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samadhi

(Encyclopedia)samadhi səmäˈdē [key], a state of deep absorption in the object of meditation, and the goal of many kinds of yoga. In Buddhism the term refers to any state of one-pointed concentration. In Hinduis...

oxygen tent

(Encyclopedia)oxygen tent, device used to maintain a patient in an oxygen-rich environment. The oxygen tent is composed of a clear plastic sheet suspended over the bed and tucked beneath the mattress to provide an ...

Oranienburg

(Encyclopedia)Oranienburg ōräˈnyənbo͝orkh [key], city (1994 pop. 28,320), Brandenburg, NE Germany, on the Havel River. It is a center of a fruit-growing region. Manufactures include chemicals and steel product...

ionosphere

(Encyclopedia)ionosphere īŏnˈəsfēr [key], series of concentric ionized layers forming part of the upper atmosphere of the earth from around 30 to 50 mi (50 to 80 km) to 250 to 370 mi (400 to 600 km) where it m...

parathyroid hormone

(Encyclopedia)parathyroid hormone or parathormone, a hormone secreted by the parathyroid glands that regulates the metabolism of calcium and phosphate in the body. It has been purified extensively and appears to be...

chlorofluorocarbons

(Encyclopedia)chlorofluorocarbons klōrˌəflo͝orˈəkärˌbənz, klôrˌ– [key] (CFCs), organic compounds that contain carbon, chlorine, and fluorine atoms. CFCs are highly effective refrigerants that were deve...

fluoride

(Encyclopedia)fluoride, a salt of hydrofluoric acid; see hydrogen fluoride. See also fluoridation; fluorine. ...

saturation, of an organic compound

(Encyclopedia)saturation, of an organic compound, condition occurring when its molecules contain no double or triple bonds and thus cannot undergo addition reactions. For example, ethane (H3C–CH3) is a saturated ...

cold fusion

(Encyclopedia)cold fusion or low-temperature fusion, nuclear fusion of deuterium, an isotope of hydrogen, at or relatively near room temperature. Fusion, the reaction involved in the release of the destructive ener...

flame

(Encyclopedia)flame, phenomenon associated with the chemical reaction of a gas that has been heated above its kindling temperature with some other gas, usually atmospheric oxygen (see combustion). The heat and ligh...