Thomas Hermann has been announced the new president of the coatings and colorants business unit of Degussa AG as of July 1. The 38-year-old engineer replaced Dr. Klaus Burzin.      Degussa also announced that Walter Magee has been named marketing manager for the Aerosil fumed silica product line. He is responsible for marketing fumed silica to makers of silicone, glass precursors, ink jet media, optical fibers, defoamer chemicals and dispersions for the semi-conductor industry and other marke...