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Merkel, Angela

(Encyclopedia)Merkel, Angela änˈgĕlä märˈkəl [key], 1954–, German politician, b. Hamburg as Angela Dorothea Kasner. The daughter of a Lutheran pastor, she grew up in what was then East Germany. She trained...

amino group

(Encyclopedia)amino group, in chemistry, functional group that consists of a nitrogen atom attached by single bonds to hydrogen atoms, alkyl groups, aryl groups, or a combination of these three. An organic compound...

equation

(Encyclopedia)equation, in mathematics, a statement, usually written in symbols, that states the equality of two quantities or algebraic expressions, e.g., x+3=5. The quantity x+3, to the left of the equals sign (=...

Comte, Auguste

(Encyclopedia)Comte, Auguste ōgüstˈ kôNt [key], 1798–1857, French philosopher, founder of the school of philosophy known as positivism, educated in Paris. From 1818 to 1824 he contributed to the publications ...

promethium

(Encyclopedia)promethium prōmēˈthēəm [key], artificially produced radioactive chemical element; symbol Pm; at. no. 61; mass no. of most stable isotope 145; m.p. 1,042℃; b.p. 3,000℃ (estimated); sp. gr. unk...

oils

(Encyclopedia)oils, term commonly used to indicate a variety of greasy, fluid substances that are, in general, viscous liquids at ordinary temperatures, less dense than water, insoluble in water but soluble in alco...

berkelium

(Encyclopedia)berkelium bûrˈklēəm [key] [from Berkeley], artificially produced radioactive chemical element; symbol Bk; at. no. 97; mass no. of most stable isotope 247; m.p. about 1,050℃; b.p. about 2,590℃;...

lung cancer

(Encyclopedia)lung cancer, cancer that originates in the tissues of the lungs. Lung cancer is the leading cause of cancer death in the United States in both men and women. Like other cancers, lung cancer occurs aft...

violin

(Encyclopedia)CE5 Violins and viols violin, family of stringed musical instruments having wooden bodies whose backs and fronts are slightly convex, the fronts pierced by two ƒ-shaped resonance holes. The instr...

fermentation

(Encyclopedia)fermentation, process by which the living cell is able to obtain energy through the breakdown of glucose and other simple sugar molecules without requiring oxygen. Fermentation is achieved by somewhat...