%0 conference lecture %@ %A Ulbricht, M., Oechel, A., Schulze, H., Lehmann, C., Hicke, H.-G., Tomaschewski, G. %D 1993 %J ICOM '93: The 1993 International Congress on Membranes and Membrane Processes %T Chemical modification of polyacrylonitrile ultrafiltration membranes for enzyme immobilization %U %X