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econometrics

(Encyclopedia)econometrics, technique of economic analysis that expresses economic theory in terms of mathematical relationships and then tests it empirically through statistical research. Econometrics attempts to ...

allergy

(Encyclopedia)allergy, hypersensitive reaction of the body tissues of certain individuals to certain substances that, in similar amounts and circumstances, are innocuous to other persons. Allergens, or allergy-caus...

hassium

(Encyclopedia)hassium hăsˈēəm, häsˈ– [key], artificially produced radioactive chemical element; symbol Hs; at. no. 108; mass number of most stable isotope 277; m.p., b.p., sp. gr., and valence unknown. Situ...

Herat

(Encyclopedia)Herat hĕrätˈ [key], city (1984 est. pop. 161,000), capital of Herat prov., NW Afghanistan, on the Hari Rud. The fertile river valley is renowned for its fruits, especially grapes. Herat has textile...

cerium

(Encyclopedia)cerium sērˈēəm [key] [from the asteroid Ceres], metallic chemical element; symbol Ce; at. no. 58; at. wt. 140.116; m.p. 799℃; b.p. 3,426℃; sp. gr. 6.77 at 25℃; valence +3 or +4. Cerium is a ...

urea

(Encyclopedia) CE5 urea yo͝oēˈə [key], organic compound that is the principal end product of nitrogen metabolism in most mammals. Urea was the first animal metabolite to be isolated in crystalline form; its c...

tracer

(Encyclopedia)tracer, an identifiable substance used to follow the course of a physical, chemical, or biological process. In chemistry the ideal tracer has the same chemical properties as the molecule it replaces a...

dating

(Encyclopedia)dating, the determination of the age of an object, of a natural phenomenon, or of a series of events. There are two basic types of dating methods, relative and absolute. In relative dating, the tempor...

stoneware

(Encyclopedia)stoneware, hard pottery made from siliceous paste, fired at high temperature to vitrify (make glassy) the body. Stoneware is heavier and more opaque than porcelain and differs from terra-cotta in bein...

Barth, Karl

(Encyclopedia)Barth, Karl bärt [key], 1886–1968, Swiss Protestant theologian, one of the leading thinkers of 20th-century Protestantism. He helped to found the Confessing Church and his thinking formed the theol...
 

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