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stellar structure
(Encyclopedia)stellar structure, physical properties of a star and the processes taking place within it. Except for that of the sun, astronomers must draw their conclusions regarding stellar structure on the basis ...hypertension
(Encyclopedia)hypertension or high blood pressure, elevated blood pressure resulting from an increase in the amount of blood pumped by the heart or from increased resistance to the flow of blood through the small a...fuel injection
(Encyclopedia)fuel injection, system in an internal-combustion engine that delivers fuel or a fuel-air mixture to the cylinders by means of pressure from a pump. It was originally used in diesel engines because of ...Bergius, Friedrich Karl Rudolf
(Encyclopedia)Bergius, Friedrich Karl Rudolf, 1884–1949, German chemist, Ph.D. Univ. of Leipzig, 1907. In 1910, Bergius set up a laboratory to carry out his research and in 1914 transferred the operation to the E...nosebleed
(Encyclopedia)nosebleed, nasal hemorrhage occurring as the result of local injury or disturbance. Most nosebleeds are not serious and occur when one of the small veins of the septum (the partition between the nostr...kinetic-molecular theory of gases
(Encyclopedia)kinetic-molecular theory of gases, physical theory that explains the behavior of gases on the basis of the following assumptions: (1) Any gas is composed of a very large number of very tiny particles ...altitude
(Encyclopedia)altitude, vertical distance of an object above some datum plane, such as mean sea level or a reference point on the earth's surface. It is usually measured by the reduction in atmospheric pressure wit...caffeine
(Encyclopedia)caffeine kăfēnˈ [key], odorless, slightly bitter alkaloid found in coffee, tea, kola nuts (see cola), ilex plants (the source of the Latin American drink maté), and, in small amounts, in cocoa (se...placebo
(Encyclopedia)placebo pləsēˈbō [key], inert substance given instead of a potent drug. Placebo medications are sometimes prescribed when a drug is not really needed or when one would not be appropriate because t...drug poisoning
(Encyclopedia)drug poisoning, toxic effects caused by an administered drug. Worldwide more than 9 million natural and synthetic chemicals have been identified; fewer than 3000 cause more than 95% of acidental and d...Browse by Subject
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