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Watertown

(Encyclopedia)Watertown. 1 Town (1990 pop. 20,456), Litchfield co., W Conn.; set off from Waterbury and inc. 1780. Textiles, plastics, chemicals, mattresses, and brass goods are among its manufactures. A method for...

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...

steam engine

(Encyclopedia)CE5 Steam engine steam engine, machine for converting heat energy into mechanical energy using steam as a medium, or working fluid. When water is converted into steam it expands, its volume increa...

silicon

(Encyclopedia)silicon, nonmetallic chemical element; symbol Si; at. no. 14; interval in which at. wt. ranges 28.084–28.086; m.p. 1,410℃; b.p. 2,355℃; sp. gr. 2.33 at 25℃; valence usually +4. Silicon is the ...

child abuse

(Encyclopedia)child abuse, physical, sexual, or emotional maltreatment or neglect of children by parents, guardians, or others responsible for a child's welfare. Physical abuse is characterized by physical injury, ...

electron tube

(Encyclopedia)CE5 Triode electron tube electron tube, device consisting of a sealed enclosure in which electrons flow between electrodes separated either by a vacuum (in a vacuum tube) or by an ionized gas at l...

diode

(Encyclopedia)diode dīˈōd [key], two-terminal electronic device that permits current flow predominantly in only one direction. Most diodes are semiconductor devices; diode electron tubes are now used only for a ...

Heaney, Seamus

(Encyclopedia)Heaney, Seamus (Seamus Justin Heaney) shāˈməs, hēˈnē [key], 1939–2013, Irish poet, one of the finest contemporary English poets, b. Londonderry (now Derry), Northern Ireland, grad. Queen's Uni...

atomic clock

(Encyclopedia)atomic clock, electric or electronic timekeeping device that is controlled by atomic or molecular oscillations. A timekeeping device must contain or be connected to some apparatus that oscillates at a...

molybdenum

(Encyclopedia)molybdenum məlĭbˈdənəm [key] [Gr.,=leadlike], metallic chemical element; symbol Mo; at. no. 42; at. wt. 95.96; m.p. about 2,617℃; b.p. about 4,612℃; sp. gr. 10.22 at 20℃; valence +2, +3, +4...