Events Calendar

Seminar: Fate and Transport of nano-TiO2 in Aquatic Environments

Speaker: Sharon L. Walker Associate Professor and the John Babbage Chair in Environmental Engineering University of California Riverside,

Abstract: Fate and transport of nanoparticles in aquatic environments have been investigated utilizing nano-TiO2, as it is one of the most widely used nanomaterials in industry. The project was developed to identify the fundamental mechanisms involved in the transport of nano-TiO2 and the contribution of various environmental parameters including solution chemistry (pH, ionic strength, and ion valence), hydrodynamic effects, and the presence of natural organic matter(NOM). Complementary transport studies have been conducted in both macroscopic (packedbed column) and microscopic (parallel plate flow cell) systems. Additionally, extensive
physical-chemical characterization of the nanoparticles was conducted under these various solution conditions. The combination of these transport and characterization tools has
demonstrated the critical role that pH, ionic strength and valence, NOM, and aggregation state play in the transport. Results from both transport systems and particle characterization will be presented, as well as the proposed transport and retention mechanisms observed. Additionally, a
brief overview of Walker’s research in bacterial pathogen fate and transport will be discussed as well.

Biography: Sharon Walker received her Ph.D. in Environmental Engineering, from the Department of Chemical Engineering at Yale University in 2004. She earned her M.S. in Chemical and Environmental Engineering from Yale in 2000 and two Bachelor of Science degrees from the University of Southern California in Environmental Engineering and Environmental Studies in 1998. She is a member of the American Chemical Society (ACS), American Institute of Chemical Engineers (AIChE), American Society of Microbiology (ASM), Association for Environmental Engineering and Science Professors (AEESP), Air and Waste Management
Association (AWMA), Association of Women in Science (AWIS), and Society of Women Engineers (SWE). She is also a member of Chi Epsilon and Tau Beta Pi. She is currently a faculty advisor to the UC Riverside Alpha Beta chapter of Tau Beta Pi and campus chapter of SWE. She was awarded the 2010 NSF Career Award and she was a Fulbright Scholar at Ben Gurion University of the Negev in Israel during the 2009-2010 school year.

Audiences: Everyone Is Invited

Contact: Evangeline Reyes