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Supported Liquid Metal Membranes for Hydrogen SeparationYen, Pei-Shan 25 April 2016 (has links)
Hydrogen (H2) and fuel cells applications are central to the realization of a global hydrogen economy. In this scenario, H2 may be produced from renewable biofuels via steam reforming and by solar powered water electrolysis. The purification required for fuel cell grade H2, whether in tandem or in situ within a catalytic reformer operating at 500 oC or above, would be greatly facilitated by the availability a cheaper and more robust option to palladium (Pd) dense metal membrane, currently the leading candidate. Here we describe our results on the feasibility of a completely novel membrane for hydrogen separation: Sandwiched Liquid Metal Membrane, or SLiMM, comprising of a low-melting, non-precious metal (e.g., Sn, In, Ga) film held between two porous substrates. Gallium was selected for this feasibility study to prove of the concept of SLiMM. It is molten at essentially room temperature, is non-toxic, and is much cheaper and more abundant than Pd. Our experimental and theoretical results indicate that the Ga SLiMM at 500 oC has a permeability 35 times higher than Pd, and substantially exceeds the 2015 DOE target for dense metal membranes. For developing a fundamental understanding of the thermodynamics and transport in liquid metals, a Pauling Bond Valence-Modified Morse Potential (PBV-MMP) model was developed. Based on little input, the PBV-MPP model accurately predicts liquid metal self-diffusion, viscosity, surface tension, as well as thermodynamic and energetic properties of hydrogen solution and diffusion in a liquid metal such as heat of dissociative adsorption, heat of solution, and activation energy of diffusion. The concept of SLiMM proved here opens up avenues for development practical H2 membranes, For this, improving the physical stability of the membrane is a key goal. Consequently, a thermodynamic theory was developed to better understand the change in liquid metal surface tension and contact angle as a function of temperature, pressure and gas-phase composition.
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Integrate and Assess: Information Literacy as Quality Enhancement of Undergraduate CurriculumSmith, Philip A. 01 January 2016 (has links)
This article is an account of how one small liberal arts university undertook a large scale curriculum integration and assessment project under the auspices of a Quality Enhancement Plan (QEP). After a review of relevant literature, the integration and assessment process is outlined, and the assessment data is analyzed and discussed. The integration used a tiered approach, attempting to engage students with significant IL experiences first at the lower general education level, then subsequently at the upper level in their disciplinary context. Assessment tools include widely used standardized tests and surveys as well as locally developed rubrics and surveys. While the plan satisfied the reaccreditation requirements, this is a case study and not a template; many factors would make it difficult to generalize the assessment results. More useful to IL advocates and other institutions may be the overall approach of this QEP, which aimed to be thorough enough to align with regional and national standards yet flexible enough to meet local needs.
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Modifying Some Iterative Methods for Solving Quadratic Eigenvalue ProblemsAli, Ali Hasan January 2017 (has links)
No description available.
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