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Fleming, Sir Sandford

(Encyclopedia)Fleming, Sir Sandford: see standard time. ...

caisson

(Encyclopedia)caisson kāˈsən, –sŏn [key] [Fr.,=big box], in engineering, a chamber, usually of steel but sometimes of wood or reinforced concrete, used in the construction of foundations or piers in or near a...

refrigeration

(Encyclopedia)CE5 Compression system of refrigeration refrigeration, process for drawing heat from substances to lower their temperature, often for purposes of preservation. Refrigeration in its modern, portabl...

sleep

(Encyclopedia)sleep, resting state in which an individual becomes relatively quiescent and relatively unaware of the environment. During sleep, which is in part a period of rest and relaxation, most physiological f...

Bunsen burner

(Encyclopedia)Bunsen burner, gas burner, commonly used in scientific laboratories, consisting essentially of a hollow tube which is fitted vertically around the flame and which has an opening at the base to admit a...

Osheroff, Douglas Dean

(Encyclopedia)Osheroff, Douglas Dean, 1945–, American physicist, b. Aberdeen, Wash., Ph.D. Cornell, 1973. He was a professor at Cornell from 1973 to 1987, when he joined the faculty at Stanford. Osheroff was also...

Carnot, Nicolas Léonard Sadi

(Encyclopedia)Carnot, Nicolas Léonard Sadi kärnōˈ [key], 1796–1832, French physicist, a founder of modern thermodynamics; son of Lazare N. M. Carnot. His famous work on the motive power of heat (Réflexions ...

corns and calluses

(Encyclopedia)corns and calluses, thickenings of the outer layer of skin where there is irritation or constant pressure. Corns are cone-shaped with their points protruding into the dermis, or inner layer of skin. T...

Haber process

(Encyclopedia)Haber process häˈbər [key], commercial process for the synthesis of ammonia, NH3. Pure hydrogen and nitrogen gases are mixed in the appropriate proportion, heated to between 450℃ and 600℃, comp...

Dionysius Thrax

(Encyclopedia)Dionysius Thrax [Lat.,=the Thracian], c.170–c.90 b.c., Greek grammarian of Alexandria. His Art of Grammar remained a standard work for centuries and was a model for subsequent grammars. ...