cyclic efficiency of mechanism
51Combustion — This article is about the process of burning. For combustion without external ignition, see spontaneous combustion. For the engine used in mobile propulsion, see internal combustion engine. For the visible part of a fire, see flame. Burning… …
52river — river1 riverless, adj. riverlike, adj. /riv euhr/, n. 1. a natural stream of water of fairly large size flowing in a definite course or channel or series of diverging and converging channels. 2. a similar stream of something other than water: a… …
53coal utilization — Introduction combustion of coal or its conversion into useful solid, gaseous, and liquid products. By far the most important use of coal is in combustion, mainly to provide heat to the boilers of electric power plants. Metallurgical coke… …
54RAID — This article is about the data storage technology. For other uses, see Raid (disambiguation). RAID, an acronym for Redundant Array of Independent Disks (originally Redundant Array of Inexpensive Disks),[1] is a storage… …
55United States — a republic in the N Western Hemisphere comprising 48 conterminous states, the District of Columbia, and Alaska in North America, and Hawaii in the N Pacific. 267,954,767; conterminous United States, 3,022,387 sq. mi. (7,827,982 sq. km); with… …
56Список награждённых Национальной медалью науки США — Джошуа Ледерберг (справа) получает Национальную медаль науки из рук Президента США Джорджа Буша старшего Список …
57biosphere — biospheric /buy euh sfer ik/, adj. /buy euh sfear /, n. 1. the part of the earth s crust, waters, and atmosphere that supports life. 2. the ecosystem comprising the entire earth and the living organisms that inhabit it. [1895 1900; < G Biosphäre; …
58Attribution of recent climate change — Further information: Global warming, Climate change, and Climate change denial Attribution of recent climate change is the effort to scientifically ascertain mechanisms responsible for recent changes observed in the Earth s climate …
59aging — ag·ing (āʹjĭng) n. 1. The process of growing old or maturing. 2. An artificial process for imparting the characteristics and properties of age. * * * Gradual change in an organism that leads to increased risk of weakness, disease, and death. It… …
60photography, technology of — Introduction equipment, techniques, and processes used in the production of photographs. The most widely used photographic process is the black and white negative–positive system (Figure 1 >). In the camera the lens projects an image of… …
