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- Creators: Barrett, The Honors College
- Status: Published
Description
Geology and its tangential studies, collectively known and referred to in this thesis as geosciences, have been paramount to the transformation and advancement of society, fundamentally changing the way we view, interact and live with the surrounding natural and built environment. It is important to recognize the value and importance of this interdisciplinary scientific field while reconciling its ties to imperial and colonizing extractive systems which have led to harmful and invasive endeavors. This intersection among geosciences, (environmental) justice studies, and decolonization is intended to promote inclusive pedagogical models through just and equitable methodologies and frameworks as to prevent further injustices and promote recognition and healing of old wounds. By utilizing decolonial frameworks and highlighting the voices of peoples from colonized and exploited landscapes, this annotated syllabus tackles the issues previously described while proposing solutions involving place-based education and the recentering of land within geoscience pedagogical models. (abstract)
ContributorsReed, Cameron E (Author) / Richter, Jennifer (Thesis director) / Semken, Steven (Committee member) / School of Earth and Space Exploration (Contributor, Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
The ASU COVID-19 testing lab process was developed to operate as the primary testing site for all ASU staff, students, and specified external individuals. Tests are collected at various collection sites, including a walk-in site at the SDFC and various drive-up sites on campus; analysis is conducted on ASU campus and results are distributed virtually to all patients via the Health Services patient portal. The following is a literature review on past implementations of various process improvement techniques and how they can be applied to the ABCTL testing process to achieve laboratory goals. (abstract)
ContributorsKrell, Abby Elizabeth (Co-author) / Bruner, Ashley (Co-author) / Ramesh, Frankincense (Co-author) / Lewis, Gabriel (Co-author) / Barwey, Ishna (Co-author) / Myers, Jack (Co-author) / Hymer, William (Co-author) / Reagan, Sage (Co-author) / Compton, Carolyn (Thesis director) / McCarville, Daniel R. (Committee member) / Industrial, Systems & Operations Engineering Prgm (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Membrane technology is a viable option to debottleneck distillation processes and minimize the energy burden associated with light hydrocarbon mixture separations. Zeolitic imidazolate frameworks (ZIFs) are a new class of microporous metal-organic frameworks with highly tailorable zeolitic pores and unprecedented separation characteristics. ZIF-8 membranes demonstrate superior separation performance for propylene/propane (C3) and hydrogen/hydrocarbon mixtures at room temperature. However, to date, little is known about the static thermal stability and ethylene/ethane (C2) separation characteristics of ZIF-8. This dissertation presents a set of fundamental studies to investigate the thermal stability, transport and modification of ZIF-8 membranes for light hydrocarbon separations.
Static TGA decomposition kinetics studies show that ZIF-8 nanocrystals maintain their crystallinity up to 200○C in inert, oxidizing and reducing atmospheres. At temperatures of 250○C and higher, the findings herein support the postulation that ZIF-8 nanocrystals undergo temperature induced decomposition via thermolytic bond cleaving reactions to form an imidazole-Zn-azirine structure. The crystallinity/bond integrity of ZIF-8 membrane thin films is maintained at temperatures below 150○C.
Ethane and ethylene transport was studied in single and binary gas mixtures. Thermodynamic parameters derived from membrane permeation and crystal adsorption experiments show that the C2 transport mechanism is controlled by adsorption rather than diffusion. Low activation energy of diffusion values for both C2 molecules and limited energetic/entropic diffusive selectivity are observed for C2 molecules despite being larger than the nominal ZIF-8 pore aperture and is due to pore flexibility.
Finally, ZIF-8 membranes were modified with 5,6 dimethylbenzimidazole through solvent assisted membrane surface ligand exchange to narrow the pore aperture for enhanced molecular sieving. Results show that relatively fast exchange kinetics occur at the mainly at the outer ZIF-8 membrane surface between 0-30 minutes of exchange. Short-time exchange enables C3 selectivity increases with minimal olefin permeance losses. As the reaction proceeds, the ligand exchange rate slows as the 5,6 DMBIm linker proceeds into the ZIF-8 inner surface, exchanges with the original linker and first disrupts the original framework’s crystallinity, then increases order as the reaction proceeds. The ligand exchange rate increases with temperature and the H2/C2 separation factor increases with increases in ligand exchange time and temperature.
Static TGA decomposition kinetics studies show that ZIF-8 nanocrystals maintain their crystallinity up to 200○C in inert, oxidizing and reducing atmospheres. At temperatures of 250○C and higher, the findings herein support the postulation that ZIF-8 nanocrystals undergo temperature induced decomposition via thermolytic bond cleaving reactions to form an imidazole-Zn-azirine structure. The crystallinity/bond integrity of ZIF-8 membrane thin films is maintained at temperatures below 150○C.
Ethane and ethylene transport was studied in single and binary gas mixtures. Thermodynamic parameters derived from membrane permeation and crystal adsorption experiments show that the C2 transport mechanism is controlled by adsorption rather than diffusion. Low activation energy of diffusion values for both C2 molecules and limited energetic/entropic diffusive selectivity are observed for C2 molecules despite being larger than the nominal ZIF-8 pore aperture and is due to pore flexibility.
Finally, ZIF-8 membranes were modified with 5,6 dimethylbenzimidazole through solvent assisted membrane surface ligand exchange to narrow the pore aperture for enhanced molecular sieving. Results show that relatively fast exchange kinetics occur at the mainly at the outer ZIF-8 membrane surface between 0-30 minutes of exchange. Short-time exchange enables C3 selectivity increases with minimal olefin permeance losses. As the reaction proceeds, the ligand exchange rate slows as the 5,6 DMBIm linker proceeds into the ZIF-8 inner surface, exchanges with the original linker and first disrupts the original framework’s crystallinity, then increases order as the reaction proceeds. The ligand exchange rate increases with temperature and the H2/C2 separation factor increases with increases in ligand exchange time and temperature.
ContributorsJames, Joshua B. (Author) / Lin, Jerry Y.S. (Thesis advisor) / Emady, Heather (Committee member) / Lind, Mary Laura (Committee member) / Mu, Bin (Committee member) / Seo, Dong (Committee member) / Arizona State University (Publisher)
Created2017
Description
In material science, microstructure plays a key role in determining properties, which further determine utility of the material. However, effectively measuring microstructure evolution in real time remains an challenge. To date, a wide range of advanced experimental techniques have been developed and applied to characterize material microstructure and structural evolution on different length and time scales. Most of these methods can only resolve 2D structural features within a narrow range of length scale and for a single or a series of snapshots. The currently available 3D microstructure characterization techniques are usually destructive and require slicing and polishing the samples each time a picture is taken. Simulation methods, on the other hand, are cheap, sample-free and versatile without the special necessity of taking care of the physical limitations, such as extreme temperature or pressure, which are prominent
issues for experimental methods. Yet the majority of simulation methods are limited to specific circumstances, for example, first principle computation can only handle several thousands of atoms, molecular dynamics can only efficiently simulate a few seconds of evolution of a system with several millions particles, and finite element method can only be used in continuous medium, etc. Such limitations make these individual methods far from satisfaction to simulate macroscopic processes that a material sample undergoes up to experimental level accuracy. Therefore, it is highly desirable to develop a framework that integrate different simulation schemes from various scales
to model complicated microstructure evolution and corresponding properties. Guided by such an objective, we have made our efforts towards incorporating a collection of simulation methods, including finite element method (FEM), cellular automata (CA), kinetic Monte Carlo (kMC), stochastic reconstruction method, Discrete Element Method (DEM), etc, to generate an integrated computational material engineering platform (ICMEP), which could enable us to effectively model microstructure evolution and use the simulated microstructure to do subsequent performance analysis. In this thesis, we will introduce some cases of building coupled modeling schemes and present
the preliminary results in solid-state sintering. For example, we use coupled DEM and kinetic Monte Carlo method to simulate solid state sintering, and use coupled FEM and cellular automata method to model microstrucutre evolution during selective laser sintering of titanium alloy. Current results indicate that joining models from different length and time scales is fruitful in terms of understanding and describing microstructure evolution of a macroscopic physical process from various perspectives.
issues for experimental methods. Yet the majority of simulation methods are limited to specific circumstances, for example, first principle computation can only handle several thousands of atoms, molecular dynamics can only efficiently simulate a few seconds of evolution of a system with several millions particles, and finite element method can only be used in continuous medium, etc. Such limitations make these individual methods far from satisfaction to simulate macroscopic processes that a material sample undergoes up to experimental level accuracy. Therefore, it is highly desirable to develop a framework that integrate different simulation schemes from various scales
to model complicated microstructure evolution and corresponding properties. Guided by such an objective, we have made our efforts towards incorporating a collection of simulation methods, including finite element method (FEM), cellular automata (CA), kinetic Monte Carlo (kMC), stochastic reconstruction method, Discrete Element Method (DEM), etc, to generate an integrated computational material engineering platform (ICMEP), which could enable us to effectively model microstructure evolution and use the simulated microstructure to do subsequent performance analysis. In this thesis, we will introduce some cases of building coupled modeling schemes and present
the preliminary results in solid-state sintering. For example, we use coupled DEM and kinetic Monte Carlo method to simulate solid state sintering, and use coupled FEM and cellular automata method to model microstrucutre evolution during selective laser sintering of titanium alloy. Current results indicate that joining models from different length and time scales is fruitful in terms of understanding and describing microstructure evolution of a macroscopic physical process from various perspectives.
ContributorsChen, Shaohua (Author) / Jiao, Yang (Thesis advisor) / Wang, Qinghua (Committee member) / Emady, Heather (Committee member) / Gel, Aytekin (Committee member) / Arizona State University (Publisher)
Created2018
Description
Granulation is a process within particle technology where a liquid binding agent is added to a powder bed to create larger granules to modify bulk properties for easier processing. Three sets of experiments were conducted to screen for which factors had the greatest effect on granule formation, size distribution, and morphological properties when wet granulating microcrystalline cellulose and water. Previous experiments had identified the different growth regimes within wet granulation, as well as the granule formation mechanisms in single-drop granulation experiments, but little research has been conducted to determine how results extracted from single drop experiments could be used to better understand the first principles that drive high shear granulation. The experiment found that under a liquid solid ratio of 110%, the granule growth rate was linear as opposed to the induction growth regime experienced at higher liquid solid ratios. L/S ratios less than 100% led to a bimodal distribution comprised of large distributions of ungranulated powder and large irregular granules. Insufficient water hampered the growth of granules due to lack of enough water bridges to connect the granules and powder, while the large molecules continued to agglomerate with particles as they rotated around the mixer. The nozzle end was augmented so that drop size as well as drop height could be adjusted and compared to single-drop granulation experiments in proceeding investigations. As individual factors, neither augmentation had significant contributions to granule size, but preliminary screens identified that interaction between increasing L/S ratio and decreasing drop size could lead to narrower distributions of particles as well as greater circularity. Preliminary screening also identified that decreasing the drop height of the nozzle could increase the rate of particle growth during the 110% L/S trials without changing the growth mechanisms, indicating a way to alter the rate of steady-state particle growth. This paper screens for which factors are most pertinent to associating single-drop and wet granulation in order to develop granulation models that can ascertain information from single-drop granulations and predict the shape and size distribution of any wet granulation, without the need to run costly wet granulation experiments.
ContributorsLay, Michael (Author) / Emady, Heather (Thesis advisor) / Muhich, Christopher (Committee member) / Holloway, Julianne (Committee member) / Arizona State University (Publisher)
Created2019
Description
Rotary drums are commonly used for their high heat and mass transfer rates in the manufacture of cement, pharmaceuticals, food, and other particulate products. These processes are difficult to model because the particulate behavior is governed by the process conditions such as particle size, particle size distribution, shape, composition, and operating parameters, such as fill level and rotation rate. More research on heat transfer in rotary drums will increase operating efficiency, leading to significant energy savings on a global scale.
This research utilizes infrared imaging to investigate the effects of fill level and rotation rate on the particle bed hydrodynamics and the average wall-particle heat transfer coefficient. 3 mm silica beads and a stainless steel rotary drum with a diameter of 6 in and a length of 3 in were used at fill levels of 10 %, 17.5 %, and 25 %, and rotation rates of 2 rpm, 6 rpm, and 10 rpm. Two full factorial designs of experiments were completed to understand the effects of these factors in the presence of conduction only (Case 1) and conduction with forced convection (Case 2). Particle-particle friction caused the particle bed to stagnate at elevated temperatures in Case 1, while the inlet air velocity in Case 2 dominated the particle friction effects to maintain the flow profile. The maximum heat transfer coefficient was achieved at a high rotation rate and low fill level in Case 1, and at a high rotation rate and high fill level in Case 2. Heat losses from the system were dominated by natural convection between the hot air in the drum and the external surroundings.
This research utilizes infrared imaging to investigate the effects of fill level and rotation rate on the particle bed hydrodynamics and the average wall-particle heat transfer coefficient. 3 mm silica beads and a stainless steel rotary drum with a diameter of 6 in and a length of 3 in were used at fill levels of 10 %, 17.5 %, and 25 %, and rotation rates of 2 rpm, 6 rpm, and 10 rpm. Two full factorial designs of experiments were completed to understand the effects of these factors in the presence of conduction only (Case 1) and conduction with forced convection (Case 2). Particle-particle friction caused the particle bed to stagnate at elevated temperatures in Case 1, while the inlet air velocity in Case 2 dominated the particle friction effects to maintain the flow profile. The maximum heat transfer coefficient was achieved at a high rotation rate and low fill level in Case 1, and at a high rotation rate and high fill level in Case 2. Heat losses from the system were dominated by natural convection between the hot air in the drum and the external surroundings.
ContributorsBoepple, Brandon (Author) / Emady, Heather (Thesis advisor) / Muhich, Christopher (Committee member) / Holloway, Julianne (Committee member) / Arizona State University (Publisher)
Created2019
Description
The Basilisk lizard is known for its agile locomotion capabilities on granular and aquatic media making it an impressive model organism for studying multi-terrain locomotion mechanics. The work presented here is aimed at understanding locomotion characteristics of Basilisk lizards through a systematic series of robotic and animal experiments. In this work, a Basilisk lizard inspired legged robot with bipedal and quadrupedal locomotion capabilities is presented. A series of robot experiments are conducted on dry and wet (saturated) granular media to determine the effects of gait parameters and substrate saturation, on robot velocity and energetics. Gait parameters studied here are stride frequency and stride length. Results of robot experiments are compared with previously obtained animal data. It is observed that for a fixed robot stride frequency, velocity and stride length increase with increasing saturation, confirming the locomotion characteristics of the Basilisk lizard. It is further observed that with increasing saturation level, robot cost of transport decreases. An identical series of robot experiments are performed with quadrupedal gait to determine effects of gait parameters on robot performance. Generally, energetics of bipedal running is observed to be higher than quadrupedal operation. Experimental results also reveal how gait parameters can be varied to achieve different desired velocities depending on the substrate saturation level. In addition to robot experiments on granular media, a series of animal experiments are conducted to determine and characterize strategies
exhibited by Basilisk lizards when transitioning from granular to aquatic media.
exhibited by Basilisk lizards when transitioning from granular to aquatic media.
ContributorsJayanetti, Vidu (Author) / Marvi, Hamid (Thesis advisor) / Emady, Heather (Committee member) / Lee, Hyunglae (Committee member) / Arizona State University (Publisher)
Created2018
Description
For as long as humans have been working, they have been looking for ways to get that work done better, faster, and more efficient. Over the course of human history, mankind has created innumerable spectacular inventions, all with the goal of making the economy and daily life more efficient. Today, innovations and technological advancements are happening at a pace like never seen before, and technology like automation and artificial intelligence are poised to once again fundamentally alter the way people live and work in society. Whether society is prepared or not, robots are coming to replace human labor, and they are coming fast. In many areas artificial intelligence has disrupted entire industries of the economy. As people continue to make advancements in artificial intelligence, more industries will be disturbed, more jobs will be lost, and entirely new industries and professions will be created in their wake. The future of the economy and society will be determined by how humans adapt to the rapid innovations that are taking place every single day. In this paper I will examine the extent to which automation will take the place of human labor in the future, project the potential effect of automation to future unemployment, and what individuals and society will need to do to adapt to keep pace with rapidly advancing technology. I will also look at the history of automation in the economy. For centuries humans have been advancing technology to make their everyday work more productive and efficient, and for centuries this has forced humans to adapt to the modern technology through things like training and education. The thesis will additionally examine the ways in which the U.S. education system will have to adapt to meet the demands of the advancing economy, and how job retraining programs must be modernized to prepare workers for the changing economy.
ContributorsCunningham, Reed P. (Author) / DeSerpa, Allan (Thesis director) / Haglin, Brett (Committee member) / School of International Letters and Cultures (Contributor) / Department of Finance (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Businesses stand to face many uncertainties from the moment they start up to every moment in between. A business can try to recognize them and plan ahead, react to them as they occur, or be rocked by a black swan they never saw coming. How a business deals with unforeseen events can increase its potential for success or failure. With this in mind, there is no better bridge between the here and now and the future than planning for change in order to move a company toward preparing for change, adapting to change and achieving optimal results. Interested in taking a step toward the digital age, Alpha Homes Management, Inc. (Alpha Homes) sought our help to explore ideas and options to take their company to a new level. This Barrett Creative Project was centered on designing a system for Alpha Homes that will replace their outdated paper-based system with a more digital one. This aligns with the project also featured as a capstone project as required by the information technology degree expectations. In supplement to the capstone, and for the Barrett Creative Project, the final product was presented to the owners of Alpha Homes Management, Inc. to be utilized by the business. The end goal is to provide a platform which provides a paperless environment for documentation and bring the company a step closer to having a robust internet presence. Now that the web-based application product has been created and presented, the testing phase can now begin to evaluate its efficacy.
ContributorsBrice-Nash, Tristan (Co-author) / Alfawzan, Mohammad (Co-author) / Doheny, Damien (Thesis director) / Rodriguez, Carlos (Committee member) / Information Technology (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
An ethical dilemma is not a matter of “right” versus “wrong,” but rather it is a situation of conflicting values. A common ethical dilemma is that of honesty versus loyalty—is it better to tell the truth, or remain loyal to the company? In the Japanese culture, truth is circumstantial and can vary with different situations. In a way, the Japanese idea of honesty reflects how highly they value loyalty. This overlap of values results in the lack of an ethical dilemma for the Japanese, which creates a new risk for fraud. Without this struggle, a Japanese employee does not have strong justification against committing fraud if it aligns with his values of honesty and loyalty.
This paper looks at the Japanese values relating to honesty and loyalty to show how much these ideas overlap. The lack of a conflict of values creates a risk for fraud, which will be shown through an analysis of the scandals of two Japanese companies, Toshiba and Olympus. These scandals shine light on the complexity of the ethical dilemma for the Japanese employees; since their sense of circumstantial honesty encourages them to lie if it maintains the harmony of the group, there is little stopping them from committing the fraud that their superiors asked them to commit.
In a global economy, understanding the ways that values impact business and decisions is important for both interacting with others and anticipating potential conflicts, including those that may result in or indicate potential red flags for fraud.
This paper looks at the Japanese values relating to honesty and loyalty to show how much these ideas overlap. The lack of a conflict of values creates a risk for fraud, which will be shown through an analysis of the scandals of two Japanese companies, Toshiba and Olympus. These scandals shine light on the complexity of the ethical dilemma for the Japanese employees; since their sense of circumstantial honesty encourages them to lie if it maintains the harmony of the group, there is little stopping them from committing the fraud that their superiors asked them to commit.
In a global economy, understanding the ways that values impact business and decisions is important for both interacting with others and anticipating potential conflicts, including those that may result in or indicate potential red flags for fraud.
ContributorsTabar, Kelly Ann (Author) / Samuelson, Melissa (Thesis director) / Goldman, Alan (Committee member) / WPC Graduate Programs (Contributor) / W.P. Carey School of Business (Contributor) / School of Accountancy (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05