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smoke

(Encyclopedia)smoke, visible gaseous product of incomplete combustion. Smoke varies with its source, but it usually comprises hot gas and suspended particles of carbon and tarry substances, or soot. To reduce the a...

oyster

(Encyclopedia)oyster, bivalve mollusk found in beds in shallow, warm waters of all oceans. The shell is made up of two valves, the upper one flat and the lower convex, with variable outlines and a rough outer surfa...

naturalism, in literature

(Encyclopedia)naturalism, in literature, an approach that proceeds from an analysis of reality in terms of natural forces, e.g., heredity, environment, physical drives. The chief literary theorist on naturalism was...

neural network

(Encyclopedia)neural network or neural computing, computer architecture modeled upon the human brain's interconnected system of neurons. Neural networks imitate the brain's ability to sort out patterns and learn fr...

poison

(Encyclopedia)poison, any agent that may produce chemically an injurious or deadly effect when introduced into the body in sufficient quantity. Some poisons can be deadly in minute quantities, others only if relati...

Pre-Raphaelites

(Encyclopedia)Pre-Raphaelites prēˌ-răfˈēəlītsˌ [key], brotherhood of English painters and poets formed in 1848 in protest against what they saw as the low standards and decadence of British art. The princip...

Bangkok

(Encyclopedia)Bangkok băngˈkŏkˌ [key], Thai Krung Thep, city (2021 est. pop. 10,539,000), capital of Th...

irrigation

(Encyclopedia)irrigation, in agriculture, artificial watering of the land. Although used chiefly in regions with annual rainfall of less than 20 in. (51 cm), it is also used in wetter areas to grow certain crops, e...

arrhythmia

(Encyclopedia)arrhythmia ārĭᵺˈmēə [key], disturbance in the rate or rhythm of the heartbeat. Various arrhythmias can be symptoms of serious heart disorders; however, they are usually of no medical significan...

ultraviolet radiation

(Encyclopedia)ultraviolet radiation, invisible electromagnetic radiation between visible violet light and X rays; it ranges in wavelength from about 400 to 4 nanometers and in frequency from about 1015 to 1017 hert...