Browsing by Subject "sustainable"

Now showing 1 - 6 of 6
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    Green Infrastructure Systems as part of the Solution for Flooding in Panama
    (2020-12) Aizpurua Miranda, Nathaly
    This study aims to find solutions to mitigate the problem of flooding in Panama City. This was conducted in order to create a support containing Green Stormwater Infrastructures methods and proposals to guide the community towards more sustainable development. Panama has been notoriously affected by climate change, especially in terms of rainfall. There have been alterations in the rainfall regime that together with other factors such as pollution by disposals have caused serious problems of flooding in the capital city.However, there are limitations such as the lack of soil studies and non-easily accessible environmental information, among other things, which complicate the collection of information for a more in-depth study on which methods would be more feasible according to the sector. Hence, one of the areas most affected by the floods (Juan Diaz Township and Domingo Diaz Av) was chosen as a case study, thus demonstrating that despite being an already developed area, small changes can be made to generate a great impact. The paper can also be improved by collecting site-specific data, such as the percentage of evapotranspiration, more in-depth studies on types of plants that benefit green infrastructure systems, among others, but more time and money would have to be invested to obtain quick results . Future researchers can use this work as a starting point for the application of these systems in Panama.
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    Planning for a Sustainable Future: Inver Grove Heights Efficient City Fleet
    (2018) Hillstrom, Ally
    The objective of this paper is to identify actions the City of Inver Grove Heights can take to increase the fuel efficiency of their vehicle fleet, reduce fleet management costs, and reduce fleet emissions. This paper begins with an overview of the City of Inver Grove Heights existing fleet management conditions including fleet composition, expenses, emissions, and replacement process. The next section of this report reviews fleet management frameworks currently followed by government agencies. Next, fleet management case studies are presented of two local government organizations in Minnesota based on defined criteria. Each case study showcases how local government organizations have implemented fleet management practices included in the previous fleet management framework section to also achieve similar fleet management goals as defined by the City of Inver Grove Heights. Additional information regarding the organizations' fleet management policies and policy outcomes are included. Drawing from transferrable lessons learned from a literature review of government fleet management frameworks and case studies collected through interviews, best management practices and policy options are presented for the City of Inver Grove Heights updated fleet management process and are evaluated based on a cost-benefit analysis. This paper concludes with final recommendations for the City of Inver Grove Heights to increase the fuel efficiency, reduce fleet management costs, and reduce vehicle emissions based on this multi-method analysis. The Cost Benefit Analysis presented in this paper suggests that the greatest impact on all three goals could be achieved by reducing inefficient driving behavior (Fig. 16.1 through 16.4). It is recommended the City continues to collect more comprehensive vehicle use data to identify the cause of inefficient driving behaviors and to identify strategies to potentially reduce inefficient driving behavior, such as through employee education.
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    Ring-Opening Polymerization as a Platform for Tailored Polymers from Isosorbide and Other Renewable Feedstocks
    (2020-10) Saxon, Derek
    To withstand the critical need for plastics, we must innovate how polymers are constructed and deconstructed. Isosorbide and other renewable feedstocks have shown exceptional promise as replacements for commodity plastics. The work in thesis describes ring-opening polymerization as a previously unexplored strategy to synthesize polymers primarily from isosorbide, as well as several other renewable feedstocks. We describe traditional and contemporary approaches to synthesizing polymers from isosorbide along with the current challenges faced (Chapter 1). Initial efforts were aimed at developing polyethers with isosorbide in the backbone through ring-opening polymerization of an annulated isosorbide derivative, ultimately providing control over both the polymer microstructure and macromolecular architecture, enabling cyclic or linear polymers to be targeted (Chapter 2). This work is a stepping-stone for polymerization of complex heterocycles from renewable feedstocks. We then turned our focus to polycarbonate analogs to the poly(meth)acrylates previously developed in our lab (Chapter 3). Specifically, we established a method for the rapid synthesis of chemically recyclable, functional (co)polycarbonates with tailored thermal properties from isosorbide and other renewably derived alcohols. The polycarbonates were then redesigned to exploit industrial waste streams—specifically glycerol and carbon dioxide—to construct the value-added polymer backbone (Chapter 4). Tandem functionalization and ring-opening polymerization is being pursued to afford polycarbonates with 100% renewable content. These efforts may facilitate the development of commercially relevant sustainable polycarbonates with tailored properties that work toward eliminating plastic waste streams.
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    RSDP The Student Foodie newsletter - Spring 2015
    (Regional Sustainable Development Partnerships, 2015) Schwenn, Ronnie
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    Silicon quantum dot luminescent solar concentrators
    (2019-08) Hill, Samantha
    Silicon quantum dots (Si QDs) have previously been established as a unique class of quantum-confined materials with potential for a wide variety of optoelectronic applications. In this work, we examine their application to luminescent solar concentrators, or LSCs, for the first time by developing high-quality Si QD / polymer nanocomposites. By encasing Si QDs with in a polymer slab, most of their photoluminescence becomes trapped via total internal reflection and escapes only at the slab edges where solar cells can be placed to harvest the concentrated light. We find that Si QDs are suitable for such LSC devices due to their unique combination of indirect band gap absorption with efficient photoluminescence. The resulting low overlap between the absorption and photoluminescence spectra yields low reabsorption losses in large-area LSCs without the use of rare or toxic elements in the luminophore. We demonstrate effective Si QD LSC prototypes consisting of flexible and rigid bulk nanocomposites as well as films on glass using methacrylate-based polymers. We find the Si QDs maintain their optical properties throughout radically-initiated polymerization processes but are prone to forming light scattering agglomerates in the solid phase. These agglomerates drastically reduce the LSC waveguiding efficiency due to their light scattering properties. We find that light scattering from these nanocomposites increases with Si QD concentration. One approach for improving the dispersion of the Si QDs within solid polymers is to choose surface ligands which mimic the structure of the encasing polymer. We demonstrate this with ester-capped Si QDs compared to alkane-capped Si QDs in poly(methyl methacrylate), or PMMA. Furthermore, we find that fast polymer solidification rates also reduce the formation of light scattering agglomerates. We show ester-Si QD / PMMA films cast from prepolymer solutions have an order of magnitude higher concentration limit before the onset of light scattering compared to their bulk-polymerized counterparts. Overall, this work establishes Si QDs as a promising luminophore for visibly transparent LSCs which may be used in the future for solar harvesting windows and architectural elements or in concert with other LSCs to form more efficient tandem structures.
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    What Shade of "Green" is Your Event?
    (University of Minnesota Tourism Center, 2009) Gustafson, Kent