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ammonia

(Encyclopedia)ammonia, chemical compound, NH3, colorless gas that is about one half as dense as air at ordinary temperatures and pressures. It has a characteristic pungent, penetrating odor. Ammonia forms a minute ...

aniline

(Encyclopedia)aniline ănˈəlĭn [key], C6H5NH2, colorless, oily, basic liquid organic compound; chemically, a primary aromatic amine whose molecule is formed by replacing one hydrogen atom of a benzene molecule w...

amortization

(Encyclopedia)amortization ămˌərtəzāˈshən, əmôrˈ– [key], reduction, liquidation, or satisfaction of a debt. The term amortization may also refer to the sum used for that purpose. The term is commonly us...

depreciation

(Encyclopedia)depreciation, in accounting, reduction in the value of fixed or capital assets, as by use, damage, weathering, or obsolescence. It can be estimated according to a number of methods. In the straight-li...

ferret

(Encyclopedia)ferret, name for a domesticated polecat, Mustela putorius, common in the Old World. It has been used for centuries to hunt rats, mice, and rabbits. Domestic ferrets are found in many color types inclu...

Rayonnant style

(Encyclopedia)Rayonnant style rāˈənănt [key], the middle period (c.1240–1350) of French Gothic architecture, so termed from the characteristic radiating tracery of the rose window. In this period many of the ...

Ripon, Frederick John Robinson, 1st earl of

(Encyclopedia)Ripon, Frederick John Robinson, 1st earl of rĭpˈən [key], 1782–1859, British statesman, better known as Viscount Goderich. Entering Parliament as a Tory in 1806, he sponsored the unpopular corn l...

sleep apnea

(Encyclopedia)sleep apnea, episodes of interrupted breathing during sleep. Obstructive sleep apnea is a common disorder in which relaxation of muscles in the throat repeatedly close off the airway during sleep; the...

Yudhoyono, Susilo Bambang

(Encyclopedia)Yudhoyono, Susilo Bambang so͞osēˈlō bämbäng yo͞oˈdōyōˌnō [key], 1949–, Indonesian army officer and political leader, popularly known as SBY, president of Indonesia (2004–), b. Pacitan,...

airfoil

(Encyclopedia)airfoil, surface designed to develop a desired force by reaction with a fluid, especially air, that is flowing across the surface. For example, the fixed wing surfaces of an airplane produce lift, whi...