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naphtha

(Encyclopedia)naphtha năpˈthə, năfˈ– [key], term usually restricted to a class of colorless, volatile, flammable liquid hydrocarbon mixtures. Obtained as one of the more volatile fractions in the fractional ...

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 ...

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...

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...

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 ...

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...

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...

Warm Springs

(Encyclopedia)Warm Springs, resort, Meriwether co., W Ga. The salutary properties of the water springing from Pine Mt. were known to Native Americans, and white settlers learned of them in the late 18th cent. By th...