or devices to inhibit or prevent the conduction of heat or of electricity. Common heat insulators are, fur, feathers, fiberglass, ...

Clausius, Rudolf Julius Emanuel

(Encyclopedia)Clausius, Rudolf Julius Emanuel ro͞oˈdôlf yo͞oˈlyo͝os āmäˈno͞oĕl klouˈzēo͝os [key], 1822–88, German mathematical physicist. A pioneer in the science of thermodynamics, he introduced th...

Rumford, Benjamin Thompson, Count

(Encyclopedia)Rumford, Benjamin Thompson, Count, 1753–1814, American-British scientist and administrator, b. Woburn, Mass. In 1776 he went to England, where he served (1780–81) as undersecretary of the colonies...

duralumin

(Encyclopedia)duralumin do͝orălˈyəmĭn, dyo͝o– [key], alloy of aluminum (over 90%) with copper (about 4%), magnesium (0.5%–1%), and manganese (less than l%). Before a final heat treatment the alloy is duct...

perpetual-motion machine

(Encyclopedia)perpetual-motion machine, device that would be able to operate continuously and supply useful work, in violation of the laws of thermodynamics. A machine that would produce more energy in the form of ...

vaporization

(Encyclopedia)vaporization, change of a liquid or solid substance to a gas or vapor. There is fundamentally no difference between the terms gas and vapor, but gas is used commonly to describe a substance that appea...

carboloy

(Encyclopedia)carboloy kärˈbəloi [key] [portmanteau word from carbon and alloy], an alloy containing cobalt, tungsten, and carbon. This alloy is extremely hard, harder than steel; it is used to cut steel, porcel...

boiler

(Encyclopedia)boiler, device for generating steam. It consists of two principal parts: the furnace, which provides heat, usually by burning a fuel, and the boiler proper, a device in which the heat changes water in...

hysteresis

(Encyclopedia)hysteresis hĭsˌtərēˈsĭs [key], phenomenon in which the response of a physical system to an external influence depends not only on the present magnitude of that influence but also on the previous...