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sweetener, artificial

(Encyclopedia)sweetener, artificial, substance used as a low-calorie sugar substitute. Saccharin, cyclamates, and aspartame have been the most commonly used artificial sweeteners. Saccharin, a coal-tar derivative t...

bee fly

(Encyclopedia)bee fly, name for the small- to medium-sized flies of the family Bombyliidae, many of which resemble bees in appearance and behavior. This mimicry provides bee flies with some measure of protection ag...

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...

San Salvador, city, El Salvador

(Encyclopedia)San Salvador sän sälväᵺōrˈ [key], city (1993 pop. 402,448), central El Salvador, capital and largest city of the country. It is the center of El Salvador's trade and communications. Beer, tobac...

resistance, in electricity

(Encyclopedia)resistance, property of an electric conductor by which it opposes a flow of electricity and dissipates electrical energy away from the circuit, usually as heat. Optimum resistance is provided by a con...

permafrost

(Encyclopedia)permafrost, permanently frozen soil, subsoil, or other deposit, characteristic of arctic and some subarctic regions; similar conditions are also found at very high altitudes in mountain ranges. In 196...

energy

(Encyclopedia)CE5 Relations between potential energy (PE) and kinetic energy (KE) for a swinging pendulum energy, in physics, the ability or capacity to do work or to produce change. Forms of energy include hea...

diffusion

(Encyclopedia)diffusion, in chemistry, the spontaneous migration of substances from regions where their concentration is high to regions where their concentration is low. Diffusion is important in many life process...

stove

(Encyclopedia)stove, device used for heating or for cooking food. The stove was long regarded as a cooking device supplementary to the fireplace, near which it stood; its stovepipe led into the fireplace chimney. I...

sulfuric acid

(Encyclopedia)sulfuric acid, chemical compound, H2SO4, colorless, odorless, extremely corrosive, oily liquid. It is sometimes called oil of vitriol. Although sulfuric acid is now one of the most widely used c...