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trypanosome

(Encyclopedia)trypanosome trĭpˈənəsōmˌ [key], microscopic, one-celled protozoan of the genus Trypanosoma, typically living as an active parasite in the bloodstream of a vertebrate; hundreds of species are kno...

acid rain

(Encyclopedia)acid rain or acid deposition, form of precipitation (rain, snow, sleet, or hail) containing high levels of sulfuric or nitric acids (pH below 5.5–5.6). Produced when sulfur dioxide and various nitro...

Bernoulli's principle

(Encyclopedia)CE5 Bernoulli's principle Bernoulli's principle, physical principle formulated by Daniel Bernoulli that states that as the speed of a moving fluid (liquid or gas) increases, the pressure within th...

tin

(Encyclopedia)tin, metallic chemical element; symbol Sn [Lat. stannum]; at. no. 50; at. wt. 118.710; m.p. 231.9681℃; b.p. 2,270℃; sp. gr. 5.75 (gray), 7.3 (white); valence +2 or +4. Tin exhibits allotropy; abov...

Petraeus, David Howell

(Encyclopedia)Petraeus, David Howell pĕtrāˈəs [key], 1952–, American military officer and government official, b. Cornwall, N.Y., studied West Point (B.S., 1974), U.S. Army Command and General Staff College (...

phenothiazine

(Encyclopedia)phenothiazine fēˌnəthīˈəzĭn [key], any one of a class of drugs used to control mental disorders. Phenothiazines, along with other antipsychotic, or neuroleptic, drugs are used for such disorder...

Raoult's law

(Encyclopedia)Raoult's law räo͞olzˈ [key] [for F. M. Raoult, a French physicist and chemist] states that the addition of solute to a liquid lessens the tendency for the liquid to become a solid or a gas, i.e., r...

rhenium

(Encyclopedia)rhenium rēˈnēəm [key], metallic chemical element; symbol Re; at. no. 75; at. wt. 186.207; m.p. about 3,180℃; b.p. about 5,625℃; sp. gr. 21.02 at 20℃; valence −1, +2, +3, +4, +5, +6, or +7....

stroke

(Encyclopedia)stroke, destruction of brain tissue as a result of intracerebral hemorrhage or infarction caused by thrombosis (clotting) or embolus (obstruction in a blood vessel caused by clotted blood or other for...

cerium

(Encyclopedia)cerium sērˈēəm [key] [from the asteroid Ceres], metallic chemical element; symbol Ce; at. no. 58; at. wt. 140.116; m.p. 799℃; b.p. 3,426℃; sp. gr. 6.77 at 25℃; valence +3 or +4. Cerium is a ...