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Model For The Electrolysis Of Water And Its Use For Optimization, Roger Lascorz, Javier E. Hasbun Dr 2016 Georgia Institute of Technology

Model For The Electrolysis Of Water And Its Use For Optimization, Roger Lascorz, Javier E. Hasbun Dr

Georgia Journal of Science

The goal of this research was to study the optimization of the electrolysis of water both theoretically and experimentally. For accuracy, 3 hr experiments were made with measurements recorded every 15 min. The results show that a better model than the classical one is needed for water electrolysis. A new model that fits experimental data better is proposed. The results of this new model not only predict hydrogen production in electrolysis of water better, but show a way to predict gas production of any liquid as well as what voltage to use to optimize it.


Experimental Building Demonstration Model With Viscous Fluid Dampers, Blake Thomas Reeve, Brianna Jean Kufa, Aden Malek Stepanians, Sophie Carmion Ratkovich 2016 California Polytechnic State University, San Luis Obispo

Experimental Building Demonstration Model With Viscous Fluid Dampers, Blake Thomas Reeve, Brianna Jean Kufa, Aden Malek Stepanians, Sophie Carmion Ratkovich

Architectural Engineering

The Architectural Engineering major places a heavy emphasis on structural dynamics and the role of wind and seismic loading in building analysis and design. Buildings of high importance that are critical to community function, such as hospitals, often utilize supplemental damping devices like supplemental viscous fluid dampers or base isolators to reduce the overall demands on the structural system. The design and analysis of these dampers are typically not taught at the undergraduate level, and is frequently performed by mechanical engineers, in lieu of structural engineers.

To better understand and research building behavior with supplemental damping devices, our multi-disciplinary team …


Zno Thin Films Generated By Ex-Situ Thermal Oxidation Of Metallic Zn For Photovoltaic Applications, Kovas Zygas 2016 Macalester College

Zno Thin Films Generated By Ex-Situ Thermal Oxidation Of Metallic Zn For Photovoltaic Applications, Kovas Zygas

Macalester Journal of Physics and Astronomy

ZnO thin films that function as either transparent conducting oxides in solid-state photovoltaic cells or as nanocrystalline dye-absorbers in dye-sensitized solar cells have the potential to reduce the cost of producing electricity from solar energy. Although there exist many methods to produce ZnO thin films, the most economical and practical method may be oxidation of metallic Zn thin films. This research examined the utility of ex-situ thermal oxidation of DC magnetron sputtered Zn thin films in generating useful ZnO thin films for these photovoltaic applications. We annealed Zn thin films in air at 570° C in order to produce ZnO …


Enhanced Adhesion Of Superhydrophobic Zno Surface, liqiu zheng Dr., Chan Kwaichow B. 2016 Albany State University

Enhanced Adhesion Of Superhydrophobic Zno Surface, Liqiu Zheng Dr., Chan Kwaichow B.

Georgia Journal of Science

The superhydrophobicity and the strong solid-liquid adhesion of the dually structured ZnO surface are attributed to the suitable size of microstructure and nanostructure. This phenomenon, so different from the Lotus effect, can be called the Petal effect— the super hydrophobicity and the enhanced solid-liquid adhesion coexist on the same surface. The Cassie impregnating model was proposed to understand the underlying reason.


Reflective Efficiencies Of Materials For Applications Of Bifacial Solar Cells, Michael Metter 2016 Linfield College

Reflective Efficiencies Of Materials For Applications Of Bifacial Solar Cells, Michael Metter

Senior Theses

The bifacial solar cell is superior to its monofacial predecessor due to its ability to convert both incident light on top and reflected light from below into energy. The scattering of the reflected light is affected by the property of the material on which it is interacting. To date, little work has been contributed to studying the properties of these materials to determine optimal quantities for bifacial solar cells. In the first experiment, reflective efficiencies compared to the angle of reflection were explored for different grit of sandpaper in order to develop an understanding of how surface texture impacts reflectivity. …


A New Take On Testing: Evaluating Design Systems In Response To The Recent Natural Disaster In Nepal, Jazmine L. Brown 2016 University of San Francisco

A New Take On Testing: Evaluating Design Systems In Response To The Recent Natural Disaster In Nepal, Jazmine L. Brown

Creative Activity and Research Day - CARD

In this thesis project I analyze the destruction of the 2015 earthquake in Nepal, specifically in the structural and architectural collapse. I have focused my research on the areas with greatest documented destruction and vulnerability, specifically Kathmandu and the settlements in the Middle Hills. The introduction of a new lateral testing mechanism can provided much needed information on the seismic strengths of vernacular construction methods.


Failure Of Surface Color Cues Under Natural Changes In Lighting, David H. Foster, Iván Marín-Franch 2016 University of Manchester

Failure Of Surface Color Cues Under Natural Changes In Lighting, David H. Foster, Iván Marín-Franch

MODVIS Workshop

Color allows us to effortlessly discriminate and identify surfaces and objects by their reflected light. Although the reflected spectrum changes with the illumination spectrum, cone photoreceptor signals can be transformed to give useful cues for surface color. But what happens when both the spectrum and the geometry of the illumination change, as with lighting from the sun and sky? Is it possible, as a matter of principle, to obtain reliable cues by processing cone signals alone? This question was addressed here by estimating the information provided by cone signals from time-lapse hyperspectral radiance images of five outdoor scenes under natural …


Optical Analysis And Fabrication Of Micro And Nanoscale Plasmonically Enhanced Devices, Avery M. Hill 2016 University of Arkansas, Fayetteville

Optical Analysis And Fabrication Of Micro And Nanoscale Plasmonically Enhanced Devices, Avery M. Hill

Physics Undergraduate Honors Theses

Plasmonic nanostructures have been shown to act as optical antennas that enhance optical devices due to their ability to focus light below the diffraction limit of light and enhance the intensity of the incident light. This study focuses on computational electromagnetic (CEM) analysis of two devices: 1) GaAs photodetectors with Au interdigital electrodes and 2) Au thin-film microstructures. Experiments showed that the photoresponse of the interdigital photodetectors depend greatly on the electrode gap and the polarization of the incident light. Smaller electrode gap and transverse polarization give rise to a larger photoresponse. It was also shown that the response from …


The Evaluation And Implementation Of Magnetic Fields For Large Strain Uniaxial And Biaxial Cyclic Testing Of Magnetorheological Elastomers., Dave Gorman, Niall Murphy, Ray Ekins, Stephen Jerrams 2016 Technological University Dublin

The Evaluation And Implementation Of Magnetic Fields For Large Strain Uniaxial And Biaxial Cyclic Testing Of Magnetorheological Elastomers., Dave Gorman, Niall Murphy, Ray Ekins, Stephen Jerrams

Articles

Magnetorheological Elastomers (MREs) are “smart” materials whose physical properties are altered by the application of magnetic fields. In previous studies the properties of MREs have been evaluated under a variety of conditions, however little attention has been paid to the recording and reporting of the magnetic fields used in these tests [1]. Currently there is no standard accepted method for specifying the magnetic field applied during MRE testing. This study presents a detailed map of a magnetic field applied during MRE tests as well as providing the first comparative results for uniaxial and biaxial testing under high strain fatigue test …


Optical Analysis And Fabrication Of Micro And Nanoscale Plasmonically Enhanced Devices, Avery M. Hill 2016 University of Arkansas, Fayetteville

Optical Analysis And Fabrication Of Micro And Nanoscale Plasmonically Enhanced Devices, Avery M. Hill

Mechanical Engineering Undergraduate Honors Theses

Plasmonic nanostructures have been shown to act as optical antennas that enhance optical devices due to their ability to focus light below the diffraction limit of light and enhance the intensity of the incident light. This study focuses on computational electromagnetic (CEM) analysis of two devices: 1) GaAs photodetectors with Au interdigital electrodes and 2) Au thin-film microstructures. Experiments showed that the photoresponse of the interdigital photodetectors depend greatly on the electrode gap and the polarization of the incident light. Smaller electrode gap and transverse polarization give rise to a larger photoresponse. It was also shown that the response from …


Polytetraflouroethylene Thin Coatings For Tribological Applications, Samuel L. Jenkins 2016 University of Arkansas, Fayetteville

Polytetraflouroethylene Thin Coatings For Tribological Applications, Samuel L. Jenkins

Physics Undergraduate Honors Theses

Mechanical components with lower coefficients of friction decrease the amount of energy dissipated by the system due to friction. Coating these components would decrease the coefficients of friction between surfaces without sacrificing the strength of the components. A polytetrafluoroethylene (PTFE) layer adhered through a polydopamine (PDA) layer on a steel substrate will reduce the coefficient of friction on the substrate surface. This paper discusses different methods for attempting to increase the uniformity of the PDA layer as well as decrease the PDA coating time. Methods for increasing uniformity include using a particle disperser instead of a magnet stir rod, changing …


Spontaneous Parametric Down Conversion Of Photons Through Β-Barium Borate, Luke Horowitz 2016 California Polytechnic State University, San Luis Obispo

Spontaneous Parametric Down Conversion Of Photons Through Β-Barium Borate, Luke Horowitz

Physics

An apparatus for detecting pairs of entangled 405nm photons that have undergone Spontaneous Parametric Down Conversion through β-Barium Borate is described. By using avalanche photo-diodes to detect the low-intensity converted beam and a coincidence module to register coincident photons, it is possible to create an apparatus than can be used to perform quantum information experiments under a budget appropriate for an undergraduate physics lab.


Particle Image Velocimetry Design & Installation, Zach Ritchie 2016 University of Arkansas, Fayetteville

Particle Image Velocimetry Design & Installation, Zach Ritchie

Mechanical Engineering Undergraduate Honors Theses

This work will mainly focus on the design, construction, and installation of the Particle Image Velocimetry (PIV) system in the Chemical Hazards Research Center wind tunnel. The PIV system utilizes a Class IV (double pulsed) laser, optics to produce a light sheet, timing circuitry, and a high-resolution camera (with buffered output) to measure a system’s velocity (two-dimensional) field by determining the displacement of particles over the time between laser pulses. For maximum mobility and functionality, the PIV system was installed in the center of the tunnel on a moveable cart with the laser and camera mounted to an adjustable support. …


Experimental And Computational Studies Of Cortical Neural Network Properties Through Signal Processing, Wesley Patrick Clawson 2016 University of Arkansas, Fayetteville

Experimental And Computational Studies Of Cortical Neural Network Properties Through Signal Processing, Wesley Patrick Clawson

Graduate Theses and Dissertations

Previous studies, both theoretical and experimental, of network level dynamics in the cerebral cortex show evidence for a statistical phenomenon called criticality; a phenomenon originally studied in the context of phase transitions in physical systems and that is associated with favorable information processing in the context of the brain. The focus of this thesis is to expand upon past results with new experimentation and modeling to show a relationship between criticality and the ability to detect and discriminate sensory input. A line of theoretical work predicts maximal sensory discrimination as a functional benefit of criticality, which can then be characterized …


Spin Polarisation Oft ̄Tγγproduction At Nlo+Ps With Gosam Interfaced To Madgraph5_Amc@Nlo, Hans van Deurzen, Rikkert Frederix, Valentin Hirschi, Gionata Luisoni, Pierpaolo Mastrolia, Giovanni Ossola 2016 Max-Planck-Institut für Physik

Spin Polarisation Oft ̄Tγγproduction At Nlo+Ps With Gosam Interfaced To Madgraph5_Amc@Nlo, Hans Van Deurzen, Rikkert Frederix, Valentin Hirschi, Gionata Luisoni, Pierpaolo Mastrolia, Giovanni Ossola

Publications and Research

We present an interface between the multipurpose Monte Carlo toolMadGraph5_aMC@NLOand the automated amplitude generator GoSam. As a first application of this novel framework, we compute the NLO corrections topp→t ̄tHandpp→t ̄tγγmatched to a parton shower. In the phenomenological analyses of these processes, we focus our attention on observables which are sensitive to the polarisation of the top quarks.


Nonlinear Control Of A Thermoacoustic System With Multiple Heat Sources And Actuators, Mikael O. Molina Sandoval 2016 Embry-Riddle Aeronautical University

Nonlinear Control Of A Thermoacoustic System With Multiple Heat Sources And Actuators, Mikael O. Molina Sandoval

Doctoral Dissertations and Master's Theses

Thermoacoustic instabilities can occur in thermal devices when unsteady heat release is coupled with pressure perturbations. This effect results in excitation of Eigen-acoustic modes of the system. These instabilities can lead to unpredictable behavior of the system. Gas-turbine combustion systems are especially prone to this phenomenon reducing their overall efficiency. Additionally, due to the nature of the combustion, the turbines end up releasing undesired amounts of harmful chemicals to the atmosphere, such as Nitrous Oxide (NOX).

A Rijke tube, representing a resonator with a mean flow and a concentrated heat source, is a convenient system to study the thermoacoustic phenomena. …


Capturing Atmospheric Effects On 3-D Millimeter Wave Radar Propagation Patterns, Richard D. Cook 2016 Air Force Institute of Technology

Capturing Atmospheric Effects On 3-D Millimeter Wave Radar Propagation Patterns, Richard D. Cook

Theses and Dissertations

The need to model millimeter wave (MMW) radar propagation is imperative to proper design of aeronautical, civil, and military systems. Traditional radar propagation modeling is done using a path transmittance with little to no input for weather and atmospheric conditions. As radar advances into the MMW regime, atmospheric effects, such as attenuation and refraction, become more pronounced than at traditional radar wavelengths. The DoD High Energy Laser Joint Technology Offices High Energy Laser End-to-End Operational Simulation (HELEEOS), in combination with the Laser Environmental Effects Definition and Reference (LEEDR) code, is a powerful tool for simulating laser propagation and effects tied …


Zncdmgse As A Materials Platform For Advanced Photonic Devices: Broadband Quantum Cascade Detectors And Green Semiconductor Disk Lasers, Joel De Jesus 2016 CUNY Graduate Center

Zncdmgse As A Materials Platform For Advanced Photonic Devices: Broadband Quantum Cascade Detectors And Green Semiconductor Disk Lasers, Joel De Jesus

Dissertations, Theses, and Capstone Projects

The ZnCdMgSe family of II-VI materials has unique and promising characteristics that may be useful in practical applications. For example they can be grown lattice matched to InP substrates with lattice matched bandgaps that span from 2.1 to 3.5 eV, they can be successfully doped n-type, have a large conduction band offset (CBO) with no intervalley scattering present when strained, they have lower average phonon energies, and the InP lattice constant lies in the middle of the ZnSe and CdSe binaries compounds giving room to experiment with tensile and compressive stress. However they have not been studied in detail for …


Early Afternoon Concurrent Panel Sessions: Commercial Space Industry Snapshot: Presentation: Small Catapult-Assisted Horizontal-Launch Reusable Rbcc Ssto Spaceplane For Economical Short-Duration Leo Access, Nihad E. Daidzic, 2016 AAR Aerospace Consulting, LLC

Early Afternoon Concurrent Panel Sessions: Commercial Space Industry Snapshot: Presentation: Small Catapult-Assisted Horizontal-Launch Reusable Rbcc Ssto Spaceplane For Economical Short-Duration Leo Access, Nihad E. Daidzic,

Aviation / Aeronautics / Aerospace International Research Conference

This article discusses the conceptual design, flight trajectory calculations, and utilization of the possible future horizontally-launched reusable Single-Stage-to-Orbit (SSTO) spaceplane for small payload short-duration manned/unmanned access to Low-Earth-Orbit (LEO). The 10,000 lb spaceplane would use 5,000 ft catapult-assist horizontal-launch facility and conduct powered approach and landing on conventional horizontal paved runways following the gliding atmospheric re-entry. To increase the economy of operation, the launch facility located at high elevations (4,000+ ft) equatorial region is required, such as, the plateaus in Kenya and Tanzania in Africa and/or Ecuador in South America. A 500-lb payload, including pilot-commander, is envisioned. The propulsion cycle …


Ferroelectric Characterization And Growth Optimization Of Thermally Evaporated Vinylidene Fluoride Thin Films, Keith Foreman, N. Hong, C. Labedz, C. Shearer, Stephen Ducharme, Shireen Adenwalla 2016 University of Nebraska-Lincoln

Ferroelectric Characterization And Growth Optimization Of Thermally Evaporated Vinylidene Fluoride Thin Films, Keith Foreman, N. Hong, C. Labedz, C. Shearer, Stephen Ducharme, Shireen Adenwalla

Shireen Adenwalla Papers

Organic thin films have numerous advantages over inorganics in device processing and price. The large polarization of the organic ferroelectric oligomer vinylidene fluoride (VDF) could prove useful for both device applications and the investigation of fundamental physical phenomena. A VDF oligomer thin film vacuum deposition process, such as thermal evaporation, preserves film and interface cleanliness, but is challenging, with successful deposition occurring only within a narrow parameter space. We report on the optimal deposition parameters for VDF oligomer thin films, refining the parameter space for successful deposition, resulting in a high yield of robust ferroelectric films. In particular, we investigate …


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