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ecology

(Encyclopedia)ecology, study of the relationships of organisms to their physical environment and to one another. The study of an individual organism or a single species is termed autecology; the study of groups of ...

aviation

(Encyclopedia)aviation, operation of heavier-than-air aircraft and related activities. Aviation can be conveniently divided into military aviation, air transport, and general aviation. Military aviation includes al...

energy, sources of

(Encyclopedia)energy, sources of, origins of the power used for transportation, for heat and light in dwelling and working areas, and for the manufacture of goods of all kinds, among other applications. The develop...

art conservation and restoration

(Encyclopedia)art conservation and restoration, the preservation of structurally sound works of art, the halting of processes that lead to the damage of works of art, and the repair of already damaged works of art....

forest

(Encyclopedia)forest, a dense growth of trees, together with other plants, covering a large area of land. The science concerned with the study, preservation, and management of forests is forestry. A forest is an ec...

Shanghai

(Encyclopedia)Shanghai shăngˈhīˈ, shängˈhīˈ [key], city and municipality (2010 pop. 23,019,148), in, but independent of, Jiangsu prov., E China, on the Huangpu (Whangpoo) River where it flows into the Chang...

petroleum

(Encyclopedia)petroleum, oily, flammable liquid that occurs naturally in deposits, usually beneath the surface of the earth; it is also called crude oil. It consists principally of a mixture of hydrocarbons, with t...

turtle

(Encyclopedia)turtle, a reptile of the order Chelonia, with strong, beaked, toothless jaws and, usually, an armorlike shell. The shell normally consists of bony plates overlaid with horny shields. The upper portion...

observatory

(Encyclopedia)observatory, scientific facility especially equipped to detect and record naturally occurring scientific phenomena. Although geological and meteorological observatories exist, the term is generally ap...

deafness

(Encyclopedia)deafness, partial or total lack of hearing. It may be present at birth (congenital) or may be acquired at any age thereafter. A person who cannot detect sound at an amplitude of 20 decibels in a frequ...