Physical Sciences and Mathematics Commons^™

Machine Learning Prediction Of Hea Properties, Nicholas J. Beaver, Nathaniel Melisso, Travis Murphy

College of Engineering Summer Undergraduate Research Program

High-entropy alloys (HEA) are a very new development in the field of metallurgical materials. They are made up of multiple principle atoms unlike traditional alloys, which contributes to their high configurational entropy. The microstructure and properties of HEAs are are not well predicted with the models developed for more common engineering alloys, and there is not enough data available on HEAs to fully represent the complex behavior of these alloys. To that end, we explore how the use of machine learning models can be used to model the complex, high dimensional behavior in the HEA composition space. Based on our …

Covalent Adaptable Networks For Wood Coatings, Jachin Boaz Clarke

Materials Engineering

Wood swells and shrinks causing problems with seasonal humidity. Applying thick coatings of reactive finishes based on cross-linked polyurethane, epoxy, or polyesters can slow moisture-vapor exchange. However, the use of thick coatings leads to cracking and crazing sooner than thin finishes. This research proposes the addition of 3.3 mol % triazabicyclodecene, a conventionally used covalent adaptable network catalyst, in a commercially available polyester-based wood coating. The self-healing of the wood coating is tested using DMA stress relaxation and compression molding. The result from DMA renders inconclusive and compression molding indicates the novel wood coating oxidizes at elevated temperatures. The wood …

Exploring The Potential Of Pavegen’S Kinetic Energy Generating Floor For Sustainable Energy Solutions: A Proposal For Cal Poly Slo, Brandon J. Cuneo

Construction Management

This paper proposes the installation of Pavegen's kinetic energy generating floors at Cal Poly’s campus as a sustainable energy solution. Pavegen has developed a pioneering technology that converts footsteps into clean and renewable energy. The versatility of these floors is demonstrated through successful implementations in various settings, such as transportation hubs and public spaces, generating power from foot traffic. Collaborations with Schneider Electric, installation at Dupont Circle, and integration at Heathrow Airport showcase the potential for sustainable urban infrastructure. This paper outlines research conducted on Pavegen and similar solutions, including communication with company representatives and examining proposed installation locations at …

Precious Plastics - Plastic Brick Machine Fabrication, Timothy Ukaobasi Kanu, Evi Paraskevi Troulis

Architectural Engineering

The goal of this research is to determine the structural parameters of the recycled plastic polypropylene when molded into bricks resembling CMU blocks. To accomplish this, three mechanisms had to be assembled: the shredder, the injector, and the 1x1 mold. A tensile and compression test were to be performed on the plastic brick, and the values would be used to compare the tensile and compressive strength of PP plastic bricks, as well as their modulus of elasticity and stress vs. Strain performance. These values would be analyzed to determine whether it would be feasible to build an entire plastic wall. …

Building Structures From Mycelium, Noah M. Brown

Physics

The purpose of this project was to develop a method for creating bricks from mycelium and agricultural waste. The bulk of the research happened in two parts, the first part being a period in which different substrates, strains, and methods were used build the bricks. This research took place in San Luis Obispo and was aided by a group of students in PSC392 under Dr. Pete Schwartz in early 2022. After developing a method for constructing these bricks, the research was moved to St. Thomas, Jamaica, in collaboration with an ecovillage called The Source Farm from July to September. The …

Developing Positive Thermal Coefficient (Ptc) Heaters For Solar Electric Cooking, Katarina Ivana Brekalo, Andrew Shepherd

Physics

Positive Thermal Coefficients, PTCs, are materials that abruptly change in resistance in response to changes in temperature. The purpose of this experiment is to explore the viability of using the switching type ceramic PTC thermistor as a replacement for current resistive heaters. These types of PTCs have a nonlinear change in resistance with increases in temperature. This device will be used as a temperature-controlling heating element intended to power an Insulated Solar Electric Cooker (ISEC). The ISEC is designed to cook meals throughout the day for impacted communities as an alternative cooking method that doesn’t require biofuel as an energy …

Pressure Driven Desalination Membranes: Lyotropic Liquid Crystals Containing Single Walled Carbon, Matteo A. Del Giudice, Samantha Castillo Merigold

Materials Engineering

This project presents a potential alternative desalination technique that utilizes the ion rejection properties of single walled carbon nanotubes dispersed in a lyotropic liquid crystal (LLC) matrix. Previous research has pointed to the polymerizable surfactant methacryloxy ethyl hexadecyl dimethyl ammonium bromide (C16MA) having capabilities of filtering molecular components smaller than a nanometer, when oriented in cylindrical micelles. SWCNTs were dispersed in deionized water by probe sonication and addition of surfactant cetyltrimethylammonium bromide (CTAB) due to SWCNTs’ hydrophobic properties. Membranes were produced containing 55wt% C16MA, 37wt% DI water, 0.1wt% with respect to the monomer (WRM) SWCNTs, 1.9 wt% WRM 2,2-dimethoxy-2-phenylacetophenone (photointiator), …

Comparing The Environmental Impacts Of Using Mass Timber And Structural Steel, Khang Hoang Nguyen, Steelee Knight Morgan

Construction Management

Although mass timber has seen a gradual rise in demand in the past, there has been a lack of extensive research on the environmental impacts of using mass timber as a primary structural framing material. This paper compares structural steel, and mass timber’s total embodied carbon emissions. Accurate estimates were made using plans and specs for different projects retrieved from semi-structured interviews. The estimates were input through the EC3 Calculator to provide extensive total carbon emissions measurements between each construction material. Using structural steel framing increased the project’s overall environmental impact by roughly 84% compared to using mass timber. The …

Non-Toxic Soil Thickeners For Reducing Mudslide Intensity, Mitchell William Jensen

Materials Engineering

This project was intended to be a continuation of senior project work done last year by a group consisting of two Materials Engineering students and a Soil Science student. Their report was crucial in identifying a range of food thickeners that could be capable of performing in the mud thickening application. All thickeners that were chosen both this year and last year are biocompatible, to alleviate some toxicity concerns. The food thickeners all belong to a class of compounds known as colloids. Since water is the fluid being thickened, these compounds are more accurately referred to as hydrocolloids. Hydrocolloids are …

Implementation Of Multivariate Artificial Neural Networks Coupled With Genetic Algorithms For The Multi-Objective Property Prediction And Optimization Of Emulsion Polymers, David Chisholm

Master's Theses

Machine learning has been gaining popularity over the past few decades as computers have become more advanced. On a fundamental level, machine learning consists of the use of computerized statistical methods to analyze data and discover trends that may not have been obvious or otherwise observable previously. These trends can then be used to make predictions on new data and explore entirely new design spaces. Methods vary from simple linear regression to highly complex neural networks, but the end goal is similar. The application of these methods to material property prediction and new material discovery has been of high interest …

Nano Fab Lab 63, Brian K. Deemer, Josh Clemons, Nick Brodine, Delaney Fitzsimmons

Mechanical Engineering

Lawrence Livermore National Laboratories (LLNL) has several steps in the production process for ceramic nanofiber tubes that they would like to improve - electrospinning, cutting, rolling, sealing and heat treating. We undertook the challenge to deliver LLNL with a semi-automated process that efficiently integrates the steps of cutting, rolling, and sealing to save time and improve control over end dimensions. In this document, we discuss the technical background of the manufacturing steps currently followed to create nanofiber tubes, identify which steps are incorporated in our prototype and explain how they will interface with one another, define the design requirements, present …

Usage Of Fomblin Y To Improve Water Repellence Of Surface Coatings, Shawn Pj Kirby, Jeffrey Alston, Andrew Guenthner

STAR Program Research Presentations

Fluoro-Decyl POSS (FDP) has shown strong potential as a water repellant surface coating. Additionally, Fomblin is a solvent believed to have the ability to control the crystallization of POSS compounds on surfaces. Controlling the crystallization is key to improving water repelling abilities of surfaces. Thus, dip coating FDP and Fomblin onto surfaces is being investigated for water repulsion, mechanical stability, and deposition feasibility. First, temperature dependence of solubility of Fluoro-Decyl POSS in Fomblin was tested using Dynamic Light Scattering. Relative water repelling abilities of different coatings were determined by measuring contact angle of surfaces with water. Coatings with and without …

Comparative Solubility Of Poss Compounds In Fomblin Y, Shawn Pj Kirby, Jeffrey Alston, Andrew Guenthner

STAR Program Research Presentations

Fluoro-Decyl POSS (FDP) has shown strong potential as a water repellant surface coating. Additionally, Fomblin is a solvent believed to have the ability to control the crystallization of POSS compounds on surfaces. Controlling the crystallization is key to improving water repelling abilities of surfaces. Thus, dip coating FDP and Fomblin onto surfaces is being investigated for water repulsion, mechanical stability, and deposition feasibility. However, in order for this to be successful, POSS must be soluble in Fomblin. Temperature dependence of solubility of Fluoro-Hexyl, Fluoro-Octyl, Fluoro-Decyl POSS in Fomblin was tested using Dynamic Light Scattering. The values were compared, and it …

Gc Verification Of The Spacecraft Atmosphere Monitor, Jessica S. Castro, Richard D. Kidd, Jeffrey D. Hein

STAR Program Research Presentations

International Space Station crew members face the unique challenge of maintaining air quality due to the volatile organic compounds (VOCs) that have the potential to accumulate at unsafe levels. The Spacecraft Atmosphere Monitor (SAM) is a miniature gas chromatograph/mass spectrometer (GCMS) designed to measure major constituents (such as N₂, O₂ and CO₂) and trace VOCs within the cabin of the spacecraft. The gas chromatograph is responsible for separating the sample into its components in order to be characterized. The oven of the gas chromatograph must reach a temperature of 150°C in order to heat constituents …

Metals Additive Manufacturing Powder Aging Characterization, Thomas Russell Lovejoy, Nicholas Karl Muetterties, David Takeo Otsu

Mechanical Engineering

The metallic additive manufacturing process known as selective laser melting requires highly spherical, normally distributed powder with diameters in the range of 10 to 50 microns. Previous observations have shown a degradation in powder quality over time, resulting in unwanted characteristics in the final printed parts. 21-6-9 stainless steel powder was used to fabricate test parts, with leftover powder recycled back into the machine. Powder samples and test specimens were characterized to observe changes across build cycles. Few changes were observed in the physical and mechanical properties of the specimens, however, there were indications of chemical changes across cycles. Potential …

Wet Chemical Synthesis And Characterization Of Nanomaterials For Solar Cell Applications, Krystle N. Sy, Ramprasad Gandhiraman, Jessica E. Koehne

STAR Program Research Presentations

During long term space missions, it is necessary to have a reliable source of energy. Solar cells are an easy and reliable way to convert energy from the sun to electrical energy. NASA has used solar cells manufactured on Earth as an energy source for many of its missions. In order to develop technologies that will enable high efficiency solar cells, we are synthesizing nanostructured materials. A range of nanostructured materials, such as titanium dioxide nanowires, nickel nanoparticles, copper nanoparticles, and silver nanoparticles/nanowires, are synthesized. In this work, we are reporting on the synthesis of these nanomaterials and the electron …

Effect Of Surfactant Architecture On Conformational Transitions Of Conjugated Polyelectrolytes, Greg A. Braggin

Master's Theses

Water soluble conjugated polyelectrolytes (CPEs), which fall under the category of conductive polymers, possess numerous advantages over other conductive materials for the fabrication of electronic devices. Namely, the processing of water soluble conjugated polyelectrolytes into thin film electronic devices is much less costly as compared to the processing of inorganic materials. Moreover, the handling of conjugated polyelectrolytes can be performed in a much more environmentally friendly manner than in the processing of other conjugated polymers because conjugated polyelectrolytes are water soluble, whereas other polymers will only dissolve in toxic organic solvents. The processing of electronic devices containing inorganic constituents such …

Characterization Of Samples For Optimization Of Infrared Stray Light Coatings, Carey L. Baxter, Rebecca Salvemini, Zaheer A. Ali, Patrick Waddell, Greg Perryman, Bob Thompson

STAR Program Research Presentations

NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) is a converted 747SP that houses a 2.5 m telescope that observes the sky through an opening in the side of the aircraft. Because it flies at altitudes up to 45,000 feet, SOFIA gets 99.99% transmission in the infrared. Multiple science instruments mount one at a time on the telescope to interpret infrared and visible light from target sources. Ball Infrared Black (BIRB) currently coats everything that the optics sees inside the telescope assembly (TA) cavity in order to eliminate noise from the glow of background sky, aircraft exhaust, and other sources. A …

P3ht:Pcpdtbt:Pcbm Multi- Polymer Single Layer Solar Cells, Ted Andreas

Physics

OPV efficiencies are limited by their narrow absorption; rather than using tandem architecture to overcome this obstacle, our group combined P3HT and PCPDTBT into a single layer BHJ solar cell that achieved 2.0% PCE. This is 33% higher than the pure P3HT control from this group, proving that multi-polymer solar cells have the potential to outperform their single-polymer components.

Commissioning Of The Asta Laser Lab With Uv Pulse Length Characterization, Daniel Kelley, Jeff Corbett

STAR Program Research Presentations

The Linac Coherent Light Source (LCLS) at SLAC depends on a photocathode electron gun to provide the linear accelerator with the raw material – electrons – used for making X-ray laser pulses. The photocathode used in the LCLS Injector is a clean copper plate in high vacuum. When the cathode is struck with high energy UV light, electrons are liberated from its surface and then accelerated down the linac with radio-frequency electric fields. These fast-moving bunches of electrons are directed through an undulator magnet to radiate X-ray light.

Although scientists have been using photocathode techniques at SLAC for 25 years, …

The Effect Of Polarization And Ingan Quantum Well Shape In Multiple Quantum Well Light Emitting Diode Heterostructures, Patrick M. Mcbride

Master's Theses

Previous research in InGaN/GaN light emitting diodes (LEDs) employing semi-classical drift-diffusion models has used reduced polarization constants without much physical explanantion. This paper investigates possible physical explanations for this effective polarization reduction in InGaN LEDs through the use of the simulation software SiLENSe. One major problem of current LED simulations is the assumption of perfectly discrete transitions between the quantum well (QW) and blocking layers when experiments have shown this to not be the case. The In concentration profile within InGaN multiple quantum well (MQW) devices shows much smoother and delayed transitions indicative of indium diffusion and drift during …

Blunt Impact Performance Evaluation Of Helmet Lining Systems For Military And Recreational Use, Jaclyn Siniora, Ryan Taylor, Darren Suey

Industrial Technology and Packaging

With the increasing problem in collegiate athletes experiencing injuries to the brain, different helmet liners where put to the test to see which liner provided athletes the greatest protection under specific conditions.

This senior project evaluates five different liners in football helmets. Each of the helmet liners were tested at three different temperatures: hot, cold, and ambient. Each helmet had seven different impact locations which were put to the test. The project was designed to be used to test ACH military combat liners as well. Due to shipping bottle necks the ACH combat liners have been left to future Cal …

Multipolymer Interactions In Bulk Heterojunction Photovoltaic Devices, Grant Olson

Physics

Multipolymer photovoltaics, single layer devices made up of multiple photoactive polymers, can create organic photovoltaics (OPVs) with a wider spectral response than single polymer systems without the difficult fabrication of a tandem. Our group has successfully created multipolymer solar devices with 2% power conversion efficiency. We have analyzed the optical and electrical properties of these devices, and found that it may be possible for polymers to assist each other with charge extraction, though combining polymers disrupts single polymer crystallinity.

Effect Of Au Content On Microstructural Evolution Of Snagcu Solder Joints That Undergo Isothermal Aging And Reliability Testing, Patrick J. Hyland

Master's Theses

Electronics, especially, printed circuit boards (PCBs) are a widespread technology. Metal coatings or “surface finishes” are often added to PCB board pads and component leads during manufacturing to improve their performance. Electroplated nickel/gold over copper is a popular surface finish for printed circuit boards and component leads. The presence of gold in solder joints, however, is known to have detrimental effects referred to as gold embrittlement. It is generally understood that tin-lead solder joints with less than 3 weight percent (wt%) of gold will not experience reliability issues. The acceptable level of gold in lead-free solder joints, however, is less …

Morphology Changes In Pcpdtbt:Pcbm And P3ht:Pcpdtbt:Pcbm And Its Effect On Polymer Solar Cell Performance, Galen David Cauble

Physics

Polymer solar cell morphology is sensitive to both heat and time. By thermally annealing polymer solar cells the morphology of the devices can be altered causing immediate changes in device performance. Blending PCPDTBT:PCBM with P3HT:PCPDTBT combines the absorption characteristics of each to create a more even absorption spectrum. Subjecting PCPDTBT:PCBM, and P3HT:PCPDTBT:PCBM polymer solar cells to thermal annealing as well as recording device performance through time has shown that P3HT:PCPDTBT:PCBM devices react positively to thermal annealing (increasing from 0.8% to 1.4%) while PCPDTBT:PCBM devices have varied reactions. Furthermore, the P3HT:PCPDTBT:PCBM devices have achieved efficiencies of 1.6% in AM 1.5 compared …

Quantitative Characterization Of Microstructure Features For 1st Generation Advanced High Strength Steels, Margarita Vidrio, Ellen Liu, Donsheng Li, Kyoo Sil Choi, Xin Sun

STAR Program Research Presentations

The role of Advanced High Strength Steels (AHSS) in the automotive industry is important because of its affordability and excellent mechanical properties. The 1st generation of AHSS achieves its preferred combination of strength and ductility by embedding harder martensite grains into softer ferritic matrix. Ductility and strength of these steels are important to safety, formability, application, and life. However, a noticeable degree of inconsistent forming behaviors has been observed in the 1st generation AHSS in production, which seems to be related to the microstructure-level inhomogeneity. The objective of this project is to grain fundamental understandings on how different microstructure level …

Artificial Muscle Project: Process Development Of Polydimethyl Siloxane Thin Films For Use In Dielectric Electroactive Polymer Artificial Muscle Actuators, Vincent J. Gayotin, Richard W. Morrison, Paul A. Preisser

Materials Engineering

An artificial muscle design was created founded on the principles of a dielectric electroactive polymer (DEAP), which is fundamentally similar to a capacitor. A polydimethyl siloxane (PDMS)-based elastomer, Sylgard 184 from Dow Corning, was chosen for the design and spun coat onto polystyrene (PS) Petri dishes at varying speeds to create a thin film, using speeds of 2000 rpm, 3000 rpm, 4000 rpm, 5000 rpm, and 6000 rpm. The film thicknesses were measured optically through use of a microscope with coupled computer imaging software to generate a characteristic curve of film thickness to spin speed, achieving a minimum film thickness …

The Effects Of Cure Schedule On Properties Of Glass-Fiber Reinforced Epoxy Matrix Composites, Trevor J. Lee

Materials Engineering

Two different two-component resin systems were cured, via Differential Scanning Calorimetry, for the times recommended by their respective manufacturers. The resin cure schedules were designed to simulate typical and attainable processing conditions; they were cured at 120°F, 140°F, and 160°F, and in-mold post-cured at 200°F, 230°F, and 260°F. The resulting scans were then compared to a baseline cure for each resin system, consisting of two heating-cooling cycles at a constant rate of temperature change. These baseline cures were then used to determine the percent cure of each sample and the shift in glass transition temperature between the baseline cure and …

Optimization Of P3ht-Pcbm Polymer Solar Cells Through Device Simulation And Manufacturing, James Boom

Computer Engineering

Given a good model and implementation of that model, computer simulation can be used to reduce the time and material costs of research. To this end I worked with other students to manufacture, test and simulate the single layer P3HT-PCBM solar cell. Using the data collected from this project, future work can then be done with the project's simulator to further optimize these types of solar cell devices.