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The electrode-electrolyte interface in electrochemical environments involves the understanding of complex processes relevant for all electrochemical applications. Some of these processes include electronic structure, charge storage, charge transfer, solvent dynamics and structure and surface adsorption. In order to engineer electrochemical systems, no matter the function, requires fundamental intuition of all

The electrode-electrolyte interface in electrochemical environments involves the understanding of complex processes relevant for all electrochemical applications. Some of these processes include electronic structure, charge storage, charge transfer, solvent dynamics and structure and surface adsorption. In order to engineer electrochemical systems, no matter the function, requires fundamental intuition of all the processes at the interface. The following work presents different systems in which the electrode-electrolyte interface is highly important. The first is a charge storage electrode utilizing percolation theory to develop an electrode architecture producing high capacities. This is followed by Zn deposition in an ionic liquid in which the deposition morphology is highly dependant on the charge transfer and surface adsorption at the interface. Electrode Architecture: A three-dimensional manganese oxide supercapacitor electrode architecture is synthesized by leveraging percolation theory to develop a hierarchically designed tri-continuous percolated network. The three percolated phases include a faradaically-active material, electrically conductive material and pore-former templated void space. The micropores create pathways for ionic conductivity, while the nanoscale electrically conducting phase provides both bulk conductivity and local electron transfer with the electrochemically active phase. Zn Electrodeposition: Zn redox in air and water stable N-ethyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide, [C2nmm][NTf2] is presented. Under various conditions, characterization of overpotential, kinetics and diffusion of Zn species and morphological evolution as a function of overpotential and Zn concentration are analyzed. The surface stress evolution during Zn deposition is examined where grain size and texturing play significant rolls in compressive stress generation. Morphological repeatability in the ILs led to a novel study of purity in ionic liquids where it is found that surface adsorption of residual amine and chloride from the organic synthesis affect growth characteristics. The drivers of this work are to understand the processes occurring at the electrode-electrolyte interface and with that knowledge, engineer systems yielding optimal performance. With this in mind, the design of a bulk supercapacitor electrode architecture with excellent composite specific capacitances, as well as develop conditions producing ideal Zn deposition morphologies was completed.
ContributorsEngstrom, Erika (Author) / Friesen, Cody (Thesis advisor) / Buttry, Daniel (Committee member) / Sieradzki, Karl (Committee member) / Arizona State University (Publisher)
Created2011
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Description
There is an inexorable link between structure and stress, both of which require study in order to truly understand the physics of thin films. To further our knowledge of thin films, the relationship between structure and stress development was examined in three separate systems in vacuum. The first was continued

There is an inexorable link between structure and stress, both of which require study in order to truly understand the physics of thin films. To further our knowledge of thin films, the relationship between structure and stress development was examined in three separate systems in vacuum. The first was continued copper thin film growth in ultra-high vacuum after adsorption of a sub-monolayer quantity of oxygen. Results showed an increase in compressive stress generation, and theory was proposed to explain the additional compressive stress within the films. The second system explored was the adsorption of carbon monoxide on the platinum {111} surface in vacuum. The experiments displayed a correlation between known structural developments in the adsorbed carbon monoxide adlayer and the surface stress state of the system. The third system consisted of the growth and annealing stresses of ice thin films at cryogenic temperatures in vacuum. It was shown that the growth stresses are clearly linked to known morphology development from literature, with crystalline ice developing compressive and amorphous ice developing tensile stresses respectively, and that amorphous ice films develop additional tensile stresses upon annealing.
ContributorsKennedy, Jordan (Author) / Friesen, Cody (Thesis advisor) / Sieradzki, Karl (Committee member) / Crozier, Peter (Committee member) / Arizona State University (Publisher)
Created2011
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Over the last decade copper electrodeposition has become the dominant process by which microelectronic interconnects are made. Replacing ultra-high vacuum evaporative film growth, the technology known as the Cu damascene process has been widely implemented in the microelectronics industry since the early 2000s. The transition from vacuum film growth to

Over the last decade copper electrodeposition has become the dominant process by which microelectronic interconnects are made. Replacing ultra-high vacuum evaporative film growth, the technology known as the Cu damascene process has been widely implemented in the microelectronics industry since the early 2000s. The transition from vacuum film growth to electrodeposition was enabled by solution chemistries that provide "bottom-up" or superfilling capability of vias and trenches. While the process has been and is used widely, the actual mechanisms responsible for superfilling remain relatively unknown. This dissertation presents and discusses the background and results of experimental investigations that have been done using in situ electrochemical surface stress monitoring techniques to study the evolution of stress on Cu{111} thin film electrodes. Because of its extreme sensitivity to the structure on both the electrode and solution sides of the interface, surface stress monitoring as analytical technique is well suited for the study of electrodeposition. These ultra-high resolution stress measurements reveal the dynamic response of copper electrodes to a number of electrochemical and chemical experimental variables. In the case of constant current pulsed deposition and stripping, the surface stress evolution depends not only on the magnitude of the current pulse, but also shows a marked response to plating bath composition. The plating bath chemistries used in this work include (1) additive free, (2) deposition suppressing solutions that include polyethylene glycol (PEG) and sodium chloride (NaCl) as well as (3) full additive solution combinations which contain PEG, NaCl, and a one of two deposition accelerating species (bis-(sodiumsulfopropyl)disulfide (SPS) or mercaptopropane sulfonic acid (MPS)). The development of thin film stress is further investigated through a series of solution exchange experiments that correlate the magnitude of electrode exchange current density and the stress state of the film. Remarkably, stress changes as large as ~8.5 N/m are observed during solution exchanges at the open circuit potential. Overall, this research demonstrates that solution chemistry can have a large impact on thin film stress evolution, even for very small deposition thicknesses (e.g. <10 ML) or in the absence of net addition or removal of material from the electrode.
ContributorsHeaton, Thomas Stanley (Author) / Friesen, Cody (Thesis advisor) / Buttry, Daniel (Committee member) / Sieradzki, Karl (Committee member) / Arizona State University (Publisher)
Created2011
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Coverage of Black soccer players by Italian media outlets perpetuate narratives rooted in anti-Black racism. These narratives reflect the country’s changing attitude toward immigration. Historically a country from which citizens emigrated, it is now a recipient of immigrants from Africa. These changing demographics have also caused a shift in the

Coverage of Black soccer players by Italian media outlets perpetuate narratives rooted in anti-Black racism. These narratives reflect the country’s changing attitude toward immigration. Historically a country from which citizens emigrated, it is now a recipient of immigrants from Africa. These changing demographics have also caused a shift in the focus of racism in Italy, from discrimination against southern Italians to anti-Black racism. As the country has explored what defines a unified Italian identity, Afro-Italians have been excluded. This study evaluates how these perceptions of Afro-Italian soccer players manifest according to various racial frames, and the frequency with which they do so in three Italian sports dailies: La Gazzetta dello Sport, Corriere dello Sport – Stadio, and Tuttosport. In this context, Afro-Italian refers to an Italian citizen of African descent, and anti-Black racism denotes any form of discrimination, stereotyping, or racism that specifically impacts those of African descent. For this study, a representative sample was collected consisting of website coverage published by the three sports dailies: articles devoted to Mario Balotelli that appeared between 2007 and 2014, and articles devoted to Moise Kean between 2016 and 2019. Three coders recorded the content of the sample articles on a spreadsheet organized by the type of racial frame applied to Black athletes. The analysis reveals that the players were frequently portrayed as being incapable of self-determination and of having an innate, natural athletic capability, rather than one honed through practice. The coders noted that in addition to explicit racial framing, there were also instances of implicit and subtle ways these racial frames manifest. In future research, the coding procedure will need to be adapted to account for these more layered and nuanced manifestations of anti-Black racism.

Created2021-05
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When examining the average college campus, it becomes obvious that students feel rushed from one place to another as they try to participate in class, clubs, and extracurricular activities. One way that students can feel more comfortable and relaxed around campus is to introduce the aspect of gaming. Studies show

When examining the average college campus, it becomes obvious that students feel rushed from one place to another as they try to participate in class, clubs, and extracurricular activities. One way that students can feel more comfortable and relaxed around campus is to introduce the aspect of gaming. Studies show that “Moderate videogame play has been found to contribute to emotional stability” (Jones, 2014). This demonstrates that the stress of college can be mitigated by introducing the ability to interact with video games. This same concept has been applied in the workplace, where studies have shown that “Gaming principles such as challenges, competition, rewards and personalization keep employees engaged and learning” (Clark, 2020). This means that if we manage to gamify the college experience, students will be more engaged which will increase and stabilize the retention rate of colleges which utilize this type of experience. Gaming allows students to connect with their peers in a casual environment while also allowing them to find resources around campus and find new places to eat and relax. We plan to gamify the college experience by introducing augmented reality in the form of an app. Augmented reality is “. . . a technology that combines virtual information with the real world” (Chen, 2019). College students will be able to utilize the resources and amenities available to them on campus while completing quests that help them within the application. This demonstrates the ability for video games to engage students using artificial tasks but real actions and experiences which help them feel more connected to campus. Our Founders Lab team has developed and tested an AR application that can be used to connect students with their campus and the resources available to them.

ContributorsKlein, Jonathan (Co-author) / Rangarajan, Padmapriya (Co-author) / Li, Shimei (Co-author) / Byrne, Jared (Thesis director) / Pierce, John (Committee member) / School of International Letters and Cultures (Contributor) / Department of Management and Entrepreneurship (Contributor) / Sandra Day O'Connor College of Law (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Before the COVID-19 pandemic, there was a great need for United States’ restaurants to “go green” due to consumers’ habits of frequently eating out. Unfortunately, COVID-19 has caused this initiative to lose traction. While the amount of customers ordering takeout has increased, there is less emphasis on sustainability.<br/>Plastic is known

Before the COVID-19 pandemic, there was a great need for United States’ restaurants to “go green” due to consumers’ habits of frequently eating out. Unfortunately, COVID-19 has caused this initiative to lose traction. While the amount of customers ordering takeout has increased, there is less emphasis on sustainability.<br/>Plastic is known for its harmful effects on the environment and the extreme length of time it takes to decompose. According to the International Union for Conservation of Nature (IUCN), almost 8 million tons of plastic end up in the oceans at an annual rate, threatening not only the safety of marine species but also human health. Modern food packaging materials have included a blend of synthetic ingredients, trickling into our daily lives and polluting the air, water, and land. Single-use plastic items slowly degrade into microplastics and can take up to hundreds of years to biodegrade.<br/>Due to COVID-19, restaurants have switched to takeout and delivery options to adapt to the new business environment and guidelines enforced by the Center of Disease Control (CDC) mandated guidelines. Some of these guidelines include: notices encouraging social distancing and mask-wearing, mandated masks for employees, and easy access to sanitary supplies. This cultural shift is motivating restaurants to search for a quick, cheap, and easy fix to adapt to the increased demand of take-out and delivery methods. This increases their plastic consumption of items such as plastic bags/paper bags, styrofoam containers, and beverage cups. Plastic is the most popular takeout material because of its price and durability as well as allowing for limited contamination and easy disposability.<br/>Almost all food products come in packaging and this, more often than not, is single-use. Food is the largest market out of all the packaging industry, maintaining roughly two-thirds of material going to food. The US Environmental Protection Agency reports that almost half of all municipal solid waste is made up of food and food packaging materials. In 2014, over 162 million tons of packaging material waste was generated in the states. This typically contains toxic inks and dyes that leach into groundwater and soil. When degrading, pieces of plastic absorb toxins like PCBs and pesticides, and then each piece will, in turn, release toxic chemicals like Bisphenol-A. Even before being thrown away, it causes negative effects for the environment. The creation of packaging materials uses many resources such as petroleum and chemicals and then releases toxic byproducts. Such byproducts include sludge containing contaminants, greenhouse gases, and heavy metal and particulate matter emissions. Unlike many other industries, plastic manufacturing has actually increased production. Demand has increased and especially in the food industry to keep things sanitary. This increase in production is reflective of the increase in waste. <br/>Although restaurants have implemented their own sustainable initiatives to combat their carbon footprint, the pandemic has unfortunately forced restaurants to digress. For example, Just Salad, a fast-food restaurant chain, incentivized customers with discounted meals to use reusable bowls which saved over 75,000 pounds of plastic per year. However, when the pandemic hit, the company halted the program to pivot towards takeout and delivery. This effect is apparent on an international scale. Singapore was in lock-down for eight weeks and during that time, 1,470 tons of takeout and food delivery plastic waste was thrown out. In addition, the Hong Kong environmental group Greeners Action surveyed 2,000 people in April and the results showed that people are ordering out twice as much as last year, doubling the use of plastic.<br/>However, is this surge of plastic usage necessary in the food industry or are there methods that can be used to reduce the amount of waste production? The COVID-19 pandemic caused a fracture in the food system’s supply chain, involving food, factory, and farm. This thesis will strive to tackle such topics by analyzing the supply chains of the food industry and identify areas for sustainable opportunities. These recommendations will help to identify areas for green improvement.

ContributorsDeng, Aretha (Co-author) / Tao, Adlar (Co-author) / Vargas, Cassandra (Co-author) / Printezis, Antonios (Thesis director) / Konopka, John (Committee member) / Department of Supply Chain Management (Contributor) / School of International Letters and Cultures (Contributor) / Department of Information Systems (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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What is being done to promote cultural sensitivity in healthcare settings? To find answers and solutions to the widespread deficit of cultural competence in the health care industry, this case study interviews a varied sample of five physicians consisting of three men and two women in clinical, academic, and administrative

What is being done to promote cultural sensitivity in healthcare settings? To find answers and solutions to the widespread deficit of cultural competence in the health care industry, this case study interviews a varied sample of five physicians consisting of three men and two women in clinical, academic, and administrative positions. The hypothesis was physicians do not receive cultural sensitivity training in medical school and as a result, they have to find other ways to learn about the cultures of their patients. None of the participants had received formal cultural competency training in medical school and all of them found methods to improve their cultural literacy. The study uncovered the cultural training physicians do receive is sporadic and inconsistent, which can cause some disconnect between education and real-life clinical practice. Many solutions to improve cultural competency in health care delivery are presented. The results of this exploratory research should be used to inspire future conversations about cultural competency in health care as well as the creation of support and educational services and materials to medical students and health care workers on improving cultural sensitivity in clinical practice.

ContributorsWilson, Diane Kathleen (Author) / Cortese, Denis (Thesis director) / Estevez, Dulce (Committee member) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Much of Nepal lacks access to clean drinking water, and many water sources are contaminated with arsenic at concentrations above both World Health Organization and local Nepalese guidelines. While many water treatment technologies exist, it is necessary to identify those that are easily implementable in developing areas. One simple treatment

Much of Nepal lacks access to clean drinking water, and many water sources are contaminated with arsenic at concentrations above both World Health Organization and local Nepalese guidelines. While many water treatment technologies exist, it is necessary to identify those that are easily implementable in developing areas. One simple treatment that has gained popularity is biochar—a porous, carbon-based substance produced through pyrolysis of biomass in an oxygen-free environment. Arizona State University’s Engineering Projects in Community Service (EPICS) has partnered with communities in Nepal in an attempt to increase biochar production in the area, as it has several valuable applications including water treatment. Biochar’s arsenic adsorption capability will be investigated in this project with the goal of using the biochar that Nepalese communities produce to remove water contaminants. It has been found in scientific literature that biochar is effective in removing heavy metal contaminants from water with the addition of iron through surface activation. Thus, the specific goal of this research was to compare the arsenic adsorption disparity between raw biochar and iron-impregnated biochar. It was hypothesized that after numerous bed volumes pass through a water treatment column, iron from the source water will accumulate on the surface of raw biochar, mimicking the intentionally iron-impregnated biochar and further increasing contaminant uptake. It is thus an additional goal of this project to compare biochar loaded with iron through an iron-spiked water column and biochar impregnated with iron through surface oxidation. For this investigation, the biochar was crushed and sieved to a size between 90 and 100 micrometers. Two samples were prepared: raw biochar and oxidized biochar. The oxidized biochar was impregnated with iron through surface oxidation with potassium permanganate and iron loading. Then, X-ray fluorescence was used to compare the composition of the oxidized biochar with its raw counterpart, indicating approximately 0.5% iron in the raw and 1% iron in the oxidized biochar. The biochar samples were then added to batches of arsenic-spiked water at iron to arsenic concentration ratios of 20 mg/L:1 mg/L and 50 mg/L:1 mg/L to determine adsorption efficiency. Inductively coupled plasma mass spectrometry (ICP-MS) analysis indicated an 86% removal of arsenic using a 50:1 ratio of iron to arsenic (1.25 g biochar required in 40 mL solution), and 75% removal with a 20:1 ratio (0.5 g biochar required in 40 mL solution). Additional samples were then inserted into a column process apparatus for further adsorption analysis. Again, ICP-MS analysis was performed and the results showed that while both raw and treated biochars were capable of adsorbing arsenic, they were exhausted after less than 70 bed volumes (234 mL), with raw biochar lasting 60 bed volumes (201 mL) and oxidized about 70 bed volumes (234 mL). Further research should be conducted to investigate more affordable and less laboratory-intensive processes to prepare biochar for water treatment.

ContributorsLaird, Ashlyn (Author) / Schoepf, Jared (Thesis director) / Westerhoff, Paul (Committee member) / Chemical Engineering Program (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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The purpose of this research is to exploit the neglect of specific populations and diseases in Latin America through an epidemiological literature review. As a small part of a larger publication, the foci of this research was the infectious disease, helminthiasis. Using manually indexed abstracts from the National Library of

The purpose of this research is to exploit the neglect of specific populations and diseases in Latin America through an epidemiological literature review. As a small part of a larger publication, the foci of this research was the infectious disease, helminthiasis. Using manually indexed abstracts from the National Library of Medicine database in PubMed, 4,594 papers were synthesized and then processed for further review. Of those papers, 29 provided information about helminths in indigenous populations. These papers were reviewed and used in prevalence data extraction and variable analysis. The main conclusion was to reveal the fact that from an entire health database less than 30 papers provided information about the persistence of helminths in indigenous communities of Latin America. Not only that but the few papers that could be analyzed had consistently high prevalence ratios.

ContributorsGregory, Cassandre June (Author) / Hurtado, Ana Magdalena (Thesis director) / Estevez, Dulce (Committee member) / School of Life Sciences (Contributor) / School of Human Evolution & Social Change (Contributor, Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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The microbiome and the immune system are known to work in conjunction to modulate the clearance of pathogens and tolerance of beneficial microbes. A growing area of research seeks to study the potential extent of the involvement of the microbiome in modulating and supporting the immune system during acute allograft

The microbiome and the immune system are known to work in conjunction to modulate the clearance of pathogens and tolerance of beneficial microbes. A growing area of research seeks to study the potential extent of the involvement of the microbiome in modulating and supporting the immune system during acute allograft rejection. It has been hypothesized that the localized microbiota in each organ produce metabolites that instigate inflammatory immune responses, but whether microbiota interactions precipitate acute allograft rejection is unknown. Therefore, this study focuses on microbiome shifts in the gut and kidney after inducing acute renal transplant rejection in order to implicate gut dysbiosis as a precursor or supporter of allograft rejection. This study also subsequently explores the use of an immune-modulating protein in order to determine differences in the outcome of transplant rejection and potential differences in intestinal microbial load. This experiment sought to induce rejection in BALB/c mice through the use of C57BL/6 mouse renal slivers. Microbiome abundance was analyzed in all experimental groups. Understanding the role of the microbiome in transplant rejection has vast clinical implications and has the potential to enhance pre- and post-operative treatment, and immune management and quality of life following organ transplant.

ContributorsKokott, Kristiana Tara (Author) / Lim, Efrem (Thesis director) / Lucas, Alexandra (Committee member) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2021-05