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Full-Text Articles in Engineering

Metal Oxide Graphene Nanocomposites For Organic And Heavy Metal Remediation, Tanvir E. Alam Mar 2012

Metal Oxide Graphene Nanocomposites For Organic And Heavy Metal Remediation, Tanvir E. Alam

USF Tampa Graduate Theses and Dissertations

This thesis consists of two research problems in the water decontamination area. In the first work, the main focus is to understand the structure and photocatalytic activity of titanium dioxide with graphene (G-TiO2) which is synthesized by using sol-gel method. The photocatalytic activity of TiO2 is limited by the short electron hole pair recombination time. Graphene, with high specific surface area and unique electronic properties, can be used as a good support for TiO2 to enhance the photocatalytic activity. The obtained G-TiO2 photocatalysts has been characterized by X-Ray Diffraction (XRD), Raman Spectroscopy, Transmission Electron Microscopy (TEM), FTIR Spectroscopy and Ultraviolet …


Effect Of Platinum Particle Size On The Sulfur Deactivation Of Hydrogenation, Lyndsey Michelle Baldyga Mar 2012

Effect Of Platinum Particle Size On The Sulfur Deactivation Of Hydrogenation, Lyndsey Michelle Baldyga

USF Tampa Graduate Theses and Dissertations

A large concern of the fossil fuel and renewable energy industries is the sulfur poisoning of catalysts. In the case of noble metals, such as platinum, it is seen that there is a size trend associated with the level of activity in the presence of sulfur. Smaller nanoparticles could be more tolerant due to sulfur surface vacancies. On the other hand, larger particles could have less deactivation because the sulfur is more attracted to the smaller particles and the sulfur molecules bind stronger to these smaller particles.

The size effect of sulfur deactivation was investigated by testing four sizes of …


The Creation Of A Robotics Based Human Upper Body Model For Predictive Simulation Of Prostheses Performance, Derek James Lura Mar 2012

The Creation Of A Robotics Based Human Upper Body Model For Predictive Simulation Of Prostheses Performance, Derek James Lura

USF Tampa Graduate Theses and Dissertations

This work focuses on the use of 3D motion capture data to create and optimize a robotic human body model (RHBM) to predict the inverse kinematics of the upper body. The RHBM is a 25 degrees of freedom (DoFs) upper body model with subject specific kinematic parameters. The model was developed to predict the inverse kinematics of the upper body in the simulation of a virtual person, including persons with functional limitations such as a transradial or transhumeral amputation. Motion data were collected from 14 subjects: 10 non-amputees control subjects, 1 person with a transradial amputation, and 3 persons with …


Water Quality Monitoring In A Pilot Marine Integrated Aquaculture System, Alex W. Kruglick Mar 2012

Water Quality Monitoring In A Pilot Marine Integrated Aquaculture System, Alex W. Kruglick

USF Tampa Graduate Theses and Dissertations

Land based aquaculture systems are growing in popularity, and there is a drive to improve the efficiency of their energy and water systems for both economic and environmental benefit. Recirculating Aquaculture Systems (RAS) generally refer to systems that recycle their wastewater streams to be more or less a zero discharge facility. A more sustainable approach is emerging in the form of Integrated Aquaculture Systems (IAS) where maximum utility is realized from the various components so that fresh water use is reduced, water quality is improved, energy use is reduced, and new markets are created or fulfilled. Under a grant from …


A Multifaceted Analysis Of Early Stage Non-Small Cell Lung Cancer Data, Madhusmita Behera Feb 2012

A Multifaceted Analysis Of Early Stage Non-Small Cell Lung Cancer Data, Madhusmita Behera

USF Tampa Graduate Theses and Dissertations

Some early stage NSCLC patients have a better survival prospects than others. In any event, the long-term prognosis for NSCLC patients is poor. Various measures were investigated to gain a better understanding of those patient characteristics that confer better survival or predict disease recurrence. A dataset comprised of stage 1 NSCLC patients (n=162) that underwent resection was investigated. Clinical variables (CVs) and tissue microarray (TMA) images with DNA repair protein and standard H&E expressions were investigated. Patients were dichotomized into two groups by survival characteristics and logistic regression (LR) modeling was used to predict favorable survival outcome. Various patient strata …


Synthesis And Characterization Of Nanocomposites For Electrochemical Capacitors, Farah Alvi Feb 2012

Synthesis And Characterization Of Nanocomposites For Electrochemical Capacitors, Farah Alvi

USF Tampa Graduate Theses and Dissertations

Presently there are deep concerns over the environmental consequences and the consumption of non-renewable energy sources, with the accelerated greenhouse effect, triggered enormous interest in the use of renewable energy sources e.g., solar, hydropower, wind and geothermal. However the intermittent nature of harvesting renewable energy sources has recently gained considerable attention in the alternative reliable, cost effective, and environmentally friendly energy storage devices. The supercapacitor and lithium ion batteries are considered more efficient electrical energy storage devices than conventional energy storage systems.

Both devices have many useful and important applications; they could be an excellent source for high power and …


Multistable Shape-Shifting Surfaces (Mssss), Paul Joseph Montalbano Jan 2012

Multistable Shape-Shifting Surfaces (Mssss), Paul Joseph Montalbano

USF Tampa Graduate Theses and Dissertations

This paper presents designs for Multistable Shape-Shifting Surfaces (MSSS) by introducing bistability into the Shape-Shifting Surface (SSS). SSSs are defined as surfaces that retain their effectiveness as a physical barrier while undergoing changes in shape. The addition of bistability to the SSS gives the surface multiple distinct positions in which it remains when shifted to, i.e. by designing bistability into a single SSS link, the SSS unit cell can change into multiple shapes, and stabilize within the resulting shape, while maintaining integrity against various forms of external assaults normal to its surface. Planar stable configurations of the unit cell include, …


Design Of A Reversible Alu Based On Novel Reversible Logic Structures, Matthew Arthur Morrison Jan 2012

Design Of A Reversible Alu Based On Novel Reversible Logic Structures, Matthew Arthur Morrison

USF Tampa Graduate Theses and Dissertations

Programmable reversible logic is emerging as a prospective logic design style for implementation in modern nanotechnology and quantum computing with minimal impact on circuit heat generation. Recent advances in reversible logic using and quantum computer algorithms allow for improved computer architecture and arithmetic logic unit designs. In this paper, a 2*2 Swap gate which is a reduced implementation in terms of quantum cost and delay to the previous Swap gate is presented. Next, a novel 3*3 programmable UPG gate capable of calculating the fundamental logic calculations is presented and verified, and its advantages over the Toffoli and Peres gates are …


Estimation Of The Impact Of Single Airport And Multi-Airport System Delay On The National Airspace System Using Multivariate Simultaneous Models, Nagesh Nayak Jan 2012

Estimation Of The Impact Of Single Airport And Multi-Airport System Delay On The National Airspace System Using Multivariate Simultaneous Models, Nagesh Nayak

USF Tampa Graduate Theses and Dissertations

Airline delays lead to a tremendous loss of time and resources and cost billions of dollars every year in the United States (U.S.). At certain times, individual airports become bottlenecks within the National Airspace System (NAS). To explore solutions for reducing the delay, it is essential to understand factors causing flight delay and its impact on airports in the NAS. Major causal factors of flight delay at airports include over-scheduling, en-route convective weather, reduced ceiling and visibility around airports, and upstream delay propagation. Delay at one airport can be passed on to other airports in the NAS, in another word, …


Volume-Phase Transitions In Responsive Photo-Cross-Linked Polymer Network Films, Leena Patra Jan 2012

Volume-Phase Transitions In Responsive Photo-Cross-Linked Polymer Network Films, Leena Patra

USF Tampa Graduate Theses and Dissertations

The overall thrust of this project is to gain an insight into a class of surface-tethered cross-linked thin films of poly(N-alkylacrylamides) that display a lower critical solution temperature (LCST).The structure of the alkyl group and the modification of the amide groups determine the LCST and resultant volume-phase transition behavior. The aim of this study involves synthesis and characterization of thin films and to correlate the volume-transition behavior to the structure of the alkyl group. For better understanding the volume-transition behavior, the polymer films are perturbed by the Hofmeister salt series to examine trends between different alkyl groups. While most of …


Macroencapsulation Of Phase Change Materials For Thermal Energy Storage, Swetha Pendyala Jan 2012

Macroencapsulation Of Phase Change Materials For Thermal Energy Storage, Swetha Pendyala

USF Tampa Graduate Theses and Dissertations

The use of a latent heat storage system using phase change materials (PCMs) is an effective way of storing thermal energy. Latent heat storage enables high-energy storage density which reduces the footprint of the system and the cost. However, PCMs have very low thermal conductivities making them unsuitable for large-scale use without enhancing the effective thermal conductivity. In order to address, the low thermal conductivity of the PCMs, macroencapsulation of PCMs has been adopted as an effective technique. The macroencapsulation not only provides a self-supporting structure of PCM and separates the PCM from thermal fluids but also enhances the heat …


Field And Laboratory Comparison Of The Hydraulic Performance Of Two Ceramic Pot Water Filters, Duncan Peabody Jan 2012

Field And Laboratory Comparison Of The Hydraulic Performance Of Two Ceramic Pot Water Filters, Duncan Peabody

USF Tampa Graduate Theses and Dissertations

Currently 884 million people worldwide are living without access to an improved source of drinking water (WHO/UNICEF, 2011). Piped-water on premises is the ultimate goal of World Health Organization (WHO) due to the ability to treat all of the water and distribute it safely in pressurized pipes. However, Household Water Treatment and Safe Storage (HWTS) is an option for improving the quality of drinking water where that infrastructure is not yet developed, especially where there is a risk of recontamination between point of collection and point of use (Clasen, 2006).

This study analyzed one such HWTS, the ceramic pot water …


A Statically Balanced Shape-Shifting Surface, Joseph Eugene Pishnery Jan 2012

A Statically Balanced Shape-Shifting Surface, Joseph Eugene Pishnery

USF Tampa Graduate Theses and Dissertations

ABSTRACT

This paper presents a concept for producing a Statically Balanced Shape-Shifting Surface (SB-SSS). In this context, an SB-SSS is a surface that can require near-zero magnitude force changes to accomplish a change in shape while retaining effectiveness as a physical barrier. This paper focuses on how to statically balance a specifically-designed compliant mechanism and how to incorporate this mechanism into a polygonal cell.

The mechanism consists of a compliant Peaucellier-Lipkin linkage layered with a pre-stressed link as the balancer. Previous work is presented that can show how a polygonal cell can be incorporated into a surface via a tiling …


Novel Blends Of Sulfur-Tolerant Water-Gas Shift Catalysts For Biofuel Applications, Timothy Michael Roberge Jan 2012

Novel Blends Of Sulfur-Tolerant Water-Gas Shift Catalysts For Biofuel Applications, Timothy Michael Roberge

USF Tampa Graduate Theses and Dissertations

As traditional sources of energy become depleted, significant research interest has gone into conversion of biomass into renewable fuels. Biomass-derived synthesis gas typically contains concentrations of approximately 30 to 600 ppm H2S in stream. H2S is a catalyst poison which adversely affects downstream processing of hydrogen for gas to liquid plants. The water-gas shift reaction is an integral part of converting CO and steam to H2 and CO2. Currently, all known water-gas shift catalysts deactivate in sulfur concentrations typical of biomass-derived synthesis gas. Novel catalysts are needed to remain active in the presence of sulfur concentrations in order to boost …


Cell Adhesion And Migration On Ndga Cross-Linked Fibrillar Collagen Matrices For Tendon Tissue Engineering, Ana Ysabel Rioja Jan 2012

Cell Adhesion And Migration On Ndga Cross-Linked Fibrillar Collagen Matrices For Tendon Tissue Engineering, Ana Ysabel Rioja

USF Tampa Graduate Theses and Dissertations

Tendons, essential tissues that connect muscles to bones, are susceptible to rupture/degeneration due to their continuous use for enabling movement. Often surgical intervention is required to repair the tendon; relieving the pain and fixing the limited mobility that occurs from the damage. Unfortunately, post-surgery immobilization techniques required to restore tendon properties frequently lead to scar formation and reduced tendon range of motion. Our ultimate goal is to create an optimal tendon prosthetic that can stabilize the damaged muscle-bone connection and then be remodeled by resident cells from the surrounding tissues over time to ensure long-term function. To achieve this, we …


Analysis And Optimization Of Broadband Measurement Cells For The Characterization Of Dielectric Polymer Films, Scott Skidmore Jan 2012

Analysis And Optimization Of Broadband Measurement Cells For The Characterization Of Dielectric Polymer Films, Scott Skidmore

USF Tampa Graduate Theses and Dissertations

The current techniques and methodologies used in the field of material characterization are well documented and widely accepted as reliable and accurate. However, literature describing these techniques focuses on the algorithms used during material characterization; few studies have reposted on the design of, and the selection criteria for, the test fixtures themselves. This research focuses on the measurement cell with the goal of determining the sensitivity of the measurement cell to the addition of a thin film material.

Microstrip and coplanar waveguide were chosen for the analysis, which included three configurations of each transmission line geometry: a reference with no …


On The Development Of The Extradosed Bridge Concept, Steven Lynn Stroh Jan 2012

On The Development Of The Extradosed Bridge Concept, Steven Lynn Stroh

USF Tampa Graduate Theses and Dissertations

The Extradosed Prestressed Bridge represents a relatively new bridge type. The first of this type bridge was constructed in Japan in 1994, and Japan has since built at least 29 examples of this bridge type. Throughout the rest of the world, another 34 of this bridge type have been built, with most countries having only one, or at most a few, examples. A broader application of this bridge type has been hampered by lack of design information and in particular lack design criteria for the stay cables. The purpose of this dissertation is to progress the understanding and application of …


Analysis And Remediation Of Chlorinated Hydrocarbons In Environmental Media, Jonathan Ticknor Jan 2012

Analysis And Remediation Of Chlorinated Hydrocarbons In Environmental Media, Jonathan Ticknor

USF Tampa Graduate Theses and Dissertations

The two objectives of this work were to develop a simplified method for the analysis of chlorinated organics in water samples and to improve an existing soil remediation technology. The contaminants considered for these studies were chlorinated hydrocarbons because of their relative frequency of appearance at contaminated sites. The first half of this study involved the analysis of chlorinated ethenes by gas chromatography with flame ionization detection (GC-FID). I tested the hypothesis that the FID response factor is the same for all chlorinated ethene compounds. The rationale for this investigation is that if the hypothesis is correct, a single calibration …


Experimental And Numerical Investigation Of An Electrospray Rf Ion Funnel, Eric Miguel Tridas Jan 2012

Experimental And Numerical Investigation Of An Electrospray Rf Ion Funnel, Eric Miguel Tridas

USF Tampa Graduate Theses and Dissertations

Using experimental techniques along with computational fluid dynamics and electrodynamic simulations the performance of the first of three focusing elements in an electrospray macromolecular patterning system was assessed. The performance of this element, the ion funnel, was analyzed by varying the parameters and electric field applied to the system including electrospray emitter to atmosphere-vacuum interface capillary distance, temperature of the desolvating heater, injection rate of solution and the voltage applied to the jet disruption element. Results indicated that processes involved in injecting larger droplets into the chamber resulted in a less effective transmission of the ions through the funnel. Droplet …


Synthesis And Physical Properties Of Group 14 Intermetallic Clathrates, Stevce Stefanoski Jan 2012

Synthesis And Physical Properties Of Group 14 Intermetallic Clathrates, Stevce Stefanoski

USF Tampa Graduate Theses and Dissertations

The search of materials relevant for thermoelectric and magnetocaloric applications, as well as materials that interact with light, is an important aspect of the materials science. Such materials can be used for solid-state power generation and refrigeration, as light sources, detectors, or controllers. Intermetallic clathrates have long been of interest for the materials science research. The promise these materials hold for useful applications ranges from thermoelectrics to photovoltaics and optoelectronics to potentially ultra-hard materials and magnetic cooling applications. Their unique physical properties are intimately related to their intriguing structural properties. Thus a fundamental understanding of the chemistry and physics of …


Shelf-Scale Mapping Of Fish Distribution Using Active And Passive Acoustics, Carrie Christy Wall Jan 2012

Shelf-Scale Mapping Of Fish Distribution Using Active And Passive Acoustics, Carrie Christy Wall

USF Tampa Graduate Theses and Dissertations

Fish sound production has been associated with courtship and spawning behavior. Acoustic recordings of fish sounds can be used to identify distribution and behavior. Passive acoustic monitoring (PAM) can record large amounts of acoustic data in a specific area for days to years. These data can be collected in remote locations under potentially unsafe seas throughout a 24-hour period providing datasets unattainable using observer-based methods. However, the instruments must withstand the caustic ocean environment and be retrieved to obtain the recorded data. This can prove difficult due to the risk of PAMs being lost, stolen or damaged, especially in highly …


Catalytic Tri-Reforming Of Biomass-Derived Syngas To Produce Desired H2:Co Ratios For Fuel Applications, Devin Mason Walker Jan 2012

Catalytic Tri-Reforming Of Biomass-Derived Syngas To Produce Desired H2:Co Ratios For Fuel Applications, Devin Mason Walker

USF Tampa Graduate Theses and Dissertations

This study focuses on upgrading biomass derived syngas for the synthesis of liquid fuels using Fischer-Tropsch synthesis (FTS). The process includes novel gasification of biomass via a tri-reforming process which involves a synergetic combination of CO2 reforming, steam reforming, and partial oxidation of methane. Typical biomass-derived syngas H2:CO is 1:1 and contains tars that deactivate FT catalyst. This innovation allows for cost-effective one-step production of syngas in the required H2:CO of 2:1 with reduction of tars for use in the FTS. To maximize the performance of the tri-reforming catalyst, an attempt to control oxygen mobility, thermal stability, dispersion of metal, …


The Electronic Structure Of Biomolecular Self-Assembled Monolayers, Matthaeus Anton Wolak Jan 2012

The Electronic Structure Of Biomolecular Self-Assembled Monolayers, Matthaeus Anton Wolak

USF Tampa Graduate Theses and Dissertations

The studies presented here address the characterization of the electronic structure of various self-assembled monolayers (SAMs) of peptide nucleic acid (PNA) and tetraphenylporphyrin (TPP) SAMs and arrays, formed on gold substrates.

PNA is a promising alternative to DNA for bio-sensing applications, as well as for strategies for self-assembly based on nucleic acid hybridization. In recent years charge transfer through PNA molecules was a focus of research due to possible applications in self-assembled molecular circuits and molecular tools. In light of this research it is interesting to investigate the electronic structure of PNA interfaces to gold, a potential electrode material.

TPP …


Effects Of Random Cross-Sectioned Distributions, Fiber Misalignment And Interphases In Three-Dimensional Composite Models On Transverse Shear Modulus, Jarrett Zitko Jan 2012

Effects Of Random Cross-Sectioned Distributions, Fiber Misalignment And Interphases In Three-Dimensional Composite Models On Transverse Shear Modulus, Jarrett Zitko

USF Tampa Graduate Theses and Dissertations

Finite element analysis was implemented to evaluate the transverse shear modulus of a unidirectional glass/epoxy fiber-matrix composite based on pure shear displacement boundary conditions. Unit cells consisting of three-dimensional glass cylinders surrounded in square-cuboid epoxy matrices were modeled to represent "Representative Volume Element" (RVE) configurations in periodic and random-periodic square cell arrangements of variable size. Three RVEs were constructed and analyzed: A single unit cell, a 9-cell (3 x 3) array, and a 25-cell (5 x 5) array. Additionally, the unit cell was modeled to include an interphase. Three sets of cell arrangements were constructed and evaluated: a periodic square …


Direct Verification Of The Locking Of Liquid Locking Compounds In Threaded Fasteners, Ryan Hunter Jan 2012

Direct Verification Of The Locking Of Liquid Locking Compounds In Threaded Fasteners, Ryan Hunter

USF Tampa Graduate Theses and Dissertations

The motivation of this research is to explore the viability of a method to directly verify whether or not an anaerobic adhesive within a threaded fastener assembly has cured sufficiently to provide secondary locking. Direct verification was implemented via the application of a test torque in the loosening direction of a fastener assembly with Loctite (given a 24 hour cure time). A three phase test plan was developed with the intent of identifying and utilizing this verification torque value which is unique to a given fastener assembly.

It was proved that the direct verification method, as outlined in the test …


Design Of Contact Line Friction Measurement Machine Apparatus, Seyed Kamran Najafi Jan 2012

Design Of Contact Line Friction Measurement Machine Apparatus, Seyed Kamran Najafi

USF Tampa Graduate Theses and Dissertations

The purpose of this project is to design and manufacture a high precision machine to directly measure the surface force of fluids. Knowing how to move droplets easier with less resistance can increase the potential of a wide range of applications and improve the performance of things such as self-assembly applications. This machine has the ability to measure forces of up to 100 N with a MEMS based sensor. The motion system on this machine moves a substrate underneath of a droplet for 100 mm and applies dragging force to the sensor. It moves with a controlled speed with high …


Encapsulation Of High Temperature Phase Change Materials For Thermal Energy Storage, Rupa Nath Jan 2012

Encapsulation Of High Temperature Phase Change Materials For Thermal Energy Storage, Rupa Nath

USF Tampa Graduate Theses and Dissertations

Thermal energy storage is a major contributor to bridge the gap between energy demand (consumption) and energy production (supply) by concentrating solar power. The utilization of high latent heat storage capability of phase change materials is one of the keys to an efficient way to store thermal energy. However, some of the limitations of the existing technology are the high volumetric expansion and low thermal conductivity of phase change materials (PCMs), low energy density, low operation temperatures and high cost. The present work deals with encapsulated PCM system, which operates at temperatures above 500°C and takes advantage of the heat …


Optimization Of Bio-Impedance Sensor For Enhanced Detection And Characterization Of Adherent Cells, Dorielle T. Price Jan 2012

Optimization Of Bio-Impedance Sensor For Enhanced Detection And Characterization Of Adherent Cells, Dorielle T. Price

USF Tampa Graduate Theses and Dissertations

This research focuses on the detection and characterization of cells using

impedance-based techniques to understand the behavior and response of cells to internal/environmental changes. In combination with impedimetric sensing techniques, the biosensors in this work allow rapid, label-free, quantitative measurements and are very sensitive to changes in environment and cell morphology. The biosensor design and measurement setup is optimized to detect and differentiate cancer cells and healthy (normal) cells. The outcome of this work will provide a foundation for enhanced 3-dimensional tumor analysis and characterization; thus creating an avenue for earlier cancer detection and reduced healthcare costs.

The magnitude of …


Smart Packaging: A Novel Technique For Localized Drug Delivery For Ovarian Cancer, Eva Christabel Williams Jan 2012

Smart Packaging: A Novel Technique For Localized Drug Delivery For Ovarian Cancer, Eva Christabel Williams

USF Tampa Graduate Theses and Dissertations

Localized drug delivery is emerging as an effective technique due to its ability to administer therapeutic concentrations and controlled release of drugs to cancer sites in the body. It also prevents the contact of harsh chemotherapy drugs to healthy regions in the body that otherwise would become exposed to current treatments.

This study reports on a model chemotherapy drug delivery system comprising non-ionic surfactant vesicles (niosomes) packaged within a temperature-sensitive chitosan network. This smart packaging, or package-within-a package system, provides two distinct advantages. First, the gel prevents circulation of the niosomes and maintains delivery in the vicinity of a tumor. …