Engineering Commons^™

Crystallization Of Carnallite From Kcl-Mgcl2 Brine Solutions By Solvent Evaporation Process And Its Structural And Mechanical Characterization, J Podder, S Gao, R W Evitts, Rw Besant, D Matthews

Journal of Metals, Materials and Minerals

Carnallite crystals have been synthesized from brine solutions at room temperature (23C) by solvent evaporation growth technique to show the effect of the concentration of potassium chloride (KCl) and magnesium chloride (MgCl2) on the growth, structural and mechanical properties of the crystal. Transparent and pseudo-hexagonal shape carnallite crystals with the dimension of 4 5 2 mm to 16 13 3 mm were grown. The crystals were characterized by powder X-ray diffraction and the lattice parameters were found to be a = 9.598 b = 16.141and c = 22.519 space group: Pnna, Z: 12, ? = ? = ? = 90 …

Effect Of Heat Treatment On Phase Transformation Of Tio2 And Its Reflectance Properties, K Archaapinun, N Witit-Anun, P Visuttipitukul

Journal of Metals, Materials and Minerals

Titanium dioxide (TiO2) anti reflection coating film applied for solar cell application, gains more interest due to the insufficient energy problems today. Titanium dioxide can be found in several forms, and the most stable phase is rutile. This research aims to study effect of heat treatment on phase transformation of TiO2 and its effect on reflectance property. Titanium dioxide film was coated on silicon wafer by DC magnetron sputtering to obtain 190 nm and 420 nm thicknesses. Then, it was heat treated at 900C for 1 and 4 hours under ambient atmosphere. Phases and surface morphologies before and after heat …

Investigation Of Supersaturated Silver Alloys For High Hardness Jewelry Application, S Praiphruk, G Lothongkum, E Nisaratanaporn, B Lohwongwatana

Journal of Metals, Materials and Minerals

Sterling silver is one of the most widely used precious metal alloys in jewelry industry. 92.5 wt% silver content is the standard for sterling products, while 7.5 wt% is reserved for other alloying elements. Because the mechanical properties of pure silver such as yield strength and hardness are extremely low. In the bounds of 7.5 wt% solute addition, different approaches have been introduced in order to improve the properties of sterling silver. For example, to increase the hardness of the jewelry pieces, metallurgists introduced age hardening, cold working, and surface treatments. We reported on the trend of intrinsic hardness increase …

Comparison Of Ball-On-Disc And Taber Wear Tests In Assessing Wear Performance Of Electrolessly-Deposited Alloys, K Theeratatpong, S Danchaivijit, Y Boonyongmaneerat

Journal of Metals, Materials and Minerals

In the industry, a Taber wear test is commonly employed to assess the wear resistance of coatings, which are applied on a panel of relatively large scales. On the other hand, other wear testing methods, such as ball-on-disc, is preferred in laboratory settings, as they require smaller test specimens and can determine coefficient of friction. In this study, we systematically compare the differences of Taber wear and ball-on disc by evaluating with an electrolessly-deposited Ni-P alloy systems. The Taber wear shows purely abrasive wear, whereas the ball-on-disc test offers a complex blend of wear mechanisms, and provides the coefficient of …

An Investigation Into The Water Budget And The Management Of The Snake River System, John Whitney Hildreth

Boise State University Theses and Dissertations

Future climate change poses a major conceptual challenge to the availability of water resources due to the uncertainty involved with changes to the hydrologic cycle. Over the past decades, observed warming temperatures across the Western United Sates have shown significant impacts on river basin scale hydrology. This research uses physically based modeling tools to assess the hydrologic impacts of climate change in the Snake River Basin. Physically based hydrologic modeling studies of future climate do not typically take into account interactions between groundwater and surface water. To account for these interactions, the Variable Infiltration Capacity model is coupled with the …

Influence Of Microstructure On The Propagation Of Fatigue Cracks In Inconel 617, Benjiman Michael Albiston

Boise State University Theses and Dissertations

Inconel 617 is a candidate material for use in the intermediate heat exchanger of the Next Generation Nuclear Plant. Because of the high temperatures and the fluctuations in stress and temperature, the fatigue behavior of the material is important to understand. The goal of this study was to determine the influences of the microstructure during fatigue crack propagation. For this investigation, Inconel 617 compact tension samples, fatigue tested by Julian Benz at the Idaho National Laboratory, were obtained. The testing conditions included two environments at 650 °C (lab air and impure-He) and varied testing parameters including: loading waveform (triangular, trapezoidal), …

Impact Of Alkaline Doping And Reducing Conditions On Lafeo3, Geoffrey L. Beausoleil

Boise State University Theses and Dissertations

Efficient and reliable materials for gas separation, syngas production, and hybrid nuclear power plants must be capable of reliably operating at a high-temperature range of 700-1000°C and under exposure to highly oxidizing and reducing conditions. Candidate materials for these applications include alkaline metal doped lanthanum ferrite.

In the first study, the impact of A site substitution by different alkaline metals on lanthanum ferrite (LMF, M=Ca, Sr, and Ba) was investigated. The study focused on thermal expansion near the Néel transition temperature and a magneto-elastic contribution to thermal expansion was identified for each sample. Iron oxidation, Fe³⁺ to Fe^{4+ …}

Characterization And Feasibility Of A Portable Oxygen Concentrator For Use With A Mass Casualty Ventilator, Paul Robert Williams

Boise State University Theses and Dissertations

The American Association for Respiratory Care has reported a need to stockpile 5,000-10,000 mass casualty ventilators with supplemental oxygen in preparation for pandemic emergencies (1). The American Medical Association specifies oxygen concentrators supply oxygen at 5 liters per minute at ≥90% purity (2). However, these design specifications may not be the most efficient use of system resources in portable oxygen concentrators using pressure swing adsorption. A testbed was developed to investigate the system performance of an oxygen concentrator while altering the system inlet and outlet pressures and flow rates. This investigation demonstrates that a more efficient portable oxygen concentrator, which …

Analysis Of A Miniature Radio Frequency Ion Thruster With An Inductively Coupled Plasma Source, Peter Paul Bumbarger

Boise State University Theses and Dissertations

The performance of a 2 cm miniature ion thruster was analyzed. A thruster of this size was predicted to produce a thrust of 200 μN. The plasma density was measured against rf input power and propellant flow rate for three configurations: the ICP source by itself; the ICP source with discharge chamber; and finally, the ICP source, the discharge chamber, and the permanent magnet cusp system. Once the optimum case was determined, electrostatic grids were added and thrust measurements were taken with a set of segmented ion collector plates.

The miniature rf ion thruster obtained a thrust of 22.35 μN …

Evaluation Of Alternate Mouthpiece Material Types To Minimize Vibrations And Heat Loss - The Research And Execution Of Prototypes, Kristen Bobuk

Theses, Dissertations and Capstones

This paper is based on the idea of current horn mouthpieces being made solely out of brass with a limited market of stainless steel and titanium with plating being silver or gold. This is an opportunity to explore alternate materials; specifically steel, cast iron and aluminum for the base material and chrome, copper and nickel for plating materials. Readers will learn about metal properties such as hardness, thermal conductivity and specific heat and learn why certain materials are more beneficial than others.

Dopaminergic Modulation Of Memory And Affective Processing In Parkinson Depression, Lee X. Blonder, John T. Slevin, Richard J. Kryscio, Catherine A. Martin, Anders H. Andersen, Charles D Smith, Frederick A. Schmitt

Magnetic Resonance Imaging and Spectroscopy Center Faculty Publications

Depression is common in Parkinson's disease and is associated with cognitive impairment. Dopaminergic medications are effective in treating the motor symptoms of Parkinson's disease; however, little is known regarding the effects of dopaminergic pharmacotherapy on cognitive function in depressed Parkinson patients. This study examines the neuropsychological effects of dopaminergic pharmacotherapy in Parkinsonian depression. We compared cognitive function in depressed and non-depressed Parkinson patients at two time-points: following overnight withdrawal and after the usual morning regimen of dopaminergic medications. A total of 28 non-demented, right-handed patients with mild to moderate idiopathic Parkinson's disease participated. Ten of these patients were depressed according …

Diffuse Correlation Spectroscopy (Dcs) For Assessment Of Tissue Blood Flow In Skeletal Muscle: Recent Progress, Yu Shang, Katelyn Gurley, Guoqiang Yu

Biomedical Engineering Faculty Publications

Near-infrared diffuse correlation spectroscopy (DCS) is an emerging technology for monitoring blood flow in various tissues. This article reviews the recent progress of DCS for the assessment of skeletal muscle blood flow, including the developments in technology allowing use during dynamic exercise and muscular electrical stimulation, the utilization for diagnosis of muscle vascular diseases, and the applications for evaluating treatment effects. The limitations of current DCS studies and future perspective are finally discussed.

Contrast Adaptation In The Lateral Eye Of Limulus Polyphemus, Tchoudomira Valtcheva

USF Tampa Graduate Theses and Dissertations

Luminance and contrast adaptation are neuronal mechanisms that the retina applies for continuous adjustment to light sensitivity though a collection of cellular and synaptic mechanisms distributed across the retinal network, thus accommodating the wide input range of the visual system within the constricted output range of retinal ganglion cells. Luminance mean adaptation has been demonstrated in the output neurons of the invertebrate eye (eccentric cells), and the aim of the study was to investigate whether the homology in visual processing extends to luminance variance (contrast) adaptation as well. The spike trains of individual eccentric cells were recorded from live horseshoe …

Skeletal Muscle Contraction Simulation: A Comparison In Modeling, Jonathan M. Ford

USF Tampa Graduate Theses and Dissertations

Computer generated three-dimensional (3-D) models are being used at increasing rates in the fields of entertainment, education, research, and engineering. One of the aspects of interest includes the behavior and function of the musculoskeletal system. One such tool used by engineers is the finite element method (FEM) to simulate the physics behind muscle mechanics. There are several ways to represent 3-D muscle geometry, namely a bulk, a central line of action and a spline model. The purpose of this study is to exmine how these three representations affect the overall outcome of muscle movement. This is examined in a series …

La Yeguada Volcanic Vomplex In The Republic Of Panama: An Assessment Of The Geologic Hazards Using 40ar/39ar Geochronology, Karinne L. Knutsen, William I. Rose, Brian Jicha

Department of Geological and Mining Engineering and Sciences Publications

La Yeguada volcanic complex is one of three Quaternary volcanic centers in Panama. To assess potential geologic hazards, new samples were analyzed using argon analysis (⁴⁰Ar/³⁹Ar), and obtained the following: the most recent eruption occurred approximately 32,000 years ago at the Media Luna cinder cone; the youngest dated eruption from the main dome complex occurred 357 ± 19 ka, producing the Castillo dome unit; Cerro Picacho, a separate dacite dome 1.5 km east of the main complex is 4.47 ± 0.23 Ma; and the El Satro Pyroclastic Flow unit surrounds the northern portion of the volcanic …

Spectral Analysis Of Nonstationary Heart Rate Of Neonates Receiving Therapeutic Hypothermia Treatment, Tareq Al-Shargabi

Theses and Dissertations

We studied Heart Rate Variability (HRV) evolution during therapeutic hypothermia in newborns with hypoxic ischemic encephalopathy (HIE) using spectral analysis. We hypothesized that HRV measures are predictive of neurological outcome in babies with HIE. Non-stationarity in the data causes inaccurate quantification of the spectral power. A modification was proposed to power spectral analysis approach to mitigate the effect of non-stationarity. The modified and the standard approaches were applied to cardiac beat-to-beat intervals of newborns receiving hypothermia treatment. The performance of the approaches in distinguishing the RRi dynamics of two groups of newborns was assessed using area under the receiver operating …

Pvcrov : An Experimental Platform For Multi-Robot Control Systems, Nicholas Prince, Gregory Roos, Jennifer Semones, Chase Traficanti

Mechanical Engineering Senior Theses

As the field of multi-robot control systems grows, the demand for flexible, robust and precise multi-robot testbeds increases. Up to this point, the testbeds that do exist for testing multi-robot controllers are often expensive, hard to deploy, and typically constrained to a single plane of motion. These constraints limit the capacity to conduct research which is why team Autonomously Controlled Electromechanical Systems (ACES) has created the PVCROV system. PVCROV is a low cost, underwater platform for testing multi-robot control systems. By utilizing an underwater environment, ACES created a testbed that is not constrained to a single plane of motion. Additionally, …

Liquid Phase Stability Under An Extreme Temperature Gradient, Zhi Liang, Kiran Sasikumar, Pawel Keblinski

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Using Nonequilibrium Molecular Dynamics Simulations, We Subject Bulk Liquid to a Very High-Temperature Gradient and Observe a Stable Liquid Phase with a Local Temperature Well above the Boiling Point. Also, under This High-Temperature Gradient, the Vapor Phase Exhibits Condensation into a Liquid at a Temperature Higher Than the Saturation Temperature, Indicating that the Observed Liquid Stability is Not Caused by Nucleation Barrier Kinetics. We Show that, Assuming Local Thermal Equilibrium, the Phase Change Can Be Understood from the Thermodynamic Analysis. the Observed Elevation of the Boiling Point is Associated with the Interplay between the "Bulk" Driving Force for the Phase …

Experimental Determination And Equation Of State Modeling Of High-Pressure Fluid Behavior, Yue Wu

Theses and Dissertations

High-pressure solution behavior such as density and phase behavior is a critical fundamental property for the design and optimization of various chemical processes, such as distillation and extraction in the production and purification of oils, polymers, and other natural materials. In this PhD study, solution behavior data are experimentally determined and equation of state (EoS) modeled for n-hexadecane, n-octadecane, n-eicosane, methylcyclohexane, ethylcyclohexane, cis-1,2-dimethylcyclohexane, cis-1,4-dimethylcyclohexane, trans-1,4-dimethylcyclohexane, o-xylene, m-xylene, p-xylene, and 2-methylnaphthalene at temperatures to 525 K and pressures to 275 MPa. A variable-volume view cell coupled with a linear variable differential transformer is used for the high-pressure determination. The reported density …

In-Situ Study Of E-Beam Al And Hf Metal Deposition On Native Oxide Inp (100), H. Dong, Santosh Kc, A. Azcatl, W. Cabrera, X. Qin, B. Brennan, D. Zhernokletov, K. Cho, R. Wallace

Faculty Publications

The interfacial chemistry of thin Al (∼3 nm) and Hf (∼2 nm) metal films deposited by electron beam (e-beam) evaporation on native oxide InP (100) samples at room temperature and after annealing has been studied by in situ angle resolved X-ray photoelectron spectroscopy and low energy ion scattering spectroscopy. The In-oxides are completely scavenged forming In-In/In-(Al/Hf) bonding after Al and Hf metal deposition. The P-oxide concentration is significantly decreased, and the P-oxide chemical states have been changed to more P-rich oxides upon metal deposition. Indium diffusion through these metals before and after annealing at 250 °C has also been characterized. …

Design Of Engineered Biomaterial Architectures Through Natural Silk Proteins, Nicholas Kurland

Theses and Dissertations

Silk proteins have provided a source of unique and versatile building blocks in the fabrication of biomedical devices for addressing a range of applications. Critical to advancing this field is the ability to establish an understanding of these proteins in their native and engineered states as well as in developing scalable processing strategies, which can fully exploit or enhance the stability, structure, and functionality of the two constituent proteins, silk fibroin and sericin. The research outlined in this dissertation focuses on the evolution in architecture and capability of silks, to effectively position a functionally-diverse, renewable class of silk materials within …

Theory, Synthesis, And Application Of Adiabatic And Reversible Logic Circuits For Security Applications, Matthew Arthur Morrison

USF Tampa Graduate Theses and Dissertations

Programmable reversible logic is emerging as a prospective logic design style for implementation in modern nanotechnology and quantum computing with minimal impact on circuit heat generation. Adiabatic logic is a design methodology for reversible logic in CMOS where the current flow through the circuit is controlled such that the energy dissipation due to switching and capacitor dissipation is minimized. Recent advances in reversible logic using and quantum computer algorithms allow for improved computer architectures. Production of cost-effective Secure Integrated Chips, such as Smart Cards, requires hardware designers to consider tradeoffs in size, security, and power consumption. In order to design …

Ceas E-News 11.22.2013, College Of Engineering And Applied Sciences

College of Engineering and Applied Sciences News

Stryker Challenge, SAE Competition, Medieval Engineering Trebuchet Team

Systems And Methods For Detecting Molecular Interactions Using Magnetic Beads, Joshua P. Steimel, Charles E. Sing, Alfredo Alexander-Katz

Pacific Patents

Systems and methods are provided for detecting or measuring binding affinity between different compositions. The methods include contacting one or more magnetic beads having a surface including a first composition with a substrate having a surface including a second composition; applying a rotating magnetic field to the one or more magnetic beads effective to cause the one or more magnetic beads to move across the surface of the substrate; measuring the movement of the one or more magnetic beads across the substrate surface to determine a translational velocity; and determining a binding affinity between the first and second compositions from …

Investigation Of Thermal Cycle And Hardness Distribution In The Laser Cladding Of Aisi H13 Tool Steel Produced By A High Power Direct Diode Laser, Parisa Farahmand, Prabu Balu, Fanrong Kong, Radovan Kovacevic

Mechanical Engineering Research

Laser cladding (LC) of tool steel has significant application in rapid tooling, and surface coating for worn-out components in different industries. During the LC process, several phase transformations influence the microstructural and mechanical properties of the deposited layer. In order to successfully implement the LC process, it is essential to understand the relationship between the thermal cycle (heating and cooling), phase transformations, and the output quantities of the deposited layer. In this study a direct diode laser with a power of up to 8 kW was used to deposit AISI H13 tool steel on mild steel grade A36 substrate to …

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering: News & Publications (2013-2023)

• Accepting Applications for National Science Foundation: Research Experience for Undergraduates

College Of Engineering News, Georgia Southern University

College of Engineering & Computing: News & Publications (2010-2023)

• Fall 2013 War Games

Binding, Transcytosis And Biodistribution Of Anti-Pecam-1 Iron Oxide Nanoparticles For Brain-Targeted Delivery, Mo Dan, David B. Cochran, Robert A. Yokel, Thomas D. Dziubla

Pharmaceutical Sciences Faculty Publications

OBJECTIVE: Characterize the flux of platelet-endothelial cell adhesion molecule (PECAM-1) antibody-coated superparamagnetic iron oxide nanoparticles (IONPs) across the blood-brain barrier (BBB) and its biodistribution in vitro and in vivo.

METHODS: Anti-PECAM-1 IONPs and IgG IONPs were prepared and characterized in house. The binding affinity of these nanoparticles was investigated using human cortical microvascular endothelial cells (hCMEC/D3). Flux assays were performed using a hCMEC/D3 BBB model. To test their immunospecificity index and biodistribution, nanoparticles were given to Sprague Dawley rats by intra-carotid infusion. The capillary depletion method was used to elucidate their distribution between the BBB and brain parenchyma.

RESULTS: Anti-PECAM-1 …

Hot Spot Identification And Analysis Methodology, Jacob S. Farnsworth

Theses and Dissertations

The Utah Department of Transportation (UDOT) Traffic and Safety Division continues to advance the safety of roadway sections throughout the state. To aid UDOT in meeting their goal the Department of Civil and Environmental Engineering at Brigham Young University (BYU) has worked with the Statistics Department in developing analysis tools for safety. The most recent of these tools has been the development of a hierarchical Bayesian Poisson Mixture Model (PMM) statistical model of traffic crashes and safety on UDOT roadways statewide and the integration of the results of this model in a Geographic Information System (GIS) framework. This research focuses …

Visuo-Proprioceptive Interactions During Adaptation Of The Human Reach, Timothy Judkins, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

We examined whether visual and proprioceptive estimates of transient (mid-reach) target capture errors contribute to motor adaptation according to the probabilistic rules of information integration used for perception. Healthy adult humans grasped and moved a robotic handle between targets in the horizontal plane while the robot generated spring-like loads that varied unpredictably from trial-to-trial. For some trials, a visual cursor faithfully tracked hand motion. In others, the handle's position was locked and subjects viewed motion of a point-mass cursor driven by hand forces. In yet other trials, cursor feedback was dissociated from hand motion or altogether eliminated. We used time- …