单词	furan
释义	furan /ˈfjʊəran / noun [mass noun] Chemistry 1A colourless volatile liquid with a planar unsaturated five-membered ring in its molecule. Chemical formula: C4H4O. Furfural reacts with phenols, ketones, and esters as an aldehyde; removal of the aldehyde group yields furan, which is converted to tetrahydrofuran, used in the manufacture of nylon.... Cycloadditon of one of the double bonds on either the furan or the pyrone ring of a psoralen molecule forms a monoadduct. Several studies have demonstrated that only the 5-nitrofurans are mutagenic and that derivatives with the nitro group outside the furan ring do not show mutagenic activity. 1.1 [count noun] Any substituted derivative of furan.According to Marcocchio, and the World Health Organization, dioxins are linked to cancer, birth defects and auto-immune problems, while furans are chemically similar but slightly less toxic.... Dioxins, and furans, are chemical compounds generated as by-products of most forms of combustion, particularly of plastics and rubber. This argument was presented in a modified form to the effect that the system of monitoring for dioxins and furans (other objectionable organic pollutants) was unreasonable and contrary to Articles 2 and 8 of the Convention. Origin Late 19th century: from synonymous furfuran.
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