May 31, 2023

Professor Sharpless Publishes Articles

Chemistry Professor Charles Sharpless is the co-author of two recently published articles. The first, entitled “Photooxidation-induced changes in optical, electrochemical, and photochemical properties of humic substances,” was co-authored with colleagues from U.C. Berkeley and the Swiss Federal Institute of Technology (ETH Zurich) and appears in the current issue of the American Chemical Society journal, Environmental Science & Technology. A research article, it focuses on how prolonged exposure to solar radiation alters the photochemical and electrochemical properties of natural dissolved organic matter, ubiquitous brown “stuff” in surface waters that participates in many aspects of environmental aquatic chemistry. The second article, entitled “The importance of charge-transfer interactions in determining chromophoric dissolved organic matter (CDOM) optical and photochemical properties,” was co-authored with Professor Neil Blough (Chemistry, U. MD College Park). This was an invited review for the Royal Society of Chemistry’s journal, Environmental Sciences: Processes and Impacts, formerly The Journal of Environmental Modeling. The review, containing 247 references, deals with the optical and photochemical properties of natural dissolved organic matter, how those properties are related, and the relevance of these relationships for current research in environmental photochemistry. The article is currently in advance electronic format and will be published later this year in a specially-themed journal issue devoted to aquatic photochemical processes.

Charlie Sharpless Receives NSF Grant to Study Fate of Marine Oil Spills

Recent research shows that oil in marine systems ages in ways inconsistent with current models.  Specifically, the hydrocarbon fraction has long been assumed to get oxidized, become more water soluble, and then biologically or abiotically degrade, eventually to CO2.  Researchers at the Woods Hole Oceanographic Institution have discovered that oxidized hydrocarbons actually constitute a sizable portion of the recalcitrant tar that remains at the late stages of a spill.   This process is presumably important in the weathering of natural oil seeps as well, which constitute the majority of oceanic oil.  Charlie and colleagues at Woods Hole and the University of California, Santa Barbara have received funding from the National Science Foundation, Division of Chemical Oceanography to study the extent to which photochemical and microbial processes drive this oxidation process.  The project, entitled “Oxygenation of Hydrocarbons in the Ocean” is a three-year study that will provide opportunities for UMW students to travel to and study at WHOI and UCSB as well as participate in a cruise in the Gulf  of Mexico to sample oil at various stages of weathering.