Porcine Reproductive and Respiratory Syndrome (PRRS) Authors: Jeff Zimmerman, Iowa State University; David Benfield, The Ohio State University; Jane Christopher-Hennings, South Dakota State University; Scott Dee, University of Minnesota; Greg Stevenson, Purdue University.
Therefore, the substance zirconia aluminosilicate refractory ceramic fibres (SiO 2, Al 2 O 3, ZrO 2) as described in this document are a subset of the group of substances which are defined by the refractory ceramic fibres in Annex VI of the Regulation (EC) No 1272/2008.
Silicon dioxide (SiO2), silicon's most common compound, is the most abundant compound in the earth's crust. It commonly takes the form of ordinary sand, but also exists as quartz, rock crystal, amethyst, agate, flint, jasper and opal. Silicon dioxide is extensively used in the manufacture of glass and bricks. Silica gel, a colloidal form of silicon dioxide, easily absorbs moisture and is used as a desiccant. Silicon forms other useful compounds. Silicon carbide (SiC) is nearly as hard as diamond and is used as an abrasive.