1. Department of Chemistry; Memorial University of Newfoundland; St. John's Newfoundland A1B 3V6 Canada
2. Department of Chemistry, Faculty of Science; Damanhour University; Damanhour Egypt
3. Department of Chemistry, Faculty of Science; Alexandria University; Ibrahimia, PO Box 426 Alexandria 21321 Egypt
4. NIDDK, LBC, National Institutes of Health; Bethesda MD 20892-0815 USA
5. Fisheries and Oceans Canada, Science Branch, Environmental Sciences Division; Special Projects, P.O. Box 5667 St John's Newfoundland A1C 5X1 Canada