1. Nalco Energy Service, 7705 Highway 90-A, Sugar Land, Texas 77478, United States
2. Ion Cyclotron Resonance Program, National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, Florida 32310-4005, United States
3. Department of Chemistry and Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32306, United States
4. Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543-1543, United States
5. Schlumberger-Doll Research Center, 1 Hampshire Street, Cambridge, Massachusetts 02139-1578, United States