Engineering Commons^™

Methods To Remotely Eliminate Biofilm From Medical Implants Using 2.4 Ghz Microwaves, Brett Glenn

Mechanical Engineering Undergraduate Honors Theses

Infections associated with biofilm growth are usually challenging to eradicate due to their high tolerance toward antibiotics [11, 12]. Biofilms often form on the inert surfaces of medically implanted devices [13]. No matter the sophistication, microbial infections can develop on all medical devices and tissue engineering constructs [12]. Related infections lead to 2 million cases annually in the U.S., costing the healthcare system over $5 billion in additional healthcare expenses [12].

Novel solutions to biofilm’s microbial colonization span the spectrum of engineering and science disciplines. Yet a practical solution still does not exist. The research presented here will explore a …

Modelling Palladium Decorated Graphene Using Density Functional Theory To Analyze Hydrogen Sensing Application, Sameer Kulkarni

Mechanical Engineering Undergraduate Honors Theses

Graphene is an exciting new material with many promising applications. One such application of graphene is gas sensing, when adsorbed with transition metals, notably Palladium. Therefore, it is of paramount importance to have appropriate ab initio calculations to calculate the various properties of graphene under different adsorbates and gasses. The first step in these calculations is to have a functioning base Density Functional Theory (DFT) model of pristine graphene decorated with Palladium. The computational methods described in this paper has yielded results for pristine graphene that have been confirmed many times in previous experimental and theoretical studies. Future work needs …

Bgaas Alloy Semiconductors For Lasers On Silicon, Joshua Mcarthur

Mechanical Engineering Undergraduate Honors Theses

In the world of semiconductors today, there is a large dissonance between optical devices and electrical application. Due to the limitations of electron transport, photonic integrated circuits are soon-to-be vital in fields like telecommunications and sensing. Right now, these PIC’s are mostly made from indium phosphide. Due to its ubiquitous nature, however, there is a huge push to integrate efficient optics with silicon. It’s cheap, abundant, dope-able, and our electronic infrastructure is based on it. The reason why silicon photonics aren’t already commercialized is because of silicon’s indirect bandgap—it is inefficient with optical applications. The problem with combining direct gap …

Left Atrial Model, Borna Sobati, Sarah Porello, Tess Pate

Biomedical Engineering

The objective is to produce an electrophysiological model of an adult human left atrium. This model will be used to test mapping probe catheters used for locating cardiac arrhythmias against current technology used in practice. Dr. Chris Porterfield requested this model and other physicians or probe catheter manufacturers may also use this product in the future. Dr. Porterfield also discussed the possibility of future senior project groups using the model as a bench test for designing new catheter tips. The model will precisely simulate electrical behaviors of the heart in normal as well as arrhythmic conditions. Ideally, the model will …

The Influence Of Heat Treatment On Corrosion Behavior Of Martensitic Stainless Steel Uns 42670, Armen Kvryan

Boise State University Theses and Dissertations

Ceaseless demand for lighter, faster, and more efficient aircraft has been one of the greatest driving forces behind bearing steel innovations. Recent studies demonstrate that corrosion is one of the leading causes of bearing failure in both military and commercial aircraft. High-performing bearing steels are available but are not being used in US military applications due to high cost and security issues when steels are produced outside of the continental United States. One approach to address this issue is to engineer steels that are cost-efficient and heat treated for corrosion resistance, long wear life, etc.

This dissertation presents information on …

Additive Manufacturing Of High Performance Flexible Thermoelectric Generators Using Nanoparticle Inks, Tony Valayil Varghese

Boise State University Theses and Dissertations

Flexible thermoelectric devices are attractive power sources for the growing demand of flexible electronics and sensors. Thermoelectric generators have an advantage due to no moving parts, silent operation and constant power production with a thermal gradient.

Conventional thermoelectric devices are rigid and fabricated using complex and relatively costly manufacturing processes, presenting a barrier to increase the market share of this technology. To overcome such barriers, this work focuses on developing near ambient-temperature flexible thermoelectric generators using relatively low-cost additive manufacturing processes. A screen printable ink was developed for transforming nanoparticle ink into high-performance flexible thermoelectric generators with a peak thermoelectric …

(111)-Oriented Gallium Arsenide Tensile-Strained Quantum Dots Tailored For Entangled Photon Emission, Christopher Schuck

Boise State University Theses and Dissertations

The use of molecular beam epitaxy (MBE) to create quantum dots (QDs) embedded in solid-state semiconductor media has been at the forefront of novel and record-breaking optoelectronic device development for many years. However, the wide range of semiconductor fabrication capabilities and the non-equilibrium growth parameters inherent to MBE mean that there are still many QD research frontiers that are yet to be explored.

This work focuses on a recently discovered method that permits, for the first time, the growth of QDs under tensile strain on non-(100) surfaces. My research explores the first (and currently only) optically active materials system for …

Structural Design Guidelines For Pervious Concrete Pavements, April Smith

Civil Engineering Undergraduate Honors Theses

Pervious pavements have gained popularity in recent years as the transportation industry focuses on sustainability and environmental impact. This research investigated the structural design of pervious concrete pavements. There is no standard design method; therefore, the goal was to lessen ambiguity surrounding the use of pervious concrete for pavement structures. By characterization of the rigid pavement design equation from the 1993 AASHTO Structural Design Guide for Design of Pavement Structures through laboratory exploration and review of existing literature, a guide was created to assist engineers in the design of pervious concrete pavements.

Improved Data Acquisition Using A Novel Dynamic Mechanical Analysis Sample Preparation Technique: The Numbers Do Not Lie, Jordan J. Winetrout

Honors Theses

Dynamic mechanical analysis (DMA) is a technique commonly used to identify the thermomechanical properties of polymeric materials. In the aerospace industry, a typical DMA sample is a glassy epoxy-amine polymer network. On a laboratory scale, these types of materials are cured in a silicon mold and sanded by hand to yield a sample with testable dimensions. This preparation technique is time consuming and causes sample imperfections which negatively affects data acquisition. This thesis aims to absolve the issues with DMA sample preparation by using a custom vacuum housing and a DeWALT^TM brand orbital sander. This novel approach has been …

Synthesis And Characterization Of Dielectric And Multiferroic Nanocrystalline Transition Metal Oxide Materials And Nanocomposites, Frederick A. Pearsall

Dissertations, Theses, and Capstone Projects

Nanocrystalline transition metal oxides with unique chemical, physical, magnetic and dielectric properties have very broad applications, ranging from photocatalysis, capacitor energy storage and 4-state memory. Frequency stable, high permittivity nanocomposite capacitors produced under mild processing conditions offer an attractive replacement to MLCCs derived from conventional ceramic firing. In one project reported herein, 0-3 nanocomposites were prepared using BaTiO₃ (barium titanate, BTO) nanocrystals, suspended in a poly(furfuryl alcohol) matrix, resulting in a stable, high effective permittivity, low and stable loss dielectric. Effective medium approximations were used to compare this with similar nanocomposite systems. The use of synthesized BTO nanocrystal photocatalysts …

Modeling And Experimental Determination Of Physical Properties Of Ge X Ga Y Se 1-X-Y Chalcogenide Glasses Ii: Optical And Thermal Properties, Jason Lonergan, Charmayne Lonergan, John Mccloy, Kathleen A. Richardson

Materials Science and Engineering Faculty Research & Creative Works

This study systematically analyzed the correlation between topological structure and chemical ordering on the optical and thermal properties of synthesized material in the glass forming region of the Ge_xGa_ySe_1-x-y ternary. A series of ten compositions from 5 to 30 mol% Ge and 5 to 15 mol% Ga were examined within the ternary, showing broadband infrared properties with transmission from 1 to 25 μm. Topological constraint theory applied to compositions examined exhibited sharp inflection at the average coordination number of = 2.67 defined as the chemical threshold where the glass network consists of tetrahedral Ge(Ga)Se_{2 …}

Mechanical Properties Of Heusler Alloys, Wesley Everhart, Joseph William Newkirk

Materials Science and Engineering Faculty Research & Creative Works

Heusler alloys have been a significant topic of research due to their unique electronic structure, which exhibits half-metallicity, and a wide variety of properties such as magneto-calorics, thermoelectrics, and magnetic shape memory effects. As the maturity of these materials grows and commercial applications become more near-term, the mechanical properties of these materials become an important factor to both their processing as well as their final use. Very few studies have experimentally investigated mechanical properties, but those that exist are reviewed within the context of their magnetic performance and application space with specific focus on elastic properties, hardness and strength, and …

Research Of Electro-Optical Effect In Metal Halide Perovskites By Fabry-Perot Interometer Method, Hanxiang Yin

McKelvey School of Engineering Graduate Student Theses & Dissertations

Perovskites have been investigated a lot by present and reported with outstanding optoelectronic properties. However, so far there is no publications about another important property, the electro-optical (EO) effect which is related to important applications in photolithography. This thesis is mainly mean to calculate the EO constants of one kind of organic perovskite material, CH₃NH₃PbI₃, which has been reported to have good capability of forming film by spin-coating, through the way of putting the film of CH₃NH₃PbI₃ between two layers of metal mirrors to build a Fabry-Perot interferometer and …

Nanoparticle Doped Optical Fibers For High Energy Lasers, Amber L. Vargas

All Theses

Fabrication of rare earth (RE) doped optical fibers for use in fiber-based lasers and amplifiers is conventionally performed using a solution doping technique where RE salts (i.e., ErCl3) are dissolved in a solvent, introduced into the porous silica soot, dried and consolidated to form the active fiber core. This process does not allow for tailoring of the chemical environment about the RE. Alternatively, nanoparticle (NP) doping is more recent approach to incorporating rare earths into an optical fiber and have been shown to permit modification of the chemical environment around the RE in ways the enhance spectroscopic performance. This is …

The Development Of A Viscoelastic Ellipsoidal Model For Use In Measuring Plantar Tissue Material Properties During Walking, Jessica Lee Deberardinis

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: The mechanical characteristics of the plantar tissues during walking is not well understood as most of the current research focuses on testing specific plantar regions in cadavers or while the feet of the participants are raised. In this work, it is hypothesized that a viscoelastic geometric ellipsoid model used to assess multiple structures of the foot would be accurate and robust. This model would be participant-specific and applicable to the entire stance phase of gait.

Methods: The proposed viscoelastic ellipsoid model would represent several key anatomical areas: Heel, Posterior Midfoot, Anterior Midfoot, Metatarsals 1-2, Metatarsals 3-5, Toe 1, Toe …

Equation Of State Of H2o Ice Using Melt-Recrystallization, Zachary Michael Grande

UNLV Theses, Dissertations, Professional Papers, and Capstones

The recent surge in exoplanet discoveries due to advancements in astrophysical technology and analysis has brought the reliability of early equation of state measurements into question as they are the limiting factor when modeling composition of these planets. H2O content is among the most important for the search of habitable planets as well as in understanding planetary dynamics and atmosphere formation. Over the last three decades the equation of state of H2O has been investigated with various techniques but, has suffered from anisotropic strain and poor powder statistics resulting in a large discrepancy in equation of state fits. At pressures …

Cesium Platinum Iodide Perovskite Synthesis, Development And Application In Photovoltaic Devices, Dakota Schwartz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Third generation photovoltaics, including perovskites, are essential to improving solar technology for widespread future use. Perovskite solar cells have surpassed 23.7% power conversion efficiency, comparable to traditional silicon photovoltaic panels. However, these perovskites are fabricated using lead-based compounds, posing toxicity issues. Furthermore, existing perovskites have limited thermal and moisture stability in ambient environments. In order to address toxicity and stability concerns, as well as to maximize photon absorption in solar cells through bandgap optimization, this effort focuses on the development of novel leadfree perovskite materials. A cesium platinum iodide composition is selected as a model system due to the theoretical …

A Silicon Germanium Cmos Linear Voltage Regulator For Wireless Agricultural Applications, Aminta Naidili Castillo Robles

Graduate Theses and Dissertations

This thesis presents the design, simulation and test results of a silicon germanium (SiGe) complementary metal-oxide-semiconductor (CMOS) linear regulator. The objective of the circuit is to power other analog devices regardless of the load current and input voltage changes. The application of this regulator is to be part of a project developing a miniaturized semiconductor platform that can be inserted into stems of crops in order to measure data inside the plant and then send it wirelessly to the user. The linear regulator was designed on a BiCMOS SiGe 0.13µm which is a GlobalFoundries process. It has been tested at …

Plasmonic Properties Of Nanoparticle And Two Dimensional Material Integrated Structure, Desalegn Tadesse Debu

Graduate Theses and Dissertations

Recently, various groups have demonstrated nano-scale engineering of nanostructures for optical to infrared wavelength plasmonic applications. Most fabrication technique processes, especially those using noble metals, requires an adhesion layer. Previously proposed theoretical work to support experimental measurement often neglect the effect of the adhesion layers. The first finding of this work focuses on the impact of the adhesion layer on nanoparticle plasmonic properties. Gold nanodisks with a titanium adhesion layer are investigated by calculating the scattering, absorption, and extinction cross-section with numerical simulations using a finite difference time domain (FDTD) method. I demonstrate that a gold nanodisk with an adhesive …

Investigation Of Critical Technologies Of Chemical Vapor Deposition For Advanced (Si)Gesn Materials, Joshua Matthew Grant

Graduate Theses and Dissertations

The development of new materials for efficient optoelectronic devices from Group IV elements is the heart of Group IV photonics. This has direct ties to modern technology as the foundation for the electronics industry is silicon. This has driven the development of silicon-based optoelectronics using these other Group IV materials as silicon is a poor optical material due to its indirect band gap when compared to the III-V semiconductors that are used by most of the optoelectronics industry. While efforts have been made to integrate III-V materials onto silicon substrates, the incompatibility with the complementary metal oxide semiconductor process has …

Optical Enhancement In Periodic Plasmonic Gratings For Sers And Metal-Semiconductor-Metal Photodetectors (Msm-Pds) Applications, Ahmad Aziz Darweesh

Graduate Theses and Dissertations

This dissertation is aimed to numerically study the effect of plasmonic grating electrodes on the efficiency of metal-semiconductor-metal photodetectors (MSM PDs) and the sensitivity of Surface Enhanced Raman Spectroscopy (SERS). This research can benefit many areas of nanoscience and optics, including plasmonic applications, such as, super lenses, nano-scale optical circuits, optical filters, surface plasmon enhanced photo-detectors solar cells, imaging sensors, charge-coupled devices (CCD), and optical-fiber communication systems. Several parameters, wire widths and thickness, gap space, taper angle, and the incident wavelength and angle, were investigated. The goal of this research is to utilize the plasmonic phenomenon by using plasmonic gratings …

In Situ/Operando Visualization Of Electrode Processes In Lithium-Sulfur Batteries: A Review, Shuang-Yan Lang, Xin-Cheng Hu, Rui Wen, Li-Jun Wan

Journal of Electrochemistry

Lithium-sulfur (Li-S) batteries have been regarded as one of the most promising candidates for the next-generation energy storage devices. Fundamental understanding of the structure and evolution processes at electrode-electrolyte interfaces is essential to the further development. In this review, we summarize recent advances in the interfacial observations by means of various in situ/operando visualization techniques, including scanning probe microscopy (SPM), electron microscopy (EM), X-ray microscopy (XRM) and optical microscopy (OM). The real-time investigation provides important evidence for the morphology and component changes including S/Li₂S transformation, polysulfide dissolution on cathodes and Li/solid electrolyte interphase (SEI) evolution on anodes, which …

Recent Progress Of Electrochemiluminescence Sensors Based On Electrically Heated Electrode, Hui-Fang Zhang, Yi-Ting Chen, Fang Luo, Zhen-Yu Lin, Guo-Nan Chen

Journal of Electrochemistry

Electrochemiluminescence (ECL) has broad application in the fields of environmental monitoring and biological analysis due to its intrinsic advantages such as excellent versatility, good detection sensitivity, and high specificity. The intensity of ECL can be influenced by temperature variation in the ECL quantum efficiency and the rate of electrochemical reaction. However, traditional temperature control is commonly realized through bulk solutions heating, which is complicated and unfavorable for detection when the volatile and thermally unstable materials existed. In order to address these problems, electrically heated electrodes are used to adjust the temperature desired. The major character of this technique lies in …

Sensitive Photoelectrochemical Assay Of Nucleic Acids Based On Catalytic Hairpin Assembly And Ru(Nh3)63+, Ya-Min Fu, Xiao-Xia Yan, Xiao-Hua Zhang, Jin-Hua Chen

Journal of Electrochemistry

A simple “signal-on” photoelectrochemical (PEC) sensing platform for sensitive assay of nucleic acids was developed by coupling catalytic hairpin assembly (CHA) signal amplification strategy with Ru(NH₃)₆³⁺. Herein, cadmium sulfide (CdS) was deposited on the TiO₂/indium tin oxide (ITO) electrode by a method of successive ionic layer adsorption and reaction (SILAR), serving as one kind of photoelectric material to broaden absorption range of TiO₂ and to improve the photoelectric conversion efficiency. Thereafter, the capture DNA (C-DNA) was immobilized on the CdS/TiO₂/ITO electrode. Simultaneously, Au-hairpin DNA probe 1 (Au-HP1) and hairpin DNA …

A Facile Strategy For Two-Step Fabrication Of Gold Nanoelectrode For In Vivo Dopamine Detection, Li-Hao Guan, Chao Wang, Wang Zhang, Yu-Lu Cai, Kai Li, Yu-Qing Lin

Journal of Electrochemistry

In vivo monitoring neurochemicals with microelectrode is invasive and the damage to brain tissue may inevitably cause disturbance signals physiologically to the measurement. It is of great importance to reduce the electrode size and to decrease the damage. This study demonstrates a novel nanoelectrode preparation methodology for in vivo monitoring dopamine (DA) fluctuation in the living brain of rats with high dependability. The fabrication process of the gold nanoelectrode involving a few minutes consists of only two steps: 1) growing gold nanoseeds on surface of tip of glassy capillary by ion sputtering; 2) wet depositing a continuous conductive gold film …

Preparation And Electrocatalytic Oxygen Reduction Performance Of Self-Doped Sludge-Derived Carbon, Ya-Li Ye, Wei-Ming Feng, Ge Li, Zhen-Chao Lei, Chun-Hua Feng

Journal of Electrochemistry

The development of low-cost, high-performance cathode catalysts is critical for practical application of fuel cells. Here, the N, P-doped porous graphene-like carbon with outstanding oxygen reduction reaction (ORR) performance was synthesized by pyrolysis of surplus sludge, which functioned as a self-doped, self-activated, and self-templated precursor by acclimation with continuous feedings of phenol. The results show that the amounts of microorganisms were enriched after acclimation, with increasing contents of N, P, Fe, as well as C atoms. The increasing pyrolysis temperature resulted in the formation of an ordered graphitic structure, however, the excessively high temperature induced the drop in the amounts …

Graphene-Like Secondary-Laser-Etched Polyimide Film Decorated With CuXO Nanocomposites: A Novel Electrode Substrate For Non-Enzymatic Glucose Sensors, Wan-Lin Dai, Zhi-Wei Lu, Jian-Shan Ye

Journal of Electrochemistry

In this work, a novel electrode substrate with graphene-like surface and Cu_xO nanocomposites derived from secondary-laser-etched polyimide (SLEPI) film was synthesized and applied in non-enzymatic glucose detection for the first time. Characterizations indicate that the as-prepared SLEPI/Cu_xO film electrode (SLEPI/Cu_xO-FE) possessed huge surface area, plentiful active sites and excellent electrocatalytic performance. The obtained sensor exhibited the high sensitivity and selectivity for glucose determination with a linear range of 0.05 mmol·L^-1 to 3 mmol·L^-1 and a detection limit of 1.72 μmol·L^-1 (S/N=3), which provides a simple, flexible and low-cost electrochemical sensor for …

Preparation And Capacitive Property Of Two-Dimensional Multilayer Ti3C2TX-Mxene/Ppy-Nw Composite Material, Lu Chen, Xuan Jian, Min He, Mi-Mi Zhang, Xiao-Die Chen, Lou-Jun Gao, Zhen-Hai Liang

Journal of Electrochemistry

In this paper, the two-dimensional multilayered Ti₃C₂T_x-MXene was obtained by hydrofluoric acid etching method on the bulk phase material MAX(Ti₃AlC₂) substrate. The two-dimensional multilayered Ti₃C₂T_x-MXene/PPy-NW composite electrode materials were successfully prepared by combining the one-dimensional polypyrrole nanowires (PPy-NW) with two-dimensional multilayered Ti₃C₂T_x-MXene. The morphologies and compositions of the synthetic materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Electrochemical tests showed that Ti₃C_{2 …}

Preliminary Automated Determination Of Edibility Of Alternative Foods: Non-Targeted Screening For Toxins In Red Maple Leaf Concentrate, Joshua M. Pearce, Maryam Khaksari, David C. Denkenberger

Michigan Tech Publications, Part 1

Alternative food supplies could maintain humanity despite sun-blocking global catastrophic risks (GCRs) that eliminate conventional agriculture. A promising alternative food is making leaf concentrate. However, the edibility of tree leaves is largely uncertain. To overcome this challenge, this study provides the methods for obtaining rapid toxics screening of common leaf concentrates. The investigation begins with a non-targeted approach using an ultra-high-resolution hybrid ion trap orbitrap mass spectrometer with electrospray ionization (ESI) coupled to an ultra-high pressure two-dimensional liquid chromatograph system on the most common North American leaf: the red maple. Identified chemicals from this non-targeted approach are then cross-referenced with …

A New Pedot Synthesis Method And Its Application In Energy Storage, Haozhe Chen

McKelvey School of Engineering Graduate Student Theses & Dissertations

Conducting polymer is a common electrode material in supercapacitors, people usually create nano-structure on electrode surface to enhance the performance of supercapacitors. Synthetic nanostructured polymers have been implemented in many ways, most of them are template-based synthesis, which is time consuming and expensive, people are pursuing an easier way to synthesize nanostructured conducting polymers. Combining ferric chloride solution hydrolysis and EDOT polymerization to get PEDOT nano fiber in one step has been achieved. We develop a new method to synthesis PEDOT nano fiber from solid-state iron in one step. Our process takes place in a single step inside a sealed …