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Full-Text Articles in American Studies

Catalytic Hydrodehalogenation And Hydrogenation Of Halogenated Aromatic Organic Contaminants For Application To Soil Remediation, Claire J. Osborn Jan 2011

Catalytic Hydrodehalogenation And Hydrogenation Of Halogenated Aromatic Organic Contaminants For Application To Soil Remediation, Claire J. Osborn

USF Tampa Graduate Theses and Dissertations

The objective of this research was to aid in the development of a new method for removing and destroying soil contaminants. In particular, 1,2,4,5-tetrachlorobenzene (TeCB) was selected for this research. Hydrodehalogenation (HDH) was paired with hydrogenation for remedially destroying TeCB without generating a secondary waste stream in a single batch reactor. Palladium- and rhodium-catalyzed HDH and hydrogenation were applied in a batch reactor at room temperature and moderate hydrogen pressure. Cyclohexane was formed as an end product with benzene as an intermediate reactant.

An analytical method was developed to measure TeCB, benzene, and cyclohexane in a solution of water and …


Minimal And Symmetric Global Partition Polynomials For Reproducing Kernel Elements, Mario Jesus Juha Jan 2011

Minimal And Symmetric Global Partition Polynomials For Reproducing Kernel Elements, Mario Jesus Juha

USF Tampa Graduate Theses and Dissertations

The Reproducing Kernel Element Method is a numerical technique that combines finite element and meshless methods to construct shape functions of arbitrary order and continuity, yet retains the Kronecker-δ property. Central to constructing these shape functions is the construction of global partition polynomials on an element. This dissertation shows that asymmetric interpolations may arise due to such things as changes in the local to global node numbering and that may adversely affect the interpolation capability of the method. This issue arises due to the use in previous formulations of incomplete polynomials that are subsequently non-affine invariant. This dissertation lays out …


Advances In Fiber Reinforced Polymer Repair Incorporating Cathodic Protection, Julio Ivan Aguilar Jan 2011

Advances In Fiber Reinforced Polymer Repair Incorporating Cathodic Protection, Julio Ivan Aguilar

USF Tampa Graduate Theses and Dissertations

This dissertation presents findings from two disparate research projects relating to the cathodic protection (CP) of piles supporting bridge elements. The first was a proof of concept study for developing a new hybrid pile repair system incorporating embedded sacrificial zinc anodes within a fiber reinforced polymer (FRP) wrap. The second was to develop and remotely monitor the performance of magnesium anodes protecting steel Hpiles supporting two bridges in Florida.

The hybrid FRP-CP system involved a proof-of-concept laboratory study to refine pressure / vacuum bagging systems for pile repair and to quantify the improvement in the FRP concrete bond. Two different …


Feasibility Of Wastewater Reuse For Fish Production In Small Communities In A Developing World Setting, Joshua James Girard Jan 2011

Feasibility Of Wastewater Reuse For Fish Production In Small Communities In A Developing World Setting, Joshua James Girard

USF Tampa Graduate Theses and Dissertations

Eradicating poverty, malnutrition, and the burden of disease have been included as three of the major issues facing the world. The United Nation member countries, having set forth the Millennium Development Goals, have committed themselves to solving these problems. Two major factors which affect solutions to these problems are increasing water stress and implementing improved sanitation. Integration of tilapia aquaculture and reuse of wastewater has been suggested as a solution which addresses both of these factors. The objective of this study is to examine the feasibility, and explore the benefits and drawbacks, to implementing small community wastewater fed (WWF) aquaculture …


Operational Performance Evaluation Of Four Types Of Exit Ramps On Florida's Freeways, Linjun Lu Jan 2011

Operational Performance Evaluation Of Four Types Of Exit Ramps On Florida's Freeways, Linjun Lu

USF Tampa Graduate Theses and Dissertations

This research focuses primarily on the analysis of exit ramp performance related to safety and operations. The safety analysis focuses on the impacts of different exit ramp types for freeway diverge areas and different factors contributing to the crashes that occur on the exit ramp sections. The operational analysis is based mainly on simulations by TSIS-CORSIM. Different ramp effects and guidance for selecting optimal exit ramp type are concluded. Issues related to ramp sections and crossroad sections are also demonstrated. Minimum ramp length and minimum distance between ramp terminal and downstream or upstream intersections are calculated. The operational analysis was …


Oxygen Diffusion Characterization Of Frp Composites Used In Concrete Repair And Rehabilitation, Chandra K. Khoe Jan 2011

Oxygen Diffusion Characterization Of Frp Composites Used In Concrete Repair And Rehabilitation, Chandra K. Khoe

USF Tampa Graduate Theses and Dissertations

Many independent studies have conclusively demonstrated that fiber reinforced polymers (FRP) slow down chloride-induced corrosion of steel in concrete. The mechanism for this slow down is not well understood but it has been hypothesized that FRP serves as a barrier to the ingress of chloride, moisture, and oxygen that sustain electrochemical corrosion of steel.

This dissertation presents results from an experimental study that determined the oxygen permeation rates of materials used in infrastructure repair. In the study, the oxygen permeation constants for epoxy, carbon and glass fiber laminates, concrete, epoxy-concrete and FRP-concrete systems were determined and a method developed to …


Effectiveness Of In-Line Chlorination Of Gravity Flow Water Supply In Two Rural Communities In Panama, Kevin Orner Jan 2011

Effectiveness Of In-Line Chlorination Of Gravity Flow Water Supply In Two Rural Communities In Panama, Kevin Orner

USF Tampa Graduate Theses and Dissertations

It is well established that water quality is directly linked to health. In-line chlorination is one technology that can be used in the developing world to potentially inactivate pathogens and improve water quality. The purpose of this study was to determine the effectiveness of the Panamanian Ministry of Health's in-line PVC chlorinator under three different operating conditions in a rural water supply system. Free and total chlorine were measured entering the storage tank, leaving the storage tank, and at three households along the transmission line of the water system in the two rural indigenous communities of Calabazal and Quebrada Mina …


Investigation Of The Optimal Dissolved Co2 Concentration And Ph Combination For The Growth Of Nitrifying Bacteria, Raymond Anthony Morris Jan 2011

Investigation Of The Optimal Dissolved Co2 Concentration And Ph Combination For The Growth Of Nitrifying Bacteria, Raymond Anthony Morris

USF Tampa Graduate Theses and Dissertations

Ammonium (NH4+) is a biological nutrient that is transformed in a wastewater treatment plant (WWTP) in a process called activated sludge. This is accomplished in an aerobic environment using microorganisms and inorganic carbon that convert the ammonium to nitrate (NO3-). This process is termed nitrification. Removal of ammonium is necessary due to its oxygen demand and toxicity to the environment.

Nitrification is considered a slow process due to the slow growth rate of the nitrifying bacteria. Ammonia oxidizing bacteria (AOB) first covert the ammonium (NH4+) to nitrite (NO2-) …


An Examination Of The Impacts Of Urbanization On Green Space Access And Water Resources: A Developed And Developing World Perspective, Heather E. Wright Wendel Jan 2011

An Examination Of The Impacts Of Urbanization On Green Space Access And Water Resources: A Developed And Developing World Perspective, Heather E. Wright Wendel

USF Tampa Graduate Theses and Dissertations

This dissertation addresses the impact of urbanization and land use change on the availability and accessibility of two urban amenities that are often inequitably distributed: green space and water features. Diverse methodologies were utilized in order to gain a better understanding of the role of these amenities in improving urban quality of life and integrated water management. Using an interdisciplinary approach, this research provides a unique perspective within both a developed and developing world context by evaluating aspects of urbanization to emphasize more sustainable and integrated approaches to development.

A preliminary analysis highlights potential drivers of green space revitalization in …


Anaerobic Membrane Bioreactor (Anmbr) For Treatment Of Landfill Leachate And Removal Of Micropollutants, Anh Tien Do Jan 2011

Anaerobic Membrane Bioreactor (Anmbr) For Treatment Of Landfill Leachate And Removal Of Micropollutants, Anh Tien Do

USF Tampa Graduate Theses and Dissertations

To date, most studies on the fate and removal of endocrine disrupting compounds (EDCs) and pharmaceutical and personal care products (PPCPs) in wastewater focus on their fate in municipal wastewater treatment plants, and mostly under aerobic condition. There are limited studies related to anaerobic condition and (to our knowledge) no study on the removal of EDCs in landfill leachate by AnMBR. Moreover, for most studies under anaerobic condition, the removal of EDCs was only reported in the liquid phase; solid phase extraction was not reported, thereby preventing mass balance in the studies.

This research was conducted to investigate the potential …


Computational Discovery Of Phenotype Related Biochemical Processes For Engineering, Andrea M. Rocha Jan 2011

Computational Discovery Of Phenotype Related Biochemical Processes For Engineering, Andrea M. Rocha

USF Tampa Graduate Theses and Dissertations

Application of bioengineering technologies for enhanced biological hydrogen production is a promising approach that may play a vital role in sustainable energy. Due to the ability of several naturally occurring microorganisms to generate hydrogen through varying metabolic processes, biological hydrogen has become an attractive alternative energy and fuel source.

One area of particular interest is the production of biological hydrogen in organically-rich engineered systems, such as those associated with waste treatment. Despite the potential for high energy yields, hydrogen yields generated by bacteria in waste systems are often limited due to a focus on microbial utilization of organic material towards …


Modeling Roadside Safety Hazards To Predict Annual Crash Cost To Encroaching Vehicles In Rural Road Networks, Isidro Delgado Jan 2011

Modeling Roadside Safety Hazards To Predict Annual Crash Cost To Encroaching Vehicles In Rural Road Networks, Isidro Delgado

USF Tampa Graduate Theses and Dissertations

Roadside crashes account for a large portion of total fatal crashes that occur annually in the United States. About 30% of those fatalities are the result of single vehicle run-off-road crashes. A large proportion of these fatal crashes occur in rural roads when vehicles depart from the travel lane and collide with trees or other roadside safety hazards. Many of these run-off-road accidents occur in local roads that carry traffic volumes between 1,000 and 20,000 vehicles per day. Many of these roads are part of the jurisdiction of county authorities faced with the dilemma of having too many "potentially dangerous" …


Physically Meaningful Harmonization Of Tire/Pavement Friction Measurement Devices, Madhura Priyanga Nishshanke Rajapakshe Jan 2011

Physically Meaningful Harmonization Of Tire/Pavement Friction Measurement Devices, Madhura Priyanga Nishshanke Rajapakshe

USF Tampa Graduate Theses and Dissertations

Accurate characterization and evaluation of tire/pavement friction is critical in assuring runway and highway safety. Historically, Pavement Friction Measurement Devices (PFMDs) employing different measuring mechanisms have been used to evaluate tire/pavement friction. They yield significantly disparate friction coefficients under the same contact conditions. Currently, an empirically developed data harmonization method based on a reference device (Dynamic Friction Tester (DFT)) is used in an attempt to overcome the disparities between the measurements using various different PFMDs. However, this method, which has been standardized by the American Society for Testing and Materials (ASTM E1960), has been criticized for its inconsistency by researchers …


Mechanistic Modeling Of Photocatalytic Water Disinfection, Omatoyo Kofi Dalrymple Jan 2011

Mechanistic Modeling Of Photocatalytic Water Disinfection, Omatoyo Kofi Dalrymple

USF Tampa Graduate Theses and Dissertations

The main goal of this research was to develop a mechanism-based model for photocatalytic disinfection of bacteria in water using suspended catalyst pthesiss in batch reactors. The photocatalytic disinfection process occurs as a semiconductor photocatalyst, most commonly titanium dioxide (TiO2), is irradiated with light of wavelength less than 380 nm to produce hydroxyl radicals and other highly reactive oxidants which can inactivate microorganisms. Photocatalytic disinfection involves a complex interaction of many fundamental mechanisms such as light absorption and scattering by semiconductor pthesiss, electrochemical surface reactions, and heterogeneous colloidal stability. Current models, based largely on chemical reacting systems, do …


Restoration Of Displaced Cast-In-Place Concrete Slabs On Grade With The Use Of The Isb-07 Subsurface Support Bracket, Jose Carlos Busquets Jan 2011

Restoration Of Displaced Cast-In-Place Concrete Slabs On Grade With The Use Of The Isb-07 Subsurface Support Bracket, Jose Carlos Busquets

USF Tampa Graduate Theses and Dissertations

The restoration of foundations of residential and light commercial structures that have been affected by differential displacement resulting from problematic soil conditions has been an ongoing issue since early times. In Florida, the issue of structures being affected by subsidence of soils related to sinkhole activity has been a problem that has gained more interest and exposure within the last 20 years. Structures affected by sinkholes have been historically addressed by remediating the soil mechanism which caused the structure to displace and then structurally addressing the portions of the structure that have displaced with steel underpins installed on the foundation. …


Thermal Integrity Profiling Instrumentation Development, Byron Keith Anderson Jan 2011

Thermal Integrity Profiling Instrumentation Development, Byron Keith Anderson

USF Tampa Graduate Theses and Dissertations

This thesis has shown that the development of the instrumentation necessary to provide in-situ thermal imaging for the determination of homogeneity of concrete is theoretically sound.

Drilled shafts are large diameter underground cast-in-place columns that necessarily rely on sound integrity to properly withstand imposed loadings. As a by-product of the most common construction techniques, the entire process is often completely blind whereby the excavation and concreting processes are conducted beneath the surface of the water table (or slurry level). This results in an inability to inspect the final product and in many cases allows anomalous inclusions (soil cave-ins, slurry pockets, …


Effects Of Solids Loadings And Particle Size Distribution On Siphon Ceramic Candle Filters, Danielle Renzi Jan 2011

Effects Of Solids Loadings And Particle Size Distribution On Siphon Ceramic Candle Filters, Danielle Renzi

USF Tampa Graduate Theses and Dissertations

In the rural areas of Madagascar only 29% of the population has access to clean water and 10% has access to improved sanitation. It has been estimated that environmental risk factors, such as inadequate access to clean drinking water and proper sanitation, are responsible for 94% of the diarrheal disease burden. This study was focused on testing a point-of-use technology called the Tulip filter, which is a siphon ceramic candle filter impregnated with silver. The purpose is to assess its feasibility for implementation in rural regions of Madagascar through a laboratory study performed at the University of South Florida.

The …


Pilot Assessment Of Novel Membrane Bioreactor Processes - Improvements In Biological Nutrient Removal And Membrane Operation, Shaleena Smith Jan 2011

Pilot Assessment Of Novel Membrane Bioreactor Processes - Improvements In Biological Nutrient Removal And Membrane Operation, Shaleena Smith

USF Tampa Graduate Theses and Dissertations

With increasing water reuse applications and upcoming stringent regulations for treated wastewater effluent discharge, wastewater plants need to consider alternative technologies beyond conventional treatment processes. The new regulations, Numeric Nutrient Criteria (NNC), may regulate discharge nitrogen and phosphorus concentrations to as low as 0.5 mg/L as N and 10 μg/L as P respectively. To meet these target requirements, system retrofitting to incorporate chemical or advanced nutrient removal systems possibly with membrane technology will most likely be required. Although microfiltration/ultrafiltration membranes coupled with biological processes, otherwise known as membrane bioreactors (MBR), remove contaminants and suspended solids, nutrient removal is minimal to …