1. Center for the Environmental
Implications of NanoTechnology (CEINT), Duke University, Durham, North Carolina 27708,
2. Department of Civil & Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213,
3. Department of Geological & Environmental Sciences, Stanford University, Stanford, California 94305, United States
4. Department of Chemistry, Duke University, Durham, NC27708,
5. Stanford Synchrotron Radiation
Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
6. Department of Photon Science, SLAC National Accelerator Laboratory, Menlo Park, California
94025, United States