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Performance Comparison Of Low-Cost Sensors Across Six Cities Of Continental United States, Md Hasibul Hasan
Performance Comparison Of Low-Cost Sensors Across Six Cities Of Continental United States, Md Hasibul Hasan
Electronic Theses and Dissertations, 2020-
In the field of air quality measurement, low-cost sensors have been extensively used for capturing high-resolution spatial and temporal pollutant concentrations. However, data accuracy and the impact of environmental conditions particularly temperature and relative humidity, remain a significant issue. Careful sensor calibrations against reference instruments are necessary for ensuring data accuracy and validity. This study investigated the effectiveness of multiple calibration methodologies (linear calibration, 3rd order polynomial calibration, and Random Forest, RF) for low-cost air quality sensor calibration across six cities (Atlanta, Portland, Riverside, Sacramento, New York City, and Phoenix) in the United States. The data for this study is …
Polyelectrolyte Functionalized Forward Osmosis For Water Reclamation From Synthetic Spacecraft Wastewater, Alina Ripp
Polyelectrolyte Functionalized Forward Osmosis For Water Reclamation From Synthetic Spacecraft Wastewater, Alina Ripp
Electronic Theses and Dissertations, 2020-
This study investigated the application of a polyelectrolyte (PE)-assisted metallic iron nanoparticle-integrated forward osmosis (FO) membrane to treat synthetic spacecraft wastewater comprising urea, ammonium carbonate, and linear alkylbenzene sulfonate (LAS). The draw solution (MgSO4) diluted via the FO operation was further treated using a nanofiltration (NF) membrane aimed at producing potable quality water by the FO-NF hybrid process. A cellulose triacetate FO membrane was functionalized by layer-by-layer deposition of polyallylamine hydrochloride (PAH) and polyacrylic acid (PAA) followed by incorporating zero valent iron nanoparticles (ZVINP) within the "bilayers". It required 14 bilayers to ensure a uniform coating as demonstrated via scanning …
Improving Urban Resilience And Sustainability Via Multi-Scale Urban Food-Energy-Water-Waste Nexus Analysis, Andrea Valencia Marin
Improving Urban Resilience And Sustainability Via Multi-Scale Urban Food-Energy-Water-Waste Nexus Analysis, Andrea Valencia Marin
Electronic Theses and Dissertations, 2020-
Urban sustainable development requires an in-depth and holistic understanding of the complex Food-Energy-Water-Waste (FEWW) nexus facing population growth, climate change, economic development, and pollution control. Following the United Nations (UN) 17 Sustainable Development Goals (SDGs), goal 11 aims for sustainable cities and communities to be resilient, sustainable, and safe cities to achieve social, economic, and environmental sustainability. Explicitly, SDG target 11.3 concentrates on inclusive and sustainable urbanization for sustainable planning and management. As the UN Food System program aims for inclusive, sustainable, and resilient network, promoting sustainable food systems becomes a necessity to echo social, economic, and environmental sustainability. The …
Application Of Biologically Activate Carbon For Treatment Of Sulfide-Laden Groundwater, Jessica Cormier
Application Of Biologically Activate Carbon For Treatment Of Sulfide-Laden Groundwater, Jessica Cormier
Electronic Theses and Dissertations, 2020-
Small-system water purveyors must overcome many challenges to provide an adequate and safe water supply to its consuming public. This dissertation reports on research related to the application of biologically activated carbon (BAC) media filters for the treatment of well water to remove disinfection by-product (DBP) precursor matter, measured as dissolved organic carbon (DOC), at two treatment plants serving a small community water system. Four research questions were investigated individually in discrete, yet interconnected studies at two water treatment facilities processing groundwater that contained hydrogen-sulfide (~1.2 mg/L) and dissolved organic carbon (~2.0 mg/L). The first study revealed that BAC filters …
A Novel Antibody-Dependent Mc-Lr Detecting Biosensor For Early Warning Of Harmful Algal Blooms (Habs), Stephanie Stoll
A Novel Antibody-Dependent Mc-Lr Detecting Biosensor For Early Warning Of Harmful Algal Blooms (Habs), Stephanie Stoll
Electronic Theses and Dissertations, 2020-
Microcystins (MCs) are toxins produced by cyanobacteria commonly found in harmful algal blooms (HAB) occurring in many surface waters. Due to their toxicity to humans and other organisms, the World Health Organization (WHO) set a guideline of 1 µg/L for microcystin-leucine-arginine (MC-LR) in drinking water. However, current analytical techniques for the detection of MC-LR such as liquid chromatography-mass spectrometry (LC-MS) and enzyme-linked immunosorbent assay (ELISA) are costly, bulky, time-consuming, and mostly conducted in a laboratory, requiring highly trained personnel. Therefore, an analytical method that can be used in the field for rapid determination is essential. In this study, an Anti-MC-LR/MC-LR/Cysteamine …
Using Iphone Significant Location Data To Improve Air Pollution Exposure Estimation, Elizabeth Eastman
Using Iphone Significant Location Data To Improve Air Pollution Exposure Estimation, Elizabeth Eastman
Electronic Theses and Dissertations, 2020-
An accurate estimation of human exposure to ambient air pollution is crucial for air pollution health studies. Time-activity patterns may introduce substantial uncertainties in exposure estimation. As smartphones are becoming increasingly popular and their ownership is becoming ubiquitous in the US. Virtually all smartphones can collect location data, and such data is continuously somewhere. Therefore, it is clear that such stored location data has the potential to be used for characterizing an individual's time-activity patterns for air pollution health studies. However, studies on the accuracy and feasibility of using a smartphone's location data in air pollution exposure estimation are still …
The Effects Of Critical Micelle Concentration And Environmental Factors On Oil Separation In Simulated Bilgewater Emulsions, Kelsey Rodriguez Doran
The Effects Of Critical Micelle Concentration And Environmental Factors On Oil Separation In Simulated Bilgewater Emulsions, Kelsey Rodriguez Doran
Electronic Theses and Dissertations, 2020-
Improved bilgewater treatment is necessary because of technological challenges often faced when meeting existing ocean discharge criteria regulations. Since bilgewater is a waste mixture including hydraulic oils, cleaning agents, and seawater, the success of its management is largely attributed to understanding oil-in-water emulsion characterizations. However, the study of bilgewater emulsions is complex due to the multivariate nature of real-shipboard samples. The objective of this study is to develop the relationship between parameters commonly found in bilgewater and emulsion stability. This work is a continuation of a 3-year research project supported by the Strategic Environmental Research and Development Program (SERDP). Previous …
Combining Multivariate Statistical And Numerical Modeling For Coastal Hazards Analysis, Victor Malagon Santos
Combining Multivariate Statistical And Numerical Modeling For Coastal Hazards Analysis, Victor Malagon Santos
Electronic Theses and Dissertations, 2020-
Increased population density along the world's coastlines is driven by the wide range of services provided by costal systems, such as transportation, fisheries, trade, and tourism. Despite offering fundamental services, coastal systems are exposed to a range of natural hazards such as riverine and/or coastal flooding, and erosion, thus robust risk analyses are needed to protect coastal ecosystems, infrastructure, and people dwelling in proximity to the shoreline. Numerical and multivariate statistical models have become crucial tools in coastal risk management to support robust risk analyses, and their combined use provides many benefits in the analysis of coastal hazards. This dissertation …
Evaluating Ozone And Granular Activated Carbon Treatment For Control Of Disinfection By-Product Formation For A Central Florida Groundwater Supply, Devon Higgins
Electronic Theses and Dissertations, 2020-
A pilot investigation that compared ozone oxidation with an integrated ozone and granular activated carbon (GAC) process for the control of regulated disinfection by-products at the University of Central Florida's water plant located at the Orlando campus has been completed. Treatment effectiveness was measured by monitoring the parameters pH, temperature, non-purgeable dissolved organic carbon (DOC), ultraviolet absorbance at a wavelength of 254 nm (UV254), specific ultraviolet absorbance (SUVA), excitation emission matrices (EEMs) and the associated formation of the DBP chemical groups total trihalomethanes (TTHMs) and haloacetic acids (HAAs). Groundwater that contained an average of 2.5 milligrams per liter (mg/L) DOC …
Incinerator Ash Characterization - Implications For Elevated Temperature Landfills, Angel Villarruel-Moore
Incinerator Ash Characterization - Implications For Elevated Temperature Landfills, Angel Villarruel-Moore
Electronic Theses and Dissertations, 2020-
The occurrence of temperatures in municipal solid waste (MSW) landfill gas (LFG) extraction systems in excess of 55°C is a problem that has gained much attention in the solid waste industry, both domestically and globally. Facilities which frequently experience such temperatures are termed Elevated Temperature Landfills (ETLFs), and recent research conducted at the University of Central Florida (UCF) has provided strong evidence that ash, both MSW incinerator ash (MSWIA) and coal combustion ash (CCA), when co-disposed with unburned MSW, provides materials which are able to participate in abiotic exothermic reactions that may lead to the development or sustainment of ETLFs. …
Index-Based Approach With Remote Sensing For The Assessment Of Extreme Weather Impact On Watershed Vegetation Dynamics, Kushan Bellanthudawage
Index-Based Approach With Remote Sensing For The Assessment Of Extreme Weather Impact On Watershed Vegetation Dynamics, Kushan Bellanthudawage
Electronic Theses and Dissertations, 2020-
Spatial technologies such as satellite remote sensing can be used to identify vegetation dynamics over space and time, which play a critical role in earth observations. Biophysical and biochemical features associated with vegetation cover can then be used to elucidate climate change impact such as floods and droughts on ecosystem that may in turn affect watershed-scale water resources management. Unlike single flood or drought event, intermittent extreme weather events may exert more physiological and biological pressures on the canopy vegetation. This study aims to investigate the climate change impacts on canopy vegetation, which occurred from March 2017 to October 2017 …
Investigating The Removal Of Total Trihalomethanes In Tray And Spray Aeration Processes At Two Central Florida Groundwater Treatment Facilities, Zachary Protas
Investigating The Removal Of Total Trihalomethanes In Tray And Spray Aeration Processes At Two Central Florida Groundwater Treatment Facilities, Zachary Protas
Electronic Theses and Dissertations, 2020-
An investigation has been completed that assessed the efficiency of tray and spray aeration processes on the removal of regulated total trihalomethanes (TTHMs) at two publicly owned potable groundwater treatment facilities located in Polk County, Florida: the Providence and Van Fleet water treatment plants (WTPs). Finished water from each of these facilities was fed to a pilot-plant that could be operated as either a tray, spray, or combined configuration. A series of four pilot aerator configurations were tested at each WTP. Test 1 evaluated the tray aerator operated in a recirculated multiple-pass mode. It was shown that three passes across …
The Use Of Physically Based Models And Ensemble Forecasting For Storm Surge Risk Assessment In A Changing Climate, Jeane Camelo
The Use Of Physically Based Models And Ensemble Forecasting For Storm Surge Risk Assessment In A Changing Climate, Jeane Camelo
Electronic Theses and Dissertations, 2020-
Storm surge has been the deadliest and costliest hurricane induced hazard in the coastal United States. In order to save property and lives, emergency managers must issue advisories guided by numerical models in a timely manner. However, these surge models are highly dependent on weather forecasts which contain uncertainties themselves as hurricanes traverse through the waters before making landfall. This dissertation aims to understand the contribution of uncertainties in hurricane properties, particularly the wind intensity which can contribute to uncertainties in storm surge models. Investigating these properties through numerical modeling is both computationally and time intensive. However by developing a …
Evaluating Source Water Quality, Pretreatment, And Particulate Mass Transport In A Nanofiltration Membrane Process, Courtney Powell
Evaluating Source Water Quality, Pretreatment, And Particulate Mass Transport In A Nanofiltration Membrane Process, Courtney Powell
Electronic Theses and Dissertations, 2020-
This document details the source and occurrence of particulates in a nanofiltration (NF) process, considers the implementation of additional pretreatment to improve feedwater quality, and investigates the impact of submicron particles on membrane performance. Much of this research was performed in cooperation with the City of Boynton Beach (City) at the West Water Treatment Plant (WTP) and stemmed from particulate fouling concerns in the pretreatment and NF membrane processes. The water quality of the individual wells that supply the West WTP was evaluated to identify the source of particulates which overload the pre-filters (5-μm cartridge filters) and may contribute to …
The Effect Of Polyelectrolyte Modification Of Ultrafiltration Membranes On Fouling Resistance And Rejection Of Contaminants Of Emerging Concern, Kunal Olimattel
The Effect Of Polyelectrolyte Modification Of Ultrafiltration Membranes On Fouling Resistance And Rejection Of Contaminants Of Emerging Concern, Kunal Olimattel
Electronic Theses and Dissertations, 2020-
This research attempted to leverage the unique properties of poly (allylamine hydrochloride) (PAH)/poly (acrylic acid) (PAA) bilayer coatings to enhance antifouling and antimicrobial properties of a commercially available ultrafiltration (UF) membrane as well as the removal of PFOA and PFOS—the two CECs that most frequently represent the class of PFAS. The effects of selected water matrix components (humic acids [HA] and cations) on PFOA and PFOS removals were also investigated when using the functionalized membrane. PAH/PAA films were first deposited on the membrane using a fluidic layer by layer (LbL) technique and then crosslinked, followed by embedding of the silver …
Emulsion Characterization Study For Improved Bilgewater Treatment And Management, Daniela Diaz Hernandez
Emulsion Characterization Study For Improved Bilgewater Treatment And Management, Daniela Diaz Hernandez
Electronic Theses and Dissertations, 2020-
The need for proper management of bilgewater to meet discharge regulations (e.g., 15 ppm oil) has revealed the necessity to expand the current understanding of bilgewater emulsions. This study proposed to evaluate emulsion stability under various environmental conditions and to identify governing parameters for emulsion formation. The stabilizing properties of eight-commercial cleaners and two-neat surfactants were evaluated. In situ characterization techniques were used for monitoring emulsion stability. Additionally, a needle-type pH microsensor and fluorescence spectroscopy were used for analyzing mass transfer at the oil-water interface. Water quality of extracted bilgewater showed to highly vary between vessels (e.g., conductivity: 1.74 -- …
Improving Air Pollution Exposure Estimation Using Cell Phone Location Data And Low-Cost Sensors, Xiaonan Yu
Improving Air Pollution Exposure Estimation Using Cell Phone Location Data And Low-Cost Sensors, Xiaonan Yu
Electronic Theses and Dissertations, 2020-
Human exposure estimation to air pollution plays an important role in epidemiological studies which are designed to reveal correlations between human exposures to certain air pollutants and certain diseases, such as asthma, cardiovascular disease and reproductive diseases. Traditionally, when people's mobile data is hard to get, home location is used to estimate people's exposures assuming that people stay at home all the time. Whereas, people move and it is more accurate to estimate people's exposures including people's mobility. In our study, we showcased two methods to obtain people's mobile data: Google Maps location history (GMLH) data and Call Detailed Record …
Water Reclamation Using Functionalized Forward Osmosis Membrane, Fnu Joshua
Water Reclamation Using Functionalized Forward Osmosis Membrane, Fnu Joshua
Electronic Theses and Dissertations, 2020-
This study investigated water reclamation from an impaired-quality water using forward osmosis (FO) membrane functionalized by nano zero valent iron (nZVI) loaded polyelectrolyte multilayer films. Stormwater runoff was selected as the impaired-quality water, which served as a feed solution (FS) and a NaCl salt solution at a concentration representing reverse osmosis (RO) concentrate was used a draw solution (DS). RO concentrate is another impaired-quality water that is discharged to the environmental with little or no treatment. A commercial cellulose triacetate (CTA) FO membrane was modified using poly allylamine hydrochloride (PAH) (a polycation) and poly acrylic acid (PAA) (a polyanion) following …
Evaluating The Performance And Impacts Of Seawater Regeneration In An Anion Exchange Process, Daniel Whalen
Evaluating The Performance And Impacts Of Seawater Regeneration In An Anion Exchange Process, Daniel Whalen
Electronic Theses and Dissertations, 2020-
This research investigated the use of seawater regeneration for anion exchange (AIX) processes. Seawater and salt-supplemented seawater regeneration of chloride-form anion resin were evaluated in regard to (1) operational performance efficiency of sulfate and natural organic matter removal, (2) competing exchange of bromide during regeneration, and (3) brominated disinfection by-product (DBP) formation due to bromide leakage. The first component involved bench-scale research that revealed that seawater-based regeneration led to bromide leakage that could be mitigated to an average of 1.82 mg/L using 1% salt-supplemented seawater, and 1.25 mg/L using 3% salt-supplemented seawater. Conceptual cost comparisons revealed that the use of …
Ultraviolet Irradiation Combined With Chlorine Dioxide Pre-Oxidation For Disinfection By-Product Control, Paula Campesino
Ultraviolet Irradiation Combined With Chlorine Dioxide Pre-Oxidation For Disinfection By-Product Control, Paula Campesino
Electronic Theses and Dissertations, 2020-
The use of ultraviolet (UV) light and chlorine dioxide (ClO2) as an advanced oxidation process (AOP) has been investigated at the bench-scale to understand the effects of their use on disinfection by-product (DBP) formation potential (FP) in chlorinated groundwater (GW) and surface water (SW) supplies. Two GWs and two SWs of varying qualities were subject to a series of AOP treatment sequences at the bench scale: sodium hypochlorite, to serve as a baseline; ClO2-Cl2, UV-Cl2, and UV-ClO2-Cl2. In these treatment sequences, Cl2 is used as a primary and secondary disinfectant. Several water quality parameters were measured throughout the experiments, including …
Chemically Stabilized Oil-In-Water Emulsion Separation Using A Custom Aquaporin-Based Polyethersulfone (Pes) Forward Osmosis Membrane System, Annmarie Ricchino
Chemically Stabilized Oil-In-Water Emulsion Separation Using A Custom Aquaporin-Based Polyethersulfone (Pes) Forward Osmosis Membrane System, Annmarie Ricchino
Electronic Theses and Dissertations, 2020-
The stability of oil-in-water emulsions is enhanced by the presence of surfactants in the water, thereby increasing difficulty of remediation. In this study, mineral oil and a standard bilge mix (SBM) were used as model oils for forward osmosis (FO) performance evaluation and two different high-concentration feed solutions (FS) were tested: 10,000 and 100,000 ppm oil/surfactant (9:1 Oil/Surfactant, wt %). It was hypothesized that the charge-charge interactions between the surfactant portion of the micelles and the membrane would play an important role in membrane fouling. Therefore, the effects of both an anionic surfactant (sodium dodecyl sulfate [SDS]) and a nonionic …
Removal Of Chemicals Of Emerging Concern And Mass Transfer Modeling In A Nanofiltration Membrane Process, Carlyn Higgins
Removal Of Chemicals Of Emerging Concern And Mass Transfer Modeling In A Nanofiltration Membrane Process, Carlyn Higgins
Electronic Theses and Dissertations, 2020-
An investigation of 1,4-dioxane and enantiomeric ibuprofen mass transfer in a nanofiltration (NF) membrane process has been completed. Pilot-scale experiments using a 267 gallon per minute (gpm) split-feed, center-port NF process treating pH 6.5 groundwater revealed a consistent 12 percent removal of 1,4-dioxane despite the variable feed concentration (180 nanograms per liter (ng/L) to 38,400 ng/L) when the water flux and temperature were held constant. Bench-scale, flat-sheet NF membrane experiments treating pH 4.0 synthetic water displayed a 34.5 to 49.5 percent removal of racemic ibuprofen. Removal values were dependent on feedwater concentration (1 to 1,500 microgram per liter (µg/L)), pH, …
Removal Of Heavy Metals From Landfill Leachate Using Electrospun Polyelectrolyte Complex Fiber-Laminated Ultrafiltration Membrane, Amirsalar Rabbani Esfahani
Removal Of Heavy Metals From Landfill Leachate Using Electrospun Polyelectrolyte Complex Fiber-Laminated Ultrafiltration Membrane, Amirsalar Rabbani Esfahani
Electronic Theses and Dissertations, 2020-
Ultrafiltration (UF) is a low-pressure membrane process that yields higher permeate flux and saves significant operating costs compared to NF/RO. However, UF has not been applied as a primary method for landfill leachate treatment due to its large pore size. This research investigated the removal of heavy metals from landfill leachate using an UF membrane laminated with fiber mats produced from electrospinning of a polyelectrolyte complex. In this research, we modified the surface of the UF membrane with two polyelectrolytes including Polyacrylic Acid (PAA) and Polyallylamine Hydrochloride (PAH). The removal of heavy metals including Pb, Cd, and Cu from water …