Engineering Commons^™

Thin 3d Multiplication Regions In Plasmonically Enhanced Nanopillar Avalanche Detectors, Pradeep Senanayake, Chung-Hong Hung, Alan C. Farrell, David A. Ramirez, Joshua Shapiro, Chi-Kang Li, Yuh-Renn Wu, Majeed M. Hayat, Diana L. Huffaker

Electrical and Computer Engineering Faculty Research and Publications

We demonstrate a nanopillar (NP) device structure for implementing plasmonically enhanced avalanche photodetector arrays with thin avalanche volumes (∼ 310 nm × 150 nm × 150 nm). A localized 3D electric field due to a core–shell PN junction in a NP acts as a multiplication region, while efficient light absorption takes place via surface plasmon polariton Bloch wave (SPP-BW) modes due to a self-aligned metal nanohole lattice. Avalanche gains of ∼216 at 730 nm at −12 V are obtained. We show through capacitance–voltage characterization, temperature-dependent breakdown measurements, and detailed device modeling that the avalanche region is on the order of …

Kinetics And Mechanisms Of Titanium Wire Oxidation, Tanmay P. Engineer

Boise State University Theses and Dissertations

The kinetics and mechanisms of oxidation of titanium wire were assessed using a large test matrix in Ar-20% O₂ at 800 to 1200°C, and N₂-20% O₂ at 1000°C, for 0.5 to 24 hours. The effects of geometry on oxidation were evaluated by investigating the behavior of six high purity Ti wires with diameters varying from 50 to 2000 μm, with an objective of producing hollow TiO₂ tubes.

Oxidation behavior was characterized by measuring oxide thicknesses and morphology by optical microscopy, and the phases were characterized using a combination of SEM and TEM. The kinetics was …

Structural And Electronic Properties Of Cs-Doped Sic: A First-Principles Investigation, Tram Bui

Boise State University Theses and Dissertations

The structural and electronic properties of pure and Cs-doped cubic zinc-blende silicon carbide (3C-SiC) were modeled by density functional theory in the plane-wave pseudo-potential formalism as implemented in the Quantum-ESPRESSO package. The equilibrium properties including lattice constant, bulk modulus, cohesive energy, and the indirect band gap energy were calculated for pure 3C-SiC. These values were compared with the experimental and theoretical values reported in the literature, and there was generally excellent agreement.

The influence of Cs on SiC in two structural configurations were modeled, including bulk SiC and a Σ3 grain boundary. The present investigation mainly focused on the neutral …

Testing, Analysis, And Model Verification Of Miniature Linear Permanent Magnet Generators, Michael Ray Rippee

Boise State University Theses and Dissertations

The military has become increasingly dependent on mobile electronic equipment to ensure success and safety of soldiers in remote locations. To operate the electronics, soldiers must carry batteries that can weigh up to 12kg (26.5lb). To decrease the load soldiers must carry, a backpack with an internal linear electric generator has been proposed to provide portable power for soldiers on foot. In designing a generator for this purpose, a simulation was developed to predict the power generation capacity of linear permanent magnet generators. This thesis presents work done to experimentally verify the theoretical simulation with a desired accuracy of 20%. …

Extending The Battery-Powered Operating Time Of A Wireless Environmental Monitoring System, Ross Matthew Butler

Boise State University Theses and Dissertations

Advances in low-power microelectronics and sensor technologies have enabled the creation of sophisticated environmental monitoring systems capable of operating on battery power. Independence from a power outlet connection opens up many new potential applications, but limited battery life still imposes significant restrictions on a monitoring system’s capabilities and the number of systems that can be economically deployed and maintained. These restrictions have motivated much research into reducing monitoring system energy usage, increasing battery capacity, and harnessing alternative energy sources. While most of the research focuses on new system design, there is a need for techniques to extend the battery-powered operating …

Production Of Poly-?-Glutamic Acid By Bacillus Licheniformis: Synthesis And Characterization, N. Konglom, C. Chuensangjun, C. Pechyen, S. Sirisansaneeyakul

Journal of Metals, Materials and Minerals

Poly-?-glutamic acid (?-PGA), one type of amino acid polymers, consists of D-and L-glutamic acids linked with amide bonding between ?-amino and ?-carboxylic acids. Naturally, ?-PGA could be biodegradable polymer and water-solubleapplied in various industries such as food, cosmetics, and pharmaceutical industries. Variation of initial L-glutamic acid concentration affecting on the production of ?-PGA by fermentation of Bacillus licheniformis was studied. The batch fermentation process consists of preparing the inoculum and expanding the culture of B. licheniformis into E medium (pH 6.5) for ?-PGA production. ?-PGA was recovered by using methanol precipitation together with lyophilization. For characterization, the molecular size of …

Cetirizine Dihydrochloride Tablets Comprising Two Different Lubricants With Highly Loaded Colloidal Silicon Dioxide, P. Katewongsa, T. Phaechamud

Journal of Metals, Materials and Minerals

Recently, the fast disintegrating tablet (FDT) has started gaining popularity and acceptance as new drug delivery system. Cetirizine dihydrochloride (CD) is the selective histamine (H-1)-receptor antagonist that is demonstrated to treat the symptoms associated with seasonal and perennial allergic rhinitis which this drug nowadays was prepared in form of FDT. Lubricant typically influences on tablet disintegration time (DT) and wetting time (WT). Therefore, it is important for optimizing the lubricant amount in this dosage form. The purpose of this study was to evaluate the effect of the lubricants (magnesium stearate (Mg-st) and sodium stearyl fumarate (SSF)) on the CD tablet …

Influence Of Casting Techniques On Hardness, Tarnish Behavior And Microstructure Of Ag-Cu-Zn-Si Sterling Silver Jewelry Alloys, C. Chanmuang, W. Kongmuang, J.T.H. Pearce, T. Chairuangsri

Journal of Metals, Materials and Minerals

The effects of Zn and Si on the hardness, tarnish resistance and microstructures of experimental Ag-Cu-Zn-Si alloy were investigated by means of vickers hardness, tarnish testing, optical and scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The various compositions of 935 sterling silver alloys produced by different casting techniques, investment (lost wax) process and metal mould casting, were compared. An induction casting machine with a vacuum system was used for investment casting at 1,025C with the mould temperature at 600C whereas a LPG/oxygen single flame tip torch was used for the metal mould process. Vickers hardness of the samples …

Ballistic Performance Of Ceramic/S2-Glass Composite Armor, K. Dateraksa, K. Sujirote, R. Mccuiston, D. Atong

Journal of Metals, Materials and Minerals

Ceramic composite armor was initially developed during the Vietnam War for use as helicopter armor and personnel armor. The requirements for the armor were light weight and the capability to defeat small caliber armor piercing (AP) projectiles. Several different ceramics were developed and tested for this application. It was found that aluminum oxide (Al2O3), silicon carbide (SiC) and boron carbide (B4C) had the best combination of properties to meet the requirements. The long term goal of this research is to develop domestic knowledge, design and production capability of ceramic composite armors. In this present research, the relationship between the ballistic …

Bismuth Vanadate (Bivo4) Powder Prepared By The Sol-Gel Method, P. Pookmanee, S. Kojinok, S. Phanichphant

Journal of Metals, Materials and Minerals

Bismuth vanadate (BiVO4) powder was prepared by the sol-gel method. Bismuth nitrate and ammonium vanadate were used as the starting precursors with mole ratio of 1:1 in ethanol at 70C for 1 hour. The obtained sol was changed to the yellow gel after addition of deionized water and acetic acid. The yellow gel was dried at 100C for 48 h and calcined at 400-600C for 2 hours. The phase of BiVO4 powder was studied by X-ray diffraction (XRD). The morphology of BiVO4 powder was investigated by scanning electron microscopy (SEM). The element composition of BiVO4 powder was indicated by energy …

Effect Of Milling Method On The Particle Size Of Calcined 0.65pmn-0.35pt Powder, A. Boonruang, P. Ngernchuklin, C. Eamchotchawalit

Journal of Metals, Materials and Minerals

In this study, stoichiometric 0.65PMN-0.35PT powders have been prepared by columbite method. The perovskite single phase of PMN-PT was successfully synthesized after calcination of the mixed oxide at 900C/4hr. Due to the particle size of calcined powder has greatly effect on the electrical properties of sintered samples. Therefore, two different milling methods including high energy ball milling (HBM) and conventional ball milling (CBM) were used to grind the calcined powders. The results showed that the particle size distribution of calcined powders from HBM and CBM were 0.17 and 0.19 ?m, respectively. As a result, the relative density of the sintered …

Effect Of Zn Addition On Sol-Gel Derived Apatite/Wollastonite Glass-Ceramics Scaffolds, S. Tubsungneon Rattanachan, N. Srakaew, R. Pethnin, N. Suppakarn

Journal of Metals, Materials and Minerals

Bioactive glasses and glass-ceramics consisting of CaO-MgO-P2O5-SiO2 system have been shown to be bioactive, resorbable and to exhibit appropriate mechanical properties for bone tissue engineering applications. Bioactive glass-ceramics scaffolds consisting of zinc doped-apatite/wollastonite (AW) glassceramics were prepared by coating polyurethane foams with sol-gel derived glass gels. Density and compressive strength of the scaffolds decreased with increased in zinc contents. In vitro bioactivity of Zndoped AW glass-ceramics in a simulated body fluid (SBF) showed the formation of apatite layer on the surface within 7 days of soaking. However, increasing Zn addition increased the chemical durability of the AW glass-ceramics, resulting in …

Characterization And Drug Behavior In Shellac Wax Poloxamer Matrix Tablets Fabricated With Mold Technique, C. Choncheewa, T. Phaechamud

Journal of Metals, Materials and Minerals

Shellac wax is a waste product from shellac manufacturing process and has not been reported to be used as pharmaceutical matrix base. This study was to prepared and characterized shellac wax - poloxamer 407 matrix tablet comprising hydrophilic or hydrophobic drug which were prepared by molten technique. The ratios of poloxamer 407: shellac wax was varied and subsequently loaded with the different drug content before characterized with differential scaning calorimetry (DSC), thermogravimetric analysis (TGA) and powder x-ray diffractometry (PXRD). Drug release study was also performed for 25 mg drug loaded matrix tablet in distilled water using dissolution apparatus II at …

Role Of Aluminum Monostearate On Heat Treated-Chitosan Sponges Properties, K. Yodkhum, T. Phaechamud

Journal of Metals, Materials and Minerals

Heat treatment can be employed to modify properties such as biocompatibility and degradation rate of chitosan-based materials. However, heat treatment generally has effect on worsening of physical properties of the biomaterials. Our previous study indicated that fatty additive; aluminum monostearate (Alst), could improve thermal stability of chitosan sponges. Aim of this study is to investigate an effect of amount of Alst on physicochemical properties of chitosan sponges treated by different heat treatment methods. Two methods of heat treatment including moist heat (autoclave at 121°C, 15 psi for 5 minutes) and dry heat (vacuum heat at 110°C for 24 hours) were …

Preparation And Characterization Of Highly Filled Graphite-Based Polybenzoxazine Composites, A. Pengdam, S. Rimdusit

Journal of Metals, Materials and Minerals

This research aims to study suitable preparation methods and to characterize highly filled graphite composites using polybenzoxazine as a matrix. The high loading of graphite filler was attained in the range of 40 to 80% by wt. due to the very low a-stage viscosity of the benzoxazine resin (BA-a) used. The suitable condition for the compression molding of the highly filled graphite-polybenzoxazine (PBA-a) composites was at temperature of 200°C, and pressure of 15 MPa in the hydraulic hot-press machine for 3 hours to assure a fully cured specimen. The densities of the obtained composites were found to be in a …

Effect Of Silicon On Subcritical Heat Treatment Behavior And Wear Resistance Of 16 Wt% Cr Cast Iron With 2 Wt% Mo, P. Kosasu, S. Inthidech, P. Srichareonchai, Y. Matsubara

Journal of Metals, Materials and Minerals

Effects of Si content on the hardness, decomposition of austenite and abrasive wear resistance during subcritical heat treatment of hypoeutectic 16 wt% Cr -2 wt% Mo cast irons were investigated. The hypoeutectic 16 wt%Cr-2wt% Mo cast irons with 0.5-2.0 wt% Si were prepared. The as-cast specimens were heated up to subcritical temperatures at 50 K intervals from 673K for 14.4 ks ,28.8 ks and 43.2 ks and then, cooled to the room temperature by fan air cooling. In the as-cast state, the hardness increased gradually as Si content increased to 1.5 wt% and then decreased rapidly. The size and the …

Twin-Jet Electropolishing Of Cast Sterling Silver Alloys Using Perchloric Acid And Potassium Cyanide Solutions, W. Kongmuang, T. Chairuangsri, C. Chanmuang

Journal of Metals, Materials and Minerals

Twin-jet electropolishing of Ag-4.87 wt%Cu-0.79 wt%Zn-0.09 wt%Si alloy was studied. Two electrolytes, i.e. potassium cyanide solution in distilled water and glycerol-perchloric acid solution in absolute ethanol, were used in the experiments. Effects of parameters including voltage and electrolyte concentration have been studied. Surface of polishing specimens and artifact formed were characterized by light microscopy and electron microscopy. In general, the potassium cyanide solution is a better electrolyte than the glycerol-perchloric acid solution. A more uniform polishing can be obtained from the potassium cyanide solution at the voltage higher than 5 V. Increasing of the potassium cyanide concentration reduced the electrical …

Study Of Dynamic Vulcanized Pla/Enr Tpv Filled With Various Organic Modified Mmt (Ommt), C. Thongpin, N. Kuttanate, K. Kampuang, N. Suwanwanit

Journal of Metals, Materials and Minerals

In this research, we investigated the crystallization behavior of PLA and properties of PLA/ENR thermoplastic vulcanizates (TPVs). ENR was compounded with phenolic resin and with PLA at the blend ratio of 40/60 by using an internal mixer at 170°C and rotor speed of 70 rpm. Three types of organic modified montmorillonite (OMMT) which are Cloisite® 15A, Cloisite® 20 A and Cloisite® 30B were also added at various contents during mixing. The TPVs were pressed to form thin film in a compression molding machine and cooled down under pressure for 10 minutes. Crystallization behavior, thermal properties and morphology of TPVs were …

Preparation And Catalytic Property Of High Surface Area Mixed Oxides From Calcination Of Mgcucr- And Mgcual-Layered Double Hydroxides, W. Trakarnpruk

Journal of Metals, Materials and Minerals

In this research work layered double hydroxides (LDHs) containing Mg, Cu and Cr(or Al) were prepared with starting Mg:Cu:Cr (or Al) molar ratio of 2:1:1. They were calcined at 500 ºC for 5 h to convert into corresponding mixed oxides possessing high surface area. The catalysts were characterized by chemical analysis (ICP), infrared spectroscopy (FTIR), thermal analysis (TGA/DTA), powder X-ray diffraction (XRD), surface area measurements and H2 temperature programmed reduction (TPR). Catalytic property of these mixed oxides catalysts were tested in the oxidation of ethylbenzene using tertbutylhydroperoxide as an oxidant without added solvent. The experimental results show that high conversion …

Small Specimen Test Techniques For Evaluating Radiation-Induced Changes In Mechanical Properties, Ellen Marie Rabenberg

Boise State University Theses and Dissertations

The mechanical properties of as-received and irradiated 304 stainless steel (304SS) were evaluated by the shear punch and miniature tensile techniques. A purpose of this study was to evaluate the shear punch technique itself, which is a less developed technique versus miniature tensile testing. This was accomplished in part by comparing yield and ultimate strengths obtained from shear punch and miniature tensile data. The tests were further correlated by evaluating the mechanical properties of aluminum 6061 and Inconels 600 and 718. A linear relationship was observed between the shear strength and tensile strength data, providing a correlation between the two …

Recrystallization Kinetics Of 3c Silicon Carbide Implanted With 400 Kev Cesium Ions, Daniel Denell Osterberg

Boise State University Theses and Dissertations

Polycrystalline 3C silicon carbide was implanted at room temperature with 400 keV cesium ions to a dose of 10¹⁶ ions·cm^-2. The samples were then annealed at 600 – 1000°C for 0-48 hours in ultra-high purity argon. The implanted zone of each sample was characterized by transmission electron microscopy and secondary ion mass spectroscopy. It is shown that the implantation resulted in a 217 ± 2 nm amorphous region with microstructural damage extending to approximately 250 nm below the surface. Recrystallization of the amorphous region was observed at 725°C, although minimal densification was observed until ≥ 800°C. Densification …

Simulations Of Artificial Neural Network With Memristive Devices, Thanh Thi Thanh Tran

Boise State University Theses and Dissertations

The memristor has been hypothesized to exist as the missing fourth basic circuit element since 1971 [1]. A memristive device is a new type of electrical device that behaves like a resistor, but can change and remember its internal resistance. This behavior makes memristive devices ideal for use as network weights, which will need to be adjusted as the network tries to acquire correct outputs through a learning process. Recent development of physical memristive-like devices has led to an interest in developing artificial neural networks with memristors.

In this thesis, a circuit for a single node network is designed to …

Fabrication Of Solid Solution Tungsten-Rhenium Alloys By High Energy Ball Milling And Spark Plasma Sintering, Cory C. Sparks

Boise State University Theses and Dissertations

Tungsten-rhenium powders of varying compositions were fabricated by spark plasma sintering (SPS). In initial exploration of the parameter space, W-25 at% Re powders were blended and consolidated by SPS at 1500 to 1900°C with sintering dwell times of 0 to 60 minutes. In addition, the influence of milling was investigated. W-25 at% Re powders were high-energy ball milled at 200 to 400 rpm for 5 hours and consolidated at 1700°C with sintering dwell times of 0 to 60 minutes. The sample densities, grain sizes, porosities, contamination level, and hardness values were measured. The intermetallic content, specifically the fraction of σ-phase, …

The Development And Packaging Of A High-Density, Three-Phase, Silicon Carbide (Sic) Motor Drive, Jared Hornberger

Graduate Theses and Dissertations

Technology advances within the power electronics field are resulting in systems characterized by higher operating efficiencies, reduced footprint, minimal form factor, and decreasing mass. In particular, these attributes and characteristics are being inserted into numerous consumer applications, such as light-emitting diode lighting, compact fluorescent lighting, smart phones, and tablet PCs, to industrial applications that include hybrid, electric, and plug-in electric vehicles and more electric aircraft. To achieve the increase in energy efficiency and significant reduction in size and mass of these systems, power semiconductor device manufacturers are developing silicon carbide (SiC) semiconductor technology.

In this dissertation, the author discusses the …

Hybrid Plasmonic Nanoantennas: Fabrication, Characterization, And Application, Shengjie Zhai

UNLV Theses, Dissertations, Professional Papers, and Capstones

As optical counterpart of microwave antennas, plasmonic nanoantennas are important nanoscale devices for converting propagating optical radiation into confined/enhanced electromagnetic fields. Presently, nanoantennas, with a typical size of 200-500 nm, have found their applications in bio-sensing, bio-imaging, energy harvesting, and disease cure and prevention. With the device feature size of next generation IC goes down to 22 nm or smaller, and biological/chemical sensing reaches the Gene’s level, the sizes of the corresponding nanoantennas have to be scaled down to sub-100nm level. In the literature, these sub-100nm nanoantennas are referred as deep subwavelength nanoantennas as size of such miniaturized nanoantennas is …

Analysis Of Irrigation Decision Behavior And Forecasting Future Irrigation Decisions, Sanyogita Andriyas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Farmers play a pivotal role in food production. To be economically successful, farmers must make many decisions during the course of a growing season about the allocation of inputs to production. For farmers in arid regions, one of these decisions on any given day is whether to irrigate. This research is the first of its kind to investigate the probable reasons that lead a farmer to make irrigation decisions and use those reasons/factors to forecast future irrigation decisions. This study can help water managers and canal operators to estimate short-term irrigation demands, thereby gaining information that might be useful to …

A Multifunctional Solar Panel Antenna For Cube Satellites, Olutosin C. Fawole

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This work presented the design of a single antenna structure that can perform the functions of about four antennas. The antenna is to be applied on a new kind of very tiny satellites. These satellites are called CubeSats. In contrast to an ordinary antenna that works at a single frequency band, the antenna designed will be able to work at about three different usable frequencies. In addition, it will be possible to make the waves emitted by the antenna to have multiple senses of rotation or no rotation at all. The multiple functional capability of the antenna will lead to …

Flow Characteristics Of Arced Labyrinth Weirs, Nathan A. Christensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The need to accommodate larger reservoir discharge events has prompted the improvement or replacement of existing spillways. One possible spillway modification is the use of an in-reservoir arced labyrinth weir in place of a linear weir. Arced labyrinth weirs can increase crest length (more cycles) and have improved hydraulic efficiency in non-channelized approach flow applications, compared to traditional labyrinth weir applications.

In this study, arced labyrinth weir flow characteristics were observed for eleven different laboratory-scale model geometries at the Utah Water Research Laboratory. Rating (C_d vs. H_T/P) data and observations were recorded for each configuration, and discharge …

Developing A Framework To Analyze The Effect Of Mobile Technology Within A Department Of Transportation, Devin Squire

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mobile technology has the potential to have a substantial impact on governmental agencies. In order to understand the effects of mobile technology within an agency, an analysis has to be performed. This thesis presents two mobile applications that were developed to address specific areas of concern within the Utah Department of Transportation. It then, using mobile-technology specific surveys, provides a framework for effect analysis following application implementation. This framework employs both user and developer surveys to obtain data necessary to, through statistical methods, determine either a positive or a negative application induced effect. The analysis process and survey development used …

Biodiesel Production From Mixed Culture Algae Via A Wet Lipid Extraction Procedure, Ashik Sathish

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Development of renewable sources of energy has received significant interest due to the rising costs of energy and the environmental impact of using fossil fuels. Biodiesel production from renewable sources of oil has shown promise of helping to replace or reduce dependence on petroleum based diesel thereby reducing demand for crude oil. Microalgae have been considered as a strong candidate for the production of large quantities of renewable oil for biodiesel production.

Microalgae are single cell photosynthetic organisms that posses the capability to produce renewable oil at rates much faster than land based plants and crops. In addition, microalgae can …