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forgery, in art

(Encyclopedia)forgery, in art, the false claim to authenticity for a work of art. A forger often unconsciously produces a confusion of styles or subtly accents elements reflecting contemporary bias. A major examp...

periodic table

(Encyclopedia)CE5 periodic table, chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arrange...

smoking

(Encyclopedia)smoking, inhalation and exhalation of the fumes of burning tobacco in cigars and cigarettes and pipes; in the 21st cent., vaping, the similar use of e-cigarettes, also has become common. Some persons ...

radio astronomy

(Encyclopedia)radio astronomy, study of celestial bodies by means of the electromagnetic radio frequency waves they emit and absorb naturally. Radio waves also come from outside the Milky Way. These extragalact...

protein

(Encyclopedia)protein, any of the group of highly complex organic compounds found in all living cells and comprising the most abundant class of all biological molecules. Protein comprises approximately 50% of cellu...

pollution

(Encyclopedia)pollution, contamination of the environment as a result of human activities. The term pollution refers primarily to the fouling of air, water, and land by wastes (see air pollution; water pollution; s...

Chordata

(Encyclopedia)CE5 Common features in representative groups of the phylum Chordata Chordata kôrdāˈtə, –däˈ– [key], phylum of animals having a notochord, or dorsal stiffening rod, as the chief internal ...

magnetism

(Encyclopedia)CE5 Lines of induction around a single bar magnet and between opposite poles of different magnets magnetism, force of attraction or repulsion between various substances, especially those made of i...

radioactivity

(Encyclopedia)CE5 Effects of a magnetic field on the products of radioactivity CE5 Disintegration series: Radioactive decay of radium-226 into lead-206 radioactivity, spontaneous disintegration or decay of t...

volcano

(Encyclopedia)volcano, vents or fissures in the earth's crust through which gases, molten rock, or lava, and solid fragments are discharged. Their study is called volcanology. The term volcano is commonly applied b...