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Full-Text Articles in Materials Science and Engineering

Evaluation Of Alternate Mouthpiece Material Types To Minimize Vibrations And Heat Loss - The Research And Execution Of Prototypes, Kristen Bobuk Dec 2013

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.


Spectroscopic, Thermal, And Physical Analysis Of The Raw Materials In Europium Doped Cesium Strontium Iodide Scintillator, Bonnie Dell Blalock Dec 2013

Spectroscopic, Thermal, And Physical Analysis Of The Raw Materials In Europium Doped Cesium Strontium Iodide Scintillator, Bonnie Dell Blalock

Masters Theses

Scintillators are widely used in homeland security applications that utilize gamma-ray spectroscopy. An ideal scintillator for this purpose should possess a high effective atomic number, high light yield, and good energy resolution. The scintillator CsSrI3: Eu [cesium strontium iodide: europium], recently developed at the Scintillation Materials Research Center, has excellent properties. Recent efforts have been made to evaluate the basic thermal properties and IR spectra of the compound’s raw materials as part of a project to improve the quality of grown crystals. Fourier transform infrared spectroscopy of high purity anhydrous CsI [cesium iodide], SrI2 [strontium iodide], and …


Mode I Fracture Toughness Of Eight-Harness-Satin Carbon Cloth Weaves For Co-Cured And Post-Bonded Laminates, Josh E. Smith Dec 2013

Mode I Fracture Toughness Of Eight-Harness-Satin Carbon Cloth Weaves For Co-Cured And Post-Bonded Laminates, Josh E. Smith

Master's Theses

Mode I interlaminar fracture of 3k 8-Harness-Satin Carbon cloth, with identical fill and weft yarns, pre-impregnated with Newport 307 resin was investigated through the DCB test (ASTM D5528). Crack propagations along both the fill and weft yarns were considered for both post-bonded (co-bonded) and co-cured laminates. A patent-pending delamination insertion method was compared to the standard Teflon film option to assess its applicability to mode I fracture testing. The Modified Beam Theory, Compliance Calibration method, and Modified Compliance Calibration method were used for comparative purposes for these investigations and to evaluate the validity of the proposed Equivalent Stiffness (EQS) method. …


Synthesis Of Graphene Nanomaterials And Their Application In Electrochemical Energy Storage, Guoping Xiong Oct 2013

Synthesis Of Graphene Nanomaterials And Their Application In Electrochemical Energy Storage, Guoping Xiong

Open Access Dissertations

The need to store and use energy on diverse scales in a modern technological society necessitates the design of large and small energy systems, among which electrical energy storage systems such as batteries and capacitors have attracted much interest in the past several decades. Supercapacitors, also known as ultracapacitors, or electrochemical capacitors, with fast power delivery and long cycle life are complementing or even replacing batteries in many applications. The rapid development of miniaturized electronic devices has led to a growing need for rechargeable micro-power sources with high performance. Among different sources, electrochemical micro-capacitors or micro-supercapacitors provide higher power density …


Soil Nutrient Availability Properties Of Biochar, Nicole C. Esposito Oct 2013

Soil Nutrient Availability Properties Of Biochar, Nicole C. Esposito

Master's Theses

Biochar’s high porosity and negative surface charge allows for numerous soil and plant benefits such as increased water retention, high nutrient availability, and plant growth. By analysing biochar’s effect of all of these factors, a system can be put in place in which soils can be remediated with the proper soil amendments. This report discusses and tests the effects of varying rates of biochar on pH levels, cation exchange capacity, and nutrient exchangeability (of calcium, magnesium, sodium, and potassium) in soil. Corn plants were also grown in soils of varying amendment types and analysed for plant growth and germination to …


Development Of Novel Nanomaterials For Lithium-Air And Sodium-Air Batteries, Yongliang Li Aug 2013

Development Of Novel Nanomaterials For Lithium-Air And Sodium-Air Batteries, Yongliang Li

Electronic Thesis and Dissertation Repository

Lithium-air and sodium-air batteries are promising energy storage systems for future smart grids and electric vehicles due to their extremely high theoretical energy densities. However, electrode material development and architecture design for cathode as well as the battery cycleability are big challenges for these batteries. This research aims at developing various novel nanomaterials with desired morphology and structure as cathode materials for lithium-air and sodium-air batteries.

For lithium-air batteries, various carbon nanostructured cathodes were developed. They include: (1) Carbon black nanoparticles were treated under ammonia and carbon dioxide/hydrogen atmospheres and the surface area, porosity, defects, nitrogen-doping, and functional groups were …


An Investigation Of Energy Migration In Rare Earth Oxyorthosilicate Scintillation Materials, Harold Edward Rothfuss Aug 2013

An Investigation Of Energy Migration In Rare Earth Oxyorthosilicate Scintillation Materials, Harold Edward Rothfuss

Doctoral Dissertations

In most scintillator applications, the energy resolution is an important scintillation property and is related to other scintillator properties. In order to observe how these properties relate to the energy resolution, a simulation was created to quantify most of these characteristics for a LSO:Ce scintillator. These results were validated with good agreement to experimental results. From the separable components of the simulation, an understanding of the contributions to the energy resolution broadening was developed. A thought to improve the energy resolution by improving the energy migration was tested by observing and modifying the scintillation kinetics of YSO:Ce. The scintillation kinetics …


Plasmonics Resonance Enhanced Active Photothermal Effects In Aluminum Nanoenergetics For Propulsion Applications, Jacques Abboud Aug 2013

Plasmonics Resonance Enhanced Active Photothermal Effects In Aluminum Nanoenergetics For Propulsion Applications, Jacques Abboud

Doctoral Dissertations

In this dissertation, aluminum nanoparticles (Al NPs) are shown capable to on-demand enhance and control the local photothermal energy deposition, both spatially and temporally, via active photothermal effects initiated by the localized surface plasmon resonance (LSPR) phenomenon, and amplified by the Al exothermal oxidation reactions. Experiments in dry and wet environments along with computational modeling of the photothermal process are very desirable for gaining fundamental understanding, ignition optimization and parameter exploration.

Combined phenomena of motion and ignition of Al NPs are explored first in this study. Both resulting from exposing a pile of the nanoenergetics in hand to a single …


Low Velocity Impact Tower Feasibility, Setup, And Impact Testing Of Carbon Fiber Reinforced Epoxy Thermoset And Peek Thermoplastic Matrix Composites, Brent Plehn Jun 2013

Low Velocity Impact Tower Feasibility, Setup, And Impact Testing Of Carbon Fiber Reinforced Epoxy Thermoset And Peek Thermoplastic Matrix Composites, Brent Plehn

Materials Engineering

A low velocity impact tower was donated to Cal Poly's Materials Engineering Department along with four fiber reinforced polymer matrix composites. The tower was set up in building 192 in the Mechanical Testing Laboratory. Improvements were made to the tower including adding velocity detection capabilities, making loose hardware inclusive, adding an extra tower arm for better consistency, adding a double jawed clamp for faster testing, and rerouting the tower's compressed air system to improve performance. A standard operating procedure was drafted, tested, and redrafted for impact testing composite panels. The four composite panels consisted of two quasi-isotropic 16 ply AS-1 …


Analyzing The Flexural Properties Of Self-Constructed Bamboo Laminates, Brett Dorren Jun 2013

Analyzing The Flexural Properties Of Self-Constructed Bamboo Laminates, Brett Dorren

Materials Engineering

Bamboo plies of 1/8" and 1/32" thicknesses were glued together to form multiple unidirectional and cross-ply laminates that measured 12" by 12". The thickness of each laminate was between 0.25" and 0.375". All laminates were pressed together with a Tetrahedron MTP-10 bench top precision press at 75°F and 1000 lbf for 40 minutes. Laminates were then cut with a band-saw into four 3" by 12" test specimens, 24 hours after pressing. Each test specimen was three-point bend tested to identify the modulus of rupture (MOR) and apparent bending stiffness. Three-point bend testing was also performed on laminates that were …


Evaluation Of High Phosphorus Electroless Nickel Platings To Protect Carbon Steel Heat Exchangers In Seawater Service, Nathan Brink Jun 2013

Evaluation Of High Phosphorus Electroless Nickel Platings To Protect Carbon Steel Heat Exchangers In Seawater Service, Nathan Brink

Materials Engineering

The purpose of this project was to determine the suitability of using a high phosphorus electroless nickel (HPEN) coating to prevent corrosion in carbon steel heat exchangers in seawater service. 1 in. x 4 in. samples were cut from ¼ in. SA-516-70 pressure vessel plate, pickled to remove mill scale, dressed with 300 grit sand paper and sent out for plating with 2 mils of HPEN. Due to a clerical error during plating, samples were plated to a significantly lesser extent than requested. Samples were plated with approximately 0.6 mils of HPEN versus the 2 mils requested, however this was …


Measuring The Mechanical Properties Of A Newly Developed Discontinuous Carbon Fiber And Epoxy Composite, Morgan Adams Jun 2013

Measuring The Mechanical Properties Of A Newly Developed Discontinuous Carbon Fiber And Epoxy Composite, Morgan Adams

Materials Engineering

Engineering firm Pratt & Miller have developed a new and previously untested carbon fiber/epoxy composite using a spray lay-up process similar to a process commonly used in fiberglass production. This new composite is made by using a pneumatic chop gun that simultaneously cuts the carbon fibers to a specific length and deposits the chopped fibers and resin onto surface of an exposed mold surface. The composite is then rolled down to flatten and better wet the fibers and then the whole mold is vacuum bagged at room temperature to cure. The flexural stiffness and flexural strength of the composite with …


Tensile Properties Of Adhesive Joints Between Alclad 2024-T3 Aluminum Sheets And Extruded 6061-T6511 Aluminum For Use In Ultralight Personal Aircraft, Kevin Jones Jun 2013

Tensile Properties Of Adhesive Joints Between Alclad 2024-T3 Aluminum Sheets And Extruded 6061-T6511 Aluminum For Use In Ultralight Personal Aircraft, Kevin Jones

Materials Engineering

Cold cure two-part epoxy adhesives were tested in aluminum joints to investigate their viability for use in an ultralight aircraft. The joints consisted of Alclad 2024-T3 aluminum sheets adhesively bonded to extruded 6061-T6511 aluminum, and are part of low-load-bearing members required to carry a minimum load of 175 lbs./ft. or 14.58 lbs./in. The Alclad 2024-T3 and 6061-T6511 aluminum were prepared by sanding with 80 grit abrasive paper, the surface was cleaned with acetone to remove surface contaminants, rinsed with distilled water, and dried using paper towels. Once the surface was prepared, the test coupons were assembled using one of the …


Design Of A Children’S Earth Science Exhibit For The Exploration Station In Grover Beach, California With An Emphasis On Fog Collection, Kathryn Thomas Jun 2013

Design Of A Children’S Earth Science Exhibit For The Exploration Station In Grover Beach, California With An Emphasis On Fog Collection, Kathryn Thomas

Materials Engineering

An outdoor earth science museum exhibit was designed for the Exploration Station in Grover Beach, California, and will use the harvesting methods of fog as a clean water resource to educate children. The design of the exhibit has two parts: a 1 m x 1 m static Standard Fog collector for long term fog collection which rises 2 m off the ground, and a mobile six-panel display consisting of six different materials and structures of meshes, all of which could potentially be used in a large scale fog collection setting. The six-panel portion will present the children with a hands-on …


Fluorescence Characterization Of Quantum Dots For Use As Biomarkers, Logan M. Grimes Jun 2013

Fluorescence Characterization Of Quantum Dots For Use As Biomarkers, Logan M. Grimes

Materials Engineering

Fluorescence profiles of quantum dots (QDs) were characterized to select the ideal QDs for encapsulation in phospholipids for use as biomarkers to selectively adhere to cancer cells. QDs were synthesized and extracted 0, 30, 60, and 90 seconds after precursor compounds were mixed. These extractions were isolated by extraction time. Portions from each vial were coated in a zinc sulfide shelling procedure, leaving at least half of the QD solution unshelled. These samples were characterized over four days to monitor fluctuations in fluorescence. This was done utilizing an Ocean Optics spectrometer in conjunction with Spectra Suite software. The central wavelength, …


Design And Construction Of A Simulated Evaporative Heat Exchanger For Testing The Mitigation Effects Of Pipe Coatings On Mineral Scale Deposition, Taylor J. Anderson Jun 2013

Design And Construction Of A Simulated Evaporative Heat Exchanger For Testing The Mitigation Effects Of Pipe Coatings On Mineral Scale Deposition, Taylor J. Anderson

Materials Engineering

The thermal efficiency of evaporative heat exchangers is diminishing due to mineral scale buildup on heat exchanger surfaces. A simulated evaporative heat exchanger was designed and constructed for testing the mitigation effects of polymer coatings on mineral scale deposition rates. The heat exchanger was designed to cool hot mud at 200°F using a cooling water supply with a calcium concentration of 1000 ppm. The system was constructed using 1.5-inch diameter polypropylene piping, a DIG Corporation drip irrigation system, a TotalPond 530 GPH pond pump, an Omega CSI32K miniature benchtop controller, Omega FWH321-020 high temperature heater tape, and fifteen copper pipe …


Application Of Quantum Dots Onto Glass Wafers As A Feasibility Test For The Spectral Down Conversion Of Uv Light For Solar Cells, Anthony Fong Jun 2013

Application Of Quantum Dots Onto Glass Wafers As A Feasibility Test For The Spectral Down Conversion Of Uv Light For Solar Cells, Anthony Fong

Materials Engineering

Quantum dots have the ability to convert high energy photons into multiple lower energy photons. Down conversion of such high energy photons from sources such as UV light can be beneficial for applications on solar cells which waste much of the energy in the form of thermalization. To test this theory, a solar cell was hooked up to an Amprobe Solar Analyzer and tests were run to compare power output with and without the presence of quantum dots. Additionally, quantum dots were spin coated onto a glass wafer to determine its adhesion ability. Spectrometer readings were taken of the wafer …


Thermally Insulating Coating For Steel Drill Pipe, Matthew Mccaffrey Jun 2013

Thermally Insulating Coating For Steel Drill Pipe, Matthew Mccaffrey

Materials Engineering

A 5/16 in thick, 6 in x 6 in steel plate was used as a simple analog to 4 inch grade “S” steel drill pipe. Ethylene tetraflouroethylene (ETFE) applied as a powder coating was selected as the desired thermally insulating coating because of its excellent chemical resistance, maximum service temperature of 300°C, its thermal conductivity of 0.238 W/m-K, and for its ability to be applied in thicknesses of up to 80 mils. A powder primer coat of approximately 2 mils was applied using a conventional corona electrostatic powder sprayer, and then the high build topcoat was applied directly over the …


Electrospun Plant Protein Scaffolds With Fibers Oriented Randomly And Evenly In Three-Dimensions For Soft Tissue Engineering Applications, Shaobo Cai Jun 2013

Electrospun Plant Protein Scaffolds With Fibers Oriented Randomly And Evenly In Three-Dimensions For Soft Tissue Engineering Applications, Shaobo Cai

Department of Textiles, Merchandising, and Fashion Design: Dissertations, Theses, and Student Research

In this work, electrospinnable and water stable soyprotein was extracted by using a reducing agent in mild alkaline condition, and novel 3D zein and 3D pure soyprotein electrospun scaffolds with three-dimensionally and randomly oriented fibers and large interconnected pores were successfully fabricated by reducing surface resistivity of materials. This unique structure is different from most electrospun scaffolds with fibers oriented mainly in one direction. The structure of novel 3D scaffolds could more closely mimic the 3D randomly oriented fibrous architectures in many native extracellular matrixes (ECM). Confocal laser scanning microscope shows that instead of becoming flattened cells when cultured in …


Structural And Kinetic Studies Of Structure I Gas Hydrates Via Low Temperature X-Ray Diffraction And High Resolution Neutron Diffraction, Susan Michelle Everett May 2013

Structural And Kinetic Studies Of Structure I Gas Hydrates Via Low Temperature X-Ray Diffraction And High Resolution Neutron Diffraction, Susan Michelle Everett

Doctoral Dissertations

Gas hydrates are materials of interest as sources for clean energy, carbon sequestration, greenhouse gas mitigation, and gas storage. This body of work presents two projects that each separately explore one aspect of the potential found in gas hydrates. Chapter 1 tackles the structural changes found to occur over the CO2 [carbon dioxide] - CH4 [methane] hydrate solid solution. The application here pertains to the sequestration of CO2 in natural gas hydrates found in permafrost regions and ocean floors. As CO2 is injected into the hydrate reservoir, CH4 is released and recovered for energy use. …


Analysis Of Bimetallic Adhesion And Interfacial Toughness Of Kinetic Metallization Coatings, Alec D. Guraydin May 2013

Analysis Of Bimetallic Adhesion And Interfacial Toughness Of Kinetic Metallization Coatings, Alec D. Guraydin

Master's Theses

Due to their ability to confer enhanced surface properties without compromising the properties of the substrate, coatings have become ubiquitous in heavy industrial applications for corrosion, wear, and thermal protection, among others. Kinetic Metallization (KM), a solid-state impact consolidation and coating process, is well-suited for depositing industrial coatings due to its versatility, low substrate heat input, and low cost. The ability of KM coatings to adhere to the substrate is determined by the quality of the interface. The purpose of this study is to develop a model to predict the interfacial quality of KM coatings using known coating and substrate …


Evaluation Of The Transient Thermal Performance Of A Graphite Foam/Phase Change Material Composite, Michael Paul Trammell May 2013

Evaluation Of The Transient Thermal Performance Of A Graphite Foam/Phase Change Material Composite, Michael Paul Trammell

Masters Theses

The thermal transient response of graphite foam infiltrated with paraffin wax as a thermal protection composite was investigated. Graphite foam is a rigid open-celled porous carbon material that exhibits high thermal conductivity along the ligaments. To increase the ability of graphite foam to store heat energy, it was infiltrated with a phase change material, paraffin wax. Filling the foam with a phase change material (PCM) creates a composite that transfers heat through an interconnected network of ligaments to a large surface area of PCM for absorption. Foams were made at various pressures to understand the effect of porosity, which also …


Micro-Mechanical Assessment Of The Local Plastic Strain Invoked During A Splined Mandrel Flow Forming Operation, Meysam Haghshenas Apr 2013

Micro-Mechanical Assessment Of The Local Plastic Strain Invoked During A Splined Mandrel Flow Forming Operation, Meysam Haghshenas

Electronic Thesis and Dissertation Repository

Splined Mandrel Flow Forming (SMFF) is a metal spinning operation that involves the application of high multiaxial compressive stress states to invoke large plastic flow in the work piece. This allows for essentially one-step fabrication of complex internally-splined shapes. In this research project, the equivalent plastic strain, invoked throughout bcc (1020 steel) and fcc (5052 and 6061 aluminum alloys, pure copper, and 70/30 brass) samples, that were made by SMFF, was measured. The objective of the research were to measure the to obtain data on the effect of microstructure and mechanical parameters on the flow formability of ductile bcc and …


Process-Structure Relationships Of Magnesium Alloys, Arindam Banerjee Apr 2013

Process-Structure Relationships Of Magnesium Alloys, Arindam Banerjee

Electronic Thesis and Dissertation Repository

This research study characterizes the effects of solidification conditions on the resulting microstructure of an AM60B magnesium alloy during the solidification cycle of the casting. Seventeen control points are chosen from different sections of an instrument panel beam casting and its centerline coordinates are located. These control points locations are then used by Meridian Lightweight Technology Inc. to run a simulation in a MAGMASoft casting software to obtain temperature-time specific data.

An exact analytical solution to the Stefan problem is used to compute the one dimensional heat transfer for a section of the casting and to calculate its temperature distribution …


Metamaterial Structure Design Optimization: A Study Of The Cylindrical Cloak, Jason V. Paul Mar 2013

Metamaterial Structure Design Optimization: A Study Of The Cylindrical Cloak, Jason V. Paul

Theses and Dissertations

Previously, Transformational Optics (TO) has been used as a foundation for designing cylindrical cloaks. The TO method uses a coordinate transform to dictate an anisotropic material parameter gradient in a cylinder coating that guides waves around the cylinder to reduce the Radar Cross Section (RCS). The problem is that the material parameters required for the TO cloak are not physically realizable and thus must be approximated. This problem is compounded by the fact that any approximation deviates from the ideal design and will allow fields to penetrate the cloak layer and interact with the object to be cloaked. Since the …


Structural Tailoring Of Nanoporous Metals And Study Of Their Mechanical Behavior, Lei Wang Jan 2013

Structural Tailoring Of Nanoporous Metals And Study Of Their Mechanical Behavior, Lei Wang

Theses and Dissertations--Chemical and Materials Engineering

Nanoporous (np) metals and alloys are the subject of increasing research attention due to their high surface-area-to-volume ratio. Numerous methods exist to create np metals, with dealloying being a common approach. By dissolving one or more elements from certain alloy systems, porous structure can be generated. Utilizing this method, multiple np metals, including np-Ni, np-Ir, and np-Au were created. By carefully adjusting precursor type and dealloying conditions for each system, nanoporous Ni/Ir/Au with different morphologies and even controllable ligament/pore size were achieved.

The mechanical behavior of porous materials is related to their fully dense counterparts by scaling equations. Established scaling …