Polymer thin films for applications in water sensing and treatment

Date: 4/30/2021

Speaker: Dr. Matthias J. Young (Moderated by Dr. Baolin Deng)

Bio: Dr. Matthias J. Young is an assistant professor at the University of Missouri Columbia (MU) with a joint appointment in the Biomedical, Biological, and Chemical Engineering Department and the Department of Chemistry. Dr. Young holds a B.S from MU and a Ph.D. from the University of Colorado Boulder, where he was an NSF GRFP recipient. Prior to joining the faculty at MU, Dr. Young was an NRC postdoc at the National Institute of Standards and Technology, and a postdoctoral appointee at Argonne National Laboratory. Dr. Young’s work focuses on the intersection of thin film coating chemistry and the study if electrochemical material properties. Current research projects in his research group focus on understanding and improving electrode materials for energy storage and water treatment applications. Dr. Young is the recipient of the 2020 Paul H. Holloway Young Investigator Award from the American Vacuum Society Thin Film Division and is author on > 20 publications and inventor on 5 patent applications.

Abstract: To protect our local water supplies and ensure a supply of clean water to people around the world, we need improved technologies for detecting and removing ions in water. For example, we need low-cost sensors for measuring nutrient anions (e.g. nitrate and phosphate) in water to aid in improving agricultural practices. And we need more energy-efficient desalination technologies to make seawater desalination viable in coastal communities around the world. Electrochemical technologies are among the most promising approaches for these applications, but are not at a sufficient technology readiness level for deployment. The performance of electrochemical devices for these applications is driven by the electrochemically active materials used in the devices. New materials are needed to provide improved performance and address these pressing needs in the water space. Here, we describe efforts in our group to understand how the thickness, structure, and composition of redox-active polymers impact performance for applications in the water space. We report on our recent work studying the electrochemistry of thin film polyaniline, and establishing a new instrument for understanding electrochemical properties of thin films. We also describe our current efforts to employ molecular layer deposition (MLD) to form thin-film polymer electrodes that bind ions at a high rate for use in electrochemical water desalination, and on work to alter the structure of these polymer thin-films to make them selective toward target ions for sensing applications. We identify new insights into the electrochemical properties of polymer films, and identify next steps for advancing these polymer materials to improve water-relevant technologies.

Integrating hydrodynamics into ecosystem studies

Date: 4/16/2021

Speaker: Dr. Brandon Sansom (Moderated by Dr. Baolin Deng)

Bio: Brandon Sansom is a research engineer in the River Studies Branch at the U.S. Geological Survey – Columbia Environmental Research Center working on transport phenomena in riverine ecosystems. His research focuses on organism-flow interactions, how these interactions contribute to the structure and function of river ecosystems, and how improved understanding of organism-flow interactions can aid aquatic ecosystem conservation and management efforts. Current research projects include: 1) predicting freshwater mussel eDNA transport and fate, and 2) characterizing and quantifying pallid sturgeon age-0 dispersal. He has received a B.A. from Washington and Jefferson College, a M.S. from the University of Oklahoma, and a Ph.D. from SUNY Buffalo .

Abstract: The structure and function of aquatic ecosystems are largely controlled by the interactions of biological, physical, and chemical processes across multiple scales. While developments in aquatic ecology have encompassed many research foci (e.g., eco-hydrology, eco-geomorphology, etc.) and exciting findings are being found at the interfaces of these disciplines, ecologists still lack an understanding of how organisms have evolved and adapted to exploit natural flow conditions. Previous researchers have predicted that incorporating fluid dynamics into ecosystem studies would greatly advance ecological theory. My research combines field studies, laboratory experiments, and computational fluid dynamic modeling to investigate transport phenomena in rivers and how organism-flow interactions contribute to river form and function. In this talk, I will demonstrate 1) how freshwater mussels modify near-bed turbulent flow through passive and active organism-flow interactions and 2) the usefulness of numeric and hydrodynamic models in predicting the fate and transport of environmental DNA. Moreover, I will discuss the framework for using transport phenomena to investigate the dispersal of age-0 pallid sturgeon. Ultimately, the results of this research help to improve the conservation and management of aquatic species and ecosystems.

Flint Water Crisis: The Road to Hell is Paved with Good Intentions

Date: 3/19/2021

Speaker: Dr. Susan Masten (Moderated by Dr. Baolin Deng)

Bio: Susan Masten is a Professor in the College of Engineering at Michigan State University. Professor Masten's research has involved the use of chemical oxidants for the remediation of soils, water, and leachates contaminated with hazardous organic chemicals. She has conducted research on the in-situ use of gaseous ozone to oxidize residual contaminant in saturated soils using ozone sparging and in unsaturated soils using soil venting. Dr. Masten has evaluated the toxicity of the by-products of chemical oxidation processes as measured by gap junction intercellular communication. Work focused on the ozonation and chlorination of several pesticides, including atrazine, alachlor, and lindane and on the PAHs, especially pyrene. Dr. Masten’s research involves the use of ozone-ceramic membrane filtration for the treatment of drinking waters containing organic matter and emerging contaminants. She has published over 100 publications and graduated over 50 MS students and 14 Ph.D students.

Abstract: Much has been written about the Flint Water Crisis since the source water for the City of Flint was switched from Lake Huron to the Flint River on April 26, 2014. Elevated levels of lead found in the drinking water of residences in Flint, MI are well documented, as are issues related to the health and well-being of Flint’s residents. In this talk, we will look at the Flint Water Crisis from the perspective of the engineering and chemistry of the treatment processes and the distribution system. We will also investigate how historical policy decisions played a role in the crisis and what we as engineers can learn to ensure that this never happens again, in Flint and elsewhere.

Drought dynamics: From Plant Responses to Regional Land-Atmosphere Feedbacks

Date: 3/5/2021

Speaker: Dr. Jeff Wood (Moderated by Dr. Binbin Wang)

Bio: Jeff is an Assistant Professor of Biometeorology. He received his PhD in Land Resource Science from the University of Guelph in Canada, and conducted postdoctoral research at the University of Minnesota before joining the University of Missouri in 2016. His ecosystem science research program focuses on biosphere-atmosphere interactions and understanding process along root-to-shoot and leaf-to-landscape continuums, with emphasis on ecosystem functional responses to water stress. Current research emphasis areas include ecosystem hydraulics, canopy photosynthesis/sun-induced chlorophyll fluorescence (SIF) and ecosystem to regional greenhouse gas budgets. He collaborates with scientists from diverse disciplines including plant physiology and ecology, soil physics, atmospheric science, remote sensing, as well as ecosystem modeling. Recently, he started collaborating with aquatic ecologists and environmental engineers to develop research aimed at understanding the coupled terrestrial and aquatic carbon cycles.

Abstract: Drought occurs on a broad range of spatial and temporal scales, and as a consequence, has myriad impacts on food, water and natural resources as well socio-economic systems. Drought is distributed across nearly all regions of the world and is thus one of the most important factors limiting global productivity. Flash droughts are particularly challenging because they develop quickly over a relatively short time period (weeks to months), yet can still have severe consequences on ecosystems and society. The agricultural and natural ecosystems supporting life on Earth through the provisioning of food, fiber, fuel, and numerous ecosystem services, are likely to face intensifying drought pressures. Understanding ecosystem functional responses to drought is therefore crucial for accurate coupled climate and carbon cycle predictions and developing strategies for risk management. We analyzed the flash (extreme) drought of 2012 within the context of a natural dry-down experiment to elucidate ecosystem functional dynamics at daily to seasonal time scales in a Quercus-Carya (oak-hickory). We synthesized measurements of ecosystem carbon dioxide and water vapor exchanges, predawn leaf water potential (Ψpd) and soil respiration (RS) to answer the following questions: 1) How does gross primary productivity and evapotranspiration vary in response to a flash drought-recovery sequence? 2) How do light-use and water-use efficiencies vary through a flash drought-recovery sequence? and 3) Is there evidence of a land feedback on the atmosphere that intensified drought?