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The Office of Solid Waste of the US Environmental Protection Agency determines the hazards of wastes produced by the organic chemical manufacturing industry. Based on these determinations, regulations have been laid down for many wastes under the Resource Conservation and Recovery Act. Additional wastes from this industry will be considered for regulation(More)
Indium is a typical chalcophile element of the Earth's crust, with a very low average content that seldom forms specific minerals, occurring mainly as dispersed in polymetallic sulphides. Indium recovery is based primarily on zinc extraction from sphalerite, the prototype of so-called tetrahedral sulphides, wherein metal ions fill half of the available(More)
Abstract Brazil has one of the largest herds of cattle in the world, with more than 170 million heads. Over 400 farms have exported more than 2,875 ton (in 1997) of leather to Europe. The wet blue tanning process uses chemicals such as chromium compounds and produces liquid wastes that must be treated by physicochemical and biological systems. About 15,000(More)
Context. At the wavelength of 8 mm emissive features (high brightness temperatrue regions, HTRs) and absorptive features (low brightness temperature regions, LTRs) can be traced for the determination of the solar rotation. From earlier studies it is known that about two thirds of LTRs are associated with Hα filmaments. Thermal bremsstrahlung and(More)
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