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Feasibility study on large-scale geologic carbon sequestration in Southern Colorado
No full textThis study evaluates the feasibility of storing over 50 million metric tons of CO2 within a 30-year period in southern Colorado. The target for injection is the 7000 ft (2134 m)-deep Lyons saline aquifer formation, with the overlying alternating layers of anhydrite and shale serving as seals. Geological static models were constructed using seismic, well log and core data, followed by fluid flow modeling to understand the CO2 injection strategy, saturation distribution and plume size. The results indicate that approximately 60 million metric tons of CO2 can be injected with 2 wells into the formation over 30 years, with 85 % of the CO2 existing in a supercritical phase during the injection stage. After 70 years of shut-in, about 30 % of the injected CO2 becomes immobilized due to hysteresis. Seismic data shows no faulting within the injection and seal formations, and no legacy wells penetrate the Lyons formation within the study area, which reduces the risks of fault slippage and leakage through legacy wells. However, the small dip angle of the structure may present challenges to CO2 plume containment, highlighting the importance of implementing strategies such as enhanced monitoring systems, detailed geomechanical modeling, and plume migration simulations to mitigate and better understand potential risks. This study offers early insights into CCUS potential in southern Colorado using seismic and limited data, and will ultimately provide valuable guidance for future implementation of CO₂ injection in the region
All-Plastic Supercapacitors from Poly(ethylene terephthalate) Waste
No full textThe increased accumulation of plastic waste presents a major environmental challenge, underscoring the urgent need for sustainable upcycling strategies. In this work, we report the first approach for utilizing plastic waste for the fabrication of an all-plastic supercapacitor. Specifically, waste poly(ethylene terephthalate) (PET) bottles were employed not only as separators but also as precursors for porous carbon electrodes. The PET waste was converted into porous carbon for the electrodes using Ca(OH)2to assist pyrolysis and KOH for final activation. Electrochemical characterization showed that surface area governs capacitance at low current densities, whereas meso/macroporosity improves ion diffusion and enhances high-rate performance. The resulting all-plastic supercapacitor delivered a gravimetric capacitance of 197.2 F/g at 0.5 A/g and retained 79% of its capacitance at high rates, outperforming analogous devices based on glass fiber separator (190.3 F/g at 0.5 A/g). Moreover, the PET separator exhibited excellent mechanical strength (57 MPa), superior thermal resistance, and tunable ionic conductivity (up to 2.79 × 10–2S/cm) with increased porosity, demonstrating its wide suitability for supercapacitor applications. This study offers a comprehensive and scalable strategy for valorizing plastic waste into high-performance supercapacitor components, opening new opportunities for circular energy storage technologies
Plants as partners: honoring the personhood of Manoomin in research, restoration, and education
No full textAcross the Great Lakes region, Manoomin (wild rice) provides sustenance for Indigenous Peoples, yet has been in decline since the onset of Euro-American colonization. The Anishinaabe (a large group of Indigenous peoples, Great Lakes, North America) collaborate with Manoomin, university scientists, and others to inform research, restoration, and education to protect this sacred relative. We engaged Anishinaabe Ecological Knowledge to conceptualize these interspecies collaborations through an Ojibwe (an Anishinaabe people) Medicine Wheel: four foundational directions that begin in the east where the sun rises and moving-clockwise around the circle—Anishinaabeg (original people), Gidinawemaaganimin (all our relations), Aki (earth, land, and ground), and Manoomin—each with a role in Manoomin’s Mino-bimaadiziwin (wild rice’s good life). The Manoomin Medicine Wheel framework serves as a guiding example of how Indigenous worldviews can offer pathways for repairing our relationships with our relatives by partnering with plants in the face of climate change and biocultural loss
Extended Abstract: A Modular and Open-Source Human-in-the-Loop Qualitative Analysis Framework for Multimodal Data
No full textQualitative research and data analysis (QDA) is a vital cornerstone of discourse analysis methods regularly applied to the genre of professional communication. This extended abstract highlights the need for and speculates on an open-source and modular human-in-the-loop (HITL) framework for multimodal QDA
Initial Exploration of Thematic Emergence in Students\u27 Reflections Post an Entrepreneurially Minded Learning Activity
No full textThis work is a preliminary exploration of thematic emergence in student reflections following a learning activity in Mechanics of Materials. Two independent groups of students enrolled in successive semesters were compared. One group of students experienced a traditional analytical learning activity, while the second group experienced an \u27entrepreneurially minded\u27 learning activity. Both groups submitted written reflections (\u27data\u27) after their respective learning activities. According to the Kern Engineering Entrepreneurial Network (KEEN), entrepreneurial-minded learning (EML) is a curious, connected, and value-creating way of problem-solving. Elements of Charmaz\u27s Grounded theory were applied to the data to extract contextual themes. First, the authors independently opencoded the data. Next, the codes were compared and discussed until a qualitative agreement was reached. Then, codes were collapsed into categories, from which notable thematic differences inductively emerged. Finally, Bloom\u27s taxonomy cognitive scores were applied to the categories and to the themes from the EML framework. The results show that student reflections on the EML-infused activity possess qualities aligned with higher-order Bloom\u27s levels. Future work will involve analyzing the rhetoric associated with EML in spoken discourse to deductively extract themes
Phenotypic and Genetic Associations Between Cardiovascular Disease Subtypes and Alzheimer\u27s Disease
No full textBACKGROUND: Cardiovascular disease (CVD) and Alzheimer\u27s disease (AD) are major public health concerns that share overlapping risk factors and potential mechanistic pathways. While vascular contributions to cognitive decline are well-documented, the specific relationships between AD and different CVD subtypes remain poorly understood. METHODS: We examined associations between AD and 11 CVD subtypes using logistic regression models in two large biobanks: the UK Biobank (n = 502,133) and the All of Us Research Program (n = 287,011). Models were adjusted for demographic, lifestyle, and clinical covariates. We also explored genetic overlap between AD and CVD traits through colocalization of significant single nucleotide polymorphisms (SNPs) (p \u3c 5×10) using genome-wide association study (GWAS) data. RESULTS: Most CVD subtypes were significantly associated with AD in both cohorts. Hypotension had the strongest and most consistent association, followed by hypertension and cerebral infarction. Acute myocardial infarction was the only subtype not significantly linked to AD. Genetic analyses revealed shared loci between AD and CVD-related traits, particularly in regions near APOE, MAPT, and genes influencing myocardial structure and vascular function. CONCLUSIONS: This study identifies subtype-specific CVD associations with AD across two diverse cohorts and highlights shared genetic architecture underlying heart-brain interactions. These findings underscore the importance of vascular health in AD risk and suggest that certain CVD subtypes, especially hypotension, may play underrecognized roles in cognitive decline
Preparation, high-temperature and low-temperature performance evaluation of bio-based polyurethane modified asphalt
Get PDFTo achieve sustainable and environmentally friendly development of pavement materials, it is essential to identify alternative materials to reduce dependence on petroleum resources. This study aims to functionalize castor oil (CO) with isocyanates to prepare bio-based polyurethane-modified asphalt (Bio-PUMA), determine its optimal preparation parameters, and evaluate the effects of Bio-PU content and isocyanate index (R) on the high- and low-temperature performance of Bio-PUMA. The orthogonal experimental design (OED), grey correlation grade analysis (GCGA), penetration, softening point, ductility, and viscosity were conducted to determine the preparation process and evaluate the performances of Bio-PUMA. The results show that the preparation factors affecting the performance of Bio-PUMA are ranked as follows: stirring temperature \u3e stirring time \u3e stirring rate. The optimal preparation parameters were the temperature of 155 °C, 30 min for T1 and 50 min for T2, 300 r/min for S1, and 600 r/min for S2. The temperature sensitivity of Bio-PUMA decreases gradually with the increase in Bio-PU content. As the R value increases, the temperature sensitivity decreases and then increases, with the lowest temperature sensitivity observed at R= 1.2. Increasing the Bio-PU content or the R value improves the high-temperature performance of Bio-PUMA but has a slightly negative impact on its low-temperature performance. It is recommended that the isocyanate index R in the Bio-PUMA formula should not exceed 1.5, and the content should not be less than 6 %
Enhancing grazing incidence sound absorption in three-dimensional printed triply periodic minimal surfaces through geometric asymmetry
No full textTriply periodic minimal surfaces (TPMS) offer promising absorption performance due to their tunable geometry. Previous findings under normal incidence conditions show that introducing geometric asymmetry can enhance sound absorption without increasing overall density. This study investigates whether those improvements hold under grazing incidence conditions with and without flow, which are more representative of practical flow environments. TPMS samples are fabricated using fused deposition modeling, and their acoustic response is measured in the Grazing Flow Impedance Tube (GFIT) at NASA Langley Research Center. Results confirm that symmetry-breaking improves low frequency absorption under grazing incidence, mirroring outcomes observed at normal incidence. These findings underscore the versatility of TPMS-based approaches for advanced noise mitigation while maintaining minimal mass. Overall, harnessing geometric asymmetry offers a powerful means to optimize performance across diverse incidence angles, laying the groundwork for lightweight, high-performance acoustic liners suitable for aerospace, automotive, and industrial applications
Textured 3D printed membrane-type metamaterials with controlled performance
No full textMembrane-type acoustic metamaterials are widely recognized for their lightweight and effective sound insulation properties. However, traditional manufacturing methods limit the ability to customize their geometries or seamlessly integrate them into other acoustic designs. In this study, we build upon our previous work on 3D printed membranes with variable thickness to introduce a novel approach for designing and manufacturing acoustic metamaterials with exceptional levels of customization. Our method enables the creation of flexible membranes with tailored porosity, tension, and textured surface patterns—features unattainable through conventional techniques. By manipulating these parameters through our custom G-code, we establish a streamlined workflow to control sound transmission loss without post-processing steps. We evaluate the acoustic performance using a four-microphone normal-incidence impedance tube setup and compare the measured transmission loss response with the acoustic mass law predictions for an equivalent limp membrane. This work underscores the transformative potential of 3D printing in advancing acoustic metamaterials, enabling tailored performance and seamless integration into diverse acoustic systems
Fall 2024 Computer Programming and Engineering Self-Efficacy Survey Data
No full textThis dataset was collected as part of a research study examining the impact of automated code critiquers on students’ programming and engineering self-efficacy in first-year engineering courses. The study involved pre- and post-surveys administered to students enrolled in ENG1101: Introduction to Engineering during Fall 2024 at Michigan Technological University. The research aims to understand how exposure to automated feedback tools, such as WebTA, influences confidence, persistence, and perceived competencies