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pressure-treated wood

(Encyclopedia)pressure-treated wood, wood that has had a liquid preservative forced into it in order to protect against deterioration due to rot or insect attack. The most commonly used preservatives are chromated ...

Ostwald, Wilhelm

(Encyclopedia)Ostwald, Wilhelm vĭlˈhĕlm ôstˈvält [key], 1853–1932, German physical chemist and natural philosopher, b. Riga, Latvia. He was professor of chemistry and director of the chemical laboratory (18...

barium

(Encyclopedia)barium bârˈēəm [key] [Gr.,=heavy], metallic chemical element; symbol Ba; at. no. 56; at. wt. 137.327; m.p. 725℃; b.p. 1,640℃; sp. gr. 3.5 at 20℃; valence +2. Barium is a soft, silver-white, ...

hematite

(Encyclopedia)hematite hĕmˈətīt [key], mineral, an oxide of iron, Fe2O3, containing about 70% metal, occurring in nature in red to reddish-brown earthy masses and in steel-gray to black crystalline forms. Hemat...

anhydride

(Encyclopedia)anhydride ănhīˈdrīd, –drĭd [key] [Gr.,=without water], chemical compound formed by removing water, H2O, from another compound; the anhydride can also react with water to form the original compo...

Goodenough, John Bannister

(Encyclopedia)Goodenough, John Bannister, 1922–2023, American physicist, b. Jena, Germany, Ph.D. Univ. of Chicago, 1952. Goodenough was a researcher at the Massachu...

verdigris

(Encyclopedia)verdigris vûrˈdəgrēsˌ [key], one of three copper acetates: blue verdigris, Cu(CH3COO)2·CuO·6H2O; green verdigris, 2Cu(CH3COO)2·CuO·6H2O; or neutral verdigris, Cu(CH3COO)2·H2O; or a mixture o...

corrosion

(Encyclopedia)corrosion, atmospheric oxidation of metals (see oxidation and reduction). By far the most important form of corrosion is the rusting of iron. Rusting is essentially a process of oxidation in which iro...

earth, in chemistry

(Encyclopedia)earth, in chemistry, metallic oxide not readily reducible by chemical means, e.g., alkaline earths, rare earths, and alumina. The name is also applied to certain absorbent clays, e.g., fuller's earth,...

abrasive

(Encyclopedia)abrasive, material used to grind, smooth, cut, or polish another substance. Natural abrasives include sand, pumice, corundum, and ground quartz. Carborundum (silicon carbide) and alumina (aluminum oxi...