Matching Items (29)
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- All Subjects: Membranes
- All Subjects: Business
- Creators: Chemical Engineering Program
- Creators: School of International Letters and Cultures
- Member of: Barrett, The Honors College Thesis/Creative Project Collection
Description
Within recent years, metal-organic frameworks, or MOF’s, have gained a lot of attention in the materials research community. These micro-porous materials are constructed of a metal oxide core and organic linkers, and have a wide-variety of applications due to their extensive material characteristic possibilities. The focus of this study is the MOF-5 material, specifically its chemical stability in air. The MOF-5 material has a large pore size of 8 Å, and aperture sizes of 15 and 12 Å. The pore size, pore functionality, and physically stable structure makes MOF-5 a desirable material. MOF-5 holds applications in gas/liquid separation, catalysis, and gas storage. The main problem with the MOF-5 material, however, is its instability in atmospheric air. This inherent instability is due to the water in air binding to the zinc-oxide core, effectively changing the material and its structure. Because of this material weakness, the MOF-5 material is difficult to be utilized in industrial applications. Through the research efforts proposed by this study, the stability of the MOF-5 powder and membrane were studied. MOF-5 powder and a MOF-5 membrane were synthesized and characterized using XRD analysis. In an attempt to improve the stability of MOF-5 in air, methyl groups were added to the organic linker in order to hinder the interaction of water with the Zn4O core. This was done by replacing the terepthalic acid organic linker with 2,5-dimethyl terephthalic acid in the powder and membrane synthesis steps. The methyl-modified MOF-5 powder was found to be stable after several days of exposure to air while the MOF-5 powder exhibited significant crystalline change. The methyl-modified membrane was found to be unstable when synthesized using the same procedure as the MOF-5 membrane.
ContributorsAnderson, Anthony David (Author) / Lin, Jerry Y.S. (Thesis director) / Ibrahim, Amr (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Industry is changing. Businesses are plagued with problems of inefficiency, ineffectiveness, and waste. Many of these issues arise from some common mistakes within established management structures; these issues include lack of expertise in leadership positions, lack of unity across the organization, and imbalance within the business. Using Information Measurement Theory, the Kashiwagi Solution Model, and leadership theories, this thesis presents a simple approach to creating a business structure through explaining the basic tenets of a successful modern business. It was determined that the first and most important task of a business is to set realistic long-term goals for the organization. This thesis proposes that the basic needs of a successful business also includes having the right individuals, team formation, positive leadership, and the proper alignment of resources. It was found that it is best to hire individuals that exhibit some Type A characteristics because those individuals are likely to effectively carry out the goals of the business. Forming these individuals into small teams increases their processing speeds and encourages a balance of accountability, innovative solutions, and a network of learning. Furthermore, consistent, positive leadership that lives the company culture is a key element to successfully maintaining the business vision and maximizing associate effectiveness. It was also determined that aligning the organization to work towards the business vision can be performed through implementing a flat structure, placing individuals in roles that maximize effectiveness, and establishing the right business goals so that there is a consistent business vision at all levels of the organization. This thesis also provides guidance on how to implement these tenets in a simple, dominant way. Ultimately, the four proposed tenets working in unison towards business goals can lead to a successful and adaptable modern business.
ContributorsMeade, Payton Drew (Author) / Kashiwagi, Dean (Thesis director) / Kashiwagi, Jacob (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Sex trafficking in the United States is an enormous illegal underground business economy that involves the sexual exploitation of many persons. Due to the large nature of the sex trafficking business and the many different types of sex trafficking, it is helpful for social workers, government agencies, and activists to understand the intricacies of the various types of sex trafficking. This research focused on determining the human resources business structures behind pimp businesses that relied on mental coercion of the victim. The data source used, Pimpfeet.com—an online pimp authored blog—provided data from actual pimps on their business practices that were analyzed to determine trends in recruitment and retention. These trends were compared to human resource management theories from business literature to determine to what extent, or if at all, a pimp’s business recruited and retained workers in a way that was similar to how a legal business would, according to human resources strategies. The data extracted from Pimpfeet.com and used in this study consisted of 69 pimp quotes that were put into three recruitment categories and five retention categories based on human resource management literature in order to see which categories were used for recruitment and retention by pimps. This study found that pimp recruitment and retention followed, to some extent, the same models described in the human resource management literature, with slight modifications. This study showed that job embeddedness theory (Holtom, Mitchel and Lee, 2009) was able to explain much of why sex trafficking victims are retained so well by pimps since they are so embedded in the prostitution lifestyle. These findings show the different business techniques that pimps use for recruitment and retention of sex workers and are useful for understanding how a social worker, government entity or an activist can combat these forces to help remove victims from a pimp’s control, or keep victims from getting recruited in the first place. Further areas of research related to this topic were suggested.
ContributorsRivera, Kameron (Co-author) / La Benz, Alexis (Co-author) / Roe-Sepowitz, Dominique (Thesis director) / Corley, Kevin (Committee member) / W. P. Carey School of Business (Contributor) / Chemical Engineering Program (Contributor) / T. Denny Sanford School of Social and Family Dynamics (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Due to the environmental problems caused by global warming, it has become necessary to reduce greenhouse gas emissions across the planet. Biofuels, such as ethanol, have proven to release cleaner emissions when combusted. However, large scale production of these alcohols is uneconomical and inefficient due to limitations in standard separation processes, the most common being distillation. Pervaporation is a novel separation technique that utilizes a specialized membrane to separate multicomponent solutions. In this research project, pervaporation utilizing ZIF-71/PDMS mixed matrix membranes are investigated to see their ability to recover ethanol from an ethanol/aqueous separation. Membranes with varying nanoparticle concentrations were created and their performances were analyzed. While the final results indicate that no correlation exists between nanoparticle weight percentage and selectivity, this technology is still a promising avenue for biofuel production. Future work will be conducted to improve this existing process and enhance membrane selectivity.
ContributorsHoward, Chelsea Elizabeth (Author) / Lind, Mary Laura (Thesis director) / Nielsen, David (Committee member) / Greenlee, Lauren (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor) / Materials Science and Engineering Program (Contributor)
Created2015-05
Description
The rationale behind this thesis is grounded in nearly two years of experience interning at UTC Aerospace Systems (UTAS). I was able to gain a wide exposure to different facets of the supply chain management organization during my time as an intern, from strategic sourcing and commodity management, to tactical procurement and supplier development. In each of these respective areas, I observed a variety of initiatives that did not reach their full potential because employees were not provided the tools for success. One of these areas in particular is the New Product Introduction (NPI) process management, in which there is not a standard process for program managers to follow from start to finish. I saw this as an opportunity to hone in the scope of my thesis research and experience at UTAS to improve a process and provide standard work and tools for it to be consistently executed. The current state process is not formalized \u2014 it merely tracks certain metrics that are not necessarily applicable to the overall health of the program because they do not monitor the progress of the program. This resulted in heavy costs incurred from inadequate planning, a skewed timeline, and customer frustration. The aim of the desired state NPI process is to gather cross-functional expertise and weigh in, adhere to a strict entry to market timeline, and increase customer satisfaction, all while minimizing costs incurred throughout the life of the program. The dominant output of this project will be a cross-functional flow chart of the process for each group to follow and standard work and tools to support the process across a variety of NPI program applications.
ContributorsThorn, Taylor Aiko Marie (Author) / Brown, Steven (Thesis director) / Arrigoni, Gregory (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / Department of Supply Chain Management (Contributor) / W. P. Carey School of Business (Contributor)
Created2015-05
Description
The goal of this research project is to create a mixed matrix membrane that can withstand very acidic environments but still be used to purify water. The ultimate goal of this membrane is to be used to purify urine both here on Earth and in space. The membrane would be able to withstand these harsh conditions due the incorporation of a resilient impermeable polymer layer that will be cast above the lower hydrophilic layer. Nanoparticles called zeolites will act as a water selective pathway through this impermeable layer and allow water to flow through the membrane. This membrane will be made using a variety of methods and polymers to determine both the cheapest and most effective way of creating this chemical resistant membrane. If this research is successful, many more water sources can be tapped since the membranes will be able to withstand hard conditions. This document is primarily focused on our progress on the development of a highly permeable polymer-zeolite film that makes up the bottom layer of the membrane. Multiple types of casting methods were investigated and it was determined that spin coating at 4000 rpm was the most effective. Based on a literature review, we selected silicalite-1 zeolites as the water-selective nanoparticle component dispersed in a casting solution of polyacrylonitrile in N-methylpyrrolidinone to comprise this hydrophilic layer. We varied the casting conditions of several simple solution-casting methods to produce thin films on the porous substrate with optimal film properties for our membrane design. We then cast this solution on other types of support materials that are more flexible and inexpensive to determine which combination resulted in the thinnest and most permeable film.
ContributorsHerrera, Sofia Carolina (Author) / Lind, Mary Laura (Thesis director) / Khosravi, Afsaneh (Committee member) / Hestekin, Jamie (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor)
Created2015-05
Description
The recovery of biofuels permits renewable alternatives to present day fossil fuels that cause devastating effects on the planet. Pervaporation is a separation process that shows promise for the separation of ethanol from biologically fermentation broths. The performance of thin film composite membranes of polydimethylsiloxane (PDMS) and zeolite imidazolate frameworks (ZIF-71) dip coated onto a porous substrate are analyzed. Pervaporation performance factors of flux, separation factor and selectivity are measured for varying ZIF-71 loadings of pure PDMS, 5 wt%, 12.5 wt% and 25 wt% at 60 oC with a 2 wt% ethanol/water feed. The increase in ZIF-71 loadings increased the performance of PDMS to produce higher flux, higher separation factor and high selectivity than pure polymeric films.
ContributorsLau, Ching Yan (Author) / Lind, Mary Laura (Thesis director) / Durgun, Pinar Cay (Committee member) / Lively, Ryan (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / Chemical Engineering Program (Contributor)
Created2014-05
Description
In this research, construction of a model membrane system using Polyvinylidene Chloride-Co Acrylonitrile and Linde Type A zeolites is described. The systems aims to separate out flow through zeolite pores and flow through interfaces between zeolites and polymers through the use of pore filled and pore open zeolites. Permeation tests and salt rejection tests were performed, and the data analyzed to yield approximation of separated flow through zeolites and interfaces. This work concludes the more work is required to bring the model system into a functioning state. New polymer selections and new techniques to produce the membrane system are described for future work.
ContributorsShabilla, Andrew Daniel (Author) / Lind, Mary Laura (Thesis director) / Lin, Jerry (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor)
Created2014-05
Description
This thesis aims to evaluate how in classroom demonstrations compare to regular education techniques, and how student learning styles affect interest in science and engineering as future fields of study. Science education varies between classrooms, but usually is geared towards lecture and preparation for standardized exams without concern for student interest or enjoyment.5 To discover the effectiveness of demonstrations in these concerns, an in classroom demonstration with a water filtration experiment was accompanied by several modules and followed by a short survey. Hypotheses tested included that students would enjoy the demonstration more than a typical class session, and that of these students, those with more visual or tactile learning styles would identify with science or engineering as a possible major in college. The survey results affirmed the first hypothesis, but disproved the second hypothesis; thus illustrating that demonstrations are enjoyable, and beneficial for sparking or maintaining student interest in science across all types of students.
ContributorsPiper, Jessica Marie (Author) / Lind, Mary Laura (Thesis director) / Montoya-Gonzales, Roxanna (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / Chemical Engineering Program (Contributor)
Created2014-05
Description
This study details the construction and operation of a dry-jet wet spinning apparatus for extruding hollow fiber membranes (HFMs). The main components of the apparatus are a spinneret, a coagulation bath, and an automatic collection reel. Continuous fiber formation was achieved using two syringe pumps simultaneously delivering polymer dope and bore fluid to the spinneret. Based on apparatus runs performed with Polysulfone (PSF) dopes dissolved in N,N-Dimethylacetamide and supporting rheological analysis, the entanglement concentration, ce, was identified as a minimum processing threshold for creating HFMs. Similarly, significant increases in the ultimate tensile strength, fracture strain, and Young's modulus for extruded HFMs were observed as polymer dope concentration was increased at levels near ce. Beyond this initial increase, subsequent tests at higher PSF concentrations yielded diminishing changes in mechanical properties, suggesting an asymptotic approach to a point where the trend would cease. Without further research, it is theorized that this point falls on a transition from the semidiute entangled to concentrated concentration regimes. SEM imaging of samples revealed the formation of grooved structures on the inner surface of samples, which was determined to be a result of the low flowrate and polymer dope concentrations used in processing the HFMs during apparatus runs. Based on continued operation of the preliminary apparatus design, many areas of improvement were noted. Namely, these consisted of controlling the collector speed, eliminating rubbing of nascent fibers against the edge of the coagulation bath by installing an elevated roller, and replacing tygon tubing for the polymer line with a luer lock adapter for direct syringe attachment to the spinneret.
ContributorsBridge, Alexander Thomas (Author) / Green, Matthew D. (Thesis director) / Lin, Jerry Y. S. (Committee member) / School of Mathematical and Statistical Sciences (Contributor) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05