Engineering Commons^™

Seasonal Change In Bacteria Levels And Eluent Comparison For The Enumeration Of E. Coli And Enterococci From Recreational Beach Sand, Kyle Hines

Theses and Dissertations

Research into the causes of bacterial contamination of recreational beaches has been increasing. Many researchers are now looking to enumerate bacteria from beach sands in order to find the connections between the water and sand quality. As the number of these studies increase, there is a need to determine a standard procedure for enumerating bacteria from sand. The eluent that a researcher chooses could impact the results that they obtain due to ionic strength. The first part of this paper compares the E. coli and Enterococci counts of identical sand samples using phosphate buffered saline and distilled water as eluents. …

Development Of Novel Bioelectrochemical Systems For In Situ Nitrate Removal From Groundwater, Yiran Tong

Theses and Dissertations

This study aims to develop new approaches for in situ nitrate removal from groundwater by using bioelectrochemical systems (BES). BESs employ bioelectricity generated from organic compounds to drive nitrate moving from groundwater into the electrode chamber and reduce nitrate to nitrogen gas by heterotrophic denitrification. In first phase experiments, nitrate ions were driven into the anode chamber of a de-coupled reactor, whose electrode chambers were separated, where heterotrophic denitrification took place with organic reduction. It was proved that by applying additional electrical potential at 0.8V, the reactor could achieve highest removal rate of 208.2±13.3 g NO3--N/m3/d, when initial nitrate concentration …

Mechanical Properties And High-Temperature Performance Of A Polyester Resin Modified Using Fgd Gypsum, Morteza Janbaz

Theses and Dissertations

High-temperature performance of polyester- based construction materials is an important consideration when fire safety is a concern. These materials are typically used as non-structural components of buildings and other structures. Structural retrofits using fiber-reinforced polymer (FRP) composites are also gaining popularity. However, a major disadvantage of polymer- based materials (including FRP composites) is their flammability and toxic gas generation at high temperatures. The main objective of this research effort was to determine the mechanical properties and high-temperature performance of a polyester resin modified with various amounts of an industrial by-product additive. The additive used was Flu-Gas Desulfurization (FGD) gypsum, which …

Recovering Bioresources From Integrated Photo-Bioelectrochemical System, Li Xiao

Theses and Dissertations

Compared to traditional wastewater treatment technologies, the electricity generation is one of the most important advantages of bioelectrochemical systems (BES). However, due to its high cost and low energy production, BES technologies are still far away from feasible application. The main purpose of this work was to investigate ways to improve the electricity generation and reduce the cost of BES technologies. We focused on microbial fuel cells (MFCs) and microbial electrolysis cells (MECs) as two representative BES technologies. In order to improve the energy performance of MFCs, an accurate evaluation of the energy is necessary. However, the common evaluation methods …

Investigation Of Application Niche For Sustainable Wastewater Treatment Using Microbial Fuel Cells, Patrick Thomas Kelly

Theses and Dissertations

Microbial fuel cells represent a sustainable wastewater treatment technology due to its simultaneous treatment of contaminants and electricity production. Selection of suitable substrates is important to identifying proper application of microbial fuel cell (MFC) technology. In this work, four identical MFCs were used to treat the wastes sampled from different stages of a cheese wastewater treatment process, and both treatment performance and energy balance were examined. The two MFCs treating liquid wastes achieved more than 80% removal of total chemical oxygen demand (TCOD), while the other two MFCs fed with sludge or cheese whey removed about 60% of TCOD. The …

Sediment Microbial Fuel Cell As Sustainable Power Resource, Ananta Kothapalli

Theses and Dissertations

This research demonstrates that Ceratophyllum demersum a root less non vascular aquatic plant has negatively affected the power generation from a Sediment Microbial Fuel cell (SMFC). In SMFC the reduced organic matter in the sediment in water produces electrons, which reduces oxygen. Whereas in Plant SMFC continuous supply of organic matter to the anode is done by rhizodeposition (root exudates). Six SMFCs were run for more than 3 months to see the effect of plants, pH and temperature on power generation. Out of six only two SMFC showed stable data. The maximum power density 18 ± 1mW/m3 was generated from …

The Effectiveness Of Silane And Siloxane Treatments On The Superhydrophobicity And Icephobicity Of Concrete Surfaces, Sunil M. Rao

Theses and Dissertations

Icy roads lead to treacherous driving conditions in regions of the U.S., leading to over 450 fatalities per year. De-icing chemicals, such as road salt, leave much to be desired. In this report, commercially available silane, siloxane, and related materials were evaluated as solutions, simple emulsions, and complex emulsions with incorporated particulates, for their effectiveness as superhydrophobic treatments. Through the development and use of a basic impact test, the ease of ice removal (icephobicity) was examined as an application of the targeted superhydrophobicity.

A general correlation was found between icephobicity and hydrophobicity, with the amount of ice removed on impact …

Using Bioelectrochemical Systems For Sustainable Desalination, Bo Zhang

Theses and Dissertations

Desalination of seawater or brackish water holds the potential to solve the freshwater shortage that is threatening nearly half of the world population. Current desalination technologies are energy intensive, which makes the desalinated water prohibitively expensive. In this study, investigations have been made to use renewable energy sources from organic waste to power the desalination process. Since desalination is driven by renewable energy, such desalination systems are more sustainable than currently wide employed commercial technologies. Efforts have been made to study how to operate BES driven desalination process such that the energy consumption will be minimized. Forward osmosis technology is …

Aqueous Turbulence Structure Immediately Adjacent To The Air - Water Interface And Interfacial Gas Exchange, Binbin Wang

Theses and Dissertations

Air-sea interaction and the interfacial exchange of gas across the air-water interface are of great importance in coupled atmospheric-oceanic environmental systems. Aqueous turbulence structure immediately adjacent to the air-water interface is the combined result of wind, surface waves, currents and other environmental forces and plays a key role in energy budgets, gas fluxes and hence the global climate system. However, the quantification of turbulence structure sufficiently close to the air-water interface is extremely difficult. The physical relationship between interfacial gas exchange and near surface turbulence remains insufficiently investigated. This dissertation aims to measure turbulence in situ in a complex environmental …

Establishing And Understanding The Electron Balance In Microbial Fuel Cells, Fei Zhang

Theses and Dissertations

Microbial fuel cells (MFCs) have been intensively studied in the past decade as a promising alternative wastewater treatment technology. However, the critical mass balances such as carbon (or electrons) balances have not well addressed before. Clear understanding of a carbon balance in the anode of an MFC will help to identify electron distribution among different electron acceptors, and the limiting factors that divert electrons from electricity generation. In this study, the effect of substrate loading rate, sulfate, temperature, substrate type and nitrate concentration on MFC's performance were investigated. At different operation condition, the biomass, current, biogas, dissolved oxygen, sulfate and …

The Role Of Solution Chemistry And Cell Surface Properties In Mediating Bacterial Transport And Deposition In Porous Media And Interactioin With Nanomaterials, Lixia Wang

Theses and Dissertations

Groundwater is an important source for drinking water supply. Microbial contaminants have been implicated in two-third of the waterborne disease outbreak. Understanding the fundamental processes, the governing factors and the interfacial interactions that contribute to the deposition of microbial contaminants to porous media will help to elucidate the microbial attachment/transport profile and is highly needed for bioremediation in the environment as well as water purification industry.

In this study, the effects of (1) chemical factors including ionic strength, pH and concentration of phosphate, (2) biological factors including lipopolysaccharide (LPS), biofilm and biofilm extracellular polysaccharide (EPS), and strain type on E.coli …

Travel Time In Macroscopic Traffic Models For Origin-Destination Estimation, Eric Youngblom

Theses and Dissertations

Transportation macroscopic modeling is a tool for analyzing and prioritizing future transportation improvements. Transportation modeling techniques continue to evolve with improvements to computer processing speeds and traffic data collection. These improvements allow transportation models to be calibrated to real life traffic conditions. The transportation models rely on an origin-destination (OD) matrix, which describes the quantity and distribution of trips in a transportation network. The trips defined by the OD matrix are assigned to the network through the process of traffic assignment. Traffic assignment relies on the travel time (cost) of roadways to replicate route choice of trips between OD trip …

Role Of Surface Macromolecules And Solution Chemistry On Bacterial Adhesion To Sand, Lulu Tian

Theses and Dissertations

Bacterial deposition in porous media is of great importance in a number of environmental processes such as bioremediation, water treatment and pathogenic contamination. Pseudomonas aeruginosa (P. aeruginosa) is a ubiquitous Gram-negative bacterium in the environment, which is able to cause disease particularly to susceptible individuals. It has been widely used as a model microorganism to study biofilm formation and Extracellular Polymeric Substances' (EPS) influences. In this work, properties of Lipopolysaccharide (LPS) mutant ÄwaaL, EPS mutants Äpel, Äpsl, Äpel/psl of P. aeruginosa PAO1, such as zeta potential, contact angle, and hydrophobicity were determined. Packed column experiments, and Quartz Crystal Microbalance with …

A Rapid Construction Technique For Bridge Abutments Using Controlled Low Strength Materials (Clsm), Vahid Alizadeh

Theses and Dissertations

The required time for building bridge abutments is one of the key obstacles facing rapid bridge construction. For typical span bridges, this can be remedied by using Controlled Low Strength Materials (CLSM) as backfill materials placed behind full-height precast concrete panels that are integrated with the CLSM backfill via steel anchors. CLSM bridge abutments can be constructed in a short time as they do not require heavy machinery for excavation, compaction, and piling equipment. The main objective of this study was to examine the behavior of an instrumented laboratory large-scale CLSM bridge abutment with full-height precast concrete panels that was …

An Integrative Investigation Of Sources, Fate, And Transport Of Bacteria In Milwaukee Coastal Beaches, Marcia R. Silva

Theses and Dissertations

Beach water quality criteria are determined by the Environmental Protection Agency (EPA) and water quality advisories or closings are issued based on fecal indicator bacteria (FIB) at the beaches. Understanding of sources, fate and transport of FIB at a beach environment is of economic and social interest for public users, beach managers, policy makers and scientists. This is a complex problem and it is a multidisciplinary issue by nature. Scientists have generally taken a reductionist approach to tackle complex environmental issues. However, as alluded by Gallagher and Appenzeller (1999) and adopted by Boehm (2000), many complex systems are best interpreted …