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Description
The field of bioprocess engineering has become an increasingly popular route to produce chemicals and fuels in a sustainable fashion. Bioprocessing is an interdisciplinary field that joins chemical engineering, metabolic engineering, and synthetic biology to tackle problems that will arise from the ongoing use of products derived from non-renewable resources. This study will overlook two effective tools that are widely used in the bioprocessing field. The first tool that was studied was strain optimization for biochemical production. This involves genetic manipulation of microbial hosts to create strains that are more efficient at producing the desired products. The second tool that was studied was adaptive laboratory evolution which is used to enhance overall cellular fitness. Enhancing the overall fitness and efficiency of these microbial production factories, allows for innovation and growth in the biochemical industry. Creating sustainable and renewable solutions for both specialty and commodity chemicals.
Strain optimization was specifically studied by enhancing inorganic carbon uptake in synechococcus sp. 7002. It is desired to have both high flux and high affinity transport for the rapid and efficient uptake of HCO3- for enhanced cell growth. The results found that the regulatory gene for carbon transporters in synechococcus genome was successfully deleted. Increasing the toxicity limits of 2-Phenylethanol was done by using adaptive laboratory evolution (ALE). ALE is a widely used practice in biotechnology studies to gain insights on mechanisms of molecular evolution and to better define the functionality of microbial cell factories. It was found that after growing E. coli BW25113 under selective conditions the genome evolved for a higher fitness medium with an increased concentration of 2-Phenylethanol. Overall, two key tools used in bioprocess engineering were successful studied to gain a better insight on the future of biochemical production industry.
Strain optimization was specifically studied by enhancing inorganic carbon uptake in synechococcus sp. 7002. It is desired to have both high flux and high affinity transport for the rapid and efficient uptake of HCO3- for enhanced cell growth. The results found that the regulatory gene for carbon transporters in synechococcus genome was successfully deleted. Increasing the toxicity limits of 2-Phenylethanol was done by using adaptive laboratory evolution (ALE). ALE is a widely used practice in biotechnology studies to gain insights on mechanisms of molecular evolution and to better define the functionality of microbial cell factories. It was found that after growing E. coli BW25113 under selective conditions the genome evolved for a higher fitness medium with an increased concentration of 2-Phenylethanol. Overall, two key tools used in bioprocess engineering were successful studied to gain a better insight on the future of biochemical production industry.
ContributorsSteeber, Gavin Lyle (Author) / Nielsen, David (Thesis director) / Jones, Christopher (Committee member) / Chemical Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The microalgae Scenedesmus have been regarded as a potential source for biofuel production, having up to ~30% of dry weight as lipids used for biodiesel fuel production. Electro-selective fermentation (ESF) is a novel approach that can selectively degrade proteins and carbohydrates while conserving lipids within algal cells, while simultaneously enhancing lipid wet-extraction and biohydrogenation. ESF is a combination of SF and Microbial Electrolysis Cell (MEC) technologies. Experiments reported here prove that ESF is an effective means of enhancing lipid wet-extraction by ~50% and achieving 36% higher lipid saturation conversion, compared to SF, over 30 days of semi-continuous operation. Anode-respiring bacteria (ARB) residing on the anode surface produced a current that led to increased rate of organic substrate utilization, protein degradation, and ultimately enhanced lipid extraction and biohydrogenation that converted unsaturated to saturated fatty-acids. Thus, ESF provides a promising method for enhancing lipid extraction for biofuel production.
ContributorsRastogi, Neil K (Author) / Rittmann, Bruce (Thesis director) / Liu, Liu (Committee member) / Chemical Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Following the 2008 financial crisis, two social movements emerged in the United States, both attempting to address economic anxieties and grievances, though from very different ideological positions. The Tea Party Movement and the Occupy Movement arose within a few years of one another, and both sought to explain the failure of the existing economic system, whether in terms of overregulation and government overreach, or in terms of political corruption and the failures of capitalism. Despite both movements seeking to address economic failures and anxieties, and both movements emerging within two years of one another, the Tea Party Movement and Occupy Movement had very different trajectories and outcomes. Putting aside the question of how to measure the success of a social movement, it is clear that the lasting effects of these two movements were quite different despite substantial similarities in the timing of these movements, and the economic anxieties which helped fuel them. While there are likely a constellation of factors which contributed to the differing outcomes between these two movements, the factors of interest in this analysis are the narratives espoused by these movements, and the relationship between narrative, and the organization and political activities of these movements.
ContributorsHallikainen, Hannah (Author) / Kubiak, Jeffrey (Thesis director) / Hechter, Michael (Committee member) / Chemical Engineering Program (Contributor) / School of Politics and Global Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The tendon-bone junction, also known as the enthesis, is crucial for properly transferring mechanical loadings during physical activity. During injury, current restoration procedures are insufficient for properly restoring tissue function. Thus, it is paramount to design alternative tissue engineered scaffolds to act as a template to the injured region and a regenerative response for tendon-bone repair. Thus, we utilized an offset electrospinning technique to fabricate a scaffold that mimics the native biochemical gradients present within the tendon-bone junction. To improve chemical gradient resolution, we implemented both insulating and conductive shields during offset electrospinning. Polycaprolactone fibers with either rhodamine or fluorescein were used to measure the scaffold fluorescent strength with distance. Without shields, at an offset of 4 cm, the chemical gradient resolution for rhodamine and fluorescein were 2.5 cm and 6.0 cm, respectively. During implementation of insulating shields, the gradient resolution for rhodamine and fluorescein improved to 2 cm and 0.5 cm, respectively. Lastly, grounded conductive shields improved gradient resolution for rhodamine and fluorescein to 1.0 cm and 1.5 cm, respectively.
ContributorsMiles, Corey (Author) / Holloway, Julianne (Thesis director) / Tindell, Raymond (Committee member) / Chemical Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The yeast project studies the growth of yeast Saccharomyces Cerevisiae (S. Cerevisiae) in high and low sulfate environments and analyzes the potential for genetically mutated plasmids to facilitate sulfate uptake in gene deficient yeast medias. The goal of the project was to transform the Sul1 and Sul2 transporters into the nutrient deficient yeast strain BY4743 and observe growth in conditions that would otherwise prohibit growth in order to create a model that can be used to study the effect of sulfate concentration on the transporters. The experimental results showed that expressing the sulfate transporters in the BY4743 strain provided the potential for the yeast to grow in nutrient-poor media. The growth potential model allows for further analysis on the sulfate transporters and will be used for research projects going forward.
ContributorsDickieson, Maxim Park (Author) / Nannenga, Brent (Thesis director) / Pena, Fred (Committee member) / Dean, Ira A. Fulton Schools of Engineering (Contributor) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
When it comes to the topic of chemical engineering, the general public has a set of neutral, if slightly uninformed perceptions that are largely tempered by the initial emotional responses to the field and its associated topics. These topics include the differentiation between chemical engineers and chemists, the importance and potential danger of the products they produce, as well as the association of the subject matter with less than favorable secondary education experiences. This thesis consists of first assessing the opinions of a population meant to represent the general public regarding these subjects, then exploring the potential improvements of opinion and understanding that may be yielded from presenting the subject matter by way of a concise learning tool, such as a video. The results of this effort showed that factual understanding can be at least incrementally improved for 18% of participants through this method, while the effect on opinions can range from being improved to maintaining an enduring indifference, with an average of 17% of participants seeing improvement. Further iteration of this methodology with more consistent, impartial survey methods and refined questions could potentially yield more noteworthy improvements within the subjective domain, with the resultant learning tool of that iteration being applicable as not only an instrument of educating the general public, but also as a means to recruit potential students to the ASU chemical engineering degree program.
ContributorsJanovsky, Trey Patrick (Author) / Taylor, David (Thesis director) / Martin, Thomas (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Lithium-ion batteries that employ an electrolyte consisting of LiFSI and TMP are shown to have better cycle performance than conventional carbonate electrolyte batteries at elevated temperatures. Additionally, an inorganic alumina or silica separator also improves cycling performance at high temperatures. Half-cells of Li metal and Li2TiO3 were constructed with LiFSI/TMP electrolyte and inorganic separators and cycled at increasing temperatures. Their cycle performance was compared to batteries with the same anode and cathode material that were prepared with conventional components. Half-cells using either the novel electrolyte or inorganic separators were able to continue cycling at temperatures up to 80 ℃, long after the conventionally prepared batteries had failed. A cell with a combination of the LiFSI/TMP electrolyte and silica separator still showed 75% capacity retention after 10 cycles at 85 ℃ as well.
ContributorsHait, Liam Bennett (Author) / Lin, Jerry (Thesis director) / Rafiz, Kishen (Committee member) / Chemical Engineering Program (Contributor) / Computing and Informatics Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Titanium dioxide (TiO2) is a photocatalytic material which has made its way into the European market for use within building materials (e.g. in photocatalytic cement). The air-cleaning and self-cleaning properties of TiO2 make it an attractive material for development. TiO2 has been widely studied to determine the mechanism by which it catalyzes reactions, but research into its use in photocatalytic cement has focused only on the percent pollutant removed and not the composition of the resulting gas. The current research focuses on examining the oxidation of methanol over the solid materials and the development of a methodology to study the formation of intermediates in the removal of the pollutant molecule. The initial methanol oxidation studies over the photocatalytic cement resulted in a reduction in the concentration of methanol and an increase in potential products. However, these studies identified several system challenges that led to a focus on the system design. It is recommended that future reactor systems optimize the transfer of material through the use of agitation and minimize the path length between the reactor cell and the FTIR gas cell. Furthermore, creating an air-tight system is paramount to the success of future studies.
ContributorsBenov, Emil Plamenov (Author) / Andino, Jean (Thesis director) / Schoepf, Jared (Committee member) / Chemical Engineering Program (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
This project evaluates the success that a Food Waste assignment had on reducing food waste by exploring factors that suggest waste minimization. Previous ASB 370/394: Ethics of Eating students were surveyed regarding their thoughts on their current food waste behavior and what food waste strategies they implemented to reduce their waste. The success of the assignment was determined using SPSS statistical software. Respondents reported that foods that they waste the most were vegetables, fruits, and bread and most respondents indicated that they threw away 1-2 cups of food per week, typically only when they clean out their fridge and/or pantry. Participants revealed the main reasons for their food waste were “I buy too much,” followed by “do not have time to prepare the food I buy,” and “my produce didn’t look appealing anymore.” Based on the results from the survey, over 60% of respondents indicated that they had changed their food waste behavior to produce less waste. The Food Waste Assignment was deemed a success in encouraging students to limit their food waste due to the majority of students indicating they change their behavior after completing the assignment. The three main tactics students implemented to reduce their food waste were: “eating more leftovers,” “proper food storage,” and, “meal planning.” While the Food Waste Assignment was successful, ways to improve the assignment were still identified. To help students address their food waste behavior, reading or videos on ways to prevent food waste or suggestions for students to improve their food waste could be provided.
ContributorsMicksch, Jessica Lee (Co-author, Co-author) / Stotts, Rhian (Thesis director) / Bidner, Laura (Committee member) / Industrial, Systems & Operations Engineering Prgm (Contributor) / Environmental and Resource Management (Contributor) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The development of Corynebacterium glutamicum for the microbial production of high-value products has made this bacterium an industrial workhorse. This metabolically engineered microbe is capable of accumulating and secreting flavonoids, a class of high functioning compounds found in plants. In human health, flavonoids are known to have powerful antioxidant, anti-inflammatory, anticancer, and antiviral properties which has led the growing interest to produce these compounds commercially. Recent literature seeks to overcome potential pathway bottlenecks to optimize flavonoid production by regulating protein expression within the central carbon, shikimate, chorismate, and fatty acid synthesis pathways. This paper reviews engineering strategies performed to increase the precursor titers of malonyl-CoA, phenylalanine, and tyrosine for increased flavonoid production.
ContributorsBalbas, Elissa (Author) / Varman, Arul (Thesis director) / Nielsen, David (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05