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In Situ Biofiltration Of Dissolved Organic Carbon In Reverse Osmosis Membrane Filtration, Russell Rosario Ferlita Jan 2011

In Situ Biofiltration Of Dissolved Organic Carbon In Reverse Osmosis Membrane Filtration, Russell Rosario Ferlita

USF Tampa Graduate Theses and Dissertations

Biofouling, or the formation of biofilm on membrane surfaces, can decrease the performance (decreased flux and/or increased operating pressure) of a reverse osmosis (RO) membrane system in a water treatment plant. However, biofilms have been used in water treatment systems to remove organic carbon from water via biofilters and successfully reduce biofilm growth downstream. This research investigates the possibility that the heterotrophic biofilm present on membrane surfaces removes nutrients from the treatment water, thereby making it nutrient deprived as it travels along the treatment train. This may potentially be exploited as an in situ biofilter to actively remove dissolved organic …


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 …


Guiding Electric Fields For Electroporation Applications, Jose Rey Jan 2011

Guiding Electric Fields For Electroporation Applications, Jose Rey

USF Tampa Graduate Theses and Dissertations

Electroporation is the critical step in an electric field mediated drug or gene delivery protocol. Electroporation based protocols have been successfully demonstrated in cancer clinical trials, however, its impact in other applications is still under investigation. A significant roadblock to long term functioning of implantable biosensors in vivo is the tissue reaction in the form of fibrous encapsulation that results in reduced transport to the sensing element of the biosensor. In vivo gene electroporation has a great potential as a means to modify the transport properties of tissues in the proximity of the sensing element of implantable biosensors.

This dissertation …


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 …


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 …


Design Of Small Scale Anaerobic Digesters For Application In Rural Developing Countries, Laurel Erika Rowse Jan 2011

Design Of Small Scale Anaerobic Digesters For Application In Rural Developing Countries, Laurel Erika Rowse

USF Tampa Graduate Theses and Dissertations

The high incidence of upper respiratory diseases, contamination of waterways due to pathogens and nutrients from human and animal wastes, unsustainable deforestation, gender disparities in burden of disease due to unequal exposure to indoor air pollutants, and carbon black emissions from the burning of solid fuels are interrelated problems in many developing countries. Small scale anaerobic digestion provides a means of alleviating these problems by treating livestock waste onsite to produce biogas (methane and carbon dioxide) in rural areas in developing countries. Fuel can then be used for cooking, lighting, and heating. Methane fuel is an alternative to traditional three-stone …


Modeling And Parameter Study Of Bistable Spherical Compliant Mechanisms, Chester Smith Jan 2011

Modeling And Parameter Study Of Bistable Spherical Compliant Mechanisms, Chester Smith

USF Tampa Graduate Theses and Dissertations

The bistable spherical compliant mechanism (BSCM) is a novel device capable of large, repeatable, out-of-plane motion, characteristics that are somewhat difficult to achieve with surface micromachined microelectromechanical systems. An improved pseudo-rigid-body model (PRBM) to predict the behavior of the BSCM is presented. The new model was used to analyze seven different versions of the device, each with a different compliant joint length. The new model, which adds torsion, is compared with a finite element analysis (FEA) beam model. The new model more closely approximates the results yielded by FEA than previous models used to analyze the BSCM. Future work is …


A Novel Device For Cell-Cell Electrofusion, Justin T. Stewart Jan 2011

A Novel Device For Cell-Cell Electrofusion, Justin T. Stewart

USF Tampa Graduate Theses and Dissertations

Cell transplantation therapy is a potentially powerful tool and can be used to replace defective cells with healthy cells. This offers the possibility of alleviating the destructive symptoms for many diseases such as Parkinson's disease, Alzheimer's disease, stroke, spinal cord trauma, Type I diabetes and many more. While there are many diseases that could be positively impacted from cell transplantation therapy, the focus of this research is insulin dependent, Type I Diabetes.

The Islets of Langerhans are composed of various types of cells located in the pancreas and are responsible for a variety of biochemical functions. Specifically, the beta Islet …


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 …


Growth And Characterization Of Thermoelectric Ba8Ga16Ge30 Type-I Clathrate Thin-Films Deposited By Pulsed Dual-Laser Ablation, Robert Harry Hyde Jan 2011

Growth And Characterization Of Thermoelectric Ba8Ga16Ge30 Type-I Clathrate Thin-Films Deposited By Pulsed Dual-Laser Ablation, Robert Harry Hyde

USF Tampa Graduate Theses and Dissertations

The on-going interest in thermoelectric (TE) materials, in the form of bulk and films, motivates investigation of materials that exhibit low thermal conductivity and good electrical conductivity. Such materials are phonon-glass electron-crystals (PGEC), and the multi-component type-I clathrate Ba8Ga16Ge30 is in this category. This work reports the first investigation of Ba8Ga16Ge30 films grown by pulsed laser deposition (PLD).

This dissertation details the in-situ growth of polycrystalline type-I clathrate Ba8Ga16Ge30 thin-films by pulsed laser ablation. Films deposited using conventional laser ablation produced films that contained a …


A Remotely Operated Multi-Tracked Vehicle For Subterranean Exploration Of Gopher Tortoise Burrows, William Keese Jan 2011

A Remotely Operated Multi-Tracked Vehicle For Subterranean Exploration Of Gopher Tortoise Burrows, William Keese

USF Tampa Graduate Theses and Dissertations

The gopher tortoise is a land tortoise living in the southeastern United States. It is a species in decline and is listed as threatened or endangered in six different states. The gopher (as commonly referred) digs burrows that it uses for many reasons and spends most of its time underground. Problems occur when trying to estimate a population because a gopher tortoise digs more than one burrow. This thesis demonstrates an innovative way to survey and investigate a gopher tortoise burrow hole by using a multi-tracked remotely operated vehicle. The vehicle carried two cameras (fore and aft) and was equipped …


Biodegradation Of Bisphenol-A And 17b-Estradiol In Soil Mesocosms Under Alternating Aerobic/Anoxic/Anaerobic Conditions, Won-Seok Kim Jan 2011

Biodegradation Of Bisphenol-A And 17b-Estradiol In Soil Mesocosms Under Alternating Aerobic/Anoxic/Anaerobic Conditions, Won-Seok Kim

USF Tampa Graduate Theses and Dissertations

Soil-aquifer treatment (SAT) has been proposed as a method for reusing treated municipal wastewater. SAT is characterized by alternating cycles of aerobic and anaerobic conditions in the subsurface, in response to alternating cycles of flooding and drainage of a surface impoundment. It is not yet known how these alternating redox conditions affect the removal of potentially harmful endocrine-disrupting compounds (EDCs) from treated effluent.

The overall objective of my doctoral research is to determine the fate of EDCs in alternating aerobic/anoxic/anaerobic conditions under simulated SAT conditions. To assess the fate of EDCs in simulated SAT conditions, I first had to develop …


A Swmm-5 Model Of A Denitrifying Bioretention System To Estimate Nitrogen Removal From Stormwater Runoff, Michelle D. Masi Jan 2011

A Swmm-5 Model Of A Denitrifying Bioretention System To Estimate Nitrogen Removal From Stormwater Runoff, Michelle D. Masi

USF Tampa Graduate Theses and Dissertations

This research estimates nitrogen removal from stormwater runoff using a denitrifying bioretention system using the USEPA Storm Water Management Model Version 5 (SWMM-5). SWMM-5 has been used to help planners make better decisions since its development in 1971. A conventional bioretention system is a type of Low Impact Development (LID) technology, which designed without a media layer specifically for achieving nitrogen removal. More recently studies have showed that high TN removal efficiencies are possible when incorporating a denitrification media layer. These systems are known as denitrifying bioretention systems, or alternative bioretention systems. LID projects are currently being designed and developed …


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-) …


Environmental Health In The Latin American And Caribbean Region: Use Of Water Storage Containers, Water Quality, And Community Perception, Erlande Omisca Jan 2011

Environmental Health In The Latin American And Caribbean Region: Use Of Water Storage Containers, Water Quality, And Community Perception, Erlande Omisca

USF Tampa Graduate Theses and Dissertations

Water quality and availability are important issues in many developing countries where portions of populations still lack access to potable water. Throughout the English-speaking Caribbean and parts of Latin America, households and businesses invest in water supply systems even when they are connected to and pay for water services from a private or state owned provider. Inconsistent supplies of water from the water companies have led many people to invest in storage tanks which, if operated correctly, can provide water throughout the day even when the supply from the main is low or zero. While these individual systems help to …


Surface Functionalization And Analysis Thereof For An Ovarian Cancer Diagnostic Biosensor, Asad Ali Ahmad Jan 2011

Surface Functionalization And Analysis Thereof For An Ovarian Cancer Diagnostic Biosensor, Asad Ali Ahmad

USF Tampa Graduate Theses and Dissertations

Ovarian cancer is the fifth leading cause of cancer death among women in United States and has an alarming 1.4% (1 in 71) lifetime risk. The lack of overt symptoms and the absence of a reliable screening test to detect ovarian cancer result in over 70% of women being diagnosed after the disease has spread beyond the ovary resulting in a poor prognosis. A key characteristic of ovarian cancer is the ability of tumor cells to evade apoptosis, or programmed cell death contributing to the limitless replicative potential, which is a hallmark of all carcinogenesis. There is conclusive evidence that …


Thermal Response Of Lithium Tantalate For Temperature Measurement, Ardit Agastra Jan 2011

Thermal Response Of Lithium Tantalate For Temperature Measurement, Ardit Agastra

USF Tampa Graduate Theses and Dissertations

This thesis describes the study of the thermal response of the pyroelectric material named lithium tantalate or LT (LiTaO3) in aid of this material’s possible use for temperature measurement. The temperature range studied was between 5-99 oC. The sensor was excited using a silicon rubber heater. The lithium tantalate sensor and the rubber heater were enclosed such that the temperature would reach steady state faster. The enclosure was a small insulated box in order to reduce any extraneous effects on the sensor. The output signal of the lithium tantalate sensor was then amplified by using four different amplifying circuits and …


Novel Magnetic Materials For Sensing And Cooling Applications, Anurag Chaturvedi Jan 2011

Novel Magnetic Materials For Sensing And Cooling Applications, Anurag Chaturvedi

USF Tampa Graduate Theses and Dissertations

The overall goals of the present PhD research are to explore the giant magnetoimpedance (GMI) and giant magnetocaloric (GMC) effects in functional magnetic materials and provide guidance on the optimization of the material properties for use in advanced magnetic sensor and refrigeration applications.

GMI has attracted growing interest due to its promising applications in high-performance magnetic sensors. Research in this field is focused on the development of new materials with properties appropriate for practical GMI sensor applications. In this project, we have successfully set up a new magneto-impedance measurement system in the Functional Materials Laboratory at USF. We have established, …


Supercritical Fluid Aided Microencapsulation Of Dry Powders, Raquel Carvallo Jan 2011

Supercritical Fluid Aided Microencapsulation Of Dry Powders, Raquel Carvallo

USF Tampa Graduate Theses and Dissertations

Coating of fine particles to produce tailored surface properties is currently a key development for supercritical fluids applications, in different areas such as: pharmaceutical, nutraceutical, cosmetic, agrochemical, electronic and specialty chemistry industries. During the encapsulation process the particles surface can be designed with specific properties by spreading a thin film coating material over the surface of the particles.

Chitosan, a natural polymer, was used in this work as the encapsulant material. Chitosan is biocompatible, biodegradable to normal body constituents, safe, non-toxic, bacteriostatic, anticancerogen, and versatile polymer. These attributes are among the properties that make Chitosan an attractive component of pharmaceutical …


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 …


Apparent Total Evaporative Resistance Values From Human Trials Over A Range Of Metabolic And Heat Stress Levels, Matthew David Dooris Jan 2011

Apparent Total Evaporative Resistance Values From Human Trials Over A Range Of Metabolic And Heat Stress Levels, Matthew David Dooris

USF Tampa Graduate Theses and Dissertations

Failure to maintain thermal equilibrium can cause uncontrollable increases in body core temperature beyond critical upper limits. In selecting clothing, consideration must be given to the heat transfer properties of clothing that may restrict the cooling capacity of the human body under heat stress conditions, most importantly, apparent total evaporative resistance (Re,T,a). This study calculated and compared Re,T,a for five clothing ensembles under varying heat stress conditions, including three relative humidity (RH) levels and three stages of heat stress to determine if Re,T,a values varied or remained the same with …


Measurement And Characterization Of Terahertz Radiation Propagating Through A Parallel Plate Waveguide, Matthew George Wachsmuth Jan 2011

Measurement And Characterization Of Terahertz Radiation Propagating Through A Parallel Plate Waveguide, Matthew George Wachsmuth

Dissertations and Theses

As the amount of study into the terahertz (THz) region of the electromagnetic spectrum steadily increases, the parallel plate waveguide has emerged as a simple and effective fixture to perform many experiments. The ability to concentrate THz radiation into a small area or volume enables us to analyze smaller samples and perform more repeatable measurements, which is essential for future research. While the fundamental physics of PPW transmission are understood mathematically, the practical knowledge of building such a fixture for the THz domain and taking measurements on it with a real system needs to be built up through experience. In …


A Framework For Determining The Reliability Of Nanoscale Metallic Oxide Semiconductor (Mos) Devices, Wilkistar Otieno Dec 2010

A Framework For Determining The Reliability Of Nanoscale Metallic Oxide Semiconductor (Mos) Devices, Wilkistar Otieno

USF Tampa Graduate Theses and Dissertations

An increase in worldwide investments during the past several decades has pro-pelled scienti c breakthroughs in nanoscience and technology research to new and exciting levels. To ensure that these discoveries lead to commercially viable prod-ucts, it is important to address some of the fundamental engineering and scientific challenges related to nanodevices. Due to the centrality of reliability to product integrity, nanoreliability requires critical analysis and understanding to ensure long-term sustainability of nanodevices and systems. In this study, we construct a relia-bility framework for nanoscale dielectric lms used in Metallic Oxide Semiconductor (MOS) devices. The successful fabrication and incorporation of metallic …


Advanced Signal Processing Techniques For Single Trial Electroencephalography Signal Classification For Brain Computer Interface Applications, Kun Li Dec 2010

Advanced Signal Processing Techniques For Single Trial Electroencephalography Signal Classification For Brain Computer Interface Applications, Kun Li

USF Tampa Graduate Theses and Dissertations

Brain Computer Interface (BCI) is a direct communication channel between brain and computer. It allows the users to control the environment without the need to control muscle activity [1-2]. P300-Speller is a well known and widely used BCI system that was developed by Farwell and Donchin in 1988 [3]. The accuracy level of the P300-BCI Speller as measured by the percent of communicated characters correctly identified by the system depends on the ability to detect the P300 event related potential (ERP) component among the ongoing electroencephalography (EEG) signal. Different techniques have been tested to reduce the number of trials needed …


Citizen Satellites: Tiny, Standardized Spacecraft Are Making Orbital Experiments Affordable To Even The Smallest Research Groups, Robert J. Twiggs, Alex Soojung-Kim Pang Dec 2010

Citizen Satellites: Tiny, Standardized Spacecraft Are Making Orbital Experiments Affordable To Even The Smallest Research Groups, Robert J. Twiggs, Alex Soojung-Kim Pang

Robert "Bob" Twiggs STEM Education Collection

An article written by Bob Twiggs and Alex Soojung-Kim Pang and published in the Scientific American titled "Citizen Satellites: Tiny, standardized spacecraft are making orbital experiments affordable to even the smallest research groups" from 2010.


Studies On The Preparation And Luminescence Properties Of Cadmium Selenide Quantum Dots, Their Immobilization, And Applications., Travis Justin Heath Dec 2010

Studies On The Preparation And Luminescence Properties Of Cadmium Selenide Quantum Dots, Their Immobilization, And Applications., Travis Justin Heath

Electronic Theses and Dissertations

Quantum dots are semiconductive particles whose properties are highly influenced by the presence of at least one electron. Cadmium selenide quantum dots were synthesized via colloidal synthesis. Contrary to previous preparations, more focus was placed on the temperature rather than the duration of time at which they form. A series of colored solutions were obtained because the excited quantum dots of various sizes emitted specific wavelengths of light. The emission spectra showed that the temperature-dependent quantum dots were successfully synthesized. The quantum dots were also immobilized on various surfaces, and the luminescence properties were examined. The quantum dots that were …


Reconciling Motor Performance Indicators From Theoretical Calculations And Laboratory Tests, Himanshu Hirlekar, Badrul H. Chowdhury, Stephen Ruffing Dec 2010

Reconciling Motor Performance Indicators From Theoretical Calculations And Laboratory Tests, Himanshu Hirlekar, Badrul H. Chowdhury, Stephen Ruffing

Electrical and Computer Engineering Faculty Research & Creative Works

Quite often because of the complexity in the design of large industrial motors, the theoretical motor parameter calculations do not match actual results from laboratory tests. Thus, it becomes important to predict the amount of discrepancy between the two methods to develop confidence in the motor parameter calculations. This paper discusses the development of multiple artificial neural networks (ANNs) designed to predict the ratios of measured parameters to calculated parameters, given the geometry and construction of the motor. These ratios represent correction factors which can be applied to the values calculated from the theoretical program, which, in this case, is …


Development Of A Rigid Body Computational Model For Investigation Of Wrist Biomechanics, Benjamin Majors Dec 2010

Development Of A Rigid Body Computational Model For Investigation Of Wrist Biomechanics, Benjamin Majors

Theses and Dissertations

The wrist is one of the most complex joints in the human body. As such, the wrist joint is difficult to model due to the number of bones involved and its intricate soft tissue interactions. Many studies have attempted modeling the wrist previously; however, the majority of these studies simplify the joint into two-dimensions or idealized mechanical joints to reduce the complexity of the simulation. While these approaches still yield valuable information, the omission of a third-dimension or geometry defined movements limits the models’ usefulness in predicting joint function under non-idealized conditions. Therefore, the goal of this study was to …


Evaluation Of Hydraulic Efficiency Of Disinfection Systems Based On Residence Time Distribution Curves, Jordan M. Wilson, Subhas K. Venayagamoorthy Dec 2010

Evaluation Of Hydraulic Efficiency Of Disinfection Systems Based On Residence Time Distribution Curves, Jordan M. Wilson, Subhas K. Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Hydraulic efficiency is a vital component in evaluating the disinfection capability of a contact system. Current practice evaluates these systems based upon the theoretical detention time (TDT) and the rising limb of the residence time distribution (RTD) curve. This evaluation methodology is expected because most systems are built based on TDT under a "black box" approach to disinfection system design. Within recent years, the proliferation of computational fluid dynamics (CFD) has allowed a more insightful approach to disinfection system design and analysis. Research presented in this study using CFD models and physical tracer studies shows that evaluation methods based upon …


Improving The Emulsion Stability Of Sponge Cake By The Addition Of ?-Polyglutamic Acid, Yung-Shin Shyu, Wen-Chieh Sung Dec 2010

Improving The Emulsion Stability Of Sponge Cake By The Addition Of ?-Polyglutamic Acid, Yung-Shin Shyu, Wen-Chieh Sung

Journal of Marine Science and Technology–Taiwan

The batter properties of sponge cake with the addition of γ-polyglutamic acid (PGA) at different levels (0.05, 0.1, 0.5 gkg-1, w/w) was evaluated. The viscosity, emulsion stability and foam stability increased at the addition of 0.5 gkg-1 PGA level. PGA caused significant declines in the differential scanning calorimetry (DSC) enthalpy, onset and peak temperatures of ice-melting transition of sponge cake. Sponge cakes manufactured with 0.5 gkg-1 PGA addition were in general lighter on crumb color and white index than the control. Scanning electron microscopy showed that sponge cake with the addition of 0.1 and 0.5 gkg-1 PGA exhibited microstructures having …