Microplastics (MPs) are plastic particles less than 5 mm in diameter. These contaminants are increasingly found in the environment due to increased plastic production, use, and improper disposal. Detecting and measuring these contaminants in the environment has proven difficult, requiring the use of fate and transport models to assess MP...
Per- and polyfluoroalkyl substances (PFAS) are a broad class of anthropogenic chemicals characterized by highly stable carbon-fluorine (C-F) bonds. PFAS are widely used in industrial and consumer products for their surface-active and stain-resistant properties and are ubiquitously detected in environmental media, biota, and human biomatrices. Although some PFAS are known...
Assessing the risk from exposure to a chemical mixture in the environment can seem prohibitively challenging. Most components of the mixture are not readily identifiable, chemicals may interact to cause other-than-additive toxicity, and the number of potential combinations of environmental contaminants is enormous. These challenges can make it seem impossible...
The finite element software framework, OpenSees, has been used by researchers
to simulate the response of structural and geotechnical systems to earthquake loading. Implementation of the Particle Finite Element Method (PFEM) has made it possible to simulate hydrodynamic forces through fluid-structure interaction (FSI) in OpenSees. To validate the FSI implementation...
Linkages between land use and its influence on the atmosphere have been a long-standing research area. For example, what is the impact of irrigated agriculture on downwind rainfall? Global-scale models show that moisture recycling is an important source of water for inland regions around the world, but they do not...
Low concentrations of dissolved copper have proven to be harmful to a number of aquatic organisms, with recent research highlighting detrimental effects to endangered salmonid species. Stormwater runoff can represent a significant source of copper to surface waters, necessitating cost-effective alternatives to current stormwater best management practices (BMPs). This study...
A new method is introduced for incorporating bathymetric uncertainty into predictions of nearshore and river flows (i.e., unstratified flows primarily forced by pressure and radiation stress gradients). The method involves the use of the ensemble Kalman filter (EnKF) as a parameter estimation scheme, where the parameter to be estimated is...
Understanding the transport of three fluid phases through porous media has important applications in subsurface contaminant remediation, oil and gas recovery, and geological CO₂ sequestration. Existing transport models may be improved by including physical phenomena that govern fluid flow at the pore scale. In particular, thermodynamic arguments suggest that hysteresis...
We have developed a compact micro total analysis system (μTAS) to serve as a platform for in-situ spectrophotometric water quality monitoring. Individual fluidic, optical, and electrical components were designed, developed, and characterized. These components were combined in both an integrated (single lithographic “chip-based” platform) and a modular manner. The microfluidic...
There is significant interest in titanium oxide and germanium-silicon oxide nanocomposites for optoelectronic, photocatalytic, and solar cell applications. The ability of the marine diatom Pinnularia sp. to uptake soluble metal oxides from cell culture medium, and incorporate them into the micro- and nano-structure of their amorphous silica cell walls, called...