University of Vermont

Civil & Environmental Engineering

Environmental and Public Health

Research Project: Biofouling Mechanisms of Surface-modified Ultrafiltration Membranes During Wastewater Treatment

PI: Huijie Lu (Civil and Environmental Engineering, UVM)

Co-PI: Raju Badireddy (Civil and Environmental Engineering, UVM)

Students Involved: Students involved: Mengfei Li

Description: The recently developed bismuth dimercaptopropanol nanoparticles (BisBAL NP) are capable of outperforming commercially available antibiotics such as chlorhexidine, nystatin, and terbinafine in biofilm control. BisBAL NPs also appear to be more effective than other nanoparticles (e.g., silver NPs) in enhancing antifouling capacities of ultrafiltration membranes, mainly due to their lower minimal inhibitory concentrations (MIC) for typical biofouling microorganisms. This study aimed at examining the microbial ecology of biofouling processes occurring on both commercial ultrafiltration membranes (not surface modified), and the novel, BisBAL NP-modified membranes. By depicting a more comprehensive and detailed picture of the biofouling mechanisms, this study can potentially inspire more efficient anti-fouling strategies for membrane-based wastewater treatment.

Publications:

Badireddy, A., et al. (2014). "Synthesis and characterization of lipophilic bismuth dimercaptopropanol nanoparticles and their effects on oral microorganisms growth and biofilm formation." Journal of Nanoparticle Research 16(6): 1-12.

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Tailpipe Emissions from Light-Duty Engines Operating on Alternative Fuels: Is Biodiesel Really Better?

PI: Britt A. Holmén

Co-PI: Naomi K. Fukagawa

Graduate Students Involved: John Kasumba (Ph.D.), Tyler Feralio (Ph.D.) , Jim Dunshee (M.S.)

Description: Depleting fossil fuel reserves, energy security and climate change concerns have increased use of biomass-based fuels worldwide, but little is known about the ultrafine and nanoparticles and gas-phase air toxics emitted when operating on biodiesel fuel blends. Using a Volkswagen light-duty diesel engine that operates on a transient drive cycle, we measure tailpipe exhaust and engine parameters at 1Hz resolution to answer the following questions in this interdisciplinary research collaboration:

  1. How does particle- and gas-phase exhaust composition change with engine operating parameters and biodiesel fuel blend?
  2. Are the health effects of biodiesel better or worse than for petroleum diesel?
  3. Are biodiesel particles more or less reactive to ozone and are the oxidation products more or less likely to increase particle toxicity?
  4. How does exhaust particle size and organic chemical composition vary among blends of two biodiesel fuels (soybean and recycled cooking oil)?

Example Research Presentations

Dunshee, Jim and Britt A. Holmén (2014) Measured and Modeled Biodiesel Exhaust from Diesel Vehicles: A MOVES2010b Evaluation. Paper 8CO.1, American Association for Aerosol Research 33nd Annual Conference, October 20-24, Orlando, FL.

Feralio, Tyler and Britt A. Holmén (2014) Effect of Drive Cycle and Fuel Type on Ultrafine Particle Number Emissions Model Input Optimization. 93rd Annual Meeting of the Transportation Research Board, January 2014, Washington, DC. Paper No. 14-4588.
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Feralio, Tyler and Britt A. Holmén (2014) Light-Duty Diesel Biodiesel Particle Number Emissions Relative to Blend Ratio and Engine Conditions, Paper 8CO.7, American Association for Aerosol Research 33nd Annual Conference, October 20-24, Orlando, FL.

Kasumba, John and Britt A. Holmén (2014) Oxidation of Biodiesel Exhaust Particulate Matter with Ozone. Paper 2AC.7, American Association for Aerosol Research 33nd Annual Conference, October 20-24, Orlando, FL.

Publications

Fukagawa, Naomi K., Muyao Li, Matthew E. Poynter, Brian C. Palmer, Erin Parker, John Kasumba and Britt A. Holmén (2013) Soy Biodiesel and Petrodiesel Emissions Differ in Size, Chemical Composition and Stimulation of Inflammatory Responses in Cells and Animals. Environmental Science & Technology 47 (21), 12496–12504. 10.1021/es403146c

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Contaminant Transport in Building Materials

PI: Mandar Dewoolkar (Civil and Environmental Engineering, UVM)

Co-PI: Donna Rizzo and Nancy Hayden

Graduate Students Involved: Cabot Savidge, David Grover and Lucas Howard

Description: We are studying contaminant transport through porous building materials. We are using techniques such as X-ray tomography, surface permeability mapping and fluorescent confocal microscopy to quantify geomorphic structures of building materials such as sandstone, limestone, concrete and brick. A numerical model is being calibrated using the above data and physical transport experiments. This study supports an overarching goal of understanding fate and transport of chemical agents in porous materials used in heritage and essential facilities, so appropriate decontamination strategies could be developed. This research has been funded by the Los Alamos National Laboratory and Defense Threat Reduction Agency.


Publications:
Hu, L., Savidge, C., Rizzo, D., Hayden, N. Hagadorn, W., and Dewoolkar, M. (2013), “Commonly used porous building materials: geomorphic pore structure and fluid transport”, Journal of Materials in Civil Engineering, 25(12), 1803-1812.

Savidge, C. R., Hu, L. B., Hayden, N. J., Rizzo, D., and Dewoolkar, M. M. (2008), “Variability in surface permeability of porous building substrates and their implications on transport of agents”, Chemical and Biological Defense Physical Science and Technology Conference, New Orleans, LA, November. (Oral presentation)

Hu, L. B., Savidge, C. R., Brownell, M., Hayden, N. J., Rizzo, D., and Dewoolkar, M. M. (2008), “Prediction of agent transport in porous building materials”, Chemical and Biological Defense Physical Science and Technology Conference, New Orleans, LA, November. (Oral presentation)

Last modified April 24 2015 02:03 PM