Matching Items (14)
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- All Subjects: chemical engineering
- All Subjects: Economics
- Creators: School of Sustainability
- Member of: Barrett, The Honors College Thesis/Creative Project Collection
Description
South Mountain is the largest municipal park in the nation. It is a bundled amenity, providing a series of linked services to the surrounding communities. A dataset of 19,209 homes in 155 neighborhoods within three miles of the park was utilized in order to complete a hedonic estimation for two nearby urban villages, Ahwatukee Foothills and South Mountain Village. Measures of access include proximity to the park, trailhead access, and adjacency to the park. Two regressions were estimated, the first including lot characteristics and subdivision fixed effects and the second using the coefficients for each subdivision as the dependent variable. These estimates describe how the location of a house in a subdivision contributes to its conditional mean price. As a result they offer a direct basis for capturing amenities measured at the neighborhood scale on home values. Park proximity, trailhead access and adjacency were found to significantly influence the price of homes at the 5% confidence level in Ahwatukee, but not in South Mountain Village. The results of this study can be applied to issues of environmental justice and park access in determining which areas and attributes of the park are associated with a high premium. Though South Mountain was preserved some time ago, development and future preservation in the City of Phoenix can be informed by such studies.
ContributorsRamakrishna, Saritha Kambhampati (Author) / Abbott, Joshua (Thesis director) / Smith, V. Kerry (Committee member) / Schoon, Michael (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / Economics Program in CLAS (Contributor) / Department of English (Contributor)
Created2015-05
Description
This thesis looks at the theory and empirical evidence that surrounds the debate between environmentalists and economists regarding the link between trade liberalization and environmental degradation. The main points of the theory are the scale, composition, and technique effects which, when aggregated, are ambiguous as the harm or benefit of trade's effect on the environment. The empirical evidence studied ranges in time periods from the early 1990s to 2011 and mainly focuses on the existence or absence of an environmental Kuznets curve for certain pollutant. However, the data still proves to be inconclusive. The debate about the possible link between trade and the environment is as important as ever, especially in regards to carbon dioxide emissions. Going forward, it is extremely important that international cooperation regarding emissions targets and abatement goals increases. Trade will prove to be an invaluable tool in this endeavor as it provides a mechanism for the spread of green technology as well as can be used as a method of environmental policy enforcement.
ContributorsCotterell, Emily Claire (Author) / Mendez, Jose (Thesis director) / McDaniel, Cara (Committee member) / School of Sustainability (Contributor) / Department of Economics (Contributor) / Department of Supply Chain Management (Contributor) / W. P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Improvement in carbon capture percentage was calculated as most effective in 10 mg/L-MEA BG-11 media, with improvement in carbon capture of 1.012% over the control. In studying the effect of agitation at 150 revolutions-per-minute (RPM) with a magnetic stir bar, it was found that mass transfer actually decreased. Future investigations are warranted to fully characterize the effect of different alkanolamine types, concentrations, and mixing regimens on mass transfer of CO2. In this thesis, emphasis was placed on experimental setup to allow for a discussion of the unexpected characteristics of the findings of the mass transfer experiments. Understanding the effect of experimental setup on mass transfer will be important in designing more effective methods of CO2 absorption for improving growth of cyanobacteria.
ContributorsMcallister, Cameron William (Author) / Nielsen, David (Thesis director) / Nannenga, Brent (Committee member) / School of Sustainability (Contributor) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Membrane-based technology for gas separations is currently at an emerging stage of advancement and adoption for environmental and industrial applications due to its substantial advantages like lower energy and operating costs over the conventional gas separation technologies. Unfortunately, the available polymeric (or organic) membranes suffer a trade-off between permeance and selectivity. Mixed matrix membranes (MMMs) containing two-dimensional (2D) metal-organic frameworks (MOFs) as fillers are a highly sought approach to redress this trade-off given their enhanced gas permeabilities and selectivities compared to the pure polymeric membrane. These MMMs are increasingly gaining attention by researchers due to their unique properties and wide small- and large-scale gas separation applications. However, straightforward and scalable methods for the synthesis of MOFs nanosheets have thus far been persistently elusive. This study reports the single-phase preparation, and characterization of MMMs with 2D MOFs nanosheets as fillers. The prepared MOF and the polymer matrix form the ‘dense’ MMMs which exhibit increased gas diffusion resistance, and thus improved separation abilities. The single-phase approach was more successful than the bi-phase at synthesizing the MOFs. The influence of sonication power and time on the characteristics and performance of the membranes are examined and discussed. Increasing the sonication power from 50% to 100% reduces the pore size. Additionally, the ultimate effect on the selectivity and permeance of the MMMs with different single gases is reported. Analysis of results with various gas mixers indicates further performance improvements in these MMMs could be achieved by increasing sonication time and tuning suitable membrane thicknesses. Reported results reveal that MMMs are excellent candidates for next-generation gas mixture separations, with potential applications in CO2 capture and storage, hydrogen recovery, alkene recovery from alkanes, and natural gas purification.
ContributorsNkuutu, John (Author) / Mu, Bin (Thesis director) / Shan, Bohan (Committee member) / Chemical Engineering Program (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Optimizing cathodes for microbial fuel cells is important to maximize energy harvested from wastewater. Cathodes were made by modifying a recipe from previous literature and testing the current of the cathode using linear sweep voltammetry. The cathodes contained an Fe-N-C catalyst combined with a Polytetrafluoroethylene binder. Optimizing the power resulting from the microbial fuel cells will help MFCs be an alternative energy source to fossil fuels. The new cathodes did improve in current production from −16 𝐴/𝑚 to −37 𝐴/𝑚 at -0.4 V. When fitted using a Butler-Volmer model, the cathode linear-sweep voltammograms did not follow the expected exponential trend. These results show a need for more research on the cathodes and the Butler-Volmer model, and they also show that the cathode is ready for further and longer application in a microbial fuel cell.
ContributorsRussell, Andrea Christine (Author) / Torres, Cesar (Thesis director) / Young, Michelle (Committee member) / School of Sustainable Engineering & Built Envirnmt (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
This paper analyzes responses to a survey using a modified fourfold pattern of preference to determine if implicit information, once made explicit, is practically significant in nudging irrational decision makers towards more rational decisions. Respondents chose between two scenarios and an option for indifference for each of the four questions from the fourfold pattern with expected value being implicit information. Then respondents were asked familiarity with expected value and given the same four questions again but with the expected value for each scenario then explicitly given. Respondents were asked to give feedback if their answers had changed and if the addition of the explicit information was the reason for that change. Results found the addition of the explicit information in the form of expected value to be practically significant with ~90% of respondents who changed their answers giving that for the reason. In the implicit section of the survey, three out of four of the questions had a response majority of lower expected value answers given compared to the alternative. In the explicit section of the survey, all four questions achieved a response majority of higher expected value answers given compared to the alternative. In moving from the implicit to the explicit section, for each question, the scenario with lower expected value experienced a decrease in percentage of responses, and the scenario with higher expected value and indifference between the scenarios both experienced an increase in percentage of responses.
ContributorsJohnson, Matthew (Author) / Goegan, Brian (Thesis director) / Foster, William (Committee member) / School of Sustainability (Contributor) / Economics Program in CLAS (Contributor) / Dean, W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Is nuclear power sustainable when compared to other energy sources? A truly sustainable energy source provides an environmental benefit, minimizes costs to consumers both socially and economically, and continues to do so in both the short and the long term. Taking the zero-carbon nature of nuclear generation as its net environmental benefit, this paper the evaluates the economic and social costs of nuclear power to determine if nuclear power's reputation as "unsustainable" is warranted. The sustainability of nuclear power is evaluated in two main categories. The first part focuses on the economics of nuclear power. There are many preconceived notions regarding nuclear power and its associated industry. This section addresses those notions to determine their validity given recent data. The prevalent types of nuclear plants across the U.S., the economics of the stages of nuclear energy production, and its competitiveness relative to other energy sources are addressed, culminating in an evaluation of its modern economic attractiveness as well as its future economic viability. A sustainability assessment would not be complete without addressing the social costs of an energy source, as a sustainable source must be both economically and socially viable. If it can be established that nuclear power can provide energy at lower rates and at a lower cost in terms of externalities, then it would be considered truly sustainable. To investigate those externalities, the second part of the analysis focuses on the human costs associated with the various stages of nuclear energy production. Those costs are then compared to those of alternatives sources of power, and selected case studies are examined to illustrate the ultimate risks associated with nuclear power operations. By quantifying these aspects and comparing the results to alternatives in the field, a better understanding of nuclear energy technology and its potential is achieved. The reader can then ascertain whether nuclear power's reputation as being "unsustainable" is, or is not, a reputation it deserves.
ContributorsRudolph, Alexander James (Author) / Miller, Clark (Thesis director) / Richter, Jennifer (Committee member) / School of Sustainability (Contributor) / School of Politics and Global Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Existing research into the health benefits of insurance fall into two major categories \u2014 observational and experimental. Observational studies have centered on data sets from before 2000 and focus on the mortality differences between the privately insured and the uninsured. Experimental studies began with Massachusetts' 2006 health reform and continued after the passage of the Affordable Care Act. These studies measure the effects of public insurance among the coverage expansion populations. These two bodies of literature come to ambiguous and contradictory conclusions to the mortality effects and health value of insurance. This study extends the observational methodologies to the publicly insured in samples from the National Health and Nutrition Examination Survey in both the 1988-1994 survey and the 2001-2002 survey. Using the Cox Proportional Hazard model, this study estimates the hazard ratios faced by the privately and publicly insured compared to the uninsured. This study finds the publicly insured face hazards 1.5 times those of the uninsured (p<.001), while the privately insured do not face hazards significantly different from those of the uninsured. Literature suggests that some unobserved characteristic of the publicly insured are influencing their mortality. Interacting with participants health reveals that these differences across groups shrink as health declines. Experimental literature suggests that public insurance lowers the uninsured risk from "healthcare amenable" conditions. Treatment of these conditions may explain the hazard reductions among the uninsured in non-excellent health. The high risk of the publicly insured in excellent health defies explanation.
ContributorsMorita, Aidan James Donnelly (Author) / Veramendi, Gregory (Thesis director) / Zafar, Basit (Committee member) / School of Mathematical and Statistical Sciences (Contributor) / Economics Program in CLAS (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Anaerobic digestion (AD), a common process in wastewater treatment plants, is traditionally assessed with Biochemical Methane Potential (BMP) tests. Hydrolysis is considered its rate-limiting step. During my research, I assessed the impact of pretreatment on BMPs and microbial electrochemical cells (MECs). In the first set of experiments, BMP tests were performed using alkaline and thermal pretreated waste activated sludge (WAS), a control group, and a negative control group as samples and AD sludge (ADS) as inoculum. The data obtained suggested that BMPs do not necessarily require ADS, since samples without inoculum produced 5-20% more CH4. However, ADS appears to reduce the initial methanogenesis lag in BMPs, as no pH inhibition and immediate CH4 production were observed. Consumption rate constants, which are related to hydrolysis, were calculated using three methods based on CH4 production, SSCOD concentration, and the sum of both, called the lumped parameter. All the values observed were within literature values, yet each provide a different picture of what is happening in the system. For the second set of experiments, the current production of 3 H-type MECs were compared to the CH4 production of BMPs to assess WAS solids' biodegradability and consumption rates relative to the pretreatment methods employed for their substrate. BMPs fed with pretreated and control WAS solids were performed at 0.42 and 1.42 WAS-to-ADS ratios. An initial CH4 production lag of about 12 days was observed in the BMP assays, but MECs immediately began producing current. When compared in terms of COD, MECs produced more current than the BMPs produced CH4, indicating that the MEC may be capable of consuming different types of substrate and potentially overestimating CH4 production in anaerobic digesters. I also observed 2 to 3 different consumption events in MECs versus 3 for BMP assays, but these had similar magnitudes, durations, and starting times in the control and thermal pretreated WAS-fed assays and not in alkaline assays. This might indicate that MECs identified the differences of alkaline pretreatment, but not between control WAS and thermal pretreated WAS. Furthermore, HPLC results suggest at least one hydrolysis event, as valerate, butyrate, and traces of acetate are observed in the reactors' effluents. Moreover, a possible inhibition of valerate-fixing microbial communities due to pretreatment and the impossibility of valerate consumption by ARB might explain its presence in the reactors' effluents.
ContributorsBrown Munoz, Francisco (Author) / Torres, Cesar (Thesis director) / Rittmann, Bruce E. (Committee member) / Chemical Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The objective of this research study is to assess the effectiveness of a poster-based messaging campaign and engineering-based activities for middle school and high school students to encourage students to explore and to pursue chemical engineering. Additionally, presentations are incorporated into both methods to provide context and improve understanding of the presented poster material or activity. Pre-assessments and post-assessments are the quantitative method of measuring effectiveness. For the poster campaign, ASU juniors and seniors participated in the poster campaign by producing socially relevant messages about their research or aspirations to address relevant chemical engineering problems. For the engineering-based activity, high school students participated in an Ira A. Fulton Schools of Engineering program "Young Engineers Shape the World" in which the students participated in six-hour event learning about four engineering disciplines, and the chemical engineering presentation and activity was conducted in one of the sessions. Pre-assessments were given at the beginning of the event, and the post-assessments were provided towards the end of the event. This honors thesis project will analyze the collected data.
ContributorsBueno, Daniel Tolentino (Author) / Ganesh, Tirupalavanam (Thesis director) / Parker, Hope (Committee member) / Chemical Engineering Program (Contributor) / School of Historical, Philosophical and Religious Studies (Contributor) / W. P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05