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catalyst
(Encyclopedia)catalyst, substance that can cause a change in the rate of a chemical reaction without itself being consumed in the reaction; the changing of the reaction rate by use of a catalyst is called catalysis...Chauvin, Yves
(Encyclopedia)Chauvin, Yves, 1930–2015, French chemist, b. Menen, Belgium, grad. Lyon School of Chemistry, Physics, and Electronics (CPE), 1954. Chauvin was a research engineer (1960–91) and then research direc...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...Ertl, Gerhard
(Encyclopedia)Ertl, Gerhard gĕrˈhärt ârˈtəl [key], 1936– German chemist, b. Stuttgart, grad. Univ. of Stuttgart (1961), Technical Univ., Munich (Ph.D 1965). After holding a number of lecturer and research p...platinum
(Encyclopedia)platinum plătˈənəm [key], metallic chemical element; symbol Pt; at. no. 78; at. wt. 195.084; m.p. 1,772℃; b.p. 3,827±100℃; sp. gr. 21.45 at 20℃; valence +2 or +4. Pure platinum is a malleab...aniline
(Encyclopedia)aniline ănˈəlĭn [key], C6H5NH2, colorless, oily, basic liquid organic compound; chemically, a primary aromatic amine whose molecule is formed by replacing one hydrogen atom of a benzene molecule w...surface chemistry
(Encyclopedia)surface chemistry, study of chemical reactions in which the reactants are first adsorbed onto a surface medium (see adsorption) that then acts as a catalyst for the reaction; after the reaction the pr...barbed wire
(Encyclopedia)barbed wire, wire composed of two zinc-coated steel strands twisted together and having barbs spaced regularly along them. The need for barbed wire arose in the 19th cent. as the American frontier mov...silica gel
(Encyclopedia)silica gel, chemical compound. It is a colloidal form of silica, and usually resembles coarse white sand. It may be prepared by partial dehydration of metasilicic acid, H2SiO3. Because it has many tin...aerogel
(Encyclopedia)aerogel, any of a group of extremely light and porous solid materials; the lightest is less than four times as dense as dry air. Aerogels are produced from certain gels (see colloid) by heating the ge...Browse by Subject
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