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Aortic heart valve calcification shows in the deposition of calcium phosphate minerals in the leaflets of aortic heart valves. This stiffens the leaflets and eventually leads to heart failure. Male sex, diabetes, and chronic kidney disease increase the chance to develop the condition. The only treatment for aortic heart valve calcification is surgical or transcatheter heart valve replacement because the disease mechanisms remain poorly understood. For example, our group was only recently able to show that heart valve calcification manifests itself differently in men and women. However, the effect of different underlying diseases on the physicochemical manifestation of aortic heart valve calcification are completely unknown. Understanding how different diseases affect heart valve calcification might help to develop new methods to detect and treat the disease.

In this summer project you will study human heart valve samples with advanced materials characterization techniques, such as e.g. scanning electron microscopy, energy-dispersive X-ray spectroscopy, Raman spectroscopy, and Fourier transform-infrared spectroscopy to understand whether and how underlying diseases affects the physicochemical properties (elemental composition, crystallinity, morphology, phases, …) of aortic heart valve calcifications. If time allows, you will also prepare collagen-based gels as laboratory models of the process of heart valve calcification.
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Conduct literature review
Perform experiments detailed above on heart valves
Possibly work on collagen gel synthesis and characterization

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Graphene oxide (GO) is an oxidized form of graphene, a bidimensional carbon based nanomaterial. When GO flakes stack on top of each other to form membranes, they create nano-sized channels between each layer, through which water easily goes through, but larger molecules may be blocked especially if the GO membrane is doped with specific ions.
In this project we will attempt to prepare the first ever GO membrane whose channel size can be tuned depending on pH or other stimuli. To achieve this, we will intercalate in between the GO layers molecules whose configuration changes according to the desired stimulus. We will then characterize how the channel spacing changes in the presence of the stimulus, and if the flow of different molecules through the membranes is restricted.
If successful, this work will showcase tunable GO membranes, which could be applied in a variety of fields to allow passage of molecules on-demand; an example is the release of fertilizers or metal chelators in the field as a function of changes in pH or ionic concentration of terrain, towards more sustainable agricultural practices.

Conduct literature review
Prepare GO membranes with and without shape-changing molecules
Characterize membranes with XRD, IR, Raman, SEM, contact angle.
Perform filtration tests

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Low-temperature electrolysis of iron ores in aqueous caustic solutions is a novel technology aimed at replacing the traditional high-temperature blast furnaces that are responsible for heavy CO2 emissions. In this project, the undergraduate student will be working closely with graduate students in our laboratory carrying out batch or continuous benchtop electrolysis tests, characterizing the reacting iron oxide particles as well as the metallic iron deposit.

The student will operate batch and continuous electrochemical reactors and run the associated power supplies and data acquisition multimeters to acquire experimental electrolysis data over time. They will also use XRD, SEM, MP-AES, PSD, differential leaching, and other analytical techniques for detailed analysis, and combine experimental data with thermodynamic models in OLI software, MATLAB, and python for improved process predictions.

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Life cycle assessment (LCA) is used to quantify environmental impacts of large-scale deployment of batteries from materials extraction through waste disposal, including mining waste, in support of designing solutions for superior environmental outcomes. By mass, batteries presently comprise approximately 7% cobalt, 7% lithium carbonate equivalent, 4% nickel, 5% manganese, 10% copper, 15% aluminum, 16% graphite, and 36% other materials. It is estimated in the United States that 15%-18% of cobalt, 9%-11% of lithium, and 15%-17% of nickel demand in 2035 could be met by closed-loop recycling. Such options have yet to robustly include mining operations that will be required for the new battery demand. Moreover, new battery designs will likely have better performance, impacting the environment and as well as the mining economy. Such solutions may come at a cost. Techno-economic analysis (TEA) an important tool to evaluate the economic performance of technologies across innovation stages can quantify such costs. In this position, a student will examine the forefront of knowledge in LCA-TEA of batteries in collaboration with a graduate student, and professors in the Departments of Mining and Materials Engineering, Civil Engineering, and Chemistry. The collaborating research groups include Mining Systems Dynamics (Prof. Navarra), the Energy Technology And Policy Assessment (ETAPA) research group (Prof. Jordaan) and the McCalla Lab (Prof. McCalla). The idea is to determine how LCAs of batteries can be improved but also to make recommendations about what emerging technologies should be better informed by LCA and TEA.

-Critique present modeling of mining operations within life cycle assessments of battery technologies and their supporting databases.
-Identifying key emerging battery technologies that hold promise to reduce impacts, including consideration of mining impacts
-Conducting a literature review to determine whether LCAs have been completed on these technologies.

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