1. Institute of Bioproducts and Paper Technology, Graz University of Technology, Inffeldgasse 23, Graz 8010, Austria
2. Christian Doppler Laboratory for Fiber Swelling and Paper Performance, Boltzmanngasse 20/1/3, Vienna 1090, Austria
3. Institute of Analytical Chemistry and Food Chemistry, Graz University of Technology, Stremayrgasse 9/II, Graz 8010, Austria