Engineering Commons^™

Electrocoagulation For Sulfate Removal, Hailey Marie Dunsworth

Chemical Engineering Undergraduate Honors Theses

In the United States, one of the major rising issues is water shortage, especially in Western, inland states with arid climates. Not only do deficiencies exist for potable water, but for irrigation and agricultural purposes as well. Currently, the Brackish Groundwater National Desalination Research Facility in Alamogordo, New Mexico has four separate wells that are being used for experimentation. A major concern is that a considerable amount of this water can be used as another reliable source for potable water if treated. The WERC-A-HOLICS have identified two possible methods to alleviate this problem. Electrocoagulation (EC) is a technology useful for …

Radiative Cooling To The Night Sky, Alexander R. Enderlin

Chemical Engineering Undergraduate Honors Theses

Silicon wafer fabrication facilities require a significant amount of temperate cooling water to meet high internal cooling loads. The tertiary chilled water systems operate year round to fulfil the constant cooling load needed for production. Conventional chillers require a large amount of electricity to cool the water by the vapor compression cycle. As energy costs increase and environmental stewardship becomes the norm in industry, sustainable technologies are needed to chill process cooling water without the significant energy consumption of today’s chillers. Night sky radiation cools a medium by radiating heat from a warm medium to the colder night sky. The …

Electrocoagulation For Sulfate Removal, Gina Marie Densmore

Chemical Engineering Undergraduate Honors Theses

In the United States, one of the major rising issues is water shortage, especially in Western, inland states with arid climates. Not only do deficiencies exist for potable water, but for irrigation and agricultural purposes as well. Currently, the Brackish Groundwater National Desalination Research Facility in Alamogordo, New Mexico has four separate wells that are being used for experimentation. A major concern is that a considerable amount of this water is currently wasted by being sent to evaporation ponds without any sort of treatment for human consumption. The WERC-A-HOLICS have identified two possible methods to alleviate this problem. Electrocoagulation (EC) …

Impregnation And Adsorption Of Rare Earth Elements On Amberlite Xad-7, Bobby G. Hampton

Chemical Engineering Undergraduate Honors Theses

Beads were washed then impregnated with an organophosphorous extractant D2EHPA. The washing process, as well as factors in the impregnation process were studied. Water was deemed sufficient to prewash the beads before use over small and large amounts of acid with acetone. The impregnation of beads at an Amberlite D2EHPA ratio of 1:1 was determined to be best. Absorption isotherms of Neodymium were the first to be studied. By testing different concentrations, Amberlite was determined to absorb the max amount at 4000 ppm. The pH values from 2-7 were determined to have no effect on the amount of Neodymium absorbed …

Ultrasonic Hoguanauts Werc Task 2: Separation Of Oil From Water, Jesus Eduardo Martinez

Chemical Engineering Undergraduate Honors Theses

Engineering, Chemical Engineering, Environmental

Use Of Peptoid Microspheres To Improve Enzyme Linked Immunosorbent Assay (Elisa) Microarray For Early Cancer Detection, Valerie Del Carmen Reyez Loayza

Chemical Engineering Undergraduate Honors Theses

The pursuit of an efficient and economical technique for early detection of cancer has led to the development of sophisticated biosensors for antigen analysis. As biosensors become more complex, coatings are necessary and important. The preferred coatings need to have the following properties: high surface area for binding, resistance to biofouling, and flexible synthesis. The focus of this project is to determine whether using peptoid microsphere-coated glass slides in the enzyme linked immunosorbent assay (ELISA) microarray technique is better than using commercially available glass slides. Current microarray slides are coated with reactive groups, such as amines, epoxides, or aldehydes. It …

Separatome Of Escherichia Coli Analysis Of Deae Chromatography As Ph Of Loading Changes, Rita E. Tejada Vaprio

Chemical Engineering Undergraduate Honors Theses

Recombinant DNA technology is used to produce therapeutics in host organisms and undergoes several purification steps before it can be used by the end user. Escherichia coli which has been widely studied has been the microorganism of choice mainly because of its low production costs. The primary objective of this study was to investigate the optimal conditions to purify a protein of interest with antifungal properties. Varying the loading pH alters the overall charge of both the target protein and host cell proteins (HCPs). Identifying genomic proteins that remain bound regardless of loading pH on DEAE columns will guide future …

Enhancement Of The Performance Of Gaas Based Solar Cells By Using Plasmonic, Anti-Reflection Coating And Hydrophobic Effects, Yahia Fayiz Makableh

Graduate Theses and Dissertations

Investigation of renewable energy resources is gaining huge momentum in recent years due to the limited fossil fuels, and their detriment impact on the environment. Solar energy is promising to meet the increased energy demand. In order to achieve this goal, solar energy has to be harvested efficiently at low cost. Therefore, higher efficiency solar cells are the primary focus of research worldwide. Photovoltaics based on InAs/GaAs intermediate band solar cells and their device performance enhancements are investigated in this dissertation. The device enhancement is carried out by surface modification methods. The dissertation work is inspired by the need of …

Design And Verification Environment For High-Performance Video-Based Embedded Systems, Michael Mefenza Nentedem

Graduate Theses and Dissertations

In this dissertation, a method and a tool to enable design and verification of computation demanding embedded vision-based systems is presented. Starting with an executable specification in OpenCV, we provide subsequent refinements and verification down to a system-on-chip prototype into an FPGA-Based smart camera. At each level of abstraction, properties of image processing applications are used along with structure composition to provide a generic architecture that can be automatically verified and mapped to the lower abstraction level. The result is a framework that encapsulates the computer vision library OpenCV at the highest level, integrates Accelera's System-C/TLM with UVM and QEMU-OS …

Data Integrity Verification In Cloud Computing, Katanosh Morovat

Graduate Theses and Dissertations

Cloud computing is an architecture model which provides computing and storage capacity as a service over the internet. Cloud computing should provide secure services for users and owners of data as well. Cloud computing services are a completely internet-based technology where data are stored and maintained in the data center of a cloud provider. Lack of appropriate control over the data might incur several security issues. As a result, some data stored in the cloud must be protected at all times. These types of data are called sensitive data. Sensitive data is defined as data that must be protected against …

Top-Down Aluminum Induced Crystallization For Photovoltaics, Seth Daniel Shumate

Graduate Theses and Dissertations

Passivating silicon solar cell surfaces is critical to fabricating very high efficiency and low cost photovoltaic devices. The sun-facing surface of the solar cell, known as the emitter, is particularly important when designing a solar cell. This work focused first on an alternative method of forming the emitter of silicon solar cells, and secondly on a method for improving the surface passivation of both these non-traditional and standard n-type solar cells.

Top-down aluminum induced crystallization (TAIC) was used for forming a polycrystalline silicon layer from amorphous silicon using aluminum to catalyze the crystallization at much lower temperatures than otherwise possible. …

Large-Scale Graphene Film Deposition For Monolithic Device Fabrication, Khaled Al-Shurman

Graduate Theses and Dissertations

Since 1958, the concept of integrated circuit (IC) has achieved great technological developments and helped in shrinking electronic devices. Nowadays, an IC consists of more than a million of compacted transistors.

The majority of current ICs use silicon as a semiconductor material. According to Moore's law, the number of transistors built-in on a microchip can be double every two years. However, silicon device manufacturing reaches its physical limits. To explain, there is a new trend to shrinking circuitry to seven nanometers where a lot of unknown quantum effects such as tunneling effect can not be controlled. Hence, there is an …

Epitaxial Growth Of Silicon On Poly-Crystalline Si Seed Layer At Low Temperature By Using Hot Wire Chemical Vapor Deposition, Manal Abdullah Aldawsari

Graduate Theses and Dissertations

There has been a growing interest in using low cost material as a substrate for the large grained polycrystalline silicon photovoltaic devices. The main property of those devices is the potential of obtaining high efficiency similar to crystalline Si devices efficiency yet at much lower cost because of the thin film techniques. Epitaxial growth of Si at low temperatures on low cost large grained seed layers, prepared by aluminum induced crystallization method (AIC), using hot wire chemical vapor deposition (HWCVD) system is investigated in this thesis. In this work, different parameters have been studied in order to optimize the growth …

Economic Impact Of The Reflectivity Of Roofs, Adam Osmon

Mechanical Engineering Undergraduate Honors Theses

For years, dark roofs have been used on residential and commercial buildings in all areas of the United States, but these roofs absorb large amounts of solar radiation, which can result in high cooling costs for the building. In some parts of the country, using a cool roof on a building is more beneficial because it will lower the energy consumption (and therefore will reduce energy costs) of heating and cooling the building. This paper summarizes the results from using the program eQUEST to analyze three different types of buildings – an office, a high school, and a hospital – …

Phase Field Modeling And Simulation Of Dendritic Growth With Varying Latent Heat And Seeding Distributions, Jordan W. Key

Mechanical Engineering Undergraduate Honors Theses

In order to simulate microstructure evolution during a solidification process, the Kobayashi model was studied and a MATLAB code was developed and implemented. Solidification simulations were performed with varying latent heat values and with different initial seeding distributions.

Comparison Of Evaluation, Measurement & Verification Processes: Arkansas To Bordering States, William Burgess Carlisle

Mechanical Engineering Undergraduate Honors Theses

The purpose of this paper is to compare Evaluation, Measurement, and Verification (EM&V) standards established by Arkansas and surrounding states. EM&V is the process to quantify the energy savings of an energy management project. This paper details the rules and regulation regarding the EM&V proceedings required by investor-owned utilities in providing energy-saving projects. By comparison of each state’s requirement, a clear understanding is found on where Arkansas stands in maturity of its program requirements. The reader will find Arkansas on the forefront of EM&V standardization that represents a model that surrounding states are striving to emulate.

Interface Property Of Collagen And Hydroxyapatite In Bone, Clint D. Paul

Mechanical Engineering Undergraduate Honors Theses

When looking at bone at the nanoscale, it consists of a matrix of type I collagen and hydroxyapatite (HAP). Type I collagen is the most abundant protein in the body and together with the mineral HAP [Ca10(PO4)6(OH)2] is responsible for most of the structural integrity of bone. Collagen fibrils in bone contain HAP platelets of varying size dispersed between the collagen. The composition of the type I collagen is predicted to play a role in the mechanical properties of the interface. Our research looks at healthy heterotrimeric collagen and mutated homotrimeric collagen containing three identical chains. Both types of collagen …

Gui Matlab Code To Display Damped, Undamped, Forced And Unforced Mass Spring Systems, Melanie Garcia

Mechanical Engineering Undergraduate Honors Theses

Machine Dynamics and Control is the course offered at the University of Arkansas that deals with damped, undamped, forced and unforced systems. It’s important for students to understand each of these systems for future implementation in the industry and daily real life situations. The three types of damped systems, underdamped, overdamped and critically damped are analyzed in this thesis. As well as only two of the most common forced functions are analyzed, the cosine and sine functions. The objective of this thesis was to develop a GUI code in Matlab that would help students visualize the differences between undamped, damped, …

Semi-Automated Switching Regulator Modeling Method And Tool, Michael Heath Leonard

Graduate Theses and Dissertations

This thesis presents the results of research targeted at automating the behavioral modeling process for switching voltage regulators. These regulators are commonly used in many application areas including discrete use in larger systems, integrated in a System on a Chip (SoC), or as the primary use case for a design. When used in an integrated system these regulators can be a significant force in slowing down simulations. A common method for removing this slowdown is to use a behavioral model of the switching regulator.

Creating behavioral models can be very time consuming and requires expertise.

The thesis discussion begins by …

Drive Plate Mass Polar Moment Of Inertia In Stokeo Type Resonant Column Devices, Michael Ryan Deschenes

Civil Engineering Undergraduate Honors Theses

The calibration procedure employed by researchers at the University of Arkansas (UA) to calibrate two Stokoe-type resonant column torsional shear (RCTS) devices is presented herein. Specifically, the development of a device-specific calibration process to determine the mass polar moment of inertia of the RCTS drive plate assemblies (J0), as a function of frequency, is described. Three aluminum calibration specimens and three stainless steel masses with known geometric and material properties were utilized to experimentally determine the J0 values. Experimental data collected by researchers at the University of Arkansas and obtained from other sources (Utah State University, the University of Texas …

Alkali-Silica Reaction Mitigation Using High Volume Class C Fly Ash, Sydney Marie Dickson

Civil Engineering Undergraduate Honors Theses

Fly ash is the residue produced from coal combustion in electric generating plants. There are two types of fly ash, Class C and Class F. Approximately 40 percent of fly ash generated from coal combustion can be used as a partial replacement of cement in concrete. Incorporating fly ash improves concrete properties and extends its service life. Alkali-silica reaction (ASR) is an expansive reaction between reactive silica typically found in aggregates (rock and sand) and alkalis in cement. This reaction results in the formation of a gel that absorbs water and swells, which exerts an internal pressure in concrete. This …

Analyzing Stochastically Generated Material Properties For The Use In Mumerical Simulations Of Advanced Laboratory Tests Of Asphalt Concrete, Ken K. Rutabana

Civil Engineering Undergraduate Honors Theses

For such a large country as the US, adequate road transportation is a vital necessity that ensures the safety, prosperity, and development of the people. Covering 94% of the two million miles of paved roads and highways, asphalt concrete is essential to this country. This is one reason why it is crucial to understand the potential and limitations of asphalt concrete. Unfortunately, material testing is a costly and time consuming ordeal. Consequently, numerical modeling of asphalt testing using computer software has been successfully developed in the last decades. These models corroborate those obtained in the lab but are intended as …

Development Of Optimal Experimental Design Parameters For Pseudo Ambient Vibration Testing Of Bridges, David Samudio Castillo

Civil Engineering Undergraduate Honors Theses

The United States of America is facing an infrastructure crisis that is characterized by aging and deteriorating structures, a significant backlog of maintenance and upgrades for existing infrastructure, limited funding and lack of practical and effective tools for identifying and prioritizing the most pressing infrastructure needs. The American Association of Civil Engineers (ASCE) qualifies America’s infrastructure with a D+(ASCE Report Card). This rating reflects the general state of infrastructure that is unlikely to improve dramatically in the short-term, yet the situation costs the nation billions of dollars annually due to losses in economic efficiency and productivity, and in some cases …

The Production Of Biobutanol From Biomass Via A Hybrid Biological/Chemical Process, Thomas Melvin Potts

Graduate Theses and Dissertations

Biobutanol use as a fuel began in the late 19th century. Problems remain in economic viability. A review of the state of the art and need for technical advances is presented.

The technical potential of producing biofuel from a naturally occurring macroalgae was studied. The algae grow in Jamaica Bay, New York City, in contaminated water. The process consisted of mechanical harvesting, drying, grinding, and acid hydrolysis to form an algal sugar solution. Clostridium beijerinckii and C. saccharoperbutylacetonicum were used in an acetone butanol ethanol (ABE) fermentation to make butanol. Fermentation was followed by distillation Butanol concentrations during fermentation reached …

Novel Separation Methods Using Electrodialysis/Electrodeionization For Product Recovery And Power Generation, Alexander Miguel Lopez-Rosa

Graduate Theses and Dissertations

The use of electrodialytic separations for the purification of products has been a vital technique for the past 50 years in the chemical industry. Originally used for demineralization and desalination, electrodialysis and its counterparts have expanded to assist in product purification, waste and hazard removal, and power generation. This research focused on the development of high purity organic acids purification with low power requirements. Work resulted in the development of a new type of electrodialysis process, specifically the use of ionic liquids as a secondary solvent for the development of dual solvent electrodialysis. Through dual solvent electrodialysis, ions were recovered …

Inventory Management And Control "For A Cause", John Michael Miller

Graduate Theses and Dissertations

Companies today are changing the culture of business and beginning to involve more than just labor and money in overall decisions. Just as sustainability issues and humanitarian logistics are gaining popularity, so is the idea of using business to make a difference on society in addition to making a profit. As companies position themselves across the globe to make an impact, they employ people in third-world environments that create uncertainties on both the supply and demand sides. Also, the idea of strategically planning work with the goal of minimizing costs has been replaced by companies wanting to give more work …

Experimental Verification And Integration Of A Next Generation Smart Power Management System, Tavis Clemmer

Graduate Theses and Dissertations

With the increase in energy demand by the residential community in this country and the diminishing fossil fuel resources being used for electric energy production there is a need for a system to efficiently manage power within a residence. The Smart Green Power Node (SGPN) is a next generation energy management system that automates on-site energy production, storage, consumption, and grid usage to yield the most savings for both the utility and the consumer. Such a system automatically manages on-site distributed generation sources such as a PhotoVoltaic (PV) input and battery storage to curtail grid energy usage when the price …

Incorporating Environmental And Social Factors Into Decision-Making Of An Oil And Gas Industry To Improve Sustainability, Gaurav Dabhadkar

Graduate Theses and Dissertations

The energy industry (including the oil and gas industry) is facing unparalleled scrutiny and demands from stakeholders including investors, regulators (industry and environmental), communities, and other stakeholders. Sustainable development is one of the major concerns of the oil and gas industry. Companies are seeking to increase sustainability of their operations by considering environmental and Social concerns in addition to economic concerns. Oil and gas companies need to take decisions at different stages of the product life cycle (e.g. planning, design, exploration, production, and clean-up) which have direct or indirect impact on the organization's objectives. Addressing economic, technical, Social, and environmental …

Using The Triple Bottom Line To Select Sustainable Suppliers For A Major Oil And Gas Company, Pandarinath Adarsh Sunkari

Graduate Theses and Dissertations

Companies have primarily been focusing on the financial bottom line i.e., on increasing profits by increasing revenues and reducing costs. With high energy usage and environmental change posing threats to the environment and business operations, companies are now considering sustainability. Since some global suppliers have low cost labor, Social well-being and human development has also emerged as major goals of a company performing global operations. Focusing on these three goals is termed the "Triple Bottom Line" (TBL). We study and explore the TBL benefits that could be realized by an oil and gas company by focusing on sustainable suppliers. A …

Environmental Reliability Of Thin Film Sealing On Thick Film Ltcc, Charles R. Bourland

Graduate Theses and Dissertations

As electronic components and systems become more intricate and expand into new realms of use case scenarios, new materials systems must be explored. With new systems comes the balancing acts of cost and reliability. Presented here is a thesis that explores a new hybrid-electronics packaging system using low temperature co-fired ceramics, referred to as LTCC. An LTCC system was designed to explore the environmental reliability of numerous thick film LTCC features and parameters. A key element was to explore how a thin film metallization stack up used to cap or seal underlying thick film structures would decrease environmental susceptibility while …