Research

Current Research Projects (2018-Present)

Pet Food Project Logo“Refining and testing methods for identifying and quantifying gaseous oxidized mercury in air” (NSF)
Collaborators: Mae Gustin, Seth Lyman

“Algae from waste waters as a sustainable protein source: Fate of heavy metals” (USDA)
Collaborators: Sage Hiibel, Mae Gustin

“Study of the biochemical mechanisms by which mercury is sequestered in plants”
Collaborators: Won-Gyu Choi, Mae Gustin, Jeff Harper

“Pet Food Mercury & Genetics Experiment at University of Nevada, Reno: Determining percent methylmercury and identifying sources of protein contamination in companion animal foods and treats”
Collaborators: Mae Gustin, Mike Teglas, Mary Peacock, Kelly Klingler, Margarita Vargas Estrada

“Assessment of the variation in tree ring mercury concentrations between co-located tree species”
Collaborators: Ben Ingle, Mae Gustin

Past Research

2016-2018: Postdoctoral Scholar, University of Nevada, Reno
This research focused on identifying controlling factor(s) on organic carbon-mineral associations in soil environments and characterizing and quantifying plant-soil relationships in old fields in arid shrublands undergoing restoration.
Mentors: Ben Sullivan, Elizabeth Leger, Yu Yang
Affiliations: Global Water Center

Fall 2011: Research Assistant & Site Manager, Stanford Linear Accelerator Center
On this project, I coordinated and executed uranium aqueous chemistry field research at the Department of Energy Rifle, CO Integrated  Field  Research  Center. I managed  and assisted with various projects  and  collaborated  with  national  and international research teams to collect, process, compile and organize data for publication. I utilized analytical techniques (e.g. KPA, IC, UV-Vis, XAS, EM) to probe the behavior and fate of uranium, and other contaminants, as a function of redox potential in an in situ groundwater system experiencing several treatments.
Supervisor: John Bargar

2007-2012: Graduate Research Assistant, University of Notre Dame
My graduate research focused on biomineralization and biosorption involving bacteria. I investigated the effects of non-metabolizing bacteria on the precipitation of metal phosphates and proposed a novel mechanism of biomineralization in a uranium-phosphate system. I utilized many techniques (e.g. XRD, XAS, ICP-OES/MS, SEM, TEM, TOC) to gather geochemical and visual data. I also investigated the effects of various ligands (e.g. chloride, fulvic acid) on mercury behavior in the presence and absence of a variety of non-metabolizing bacteria (e.g. Gram+, Gram-, obligate anaerobes). Thermodynamic modeling of the batch adsorption data was conducted to generate stability constants and Kd values for the mercury-bacterium interactions.
Advisor: Jeremy Fein

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