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barometer

(Encyclopedia)CE5 Aneroid barometer barometer bərŏmˈətər [key], instrument for measuring atmospheric pressure. It was invented in 1643 by the Italian scientist Evangelista Torricelli, who used a column...

metabolism

(Encyclopedia)metabolism, sum of all biochemical processes involved in life. Two subcategories of metabolism are anabolism, the building up of complex organic molecules from simpler precursors, and catabolism, the ...

evaporation

(Encyclopedia)evaporation, change of a liquid into vapor at any temperature below its boiling point. For example, water, when placed in a shallow open container exposed to air, gradually disappears, evaporating at ...

hydrogen chloride

(Encyclopedia)hydrogen chloride, chemical compound, HCl, a colorless, poisonous gas with an unpleasant, acrid odor. It is very soluble in water and readily soluble in alcohol and ether. It fumes in moist air. It is...

thermodynamics

(Encyclopedia)thermodynamics, branch of science concerned with the nature of heat and its conversion to mechanical, electric, and chemical energy. Historically, it grew out of efforts to construct more efficient he...

calorie

(Encyclopedia)calorie, abbr. cal, unit of heat energy in the metric system. The measurement of heat is called calorimetry. The calorie, or gram calorie, is the quantity of heat required to raise the temperature of ...

molar volume

(Encyclopedia)molar volume, the volume occupied by a mole of a substance at STP. According to Avogadro's law, at a given temperature and pressure a given volume of any gas contains the same number of molecules. At ...

starvation

(Encyclopedia)starvation, condition in which deprivation of food has forced the body to feed on itself. Causes are famine, fasting, malnutrition, or abnormalities of the mucosal lining of the digestive system. Fami...

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...

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...