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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

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
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Description
Metal-organic frameworks (MOFs) are a new set of porous materials comprised of metals or metal clusters bonded together in a coordination system by organic linkers. They are becoming popular for gas separations due to their abilities to be tailored toward specific applications. Zirconium MOFs in particular are known for their

Metal-organic frameworks (MOFs) are a new set of porous materials comprised of metals or metal clusters bonded together in a coordination system by organic linkers. They are becoming popular for gas separations due to their abilities to be tailored toward specific applications. Zirconium MOFs in particular are known for their high stability under standard temperature and pressure due to the strength of the Zirconium-Oxygen coordination bond. However, the acid modulator needed to ensure long range order of the product also prevents complete linker deprotonation. This leads to a powder product that cannot easily be incorporated into continuous MOF membranes. This study therefore implemented a new bi-phase synthesis technique with a deprotonating agent to achieve intergrowth in UiO-66 membranes. Crystal intergrowth will allow for effective gas separations and future permeation testing. During experimentation, successful intergrown UiO-66 membranes were synthesized and characterized. The degree of intergrowth and crystal orientations varied with changing deprotonating agent concentration, modulator concentration, and ligand:modulator ratios. Further studies will focus on achieving the same results on porous substrates.
ContributorsClose, Emily Charlotte (Author) / Mu, Bin (Thesis director) / Shan, Bohan (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
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Description
Affect signals what humans care about and is involved in rational decision-making and action selection. Many technologies may be improved by the capability to recognize human affect and to respond adaptively by appropriately modifying their operation. This capability, named affect-driven self-adaptation, benefits systems as diverse as learning environments, healthcare applications,

Affect signals what humans care about and is involved in rational decision-making and action selection. Many technologies may be improved by the capability to recognize human affect and to respond adaptively by appropriately modifying their operation. This capability, named affect-driven self-adaptation, benefits systems as diverse as learning environments, healthcare applications, and video games, and indeed has the potential to improve systems that interact intimately with users across all sectors of society. The main challenge is that existing approaches to advancing affect-driven self-adaptive systems typically limit their applicability by supporting the creation of one-of-a-kind systems with hard-wired affect recognition and self-adaptation capabilities, which are brittle, costly to change, and difficult to reuse. A solution to this limitation is to leverage the development of affect-driven self-adaptive systems with a manufacturing vision.

This dissertation demonstrates how using a software product line paradigm can jumpstart the development of affect-driven self-adaptive systems with that manufacturing vision. Applying a software product line approach to the affect-driven self-adaptive domain provides a comprehensive, flexible and reusable infrastructure of components with mechanisms to monitor a user’s affect and his/her contextual interaction with a system, to detect opportunities for improvements, to select a course of action, and to effect changes. It also provides a domain-specific architecture and well-documented process guidelines, which facilitate an understanding of the organization of affect-driven self-adaptive systems and their implementation by systematically customizing the infrastructure to effectively address the particular requirements of specific systems.

The software product line approach is evaluated by applying it in the development of learning environments and video games that demonstrate the significant potential of the solution, across diverse development scenarios and applications.

The key contributions of this work include extending self-adaptive system modeling, implementing a reusable infrastructure, and leveraging the use of patterns to exploit the commonalities between systems in the affect-driven self-adaptation domain.
ContributorsGonzalez-Sanchez, Javier (Author) / Burleson, Winslow (Thesis advisor) / Collofello, James (Thesis advisor) / Garlan, David (Committee member) / Sarjoughian, Hessam S. (Committee member) / Atkinson, Robert (Committee member) / Arizona State University (Publisher)
Created2016