Mechanical Engineering Commons^™

Review: Mechanics Of Mycelium Materials, Md Anwar Sadat Anik, Ehsanul Azim, Gerardo I. Zapata, Mohammad R. Islam

Mechanical Engineering Faculty Publications

The biological growth of fungal root structure, called mycelium, can be engineered to develop innovative fibrous and biocomposite materials. Mycelium materials have potential as sustainable alternatives to petroleum-derived materials for load-bearing applications. To realize this potential, there is an increasing effort dedicated to understanding the mechanics of mycelium materials. This work presents a systematic review of our current understanding of the mechanics of mycelium materials with a specific focus on structure–property relationships. The review first explores how the mycelium’s fiber network structure varies depending on whether it is grown as a two-dimensional (2D) membrane, a cellular foam, or as a …

Analysis Of The Fracture Toughness Of Ercual A2 Cladding On Api X70 Using The Instrumented Charpy Impact Test, Martín Aguirre-Pulido, Francisco Fernando Curiel-López, Jose Jaime Taha-Tijerina, Jorge Alejandro Verduzco-Martínez, Víctor Hugo López-Morelos, Heriberto Granados-Becerra, Ariosto Medina-Flores

Mechanical Engineering Faculty Publications

The degradation of steel used in the oil industry has become a serious problem due to the high costs associated with material loss from corrosion. Applying thin layers of corrosion-resistant material promises to be a viable alternative for extending the service life of pipelines. ERCuAl-A2 electrode claddings were applied to API X70 carbon steel using the MIG brazing process with direct current (DC) and pulsed current (P). The cladding was applied under three conditions: base material (BM) at room temperature, BM preheated to 120 °C, and Ni-buttered BM. Microhardness profiles and Charpy impact tests were performed on the MB and …

Effect Of Heat Treatments On The Corrosion Resistance Of A Trip Steel And Its Evaluation By Non-Destructive Testing, Karla Ivette Vega-Nava, Ariosto Medina-Flores, Marco Antonio Espinosa-Medina, José Sergio Pacheco-Cedeño, Héctor Guillermo Carreón-Garcidueñas, Francisco Fernando Curiel-López, Jose Jaime Taha-Tijerina

Mechanical Engineering Faculty Publications

The development of advanced high-strength steels (AHSS) for the automotive industry requires optimizing the balance between mechanical properties and durability in aggressive environments. This study investigates the effects of two heat treatment routes on the microstructure and corrosion resistance of a transformation-induced plasticity (TRIP) steel (Fe-0.2C-1.75Mn-0.5Si-1Al). Route A includes a full austenitizing step at 1000 °C prior to intercritical annealing, whereas Route B omits this step and begins directly with intercritical annealing at 800 °C. Microstructural characterization (SEM/XRD), electrochemical assays, and eddy current tests were employed. The results revealed that Route A yields a homogeneous microstructure with 12.7% retained austenite, …

Centrifugally Spun Silica Fibers For Lithium-Ion Battery Anodes: Structure And Cycling Stability, Alejandra Guerrero, Valeria Tirado, Jason Parsons, Mataz Alcoutlabi

Mechanical Engineering Faculty Publications

Introduction: Silicon dioxide (SiO2) fiber structures have attracted attention as alternative anode materials for lithium-ion batteries because of their ability to improve cycling stability compared to commercial silicon particles.

Materials and methods: SiO2 composite fibers were prepared by centrifugal spinning of polyvinylpyrrolidone (PVP)/SiO2 precursor solutions followed by calcination at 500–700 ◦C for different holding times to produce short-fiber composites and micro-belt SiO2 fiber structures. The morphology and crystal structure of the SiO2 short fibers and micro-belts were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), and X-ray Photoelectron Spectroscopy (XPS). Electrochemical performance was evaluated using CR2032 half-cells.

Results: The …

Enhanced Triboelectric Effect Using Functionalized Multiwalled Carbon Nanotube-Coated Fiber Mats For Biomechanical Energy Harvesting, Fernando Viesca, Diego De Leon, Kevin Alejandro, Rigobert Ybarra Jr., Md. Wasikur Rahman, Victoria Padilla, Horacio Vasquez, Karen Lozano, M. Jasim Uddin

Mechanical Engineering Faculty Publications

Triboelectric nanogenerators (TENGs) have emerged as a cutting-edge technology for developing self-powered wearable electronic devices. In this study, TENGs were fabricated using two fiber mats: forcespun polytetrafluoroethylene (FS-PTFE) microfibers and electrospun polyvinyl alcohol (ES-PVA) nanofiber (NF) mats. The FS-PTFE mats were coated with functionalized multiwalled carbon nanotubes (MWCNTs). Functionalized MWCNTs were dispersed in water-based solutions containing three different surfactants—sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, and Triton X-100 to enhance fiber interaction. The NF mats were subsequently immersed in aqueous systems. The surfactant facilitated the uniform deposition of COOH-MWCNTs onto the FS-PTFE fibers, serving as a negative layer, while ES-PVA mat …

Unveiling Value In Plastic Waste: Synthesis Of 1,3-Dioxolan-4-Ones From Polylactic Acid And Polyoxymethylene To Enhance Plastic Biodegradation, Mi-Hyun Lee, Joohyun Park, Hyeongyeong Lee, Woo Yeon Cho, Semin Son, Pyung Cheon Lee, In-Hwan Lee, Hye-Young Jang

Mechanical Engineering Faculty Publications

Catalytic plastic upcycling protocols are essential for resolving the environmental and economic challenges associated with massive plastic production and disposal, as they convert complex waste streams into value-added chemicals. We report an efficient acid-catalyzed upcycling strategy for transforming poly(lactic acid) (PLA) and polyoxymethylene (POM) plastic waste. This innovative process directly yielding dioxolanones (DOXs) can be extended to use POM with various naturally abundant α-hydroxy acids. This work significantly expands the high-value chemical portfolio derivable from common plastic wastes. Incorporation of the synthesized DOXs into the poly(L-lactic acid) (PLLA) backbone results in materials with enhanced thermal stability and superior biodegradability. Critically, …

Tribological Properties Of Aisi 420 Esr Stainless Steel Modified By Sequential Boriding And Nitriding, Melvyn Alvarez Vera, Rafael Carrera Espinoza, Valeria López López, Marc Wettlaufer, Stefan Barth, Juan Carlos Díaz Guillén, Héctor Manuel Hernández García, Rita Muñoz Arroyo, Javier A. Ortega, Marco A. Cruz-Gómez

Mechanical Engineering Faculty Publications

This study investigates the effects of surface thermochemical treatments using boriding, nitriding, and boronitriding on the microstructure and mechanical properties of martensitic stainless steel AISI 420 ESR. Powder-pack boriding, gas nitriding, and sequential boronitriding processes were applied to enhance surface hardness, wear resistance, and adhesion. The microstructural and mechanical properties of the surface samples were analyzed using scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, microhardness, and nanoindentation testing. Tribological behavior was analyzed using a pin-on-disk tribometer under dry-sliding wear conditions, with applied normal loads of 5 N and 10 N and a sliding distance of 1000 m. The results showed …

Patient‐Specific Computational Flow Simulation Reveals Adverse Hemodynamic Factors Associated With Occlusion Of Directional Branches After Fenestrated‐Branched Endovascular Aneurysm Repair, Kenneth Tran, Jesse Chait, Emmanuel Tenorio, Weiguang Yang, Alison Marsden, Bernardo Mendes, Jason T. Lee, Gustavo S. Oderich

Mechanical Engineering Faculty Publications

Background: Fenestrated and branched endovascular aneurysm repair can be complicated by branch vessel occlusion in the absence of structural stenosis. We hypothesized that computational flow simulation could identify adverse hemodynamic features associated with postfenestrated and branched endovascular aneurysm repair branch occlusion.

Methods: Patients undergoing 4-vessel fenestrated and branched endovascular aneurysm repair for Extent II to IV thoracoabdominal aortic aneurysms were retrospectively reviewed. Branches that occluded without identifiable kinking or stenosis on computed tomography were included, along with an equal cohort of anatomy-matched patent controls. Patient-specific pulsatile rigid-wall simulations were performed using SimVascular with individualized geometries and boundary conditions. Abnormal time-averaged …

Capturing Sclera Anisotropy Using Direct Collagen Fiber Models: Linking Microstructure To Macroscopic Mechanical Properties, Fengting Ji, Xuehuan He, Frederick Sebastian, Mohammad R. Islam, Hannah Schilpp, Bingrui Wang, Yi Hua, Rouzbeh Amini, Ian A. Sigal

Mechanical Engineering Faculty Publications

Collagen fibers are essential to the mechanical behavior of soft tissues, including sclera. Conventional models often represent these fibers statistically, potentially missing crucial aspects of their role in tissue behavior. In this study, we expand on a direct fiber modeling approach that we recently presented based on explicitly representing the sclera long, interwoven fiber bundles. Specifically, our goal was to capture specimen-specific 3D fiber architecture and anisotropic mechanics of four ovine sclera samples (superior from Eye-1, temporal and superior from Eye-2, and temporal from Eye-3), each tested under five conditions: equi-biaxial (1:1) and four non-equi-biaxial (1:0.75, 0.75:1, 1:0.5, and 0.5:1). …

Rheology-Guided Spinnability In Emulsion Forcespinning Of Water-In-Oil Nanofibers: Influence Of Surfactants And Internal Phase Concentration, Saptasree Bose, Alexandra Salinas, Evelyn Torres, Jose Ramirez, Elizabeth Gamez, Michelle A. Calabrese, Karen Lozano, Victoria Padilla

Mechanical Engineering Faculty Publications

This study explores the emulsion Forcespinning (FS) approach for fabricating nanofibers with a hydrophilic phase encapsulated within a hydrophobic polymer matrix. Key factors influencing fiber production and morphology, including the concentration of the internal water phase and the presence of ionic and nonionic surfactants, were systematically investigated. Additionally, the centrifugal spinnability of the emulsions was assessed using environmentally controlled dripping-onto-substrate (DoS) rheometry, correlating the observed extensional flow behavior and emulsion extensibility with fiber spinnability. The nanofibers were characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) spectroscopy. These findings offer critical …

Electromagnetic Formation Flying Using Alternating Magnetic Field Forces And Control Barrier Functions For State And Input Constraints, Sumit Suryakant Kamat, Thomas Michael Seigler, Jesse B. Hoagg

Mechanical Engineering Faculty Publications

This article presents a feedback control algorithm for electromagnetic formation flying with constraints on the satellites’ states and control inputs. The algorithm combines several key techniques. First, we use alternating magnetic field forces to decouple the electromagnetic forces between each pair of satellites in the formation. Each satellite’s electromagnetic actuation system is driven by a sum of amplitude-modulated sinusoids, where amplitudes are controlled in order to prescribe the time-averaged force between each pair of satellites. Next, the desired time-averaged force is computed from an optimal control that satisfies state constraints (i.e., no collisions and an upper limit on intersatellite speeds) …

Cross-Linking Peg Microgels With Mesoporous Organosilica Nanoparticles To Engineer Microporous Annealed Particle Scaffold Properties, Jonathan M. Zuidema, Alessandro Ajo, Marco Carofiglio, Luisa De Cola

Mechanical Engineering Faculty Publications

Microporous annealed particle (MAP) scaffolds composed of cross-linked microgels are emerging as important biomaterials due to their modular design, high porosity, and large surface area, which allow for highly tailored properties, cellular infiltration, nutrient and waste exchange, and improved drug release characteristics. To further expand on these technologies and enhance their modular design, thiolated mesoporous organosilica nanoparticles (ssMSN-SH), which degrade in response to glutathione, were first cross-linked inside of 4-arm poly(ethylene glycol) maleimide microgels. The microgel size, rheological properties, and payload release characteristics were determined. Hierarchical MAP scaffolds were then created by cross-linking 4-arm poly(ethylene glycol) maleimide microgels with ssMSN-SH. …

A Framework For Enhanced Circular Product Development With Total Life Cycle Considerations, Gisele Bortolaz Guedes, Fazleena Badurdeen, Ibrahim S. Jawahir

Mechanical Engineering Faculty Publications

Advancing circular product development (CPD) requires design decisions that account for the entire product life cycle, from material sourcing and manufacturing to use and end-of-use (EoU) stages, to ensure enhanced sustainability performance. Existing Product Development Process (PDP) models tend to emphasize isolated phases or perspectives with limited explicit consideration of the total product life cycle. This hinders the systematic embedding of various Circular Economy (CE) strategies during product development. Thus, designers and engineers lack a unified framework to determine when and where critical decisions should be made to effectively incorporate CE strategies such as effective resource selection, extending product use-life, …

A Unified Finite Element Framework For Cardiac Growth And Remodeling In Mitral Regurgitation Incorporating Fiber Reorientation And Baroreflex, Mohammad Mehri, Jonathan F. Wenk

Mechanical Engineering Faculty Publications

Mitral regurgitation (MR) triggers complex cardiac remodeling responses that alter the structure and function of the left ventricle (LV). While several models have been developed to predict myocardial growth in MR, they often neglect key concurrent adaptive mechanisms that influence both the pattern and severity of LV dilation. This study presents a unified finite element framework to systematically evaluate the individual and combined contributions of fiber reorientation (FR) and baroreflex regulation to LV growth and remodeling, along with the effects of myocardial material property changes associated with the acute and chronic phases of MR. A healthy baseline model and multiple …

Effects Of Metal-Modified Catalysts On The Desorption Performance Of Mixed Amine Solutions And Machine Learning Prediction, Xunxuan Heng, Zhenzhen Zhang, Longhua Zhu, Li Yang, Shugang Xie, Zeyu Wang, Dongtai Han, Fang Liu, Kunlei Liu

Mechanical Engineering Faculty Publications

The high energy penalty associated with solvent regeneration is still a major bottleneck in amine-based CO₂ capture. In this work, the effects of five solid acid catalysts on the desorption performance of a mixed-amine solvent were compared, and the HY catalyst with superior desorption behavior was selected and further modified with four transition metals (Co, Mn, Gr and Ce) to enhance its catalytic activity. The findings indicate that the CO₂ desorption capacity and maximum desorption rate of the Co-modified HY catalyst reach 48.96 mmol and 0.02211 mmol/s, corresponding to increases of 36.80% and 35.39% relative to the blank …

Effect Of Graphene Oxide On The Upconversion Photoluminescence Behavior Of Er/Yb Co-Doped Pvdf-Go Composite Nanofibers, Saptasree Bose, Jack Ryan Summers, Bhupendra B. Srivastava, Karen Lozano, Victoria Padilla-Gainza

Mechanical Engineering Faculty Publications

Upconversion photoluminescence (UCPL) materials, particularly rare-earth (RE) doped nanoparticles, have garnered significant attention due to their ability to convert near-infrared (NIR) excitation into visible emission, offering benefits such as high photostability, long lifetimes, low autofluorescence, and deep tissue penetration. Among various platforms, polymer-based one-dimensional (1D) nanofibers with in-situ lanthanide doping remain relatively unexplored, despite their superior mechanical flexibility, processability, and potential for improved luminescence performance. In this study, we report the fabrication and UCPL quenching behavior of Er3+/Yb3+ co-doped polyvinylidene difluoride (PVDF) nanofibers incorporated with graphene oxide (GO), synthesized for the first time using the scalable Forcespinning® technique. PVDF, a …

Three-Dimensional Printing Of Calcium Phosphate-Mesoporous Bioactive Glass Scaffolds For Bone Tissue Engineering, Ana Beatriz Gomes De Carvalho, Lais Medeiros Cardoso, Igor Paulino Mendes Soares, Joyce Rodrigues De Souza, Arpita Roy, Prabaha Sikder, Et. Al.

Mechanical Engineering Faculty Publications

Calcium phosphate cements (CPCs) and biomaterials, such as mesoporous bioactive glass (MBG), are critical for bone tissue engineering. This study aimed to 3D-print CPC scaffolds modified with MBG to enhance their osteogenic potential and regenerative ability. MBG powder was synthesized and characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), and nitrogen adsorption-desorption techniques. A commercial CPC ink (hydroxyapatite/alpha-tricalcium phosphate) was mixed with 5% MBG (w/w; CPC/MBG), and, after rheological assessment, the mixture was used to obtain scaffolds via 3D printing. These scaffolds were then tested for chemical, morphological, and mechanical properties, as well as ion release analysis. Unmodified CPC …

Development And Validation Of 2nn-Meam Interatomic Potential For Sc And Al-Sc Alloys Thermodynamics Solidification And Intermetallic Ordering, Avik Mahata

Mechanical Engineering Faculty Publications

We present a second-nearest-neighbor Modified Embedded Atom Method (2NN–MEAM) potential for Scandium (Sc) and Aluminum-Scandium (Al–Sc) alloys that unifies cohesive, thermodynamic, and solidification behavior within a single transferable framework. The Sc component accurately reproduces cohesive energy, lattice constants, defect energetics, and the experimental melting point obtained from two-phase coexistence, demonstrating reliable description of both hcp and liquid phases. The Al–Sc binary interaction parameters were fitted using the L1₂–Al₃Sc reference and benchmarked against first-principles and calorimetric data. The potential reproduces the strong negative formation enthalpy of Al₃Sc (–0.45 eV atom⁻¹), correct relative stability …

A Review Of Waste Heat Sources For District Heating, Olamide Opadokun, Yong Tao, Julian Lamb

Mechanical Engineering Faculty Publications

As the world's energy needs rise, carbon emissions and climate change become a bigger concern. Therefore, there is a growing need for cleaner energy sources as well as higher levels of energy efficiency. Building energy is of great interest to researchers and policymakers, as it accounts for about a third of global energy consumption, and this is projected to rise as more people gain access to higher incomes and improved amenities. For over a century, district energy systems have proved to be an efficient means of providing thermal energy to buildings, and developments in district heating have enabled the use …

Wearable Triboelectric Nanogenerators Based Sensors For Human Cardiovascular Monitoring: Progress And Perspectives, Mashrufa Akther, Andrea K. Quezada, Md. Arafat Hossain, Julia I. Salas, Md. Mahmud Alam, Mohammed Jasim Uddin

Mechanical Engineering Faculty Publications

Cardiovascular conditions remain the leading cause of death worldwide, driving a critical need for non-invasive, continuous, and dependable health monitoring results. Triboelectric nanogenerators have emerged as a groundbreaking technology enabling self-powered wearable sensors that convert natural biomechanical energy, such as heartbeat, pulse wave, and body motion, into electrical signals. The paper reviews the recent progress and development in TENG-based wearable sensors for cardiovascular monitoring, with a focus on monitoring particular and clinical healthcare. The working principles, advanced materials, structural designs, and integration with wireless data transmission, machine literacy, and bio-signal processing technologies are explored in this article. Operations, including heart …

A Magnesium Alloy With High Corrosion Resistance, Hardness And Elastic Modulus Enabled By Elemental Synergy, Alexander Helmer, Manoj V. Mugale, Tushar Borkar, Rajeev K. Gupta

Mechanical Engineering Faculty Publications

A magnesium alloy containing Ca, Ti, Zn, and In was synthesized via high-energy ball milling of elemental powders followed by spark plasma sintering. X-ray diffraction and scanning electron microscopy revealed a homogeneous matrix with dispersed Mg-rich phases and intermetallics. Potentiodynamic polarization tests revealed low corrosion current density (9.6 f 2.1 mu A/cm2), a noble corrosion potential (-1197 f 4 mVSCE), and a clear passive region, indicating excellent corrosion resistance. Nanoindentation tests showed high hardness (2.61 f 0.21 GPa) and elastic modulus (55.35 f 5.47 GPa), exceeding those of commercial Mg alloys.

The Role Of Atmospheric Turbulence On Cloud Droplet Distribution And Droplet Impaction On An Airfoil, Arash Shad, Hashnayne Ahmed, ‪Nadim Zgheib, S. Balachandar, S. A. Sherif

Mechanical Engineering Faculty Publications

We conduct turbulence-informed Euler–Lagrange simulations of droplet-laden flow to examine the effects of atmospheric turbulence on droplet impingement characteristics on a NACA 0012 airfoil. We implement statistical overloading, whereby we inject millions of droplets, ranging in diameter from 1 to 160 microns, upstream of the airfoil at an average streamwise velocity of 120 m/s. Within a fraction of a second, these droplets would have either impinged on the airfoil or continued downstream. While the incoming air flow is maintained uniform, droplet injection is informed by ambient turbulence, affecting both the droplet velocity distribution as well as the size-dependent preferential concentration …

Microstructural Evolution And Magnetic Properties Of Spark Plasma Sintered Smco5 And Smco5-Fe Composites, Farhan Ishrak, Michael Lastovich, Fu-Yun Tsai, Charles Perkins Iv, Henri Baldino, Alex Helmer, Sean Rego, Sanoj Karki, Daniel Hedlund, Rajeev Gupta, Tushar Borkar

Mechanical Engineering Faculty Publications

Optimizing SmCo(5-)based nanocomposites for high-temperature magnetic applications requires balancing coercivity and saturation magnetization, properties often compromised by grain coarsening, oxidation, and secondary phase formation during conventional sintering. This study investigates the microstructural evolution and magnetic properties of SmCo5 and SmCo5-Fe composites processed via high-energy ball milling followed by spark plasma sintering at 900 degrees C and 1000 degrees C, a route designed to retain the nanostructure while enabling rapid densification compared to conventional sintering. A suite of characterization techniques, including electron microscopy, X-ray diffraction, magnetometry, Magneto-optical Kerr effect, and magnetic force microscopy, reveals the extent of consolidation, phase composition, and …

Advanced Microstructured Batio3-Embedded Pvdf–Hfp/Peo Film For Enhanced Triboelectric Interface In Self-Sufficient Energy Generation And Sensing, Rigobert Ybarra, Diego De Leon, Michael Moreno, Cesar Sanchez, Fernando Viesca, Kevin Alejandro, Shishir Timilsena, Nicholas Dimakis, Joseph H. Dumont, Tommy Rockward, Tarik J. Dickens, Md. Wasikur Rahman, Mohammed Jasim Uddin

Mechanical Engineering Faculty Publications

The global reliance on fossil fuels and natural gas has largely dominated the energy production field, but due to finite resource depletion and escalating greenhouse gas emissions, the immediate exploration of sustainable energy alternatives to mitigate climate change and ensure resource security has been a major concern. There has been extensive research into other more renewable methods of energy production, such as wind and hydropower. Of these current energy generation types, there are many areas of untapped potential from the mechanical movements generated ambiently not only in the large scale of power generation but also on a smaller scale. The …

Tissue-Like Fracture Toughness And Stress–Relaxation Ability In Pva-Agar-Based Hydrogels For Biomedical Applications, Ismael Lamas Jr., Bhuvana L. Chandrashekar, Cláudia C. Biguetti, Mohammad R. Islam

Mechanical Engineering Faculty Publications

Soft tissues exhibit remarkable stretchability, fracture toughness, and stress–relaxation ability. They possess a large water content to support cellular processes. Mimicking such a combination of mechanical and physical properties in hydrogels is important for tissue engineering applications but remains challenging. This work aims to develop a hydrogel that can combine excellent mechanical properties with cellular viability. The research focused on polyvinyl alcohol (PVA)/agar double-network (DN) hydrogels, fabricated by thermal gelation and freeze–thawing methods. Their mechanical properties were characterized through tension, compression, fracture, and stress–relaxation tests, and their cellular viability was measured through cytotoxicity tests. The results show that the PVA/agar …

Effect Of Graphene Nanoplatelets Fraction On The Microstructure And Mechanical Properties Of Inconel 718 Composites Prepared By Spark Plasma Sintering, Sanoj Karki, Manoj Mugale, Satyavan Digole, Amit Choudhari, Mayank Garg, Caleb Schenck, Fu-Yun Tsai, Bharat Gwalani, Tushar Borkar

Mechanical Engineering Faculty Publications

Nickel-based superalloy, particularly Inconel 718, is a promising candidate in advanced structural and high-temperature applications, including turbine blades, combustors, and turbochargers. However, high-efficiency energy systems such as jet engines and land-based gas turbines demand increasingly high strength for advanced structural applications. Therefore, significant efforts are underway to enhance the strength of these materials. Reinforcement of graphene nanoplatelet (GNP), owing to its exceptional mechanical strength, lightweight, high aspect ratio, and high level of coherency with metal matrix, has been proposed as an effective way of incorporating high strength into the existing Inconel 718. In addition, the spark plasma-assisted heating process is …

A Biocompatible Nitinol Based Triboelectric Stent Sensor For Prospective Cardiovascular Health Monitoring, Ulises Vidaurri Romero, Sk Shamim Hasan Abir, Najlah Karam, Mariana Torres, Shahria Ahmed, Md. Wasikur Rahman, Bahareh Azimi, Serena Danti, Jianzhi Li, M. Jasim Uddin

Mechanical Engineering Faculty Publications

Triboelectric nanogenerators (TENGs) have been considered as an effective approach for self-powered systems. Currently, coronary heart disease remains the leading cause of death in the United States. This can be easily resolved by balloon angioplasty or a specialized mesh tube called a stent. This study demonstrates a stent sensor made of nitinol, a nickel—titanium alloy used in the medical field for its pseudo-elasticity and strong corrosion resistance, poly(vinylidene fluoride) (PVDF) and polydimethylsiloxane (PDMS), which can measure several physiological parameters while placing it in the arteries. This nitinol health monitor sensor (NHMS) device thus integrates the TENG with a specific medical …

Probing The Effect Of Peg-Dna Interactions And Buffer Viscosity On Tethered Dna In Shear Flow, Fatema Tuz Zohra, Huda Al-Zuhairi, Jefferson Reinoza, Hyeongjun Kim, Andreas Hanke

Mechanical Engineering Faculty Publications

DNA flow-stretching is a widely employed, powerful technique for investigating the mechanisms of DNA-binding proteins involved in compacting and organizing chromosomal DNA. We combine single-molecule DNA flow-stretching experiments with Brownian dynamics simulations to study the effect of the crowding agent polyethylene glycol (PEG) in these experiments. PEG interacts with DNA by an excluded volume effect, resulting in compaction of single, free DNA molecules in PEG solutions. In addition, PEG increases the viscosity of the buffer solution. By stretching surface-tethered bacteriophage lambda DNA in a flow cell and tracking the positions of a quantum dot labeled at the free DNA end …

Microstructural Investigation Of Graphene Reinforced Nickel Aluminum Bronze Prepared Via Laser Powder Bed Fusion, Wen Qian, Maxwyll Mcconnell, Jazmin Ley, Luke Schwaninger, Xin Chen, Bai Cui, Joseph A. Turner

Mechanical Engineering Faculty Publications

Nickel aluminum bronze (NAB) powders coated with reduced graphene oxide (RGO) were successfully fabricated using additive manufacturing (AM) via laser powder bed fusion. The resulting samples were characterized using a suite of complementary techniques, including x-ray diffraction, scanning electron microscopy, energy-dispersive x-ray spectroscopy, nanoindentation, x-ray computed tomography, and electron backscatter diffraction. These methods were employed to reveal the micro- and nanoscale features within the fine dendritic microstructure. The as-fabricated microstructures were observed to deviate significantly from typical as-cast configurations. In the AM RGO-coated NAB specimens, the formation of the κ_I phase was notably suppressed and is attributed to the …

Recent Advances In Modelling Of Frost Formation For Mechanical Systems, Yong Tao

Mechanical Engineering Faculty Publications

The physics underlying frost and ice formation has been extensively studied over the past few decades, with significant contributions to our understanding of this phenomenon. These insights have primarily been applied to engineering systems with refrigerated surfaces, such as refrigerators, freezers and heat pumps of various sizes. Despite considerable progress, the dynamic and complex mechanisms governing frost and ice formation remain an active area of research, as competing factors continue to challenge predictive accuracy. The increasing interest from stakeholders in reducing energy consumption and carbon footprints in mechanical systems further underscores the importance of advancing modelling and simulation capabilities in …