Matching Items (3)
Filtering by
- Creators: Arts, Media and Engineering Sch T
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
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
Description
As the prevalence of augmented reality (AR) technology continues to increase, so too have methods for improving the appearance and behavior of computer-generated objects. This is especially significant as AR applications now expand to territories outside of the entertainment sphere and can be utilized for numerous purposes encompassing but not limited to education, specialized occupational training, retail & online shopping, design, marketing, and manufacturing. Due to the nature of AR technology, where computer-generated objects are being placed into a real-world environment, a decision has to be made regarding the visual connection between the tangible and the intangible. Should the objects blend seamlessly into their environment or purposefully stand out? It is not purely a stylistic choice. A developer must consider how their application will be used — in many instances an optimal user experience is facilitated by mimicking the real world as closely as possible; even simpler applications, such as those built primarily for mobile devices, can benefit from realistic AR. The struggle here lies in creating an immersive user experience that is not reliant on computationally-expensive graphics or heavy-duty models. The research contained in this thesis provides several ways for achieving photorealistic rendering in AR applications using a range of techniques, all of which are supported on mobile devices. These methods can be employed within the Unity Game Engine and incorporate shaders, render pipelines, node-based editors, post-processing, and light estimation.
ContributorsSchanberger, Schuyler Catherine (Author) / LiKamWa, Robert (Thesis director) / Jayasuriya, Suren (Committee member) / Arts, Media and Engineering Sch T (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05