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Pd-Based Photocatalysts For Sonogashira C-C Cross-Coupling Reactions, Komadhie Charuka Dissanayake Jan 2018

Pd-Based Photocatalysts For Sonogashira C-C Cross-Coupling Reactions, Komadhie Charuka Dissanayake

Masters Theses

Sonogashira C-C cross-coupling reaction has been heavily used for its simplicity, flexibility and value. Although the original Sonogashira C-C cross coupling reaction conditions entail the use of 0.5 mol% of Pd catalyst, 2 mol% of Cul as co-catalyst at room temperature, the experimental conditions used in laboratories to prepare some compounds vary substantially, especially with respect to the reaction time, temperature and loading amount of the catalysts. The most significant drawback of the conventional Sonogashira reaction is the use of Cul as it leads to the formation of homocoupling product when the reaction is exposed to air or oxidizing agents. …


Distiphallus Morphology And Its Role In Copulation Dynamics In Anastrepha Suspensa (Loew), Taylor J. Inboden Jan 2018

Distiphallus Morphology And Its Role In Copulation Dynamics In Anastrepha Suspensa (Loew), Taylor J. Inboden

Masters Theses

Anastrepha suspensa (Diptera; Tephritidae) is an agricultural pest species causing severe economic damage and is controlled, in part, by applying knowledge of this species' reproduction (e.g., disrupting fertile copulations by SIT). During copulation, males transfer sperm as well as protein rich fluids through an aedeagus and distiphallus, which females then store in three spermathecae and one ventral receptacle. Within the female reproductive tract, the ventral receptacle and the three spermathecae are strategically separated from each other. I hypothesized males' ability to direct sperm transfer within the female reproductive tract is through the structures found in the distiphallus. Utilizing scanning electron …


Only In It For The News: Satire Television Pilot Critiquing The Structure Of Television News, Dakota Pruemer Jan 2018

Only In It For The News: Satire Television Pilot Critiquing The Structure Of Television News, Dakota Pruemer

Masters Theses

Televisual satire news is currently a way for the creators of the programming to critique what is being said in broadcast news media. I think that satire should go a step further and also critique how broadcast news media works. In order to do this, I created a television pilot that breaks the paradigm in which television news operates. Only in it for the News is a creative thesis that incorporates communication and media theory with production techniques to create a television pilot that critiques television news and provides an alternative approach to how television satire is typically presented. The …


The Relationship Between Resilience, Coping, And Social Media, Lillian N. Hurley Jan 2018

The Relationship Between Resilience, Coping, And Social Media, Lillian N. Hurley

Masters Theses

This study was designed to explore relationships between measures of resilience, coping strategies, social media usage, and depression. Resilience refers to one's ability to endure and recover from adversity. Many theories about what contributes to the development resilience have been explored without a clear consensus. Taormina (2015) argued that adult personal resilience is comprised of four dimensions - determination, endurance, adapatability, and recuperability. Coping, a construct related to resilience, is the process of regulating emotions, cognition, behavior, physiological responses, and the environment in response to stressful events. Past research indicated those with poorer mental health have the tendency to use …


Efficient Implementation Of Ieee 802.11i Wi-Fi Security (Wpa2-Psk) Standard Using Fpga, Atal Bajracharya Jan 2018

Efficient Implementation Of Ieee 802.11i Wi-Fi Security (Wpa2-Psk) Standard Using Fpga, Atal Bajracharya

Masters Theses

The rationale behind the thesis was to design efficient implementations of cryptography algorithms used for Wi-Fi Security as per IEEE 802.11i Wi-Fi Security (WPA2-PSK) standard. The focus was on software implementation of Password-Based Key Derivation Function 2 (PBKDF2) using Keyed-Hash Message Authentication Code (HMAC)-SHA1, which is used for authentication, and, hardware implementation of AES-256 cipher, which is used for data confidentiality.

In this thesis, PBKDF2 based on HMAC-SHA1 was implemented on software using C programming language, and, AES-256 was implemented on hardware using Verilog HDL. The overall implementation was designed and tested on Nexys4 FPGA board. The performance of the …


Laser-Aided Additive Manufacturing Of Glass, John Michael Hostetler Jan 2018

Laser-Aided Additive Manufacturing Of Glass, John Michael Hostetler

Masters Theses

“This thesis presents various approaches for the laser-aided additive manufacturing of glass. First, a technique is investigated to create free-form, low to zero coefficient of thermal expansion structures out of silica-gel. A CO2 laser was coupled through a gantry system and focused onto a binder-free silica-gel powder bed (15-40 μm particles). Prior to writing each layer, powder is dispensed by sifting it onto the build platform as opposed to a conventional wiper system, avoiding contacting and potentially damaging sensitive parts. After deposition, the parts are annealed in a furnace to increase their strength. The influence of various process parameters …


System Level Power Integrity Transient Analysis Using A Physics-Based Approach, Jun Xu Jan 2018

System Level Power Integrity Transient Analysis Using A Physics-Based Approach, Jun Xu

Masters Theses

"With decreasing supply voltage level and massive demanding current on system chipset, power integrity design becomes more and more critical for system stability. The ultimate goal of well-designed power delivery network (PDN) is to deliver desired voltage level from the source to destination, in other words, to minimize voltage noise delivered to digital devices. The thesis is composed of three parts. The first part focuses on-die level power models including simplified chip power model (CPM) for system level analysis and the worst scenario current profile. The second part of this work introduces the physics-based equivalent circuit model to simplify the …


Coaxial Cable Ring Resonator Based On Pair Sided Coaxial Cable Bragg Grating Coupler For Sensing Appllication, Xiaotong Tang Jan 2018

Coaxial Cable Ring Resonator Based On Pair Sided Coaxial Cable Bragg Grating Coupler For Sensing Appllication, Xiaotong Tang

Masters Theses

“Coaxial cable based devices, such as coaxial cable Bragg grating (CCBG), coiled coaxial cable resonator have been demonstrated for sensing applications to address the challenges faced by fiber optic sensors (e.g., large strain survivability, installation). Inspired by the fiber ring resonator (FRR), coaxial cable based ring resonator (CCRR) is reported in this thesis. The device mainly formed by a homemade coaxial cable Bragg grating (CCBG) pair based side coupler. Comparing to the commercial coupler, CCBG-SC improves the flexibility of the device for sensing applications. The coupling frequency of the CCBG-based coupler can be modified by changing the grating length and …


Distributed Fiber Optic Sensors For Monitoring Spatially Continuous Strain And Quasi-Distributed Refractive Index Using Optical Frequency Domain Reflectometry, Sasi Jothibasu Jan 2018

Distributed Fiber Optic Sensors For Monitoring Spatially Continuous Strain And Quasi-Distributed Refractive Index Using Optical Frequency Domain Reflectometry, Sasi Jothibasu

Masters Theses

"This thesis is comprised of two papers and they describe distributed fiber optic sensing using an optical frequency domain reflectometry (OFDR) instrumentation system.

The first paper presents about distributed fiber optic sensor embedded within the layers of a composite laminates to monitor the continuous profile of strain using the optical frequency domain reflectometry (OFDR) system. The OFDR system was used to analyze the Rayleigh backscattered signal. The shift in the Rayleigh backscattered spectrum (RBS) was observed to be linearly related to the change in strain of the composite material. The continuous strain sensing using OFDR was demonstrated by an INSTRON …


Advanced Process To Embed Optical Fiber Sensors Into Casting Mold For Smart Manufacturing, Raghavender Reddy Jakka Jan 2018

Advanced Process To Embed Optical Fiber Sensors Into Casting Mold For Smart Manufacturing, Raghavender Reddy Jakka

Masters Theses

"Optical fiber sensors embedded in metals with distributed sensing can sense temperature at multiple points with single fiber. This is useful for smart manufacturing like structural health monitoring in aerospace industry and smart molds in manufacturing plants. There is a huge difference in thermal coefficient of expansion for fiber and metal. This is the reason for the increase in sensitivity for embedded fiber sensors. However, at high temperatures, the stress on the fiber increases, eventually damaging the sensor. The fiber-metal interface determines the sensor performance. A tight interface results in high sensitivity and a gap in the interface enhances sensing …


Development Of Hollow Coaxial Cable Fabry Perot Resonator For High Temperature Sensing Applications, Mohammed Farhan Ahmed Jan 2018

Development Of Hollow Coaxial Cable Fabry Perot Resonator For High Temperature Sensing Applications, Mohammed Farhan Ahmed

Masters Theses

"The thesis is comprised of two papers, the first paper presents the novel High-Quality Factor Coaxial Cable Fabry-Perot Resonator for sensing applications. The sensor is fabricated by creating two highly reflective mirrors in a coaxial cable. The temperature response of the sensor was tested, by monitoring the frequency shift of the reflection spectra as the temperature increased linearly from 35 °C to 80 °C in steps of 5 °C. The sensor exhibited high temperature sensitivity and good measurement resolution.

A high Q factor of 133 was recorded. The second paper in the thesis presents a low cost, robust, homemade hollow …


Corrosion Performance Of Zirconium-Based Passivations On Electroplated Zinc Nickel, Madison Morgan Reed Jan 2018

Corrosion Performance Of Zirconium-Based Passivations On Electroplated Zinc Nickel, Madison Morgan Reed

Masters Theses

“Performance requirements for Department of Defense (DoD) electrical components include corrosion and electrical contact resistance. Historically, electroplated cadmium with a chromate conversion coating (CrCC) has been used to meet corrosion and contact resistance standards. However, replacements are needed for these materials because they are toxic and carcinogenic. Electroplated γ-ZnNi has been identified as an acceptable alternative to Cd. This study evaluated commercially available Zr-based thin films and sealers as passivations for potential replacement of CrCCs. Ten different passivations were tested and compared with bare γ-ZnNi. X-Bond and Zircobond passivations were found to provide some improvement to the bare ZnNi corrosion …


Untangling The Effects Of Biosynthetic And Metabolic Rates On Oxidative Cellular Damage In An Insect Model, Nikki Jihui Gomez Jan 2018

Untangling The Effects Of Biosynthetic And Metabolic Rates On Oxidative Cellular Damage In An Insect Model, Nikki Jihui Gomez

Masters Theses

“Previously, a theoretical model for unravelling the entwined effects of metabolic and biosynthetic rates on oxidative cellular damage accumulation during an animal’s growth period was developed and tested in hornworms (Manduca sexta larvae). In theory, if an animal had unrestricted amounts of energy and a high repair efficiency, they could repair most of the oxidative cellular damage accumulated, regardless of how their metabolic rate varies. However, organisms have a finite amount of energy that is allocated to repair and, during the animal’s development period, a considerable amount of energy goes towards growth eliciting a tradeoff between biosynthesis and repair. …


Effect Of Variation Of Parameters On Biogas Production Using Aspen Plus & Dynamic Simulation Using Mimic, Shruti Shrikant Karambelkar Jan 2018

Effect Of Variation Of Parameters On Biogas Production Using Aspen Plus & Dynamic Simulation Using Mimic, Shruti Shrikant Karambelkar

Masters Theses

"Design and management for Biogas production have gained significance in growing dependency on Renewable energy resources. This would need a detailed information on steady state and dynamic behavior of systems. In order to make this process environmentally ecofriendly, its needs a lot of improvisation on process simulation. Anaerobic digestion helps treat this inefficient water to be converted into water fit for effluent purposes.

Byproducts contain consists of organic, inorganic and wastes which lead to a high COD content and thus, cannot be discarded into the outlets. The anaerobic digestion process. A study of these effects with simulation need to be …


Bioaccessibility Of Lead From Contaminated Soil Using Phosphate Treatment -- Physiologically Based Extraction Test And In Vitro Gastrointestinal Method Test, Austin Charles Doss Jan 2018

Bioaccessibility Of Lead From Contaminated Soil Using Phosphate Treatment -- Physiologically Based Extraction Test And In Vitro Gastrointestinal Method Test, Austin Charles Doss

Masters Theses

"Phosphate treatments are used to immobilize lead in soil by forming pyromorphite. Soil from Bonne Terre, Mo was collected to study whether such treatment decreases the bioaccessibility of lead. The soil was treated using 0.5 soil wt% of phosphate. Treatments were: none, phosphoric acid, triple super phosphate, and organic bone meal. Each sample was studied after one, four, sixteen, and twenty weeks; during this time span, water was added approximating the average rainfall rate. Percolated water was collected to test the leached phosphate concentrations. Phosphate was below the detection limit in that leachate. Remediated soil samples were used in Physiologically …


New Wellbore-Integrity Classification For Gas Migration Problems And New Cement Formulations Using Graphene Nano Platelets To Prevent Gas Migration Through Cement, Mohammed Mousa M. Alkhamis Jan 2018

New Wellbore-Integrity Classification For Gas Migration Problems And New Cement Formulations Using Graphene Nano Platelets To Prevent Gas Migration Through Cement, Mohammed Mousa M. Alkhamis

Masters Theses

"Gas migration, one of the primary problems related to the integrity of oil wells, is caused by cement failures. Gas migration can result in costly well repairs and may endanger personal, equipment, and result in severe operational difficulties and environmental issues. The ultimate objectives of this research were to provide a comprehensive review of the problem and to provide a solution to the problem using Graphene Nano Platelets (GNPs).

An intensive review was performed to understand the cement failures. The reasons behind these failures were analyzed and classified with respect to their locations in the wellbore. Recommendations and potential solutions …


Methodology For 3d Full-Wave Simulation Of Electrostatic Breakdown Across An Air Gap, Darwin Zhang Li Jan 2018

Methodology For 3d Full-Wave Simulation Of Electrostatic Breakdown Across An Air Gap, Darwin Zhang Li

Masters Theses

"The Rompe-Weizel SPICE model is used to obtain the time dependent arc resistance during simulation of air gap discharge. The SPICE model is solved using a circuit simulator, and the accompanying 3D model is solved using the transmission-line matrix time domain numerical method. Transient co-simulation is a new technique that is used to solve both circuit and 3D models at the same time. Transient co-simulation with the Rompe-Weizel SPICE model is first validated for different arc lengths using a simple geometry of a rod discharging to a ground plane. Validation is achieved by comparing the discharge currents from simulation with …


Recycling Effect In Expanded Granular Sludge Bed Reactor And Implementation Of Six Sigma In A Methane Generation Process, Manohar Manchenahalli Shivashankaraiah Jan 2018

Recycling Effect In Expanded Granular Sludge Bed Reactor And Implementation Of Six Sigma In A Methane Generation Process, Manohar Manchenahalli Shivashankaraiah

Masters Theses

"Brewery industries are the largest consumers of water among several production industries. Despite consuming these huge amounts of water and electricity, they generate by-products that are harmful to the environment. These by-products contain organic, inorganic, and solid wastes with high chemical oxygen demand (COD) strength. The anaerobic digestion (AD) process plays an important role in treating this wastewater. This study investigates the design and development of an expanded granular sludge bed reactor (EGSB) effluent recirculation, which can achieve high COD removal efficiency of the wastewater and enhance the efficiency of generating biogas with high yields and increases in the concentration …


Loss Of Trust: The Negative Effects Of Leader Discrimination And The Mitigating Effects Of Organizational Response, Andrew Wade Pepper Jan 2018

Loss Of Trust: The Negative Effects Of Leader Discrimination And The Mitigating Effects Of Organizational Response, Andrew Wade Pepper

Masters Theses

"This thesis focuses on how perceptions of leader discriminatory behavior influence trust in the leader and, subsequently, attitudes about the organization which the leader represents. This study builds on previous research findings by creating a 2 (discriminatory interaction) X 2 (procedural response) X 2 (distributive response) experimental design model with vignettes that focused a leader's discriminatory or non-discriminatory behaviors and how the organization responds to accusations of such behavior. Participants (N = 293) were recruited from Amazon Mechanical Turk and randomly assigned to read one of the two vignettes describing a supervisor's discriminatory or non-discriminatory behavior. After reporting perceptions shaped …


Investigation Of The Information Provided By Light Touch For Balance Improvement In Humans, Anirudh Saini Jan 2018

Investigation Of The Information Provided By Light Touch For Balance Improvement In Humans, Anirudh Saini

Masters Theses

"This study investigates the information provided by Light Touch (LT) in improving human postural stability without mechanical assistance. Light Touch, an interaction force with a magnitude about 1 N, is known to improve postural stability in humans during quiet standing. However, the nature of the information from LT that helped improve balance is yet unknown. In this work, we hypothesized that LT provides information about one's body kinematics. We used a haptic robot to provide modulated, measurable light interaction force on the high back haptic location of humans to provide body kinematics-dependent information through LT. Standing balance experiments were performed …


An Approach For Formal Analysis Of The Security Of A Water Treatment Testbed, Sai Sidharth Patlolla Jan 2018

An Approach For Formal Analysis Of The Security Of A Water Treatment Testbed, Sai Sidharth Patlolla

Masters Theses

"This thesis focuses on securing critical infrastructures such as chemical plants, manufacturing units, and power generating plants against attacks that disrupt the information flow from one component to another. Such systems are controlled by an Industrial Control System (ICS) that includes controllers communicating with each other, and with physical sensors and actuators, using a communications network.

Traditional security models partition the security universe into two worlds, secure and insecure, but in the real world the partitions often overlap and information is leaked even through the physical observation which makes it much harder to analyze a Cyber physical system (CPS). To …


Cellular Hitchhiking Via Injectable Microparticles, Daniel Smith Jan 2018

Cellular Hitchhiking Via Injectable Microparticles, Daniel Smith

Masters Theses

"Tissue engineering is a process of developing new tissues in a host. Tissue engineering draws upon revitalizing damaged tissues that otherwise would not heal completely from the body's natural response. To augment the body's natural response to impairment, cells can be transplanted to the afflicted area to boost the healing response. Implementing these cells onto scaffolds and transplanting them into the body improves the healing response dramatically. Tissue regeneration improves when a biodegradable scaffold is used in conjunction with cells to augment the body's healing response. Microparticles provide a surface that can mimic the environment cells perceive in vivo, …


Cellulose And Sulfate Degradation In A Biochemical Reactor During Treatment Of Mine Drainage, Sweta Ojha Jan 2018

Cellulose And Sulfate Degradation In A Biochemical Reactor During Treatment Of Mine Drainage, Sweta Ojha

Masters Theses

"Seventy-two biochemical reactors were set up, and operated using a mixture of chip-bark, horse manure, and gravel as the biochemical treatment substrate. The simulated mine water containing sulfate (1000 mg/l) was pumped into each reactor at a flow rate of 0.5 ml/minute (approximate), giving an empty bed contact time of 8 days. The main idea is that the microorganisms present in horse manure would convert the cellulose in chip-bark into volatile fatty acids. The produced volatile fatty acid would enhance the metabolism of sulfate-reducing bacteria (SRB) initially present in horse manure, which would degrade (and eventually remove) the sulfate from …


Grain Refinement Of High Alloy Stainless Steels In Sand And Directionally Solidified Castings, Dustin Alan Arvola Jan 2018

Grain Refinement Of High Alloy Stainless Steels In Sand And Directionally Solidified Castings, Dustin Alan Arvola

Masters Theses

"The goal of this research project is to develop an industrially viable melting process that will control the crystallization macrostructure of austenitic grades of cast steels. Titanium nitride (TiN) has proven to be an effective grain refiner of austenite. Theoretical simulation and experimental application has led to the development of a repeatable grain refining melt process for austenitic stainless steel alloys.

Grain refinement of the as-cast structure of Cr-Ni stainless steel alloys solidified with primary FCC, BCC and dual FCC/BCC phases was studied experimentally. Refinement was achieved in both cast ferritic and austenitic grades. Dual solidification of …


A Network Tomography Approach For Traffic Monitoring In Smart Cities, Ruoxi Zhang Jan 2018

A Network Tomography Approach For Traffic Monitoring In Smart Cities, Ruoxi Zhang

Masters Theses

"Various urban planning and managing activities required by a Smart City are feasible because of traffic monitoring. As such, the thesis proposes a network tomography-based approach that can be applied to road networks to achieve a cost-efficient, flexible, and scalable monitor deployment. Due to the algebraic approach of network tomography, the selection of monitoring intersections can be solved through the use of matrices, with its rows representing paths between two intersections, and its columns representing links in the road network. Because the goal of the algorithm is to provide a cost-efficient, minimum error, and high coverage monitor set, this problem …


Research And Development Of Optically Transparent Join With Low Processing Temperatures, Eric Kevin Muskovin Jan 2018

Research And Development Of Optically Transparent Join With Low Processing Temperatures, Eric Kevin Muskovin

Masters Theses

The purpose of this study was to investigate durable solar cell cover glass joins produced by diffusion bonding with deep eutectic solvents (DES) and to develop a novel process of joining optically transparent materials at low temperatures. A joined PV cell-glass specimen was characterized using Raman, μ-FTIR, SEM-EDS, and thin-film XRD. DESs were created with malonic acid (MAL) and choline chloride (ChCl) of varying composition factors (CF; CF=MAL/ChCl). Joining borosilicate glass coupons was attempted using DESs with CF = 0.65 and 1 at temperatures between 100-150 °C for 20 hours. Joining the glass coupons failed at all temperatures and oxygen …


Customized Multi-Group Cross Section Generation With Njoy For Discrete Ordinates Computed Tomography And Radiography Simulation, Steven Michael Wagstaff Jan 2018

Customized Multi-Group Cross Section Generation With Njoy For Discrete Ordinates Computed Tomography And Radiography Simulation, Steven Michael Wagstaff

Masters Theses

"The purpose of this work was to explore the creation of photoatomic multi-group cross section libraries to be used with a software package DOCTORS (Discrete Ordinates Computed TOmography and Radiography Simulator). This software solves the linear Boltzmann equation using the discrete ordinates method [1]. To create these libraries, NJOY2016 was used, creating both fine and broad energy multi-group cross section files. The cross section's accuracy was tested against an equivalent Monte Carlo simulation using MCNP6.

Two simulation geometries were used. The first, a cylindrical water phantom with a single source projection placed in front, simulating an X-ray radiography. The second …


Designed Extrudate For Ceramic Additive Manufacturing, Devin Mcmillen Jan 2018

Designed Extrudate For Ceramic Additive Manufacturing, Devin Mcmillen

Masters Theses

"The objective of this thesis work was to design ceramic paste systems that assist in achieving a high theoretical density ( > 95%) after deposition by a novel additive manufacturing process, i.e. Ceramic On-Demand Extrusion (CODE). The work is encompassed in five main sections: Sections 1 and 2 provide an introduction and literature review of relevant topics for the following sections of experimentation. Section 3 provides an analysis of a reaction chemistry to identify three discrete materials that could be combined via CODE and result in zirconium diboride (ZrB2) post-sintering. Section 4 describes the development of a high solids …


The Development Of A New Formulation Of Fly Ash Class C Based Geopolymer And Assessing Its Performance In Presence Of Drilling Fluid Contamination, Mohamed Saad Ahdaya Jan 2018

The Development Of A New Formulation Of Fly Ash Class C Based Geopolymer And Assessing Its Performance In Presence Of Drilling Fluid Contamination, Mohamed Saad Ahdaya

Masters Theses

"Cementing is one of the most critical steps in the drilling and completion of oil wells. Traditionally, Portland cement is used for oil cementing operations; however, geopolymer materials have recently attracted much attention because they are more cost-effective and have less environmental impacts.

An intensive laboratory work was conducted to obtain a new formulation of fly ash class C based geopolymer cement to be used as a potential alternative cementing material to Portland cement in oil and gas cementing. Twenty-four variations of fly ash class C based geopolymers were prepared, and by comparing several of their properties using API standard …


Field Implementation Of Cement-Based Composite Strengthening Technologies, Michael Andrew Janke Jan 2018

Field Implementation Of Cement-Based Composite Strengthening Technologies, Michael Andrew Janke

Masters Theses

"With infrastructure continuing to age, technologies are being developed to strengthen structures as a more sustainable option than replacement. The use of fiber-reinforced cementitious matrix (FRCM) strengthening systems is a promising new technology for adding flexural and shear capacity to existing reinforced concrete members. While cement based systems with carbon, PBO, and steel have all been implemented in a lab setting, there is not research data available for installation in the field. FRCM composites have advantages over more widely used fiber reinforced polymer (FRP) composites such as heat resistance and compatibility with concrete substrate. FRP systems have previously been field …