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Kroto, Harry

(Encyclopedia)Kroto, Harry (Sir Harold Walter Kroto), 1939–2016, British chemist, b. Harold Walter Krotoschiner, Ph.D. Univ. of Sheffield, 1964. Kroto was the son of German parents who fled Nazi rule to England. ...

Cornell, Eric Allin

(Encyclopedia)Cornell, Eric Allin, 1961–, American physicist, b. Palo Alto, Calif., Ph.D. Massachusetts Institute of Technology, 1990. Since 1990, he has been a researcher at the Joint Institute for Laboratory As...

coherence

(Encyclopedia)coherence, constant phase difference in two or more Waves over time. Two waves are said to be in phase if their crests and troughs meet at the same place at the same time, and the waves are out of pha...

turpentine

(Encyclopedia)turpentine, yellow to brown semifluid oleoresin exuded from the sapwood of pines, firs, and other conifers. It is made up of two principal components, an essential oil and a type of resin that is call...

polyethylene

(Encyclopedia)polyethylene pŏlˌēĕthˈəlēn [key], widely used plastic. It is a polymer of ethylene, CH2=CH2, having the formula (–CH2–CH2–)n, and is produced at high pressures and temperatures in the pre...

Olah, George Andrew

(Encyclopedia)Olah, George Andrew, 1927–2017, American chemist, b. Budapest, Ph.D. Budapest Univ. of Technology and Economics, 1949. Olah was a researcher at Dow Chemical from 1957 to 1965 and a professor at West...

humus

(Encyclopedia)humus hyo͞oˈməs [key], organic matter that has decayed to a relatively stable, amorphous state. It is an important biological constituent of fertile soil. Humus is formed by the decomposing action ...

bronze, in metallurgy

(Encyclopedia)bronze, in metallurgy, alloy of copper, tin, zinc, phosphorus, and sometimes small amounts of other elements. Bronzes are harder than brasses. Most are produced by melting the copper and adding the de...

petrology

(Encyclopedia)petrology, branch of geology specifically concerned with the origin, composition, structure, and properties of rocks, primarily igneous and metamorphic, and secondarily sedimentary. It includes petrog...

pharmacopoeia

(Encyclopedia)pharmacopoeia or pharmocopeia färˌməkəpēˈə [key], authoritative publication designating the properties, action, use, dosage, and standards of strength and purity of drugs. It is compiled under ...