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- Creators: Barrett, The Honors College
Description
With renewable energy on the rise, researchers have turned their funding and their focus towards new solar cell technologies, and perovskites are a major source of interest. This class of materials is particularly interesting due to their quick, simple synthesis as well as their physical and electrical superiority when compared to current silicon-based solar cells. Through this thesis, we will explore the synthesis of various types of perovskites and their subsequent characterization, which includes optical microscopy, photoluminescence spectroscopy, Raman microscopy, and X-ray diffraction. Analyzing two different perovskites both before and after a two-week period of storage revealed that while synthesis is indeed experiment-friendly, these materials have a concerning lack of stability even in ideal conditions.
ContributorsBuzas, Benjamin Joseph (Author) / Tongay, Sefaattin (Thesis director) / Muhich, Christopher (Committee member) / Materials Science and Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Hyperspectral imaging is a novel technology which allows for the collection of reflectance spectra of a sample in-situ and at a distance. A rapidly developing technology, hyperspectral imaging has been of particular interest in the field of art characterization, authentication, and conservation as it avoids the pitfalls of traditional characterization techniques and allows for the rapid and wide collection of data never before possible. It is hypothesized that by combining the power of hyperspectral imaging with machine learning, a new framework for the in-situ and automated characterization and authentication of artworks can be developed. This project, using the CMYK set of inks, began the preliminary development of such a framework. It was found that hyperspectral imaging and machine learning as a combination show significant potential as an avenue for art authentication, though further progress and research is needed to match the reliability of status quo techniques.
ContributorsChowdhury, Tanzil Aziz (Author) / Newman, Nathan (Thesis director) / Tongay, Sefaattin (Committee member) / School of Politics and Global Studies (Contributor) / Materials Science and Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Throughout history, African-Americans have had to fight for their civil rights. There were many ways used to voice their opinions and advance the civil rights movement, including protests and marches. One very effective method was through music and the creation of jazz. Louis Armstrong was an innovator and major influence of jazz. His abilities as an artist were recognized by society, above his political position or class status.
The topic of my thesis is Louis Armstrong and his influence on society and the Civil Rights Movement. The intent is to demonstrate how Louis Armstrong aided the Civil Rights Movement by using his music to promote social justice and racial equality. The focus will be on the context of African-Americans, their social status, and rights from the early 1900s to the mid-1900s. I will connect this to important events in that time such as the fight against Jim Crow Laws and how Louis Armstrong played a role in ending segregation. He accomplished this by pushing the movement forward through speeches, fund-raising events, and his innovation of jazz. Armstrong’s gift was a form of swing jazz that advanced improvisation and emotion of music.
He was criticized for playing to segregated audiences and was thought to keep offensive stereotypes alive. However, Louis Armstrong battled against these conspiracies by performing fund-raising events and through public political stances against the oppression of African-Americans. As an example, he was outspoken about his disapproval of government and the public for their treatment of the nine African-American students enrolled at Little Rock. This resulted in the first time the school would be unsegregated between whites and blacks. Louis Armstrong worked hard in the fight against segregation and used his mastery of jazz to advance the civil rights movement. Finally, I will make a proposal as to how society can learn from Louis Armstrong and how to inspire new innovative forms of positively influencing society to help the less fortunate.
The topic of my thesis is Louis Armstrong and his influence on society and the Civil Rights Movement. The intent is to demonstrate how Louis Armstrong aided the Civil Rights Movement by using his music to promote social justice and racial equality. The focus will be on the context of African-Americans, their social status, and rights from the early 1900s to the mid-1900s. I will connect this to important events in that time such as the fight against Jim Crow Laws and how Louis Armstrong played a role in ending segregation. He accomplished this by pushing the movement forward through speeches, fund-raising events, and his innovation of jazz. Armstrong’s gift was a form of swing jazz that advanced improvisation and emotion of music.
He was criticized for playing to segregated audiences and was thought to keep offensive stereotypes alive. However, Louis Armstrong battled against these conspiracies by performing fund-raising events and through public political stances against the oppression of African-Americans. As an example, he was outspoken about his disapproval of government and the public for their treatment of the nine African-American students enrolled at Little Rock. This resulted in the first time the school would be unsegregated between whites and blacks. Louis Armstrong worked hard in the fight against segregation and used his mastery of jazz to advance the civil rights movement. Finally, I will make a proposal as to how society can learn from Louis Armstrong and how to inspire new innovative forms of positively influencing society to help the less fortunate.
ContributorsSchmerler, Cameron (Author) / Wells, Christopher (Thesis director) / Feisst, Sabine (Committee member) / Department of Management and Entrepreneurship (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
This paper investigates Surface Mechanical Attrition Treatment (SMAT) and the influence of treatment temperature and initial sample surface finish on the corrosion resistance of 7075-T651 aluminum alloy. Ambient SMAT was performed on AA7075 samples polished to 80-grit initial surface roughness. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests were used to characterize the corrosion behavior of samples before and after SMAT. Electrochemical tests indicated an improved corrosion resistance after application of SMAT process. The observed improvements in corrosion properties are potentially due to microstructural changes in the material surface induced by SMAT which encouraged the formation of a passive oxide layer. Further testing and research are required to understand the corrosion related effects of cryogenic SMAT and initial-surface finish as the COVID-19 pandemic inhibited experimentation plans.
ContributorsDeorio, Jordan Anthony (Author) / Solanki, Kiran (Thesis director) / Rajagopalan, Jagannathan (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
With this thesis, I have set out to answer two fundamental questions within music: does music mean anything, and should music mean anything? In answering those questions, I also set out to create a creative project that would implement these ideas: an original concept album of music that is programmatic in nature and incorporates motivic composition, jazz improvisation, lyrics, extra-musical audio and more all in the service of telling a narrative, a story, through music. I have done research into understanding music as a language, finding that this language is primarily communicative and recreational, rather than representational, of meaning. As well, I discuss the various different ways that music composers from Wagner to Williams have created narrative meaning in their works, using examples of leitmotif and other devices, as well as tracing the contextual associations of meaning that occurs when music is perceived in certain contexts. Furthermore, I discuss the dialogue between absolute and programmatic music, and also talk about the role of jazz improvisation in adding meaning to works.
For the second part of my thesis I talk about how I came to create the creative project aspect. I discuss how and why I designed the narrative that I did, and also analyzed the music I have created to illustrate how I implemented the various methods of musical storytelling that I detail in the first part of the paper. Lastly, I discuss my plans for publication and release of the creative project.
The third part of this thesis is a sample of the creative project. There is a version of the narrative that goes along with the creative project, as well as one of the eight pieces of original music on the creative project, entitled Journey.
Overall, I found that music does have meaning, it is just meaning that society ascribes to it based off of artistic intent and context, and as to whether music should mean anything, I believe that this is a question best left to be answered on an individual basis. Music can be whatever it wants to be.
For the second part of my thesis I talk about how I came to create the creative project aspect. I discuss how and why I designed the narrative that I did, and also analyzed the music I have created to illustrate how I implemented the various methods of musical storytelling that I detail in the first part of the paper. Lastly, I discuss my plans for publication and release of the creative project.
The third part of this thesis is a sample of the creative project. There is a version of the narrative that goes along with the creative project, as well as one of the eight pieces of original music on the creative project, entitled Journey.
Overall, I found that music does have meaning, it is just meaning that society ascribes to it based off of artistic intent and context, and as to whether music should mean anything, I believe that this is a question best left to be answered on an individual basis. Music can be whatever it wants to be.
ContributorsPrice, Alexander (Author) / Gilfillan, Daniel (Thesis director) / Kocour, Michael (Committee member) / Libman, Jeffrey (Committee member) / Department of English (Contributor) / School of Music (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Non-Destructive Testing (NDT) is integral to preserving the structural health of materials. Techniques that fall under the NDT category are able to evaluate integrity and condition of a material without permanently altering any property of the material. Additionally, they can typically be used while the material is in active use instead of needing downtime for inspection.
The two general categories of structural health monitoring (SHM) systems include passive and active monitoring. Active SHM systems utilize an input of energy to monitor the health of a structure (such as sound waves in ultrasonics), while passive systems do not. As such, passive SHM tends to be more desirable. A system could be permanently fixed to a critical location, passively accepting signals until it records a damage event, then localize and characterize the damage. This is the goal of acoustic emissions testing.
When certain types of damage occur, such as matrix cracking or delamination in composites, the corresponding release of energy creates sound waves, or acoustic emissions, that propagate through the material. Audio sensors fixed to the surface can pick up data from both the time and frequency domains of the wave. With proper data analysis, a time of arrival (TOA) can be calculated for each sensor allowing for localization of the damage event. The frequency data can be used to characterize the damage.
In traditional acoustic emissions testing, the TOA combined with wave velocity and information about signal attenuation in the material is used to localize events. However, in instances of complex geometries or anisotropic materials (such as carbon fibre composites), velocity and attenuation can vary wildly based on the direction of interest. In these cases, localization can be based off of the time of arrival distances for each sensor pair. This technique is called Delta T mapping, and is the main focus of this study.
The two general categories of structural health monitoring (SHM) systems include passive and active monitoring. Active SHM systems utilize an input of energy to monitor the health of a structure (such as sound waves in ultrasonics), while passive systems do not. As such, passive SHM tends to be more desirable. A system could be permanently fixed to a critical location, passively accepting signals until it records a damage event, then localize and characterize the damage. This is the goal of acoustic emissions testing.
When certain types of damage occur, such as matrix cracking or delamination in composites, the corresponding release of energy creates sound waves, or acoustic emissions, that propagate through the material. Audio sensors fixed to the surface can pick up data from both the time and frequency domains of the wave. With proper data analysis, a time of arrival (TOA) can be calculated for each sensor allowing for localization of the damage event. The frequency data can be used to characterize the damage.
In traditional acoustic emissions testing, the TOA combined with wave velocity and information about signal attenuation in the material is used to localize events. However, in instances of complex geometries or anisotropic materials (such as carbon fibre composites), velocity and attenuation can vary wildly based on the direction of interest. In these cases, localization can be based off of the time of arrival distances for each sensor pair. This technique is called Delta T mapping, and is the main focus of this study.
ContributorsBriggs, Nathaniel (Author) / Chattopadhyay, Aditi (Thesis director) / Papandreou-Suppappola, Antonia (Committee member) / Skinner, Travis (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Titanium dioxide is an essential material under research for energy and environmental applications, chiefly through its photocatalytic properties. These properties allow it to be used for water-splitting, detoxification, and photovoltaics, in addition to its conventional uses in pigmentation and sunscreen. Titanium dioxide exists in several polymorphic structures, of which the most common are rutile and anatase. We focused on anatase for the purposes of this research, due to its promising results for hydrolysis.
Anatase exists often in its reduced form (TiO2-x), enabling it to perform redox reactions through the absorption and release of oxygen into/from the crystal lattice. These processes result in structural changes, induced by defects in the material, which can theoretically be observed using advanced characterization methods. In situ electron microscopy is one of such methods, and can provide a window into these structural changes. However, in order to interpret the structural evolution caused by defects in materials, it is often necessary and pertinent to use atomistic simulations to compare the experimental images with models.
In this thesis project, we modeled the defect structures in anatase, around oxygen vacancies and at surfaces, using molecular dynamics, benchmarked with density functional theory. Using a “reactive” forcefield designed for the simulation of interactions between anatase and water that can model and treat bonding through the use of bond orders, different vacancy structures were analyzed and simulated. To compare these theoretical, generated models with experimental data, the “multislice approach” to TEM image simulation was used. We investigated a series of different vacancy configurations and surfaces and generated fingerprints for comparison with TEM experiments. This comparison demonstrated a proof of concept for a technique suggesting the possibility for the identification of oxygen vacancy structures directly from TEM images. This research aims to improve our atomic-level understanding of oxide materials, by providing a methodology for the analysis of vacancy formation from very subtle phenomena in TEM images.
Anatase exists often in its reduced form (TiO2-x), enabling it to perform redox reactions through the absorption and release of oxygen into/from the crystal lattice. These processes result in structural changes, induced by defects in the material, which can theoretically be observed using advanced characterization methods. In situ electron microscopy is one of such methods, and can provide a window into these structural changes. However, in order to interpret the structural evolution caused by defects in materials, it is often necessary and pertinent to use atomistic simulations to compare the experimental images with models.
In this thesis project, we modeled the defect structures in anatase, around oxygen vacancies and at surfaces, using molecular dynamics, benchmarked with density functional theory. Using a “reactive” forcefield designed for the simulation of interactions between anatase and water that can model and treat bonding through the use of bond orders, different vacancy structures were analyzed and simulated. To compare these theoretical, generated models with experimental data, the “multislice approach” to TEM image simulation was used. We investigated a series of different vacancy configurations and surfaces and generated fingerprints for comparison with TEM experiments. This comparison demonstrated a proof of concept for a technique suggesting the possibility for the identification of oxygen vacancy structures directly from TEM images. This research aims to improve our atomic-level understanding of oxide materials, by providing a methodology for the analysis of vacancy formation from very subtle phenomena in TEM images.
ContributorsShindel, Benjamin Noam (Author) / Crozier, Peter (Thesis director) / Anwar, Shahriar (Committee member) / Singh, Arunima (Committee member) / Materials Science and Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The possibility of creating inorganic/organic hybrid materials has yet to be fully explored within geopolymer research. Using PDMS as an organic precursor, the surface of sodium and potassium geopolymers of varying precursor composition were functionalized with degraded PDMS oligomers. Both types of geopolymer yielded hydrophobic materials with BET surface area of 0.6475 m2/g and 4.342 m2/g for sodium and potassium geopolymer, respectively. Each respective material also had an oil capacity of 74.75 ± 4.06 weight% and 134.19 ± 4.89 weight%. X-ray diffraction analysis demonstrated that the PDMS functionalized sodium geopolymers had similar crystal structures that matched references for zeolite A and sodalite. The potassium geopolymers were amorphous, but showed consistency in diffraction patterns across different compositions.
ContributorsMaurer, Matthew (Author) / Seo, Don (Thesis director) / Ciota, David (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor)
Created2022-05