GEOC 98 |
| Daniel W. O'Sullivan1, Christopher L. Osburn2, Richard B. Coffin2, and Thomas J. Boyd2. (1) Department of Chemistry, United States Naval Academy, 572 Holloway Road, Annapolis, MD 21402, (2) Marine Biogeochemistry, Naval Research Laboratory, Code 6114, 4555 Overlook Ave SW, Washington, DC 20375 |
| Hydrogen peroxide (H2O2) has been observed in significant concentrations in many natural waters. Since hydrogen peroxide can act as an oxidant and reductant, it participates in an extensive suite of reactions in surface waters. Hydrogen peroxide is produce as a secondary photochemical product of chromophoric dissolved organic matter (CDOM) photolysis. Quantum yields for the photochemical production of hydrogen peroxide and methylhydroperoxide (CH3O2H) were determined in filtered surface waters from several locations in the Chesapeake Bay and Arctic coastal waters with varying levels of CDOM. The relationship between the production of peroxides and measures of CDOM optical property changes, loss of absorbance and synchronous fluorescence, and CDOM chemical changes characterized by dissolved organic carbon production were examined. Peroxide production was greatest in waters containing significant amounts of terrigeneous C in the form of humic substances. Quantum yields for peroxide production and CDOM photobleaching were decoupled for the same water samples. |
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Poster Session
6:00 PM-9:00 PM, Tuesday, March 30, 2004 Anaheim Convention Center -- Hall A, Poster
Division of Geochemistry |