Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Actinide (2)
- Adsorption (2)
- 1 (1)
- 2-butoxyethanol (1)
- 2-propanediol (1)
-
- Activated Carbon (1)
- Aerobic biodegradation (1)
- Aliphatic Synthetic Organic Compounds (1)
- Amines (1)
- Anaerobic biodegradation (1)
- Biomass accumulation (1)
- Bioretention (1)
- Brewer fermentation waste (1)
- CO2 storage (1)
- Carbon Nanotube (1)
- Carbon Nanotubes (1)
- Carbon sequestration (1)
- Chloramines (1)
- Chlorella protothecoides (1)
- Corexit (1)
- Crude glycerol (1)
- Dendritic polymer (1)
- Detection (1)
- Disinfection By-Products (1)
- Drinking Water Treatment (1)
- Effectiveness (1)
- Flow-Cell (1)
- Geochemistry (1)
- Geographic Information Systems (GIS) (1)
- Graphene (1)
- Publication
Articles 1 - 19 of 19
Full-Text Articles in Entire DC Network
Toward Understanding The Thermodynamics And Mechanisms Of Actinide Sorption Reactions, Shanna Estes
Toward Understanding The Thermodynamics And Mechanisms Of Actinide Sorption Reactions, Shanna Estes
All Dissertations
The environmental fate of actinides is greatly influenced by interfacial reactions, including sorption onto solid surfaces. Because changes in the primary hydration sphere of the actinide are expected to greatly influence the thermodynamics (i.e., reaction enthalpy and entropy) of these reactions, examining actinide sorption thermodynamics may provide insight into actinide sorption mechanisms. Additionally, examining actinide sorption thermodynamics may enhance the ability to model or predict these reactions in environmental or engineered systems where variable or elevated temperatures are expected. However, few researchers have studied actinide sorption thermodynamics. Therefore, this research examined the thermodynamics of Eu(III) (a trivalent actinide analog), Th(IV), …
The Effects Of Secondary Trapping Mechanisms On Geologic Storage Of Carbon Dioxide, Catherine Ruprecht
The Effects Of Secondary Trapping Mechanisms On Geologic Storage Of Carbon Dioxide, Catherine Ruprecht
All Dissertations
The goal of this Dissertation is to further the understanding of secondary trapping mechanisms in geologic CO2 storage systems to improve storage design and security. This Dissertation takes the form of three chapters. The objective of the first chapter was to analyze the storage performance of supercritical and brine saturated CO2 injection strategies to determine their advantages and disadvantages on distribution and immobilization of CO2 and pressure buildup. Results showed dissolved CO2 injection was favorable in terms of storage security in all cases as it resulted in smaller areal extents on the caprock and did not …
Experimental Evidence For Colloid-Facilitated Transport Of Plutonium, Hilary Emerson
Experimental Evidence For Colloid-Facilitated Transport Of Plutonium, Hilary Emerson
All Dissertations
Colloid-facilitated transport of the actinides has been observed previously in the field on the kilometer scale. The objective of this work is to investigate the mechanisms of colloid-facilitated transport with controlled settings and conditions. The experimental work in this dissertation investigates transport of a ternary complex with iron oxide colloids, organic ligands and actinides in the presence of quartz or a natural sandy soil as well as simplified systems building up to the ternary complexes. The first three papers investigate the following: (1) unsaturated transport of iron oxide colloids in a natural sandy soil lysimeter with and without natural organic …
Fast Fission Neutron Detection Using The Cherenkov Effect, Matthew Millard
Fast Fission Neutron Detection Using The Cherenkov Effect, Matthew Millard
All Theses
The Cherenkov effect in optically clear media of varying indices of refraction and composition was investigated for quantification of fast neutrons. The ultimate application of the proposed detection system is criticality monitoring. The optically clear medium, composed of select target nuclei, was coupled to a photomultiplier tube. Neutron reaction products of the target nuclei contained within the optical medium emit beta particles and gamma rays that produce Cherenkov photons within the medium which can be detected. Assessed media include quartz (SiO2), sapphire (Al2O3), spinel (MgAl2O4), and zinc sulfide (ZnS), which were irradiated with un-moderated 252Cf. Monte Carlo N-Particle (MCNP) code …
Optimizing Light Collection From Extractive Scintillating Resin In Flow-Cell Detectors, Amy Meldrum
Optimizing Light Collection From Extractive Scintillating Resin In Flow-Cell Detectors, Amy Meldrum
All Theses
The objectives of this study were to investigate the changes in light collection efficiency for flow cell detector as various parameters are altered to find the optimum flow cell configuration. Columns with inner diameters of 0.16 cm, 0.48 cm, 0.79 cm, and 1.11 cm were packed with synthesized nonporous, un-functionalized beads to measure their detection efficiencies for solutions containing 210Po, 14C, or 90Sr/90Y. The average diameter of the beads used in the experiments was 147 µm ± 33 µm. The highest detection efficiency for 210Po was 15.3 ± 3.9% with the 1.11 cm diameter column. The 1.11 cm diameter column …
Using Gis To Prioritize Green Infrastructure Installation Strategies In An Urban Watershed, Lauren Owen
Using Gis To Prioritize Green Infrastructure Installation Strategies In An Urban Watershed, Lauren Owen
All Theses
This study seeks to quantify runoff volume generation and peak flow rates from the urban Sand River Headwaters to determine the most effective placement of additional green infrastructure in Aiken, SC. ArcMap 10.1, HEC-GeoHMS, and HEC-HMS were used to delineate a total outlet watershed along with subwatershed(s) for urban stormwater infrastructure system by 'burning' the stormwater system at an artificial elevation below the existing topologically-based Digital Elevation Model (DEM). The result was a higher resolution DEM that allowed for storm routing and subsequent volume and flow predictions compared to that based on the original DEM created by using Light Detecting …
The Effects Of Amine Structure, Chloramine Species And Oxidation Strategies On The Formation Of N-Nitrosodimethylamine, Meric Selbes
The Effects Of Amine Structure, Chloramine Species And Oxidation Strategies On The Formation Of N-Nitrosodimethylamine, Meric Selbes
All Dissertations
To comply with the increasingly stringent disinfection by-product (DBP) regulations in the United States, many water treatment plants have been switching from chlorination to chloramination in the last decade. Although chloramination reduces the formation of regulated DBPs such as trihalomethanes and haloacetic acids, it causes the formation of nitrosamines. Nitrosamines are a class of compounds that are probable human carcinogens, mutagens and teratogens at concentrations as low as 0.2 ng/L. In particular, N-nitrosodimethylamine (NDMA) is the most frequently detected nitrosamine in distribution systems in the United States. Although, nitrosamines are currently not regulated by the USEPA, they have been recently …
Effects Of Natural Organic Matter On Contaminant Removal By Superfine Powdered Activated Carbon Coupled With Microfiltration Membranes, Mengfei Li
All Theses
Hybrid activated carbon/membrane systems are used in drinking water treatment for their significant capability of removing synthetic organic contaminants (SOCs) or taste-and-odor compounds along with particles. Preliminary data showed that decreasing the carbon particle size and creating superfine powdered activated carbon (S-PAC) removed phenanthrene and atrazine better than adsorbents with larger particle size in the presence of competitive adsorbents like natural organic matter (NOM). NOM is present in all natural water from degradation of terrestrial biomass which leaches from soil into a water source. Water treatment facilities target the removal of NOM because they are precursors to disinfection by-products formed …
Potential Effects Of Geologic Storage Of Co2 On Surface Water And Shallow Groundwater, Shuangshuang Xie
Potential Effects Of Geologic Storage Of Co2 On Surface Water And Shallow Groundwater, Shuangshuang Xie
All Theses
ABSTRACT Storage of supercritical phase CO2 in deep saline aquifers is being considered to reduce greenhouse gases in the atmosphere, and this process is expected to increase the pressure in these deep aquifers. One potential consequence of pressurization is an increase in the upward flux of saline water. Saline groundwater occurs naturally at shallow depths in many sedimentary basins, so an upward flux of solutes could degrade the quality of aquifers, and threaten aquatic ecosystems where groundwater discharge is important. The objective of this research is to evaluate the impacts associated with increasing the upward flux of saline water as …
The Use Of Oxidants For Ndma Precursor Deactivation In Wastewater Treatment, Jaclyn Lauer
The Use Of Oxidants For Ndma Precursor Deactivation In Wastewater Treatment, Jaclyn Lauer
All Theses
Water treatment plants in the United States (US) have been switching from chlorination to chloramination in the search for a disinfection process to reduce formation of regulated disinfection by-products (DBPs). Unfortunately, the trade-off is the formation of N-nitrosamines. N-nitrosodimethylamine (NDMA) is the most commonly detected N-nitrosamine in US distribution systems. In the Integrated Risk Information Service (IRIS) database of the United States Environmental Protection Agency (USEPA), NDMA has been identified to have an estimated 10-6 lifetime cancer risk level at a concentration of 0.7 ng/L in drinking water. N-nitrosamines are currently not regulated by the USEPA; however, are listed on …
Anaerobic And Aerobic Biodegradation Of The Oil Dispersant Components 1,2-Propanediol And 2-Butoxyethanol In Seawater, Benjamin Rhiner
Anaerobic And Aerobic Biodegradation Of The Oil Dispersant Components 1,2-Propanediol And 2-Butoxyethanol In Seawater, Benjamin Rhiner
All Theses
Oil spills are a recurring issue associated with fossil fuel consumption. The largest accidental oil spill in the history of the petroleum industry was the Deepwater Horizon explosion and seafloor well blowout, where the Deepwater Horizon oil rig exploded and sank, allowing the well to gush uncontrolled from April 20, 2010, until it was capped on July 15, 2010, releasing an estimated 210,000,000 gallons of oil. Oil dispersants were used in unprecedented quantities during the cleanup response to the spill with a total of 1,840,000 gallons of the dispersant COREXIT being applied. The goal of this research was to evaluate …
Predictive Model Development For Adsorption Of Organic Contaminants By Carbon Nanotubes, Onur Apul
Predictive Model Development For Adsorption Of Organic Contaminants By Carbon Nanotubes, Onur Apul
All Dissertations
The main objective of the study was to investigate mechanisms and statistical modeling of synthetic organic contaminant (SOC) adsorption by carbon nanotubes (CNTs). First, predictive models were developed for adsorption of low molecular weight aromatic compounds by multi-walled carbon nanotubes (MWCNTs) using experimental data for 59 compounds. Quantitative structure-activity relationship (QSAR) and linear solvation energy relationship (LSER) approaches were employed and developed models were externally validated using an independent dataset obtained from the literature. Up to date, no QSAR model has been reported for predicting adsorption of organics by CNTs. No LSER model is available which comprehensively investigates the adsorption …
An Examination Of Radionuclide Transport In The Vadose Zone Using Field Lysimeters, Michael Witmer
An Examination Of Radionuclide Transport In The Vadose Zone Using Field Lysimeters, Michael Witmer
All Theses
Understanding how radionuclides interact in the subsurface is important for the remediation of contaminated sites, assessment of risk due to radioactive waste disposal, and designing new radioactive waste management strategies. The current understanding of the geochemical behavior of radionuclides in the subsurface and more specifically the vadose zone has been developed through reactive transport modeling supplemented by laboratory experiments. Interactions between radionuclides with the mineral particles and organic matter in the vadose zone can be very complex and while laboratory experiments produce valuable data, few controlled, intermediate scale transport studies have been performed. In order to accurately predict vadose zone …
Adsorption Of Halogenated Aliphatic Contaminants By Graphene Nanomaterials: Comparison With Carbon Nanotubes And Granular Activated Carbons, Yang Zhou
All Theses
Graphene nanomaterials are two-dimensional single layer sp2 hybridized carbon atoms densely packed in a hexagonal honeycomb lattice and can be visualized as basic building blocks for fullerenes, carbon nanotubes (CNTs), and graphite. In addition, they are hydrophobic nanomaterials and possess a large specific surface area (SSA), thus they have been evaluated as promising adsorbents to remove synthetic organic compounds (SOCs) from water. As with granular activated carbons (GACs) and CNTs, adsorption behavior of SOCs on graphene depends on the physicochemical properties of the adsorbents (e.g., specific surface area, pore size distribution and surface chemistry), SOCs (e.g., hydrophobicity, molecular size and …
Dendritic Polymers As Biocompatible Oil Spill Dispersants: Effectiveness And Mechanisims With Crude Oil, Ying Tu
All Theses
Dendritic polymers have recently been shown to entrap polycyclic aromatic hydrocarbons (PAHs) and other hydrophobic materials. Laboratory results have shown that poly(amidoamine) dendrimers and hyperbranched poly(ethyleneimine) polymers form complexes with linear (hexadecane) and polyaromatic (phenanthrene) hydrocarbons, increasing the dispersion of these model crude oil components. It is thus hypothesized that crude oil can be dispersed using these polymers. Compared with commercial dispersants, dendritic polymers have the potential to be more biocompatible and less toxic. The objective of this research was to gain a fundamental understanding of the interactions of dendritic polymers with crude oil. We used Louisians Sweet Crude oil …
Ecohydrological Function Of Lower Coastal Plain Bioretention Cells In South Carolina, Jessica Palazzolo
Ecohydrological Function Of Lower Coastal Plain Bioretention Cells In South Carolina, Jessica Palazzolo
All Theses
Flooding and stormwater control is a critical issue in coastal South Carolina because of shallow water table elevation, topography and rapid urbanization in the region. A best management practice (BMP) using low impact design (LID) principles known as a bioretention cell (BRC) is gaining popularity for stormwater management. Five BRCs in four landscape positions (well-drained uplands, tidal-proximal, poorly-drained-uplands, and floodplain) were instrumented for microclimate, soil moisture, and water table elevation for hydraulic efficiency and for water quality measurements. Three BRCs did not have an overflow outlets, one BRC (floodplain) employed an underdrain system, and one BRC (tidal proximal) had an …
Biomass And Lipid Production Of Chlorella Protothecoides Under Heterotrophic Cultivation On A Mixed Waste Substrate Of Brewer Fermentation And Crude Glycerol, Xiaoyu Feng
All Theses
Biodiesel production using Chlorella protothecoides microalgae species has become an attractive topic due to the intense requirements of renewable energy in past decades. While, the expensive capital cost of the carbon and nitrogen substrates for algae growth is becoming a restrictive problem in this filed. In this study, heterotrophic cultivation of Chlorella protothecoides in the dark was conducted in 500mL shake flasks. Chlorella protothecoides growth in mixed substrate of brewer fermentation and biodiesel crude glycerol by-products containing a relatively high concentration of carbon and nitrogen was discussed and compared with that in microalgae basal medium which was supplied with 30 …
Density Functional Theory Study Of The Thermodynamics Of Catalytic Remediation Of Nitrate In Water, Lizzie Bollmann
Density Functional Theory Study Of The Thermodynamics Of Catalytic Remediation Of Nitrate In Water, Lizzie Bollmann
All Theses
Over 1 billion people worldwide lack access to safe drinking water and 5,000 people die each day due to drinking contaminated water. With the development of new industries, new substances and chemicals are entering the waters every day, and the current water treatment processes are unable to remove them entirely. For example, agriculture is the world's heaviest consumer of water, and nitrates and nitrites from fertilizers are washed away with the water to rivers and streams. These chemicals can cause problems to humans and to the environment. To humans, they can cause methemoglobinemia, also known as 'blue baby syndrome'. To …
Adsorption Of Synthetic Organic Chemicals: A Comparison Of Superfine Powdered Activated Carbon With Powdered Activated Carbon, Semra Bakkaloglu
Adsorption Of Synthetic Organic Chemicals: A Comparison Of Superfine Powdered Activated Carbon With Powdered Activated Carbon, Semra Bakkaloglu
All Theses
In literature, manufacturer-supplied powdered activated carbon has been ground to produce submicron particles with mean diameter lower than 1µm for use as an adsorbent during water treatment. Superfine powdered activated carbon (SPAC) can be used for removal of natural organic matter as well as synthetic organic chemicals (SOCs) from water. It has been suggested that SPAC has higher adsorption capacity than powdered activated carbon (PAC) due to larger external surface area and mesopore volume. Another advantage of SPAC over PAC is the faster uptake rate for both NOM and SOC during adsorption owing to small particle size. Therefore, understanding SPAC …