Environmental Engineering Commons^™

Computer Modeling Of Close-To-Ground Tornado Wind-Fields For Different Tornado Widths, Mohammadhossein Kashefizadeh

Graduate Theses and Dissertations

Tornadoes induce different wind forces on buildings than straight-line (SL) winds. The tangential velocity (Vθ) of tornados is the main parameter that causes damage to the buildings. In-field tornado measurements cannot evaluate the tornado’s Vθ at less than 20m above ground level (AGL). The laboratory tornado simulators suggest that the Swirl ratio (S) and the radius (ro) are the most influential factors affecting Vθ. However, due to scaling problems, laboratory simulators cannot report the Vθ for elevations less than 10m AGL. Well refined computational fluid dynamics (CFD) models can evaluate the Vθ at less than 10m AGL. However, the CFD …

Electrochemical Microsensors For In Situ Monitoring Of Chemical Compounds In Engineered And Natural Aquatic Systems, Jared Church

Electronic Theses and Dissertations

The adaption of needle-type electrochemical microsensor (or microelectrode) techniques to environmental science and engineering systems has transformed how we understand mass transport in biotic and abiotic processes. Their small tip diameter (5-20μm) makes them a unique experimental tool for direct measurements of analytes with high spatial and temporal resolutions, providing a quantitative analysis of flux, diffusion, and reaction rate at a microscale that cannot be obtained using conventional analytical tools. However, their applications have been primarily limited to understanding mass transport dynamics and kinetics in biofilms. With the advancement of sensor fabrication and utilization techniques, their potential applications can surpass …

Design And Analysis Of A Parabolic Trough Solar Concentrator, George N. Skouras

Master's Theses

A prototype solar desalination system (SODESAL) with a parabolic-trough solar concentrator (PTSC) and evacuated tube was designed and analyzed to determine the solar thermal capabilities for small-scale distillation and energy generation. A proof-of-concept study verified that distillation is possible with the system as designed, however a rupture occurred in the copper heat-pipe heat exchanger due to overheating. The internal temperatures of an aluminum heat transfer fin were measured inside an evacuated tube typically used in solar water heater systems to understand the lateral heat distribution and identify possible causes of the rupture. Solar radiation was measured for both the summer …

Cover Crops Have Negligible Impact On Soil Water In Nebraska Maize–Soybean Rotation, J. Burdette Barker, Derek M. Heeren, Katja Koehler-Cole, Charles Shapiro, Humberto Blanco-Canqui, Roger W. Elmore, Christopher A. Proctor, Suat Irmak, Charles A. Francis, Tim M. Shaver, Ali T. Mohammed

Department of Agricultural and Biological Systems Engineering: Faculty Publications

One perceived cost of integrating winter cover cropping in maize (Zea mays L.) and soybean [Glycine max (L.) Merr.] rotation systems is the potential negative impact on soil water storage available for primary crop production. The objective of this 3-year study was to evaluate the effects of winter cover crops on soil water storage and cover crop biomass production following no-till maize and soybean rotations. Locations were near Brule (west-central), Clay Center (south-central), Concord (northeast), and Mead (east-central), Nebraska, United States. Treatments included crop residue only (no cover crop) and a multi-species cover crop mix, both broadcast-seeded before …

Comparison Of A Modified And Traditional Rapid Infiltration Basin For Treatment And Control Of Nutrients In Wastewater Effluent, Jessica Cormier

Electronic Theses and Dissertations

Rapid infiltration basins (RIB) have been historically used in Florida for groundwater recharge, effluent disposal, or a combination of both. However, this technique has proven ineffective in providing nitrogen control unless the RIB is modified in some manner. In this study, a traditional RIB was compared to a modified RIB constructed with manufactured biosorption activated media (BAM) to evaluate nitrate removal from reclaimed water. The RIBs are used for reclaimed and excess storm water disposal. Few, if any, studies have been published where BAM-modified RIBs have been used for this purpose. In this work, a mixture of clay, tire crumb, …

Nanofiltration Of Perfluorinated Compounds As A Function Of Water Matrix Properties, Hadi Toure

Electronic Theses and Dissertations

Perfluorinated compounds (PFCs) have been manufactured and used in various industries including food packaging, paintings, and coating industries. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are the most commonly investigated PFCs that have bioaccumulative properties and a strong persistence in environment. Despite the growing interest in using membrane technology to remove PFOA and PFOS from water, little information is available on the impact of natural water matrices on the removal of PFOA and PFOS when using nanofiltration (NF). The presence of natural organic matter (NOM) and cations (Ca2+ and Mg2+) in water matrices and their interactions with the PFCs …

Human-Centered Design Of An Air Quality Feedback System To Promote Healthy Cooking, Chantal Iribagiza

Dissertations and Theses

Household air pollution (HAP) is responsible for almost 4 million premature deaths every year, a burden that is primarily carried by women and children in developing countries. The mortality and morbidity impact of HAP can be significantly alleviated through clean cookstove interventions. However, for these interventions to be effective, the new intervention stove must be a substantially cleaner technology and adoption should be high and sustained over time.

Woody biomass is the fuel of choice in many developing communities, and contributes substantially to HAP. Several organizations have launched clean cooking interventions to address this issue. However, the majority of those …

My Catalyst, Gabrielle Gambino Lyon

Celebration of Learning

Over the course of my internship and shadow program with Pepper Lawson Construction and Ziegler Cooper Architects, I was able to explore the various career paths involved in the design, construction, and civil engineering fields. My work on the construction site of a high-rise apartment building located in the heart of Houston, TX allowed me first-hand experience working and learning alongside project engineers, contractors, building developers, and the construction team.

This project was the perfect confluence of my main areas of interest: structural, mechanical, civil, and environmental engineering, as well as architecture. My daily work consisted of on-site walk throughs, …

Plant Community Composition, Floristic Quality, And Establishment Of Roadside Revegetation In Nebraska, Usa, Jonathan M. Soper

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Roadside revegetation poses a challenge and opportunity for biodiversity conservation, as the land area occupied by roadsides is not expected to decline in the future. In the context of roadside revegetation activities in rural regions dominated by agricultural land uses, revegetation efforts can establish plant communities that offer unique species that would otherwise be absent on the landscape. To determine the efficacy of roadside revegetation efforts in 1) providing plant communities of high biodiversity value and 2) meeting the expectations of roadside revegetation managers for establishment, we quantified botanical composition, floristic quality, and success in seeding efforts to meet manager …

Dna Identification Of Polyculture, Andrew Schuler

Energize New Mexico (NSF EPSCoR Track 1 IV)

DNA sequencing of algae polyculture growing in oilfield produced water. It is dominated by the algae species Parachlorella kessleri and Cyanobacterium aponinum.

Evaluation Of Effectiveness Of Streambank Stabilization Practices And Flood Impact On Cedar River, Nebraska, Naisargi N. Dave

Department of Environmental Engineering: Theses and Other Student Research

Stream restoration has been a major environmental objective for preserving biodiversity, reducing loss of valuable cropland and improving water quality. The impact and efficiency of streambank stabilization practices has been simulated using erosion-prediction models; however, evaluation of the erosion-control practices to measure their efficiency is often neglected. This project monitored changes in fluvial geomorphology on the Cedar River in Nebraska and quantified the effectiveness of 18 sites with streambank stabilization practices. A flood event in 2010 due to dam failure acted as a major parameter in measuring the efficiency of the erosion control practices. The methodology included aerial imagery to …

Characterizing Patterns In E. Coli Levels In Rio Grande River Water And Riverbed Sediments Near Albuquerque, Nm, James Fluke

Civil Engineering ETDs

In this work I examined how Fecal indicator Bacteria (FIB) behave in a large environmental system (Rio Grande near Albuquerque, ~60 km distance). I addressed the questions: How do FIB levels in river water and riverbed sediments of this reach change with distance along the river and throughout one year?

I conducted year-round river water and sediment sampling for concentration of E. coli bacteria, a persistent contaminant in the area. I found that over the year, E. coli loading in river water increased along the 60 km reach and E. coli in the sediments mainly increased near the Albuquerque urban …

Metal Reactivity In Laboratory Burned Wood From A Watershed Affected By Wildfires, Asifur Rahman

Civil Engineering ETDs

Massive amounts of wood ash are deposited into nearby streams as a result of runoff from storm events after increasing frequency of wildfire events that negatively affect water quality. Ash and debris from burned vegetation can alter the pH, turbidity and dissolved oxygen (DO) in water and can release heavy metals, organic matter, and nutrients. We investigated interfacial processes affecting metal mobility in wood ash burned under laboratory-controlled conditions using aqueous chemistry, microscopy and spectroscopy analyses. Wood was collected from the Valles Caldera National Preserve in New Mexico which has experienced two wildfires since 2011 that have caused devastating effects. …

Huron-To-Erie Water Quality Data Platform, Lanyu Xu, Carol J. Miller, James Olson, Michael Beaulac

Civil and Environmental Engineering Faculty Research Publications

To address the challenges of environmental degradation, creation of a sustainable urban environment, and increased public engagement and awareness, a mass-oriented, user-friendly and cloud-based data platform has been developed and deployed to provide integrative water quality data in one of the most critical urban corridors of the Laurentian Great Lakes system. In this paper, we describe the data platform developed for the watershed and connecting channels between Lake Huron and Lake Erie, including the St. Clair River, Lake St. Chair, and the Detroit River. This data platform greatly facilitates the access of data across data providers and agencies. Several example …

Cross Photoreaction Of Glyoxylic And Pyruvic Acids In Model Aqueous Aerosol, Sha-Sha Xia, Alexis J. Eugene, Marcelo I. Guzman

Chemistry Faculty Publications

Aerosols of variable composition, size, and shape are associated with public health concerns as well as with light-particle interactions that play a role in the energy balance of the atmosphere. Photochemical reactions of 2-oxocarboxylic acids in the aqueous phase are now known to contribute to the total secondary organic aerosol (SOA) budget. This work explores the cross reaction of glyoxylic acid (GA) and pyruvic acid (PA) in water, the two most abundant 2-oxocarboxylic acids in the atmosphere, under solar irradiation and dark thermal aging steps. During irradiation, PA and GA are excited and initiate proton-coupled electron transfer or hydrogen abstraction …

The Effect Of Destoning And Enzymatic Pretreatments On The Biofuel Production From Olive Cake, Patrick Tai

Master's Theses

More than 16,000 tons of olive cake was produced in the United States in 2017. Olive cake is a by-product of olive oil extraction, which has limited animal feed potential, and poses an environmental threat when landfilled due to its high organic load and polyphenol content. This residue has potential for biofuel (bioethanol and biomethane) production because it is rich in polysaccharides such as pectin, hemicellulose, and cellulose. Yet, olive cake contains olive stones that can impede its conversion to biofuel. Therefore, two methods of destoning, centrifugation and screening by horizontal screw press, were first compared. Both methods removed an …

Evaluating Opportunities And Barriers To Improving The Energy Efficiency Of Small Nebraska Wastewater Treatment Plants, Matthew J. Thompson

Department of Environmental Engineering: Theses and Other Student Research

Wastewater treatment plants (WWTP)s account for about 0.8% of U.S. electricity use. Small WWTPs serving communities of populations less than 10,000 accounts for 95% of treatment plants in Nebraska. These plants are significantly less efficient compared to large systems and thus improving their energy efficiency (E2) is a growing focus in efforts to reduce greenhouse gas emissions associated with their operation. Energy use of plant unit operations was evaluated for several plants and included analysis of energy for space heating. Specific infrastructure and/or operational changes reported by operators following an E2 benchmarking project were evaluated by quantifying the change in …

A 3d Model For Earthquake-Induced Liquefaction Triggering And Post-Liquefaction Response, Arash Khosravifar, Ahmed Elgamal, Jinchi Lu, John Li

Civil and Environmental Engineering Faculty Publications and Presentations

A constitutive soil model that was originally developed to model liquefaction and cyclic mobility has been updated to comply with the established guidelines on the dependence of liquefaction triggering to the number of loading cycles, effective overburden stress (Kσ), and static shear stress (Kα). The model has been improved with new flow rules to better capture contraction and dilation in sands and has been implemented as PDMY03 in different computational platforms such as OpenSees finite-element, and FLAC and FLAC3D finite-difference frameworks. This paper presents the new modified framework of analysis and describes a guideline to calibrate the input parameters of …

Impact Of Recirculating Nitrified Effluent On The Performance Of Passive Onsite Hybrid Adsorption And Biological Treatment Systems, Amulya Miriyala

USF Tampa Graduate Theses and Dissertations

Approximately 25% of households in the U.S. treat their wastewater onsite using conventional onsite wastewater treatment systems (OWTS). These systems typically include a septic tank or a series of septic tanks followed by a soil absorption system. They effectively remove biochemical oxygen demand (BOD), total suspended solids (TSS), fats and grease but are not designed to remove significant amounts of nitrogen. High nitrogen loading to coastal and ground waters can be dangerous to aquatic life and public health. Hence, there is a need for advanced onsite wastewater treatment systems that can effectively remove nitrogen. Making enhanced nitrogen removal for OWTS …

Comparative Study Of One Parameter Budyko Model Index And The Scs Curve Number, Cihad Ayberk Doner

LSU Master's Theses

This study investigates two water balance models from different levels of complexity to recognize the impacts of climate change on water resources. The main objective is to examine the capacity of future runoff calculations of a parsimonious simple water balance model compared to a more complex model under the climate change variables. The selected water balance models are the simple one-parameter Budyko-type model using the Zhang’s equation with single parameter (a) and the more complex model (HELP3) applying Soil Conservation Service (SCS) curve number method to calculate future runoff predictions. The study has a twofold focus, first on explaining the …