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Kastler, Alfred

(Encyclopedia)Kastler, Alfred, 1902–84, German-born French physicist, Ph.D. Univ. of Bordeaux, 1936. Kastler was a lecturer at Clermont-Ferrand Univ. (1936–38), professor at the Univ. of Bordeaux (1938–41), p...

Boltwood, Bertram Borden

(Encyclopedia)Boltwood, Bertram Borden, 1870–1927, American chemist and physicist, b. Amherst, Mass., grad. Sheffield Scientific School, Yale, 1892. After graduate study at Leipzig and Yale (Ph.D., 1897), he taug...

Bridges, Simon Joseph

(Encyclopedia)Bridges, Simon Joseph, 1976–, New Zealand lawyer and politician, b. Auckland. A Maori and a member of the conservative National party, Bridges was a lawyer and prosecutor before he was first elected...

degree-day

(Encyclopedia)degree-day, a unit of measure used to estimate the fuel and power requirements in heating and cooling a building; it is equal to a difference of 1 degree between the outdoor daily average temperature ...

fatigue, in physiology

(Encyclopedia)fatigue, in physiology, inability to perform reasonable and necessary physical or mental activity. Muscle fatigue, for example, results when the contractile properties of muscle are reduced, and conti...

gamma radiation

(Encyclopedia)gamma radiation, high-energy photons emitted as one of the three types of radiation resulting from natural radioactivity. It is the most energetic form of electromagnetic radiation, with a very short ...

metabolism

(Encyclopedia)metabolism, sum of all biochemical processes involved in life. Two subcategories of metabolism are anabolism, the building up of complex organic molecules from simpler precursors, and catabolism, the ...

nitric oxide

(Encyclopedia)nitric oxide or nitrogen monoxide, a colorless gas formed by the combustion of nitrogen and oxygen as given by the reaction: energy + N2 + O2 → 2NO; m.p. −163.6℃; b.p. −151.8℃. Nitric oxide ...

hydrogen

(Encyclopedia)hydrogen hīˈdrəjən [key] [Gr.,=water forming], gaseous chemical element; symbol H; at. no. 1; interval in which at. wt. ranges 1.00784–1.00811; m.p. −259.14℃; b.p. −252.87℃; density 0.08...

Economic Community of West African States

(Encyclopedia)Economic Community of West African States (ECOWAS), organization established in 1975 to increase economic cooperation and development in West Africa. Members include Benin, Burkina Faso, Cape Verde, C...