1. Instrumental
Analytical Chemistry, University of Duisburg-Essen, Universitätsstrasse 5, 45141 Essen, Germany
2. Centre
for Water and Environmental Research (ZWU), University of Duisburg-Essen, Universitätsstrasse
2, 45141 Essen, Germany
3. IWW Water Centre, Moritzstraße
26, 45476 Mülheim
an der Ruhr, Germany