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Mechanical Engineering Faculty Publications

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Articles 151 - 180 of 618

Full-Text Articles in Mechanical Engineering

Ai-Enabled Droplet Detection And Tracking For Agricultural Spraying Systems, Praneel Acharya, Travis A. Burgers, Doang Nguyen Nov 2022

Ai-Enabled Droplet Detection And Tracking For Agricultural Spraying Systems, Praneel Acharya, Travis A. Burgers, Doang Nguyen

Mechanical Engineering Faculty Publications

his work leverages recent advancements in com- puter vision and deep learning to detect and track the motion of droplets captured by a camera. While classical computer vision techniques have been employed for detection and tracking, those approaches have limitations and are not trivially extended to droplets. We approach the problems of droplet detection and tracking through a data-driven framework, in which an annotated database of droplet images is built and object detection and tracking models are trained on this database. The accuracy of the model is evaluated and the whole process is discussed. At this point, droplet geometric properties …


3d-Printed Piezoelectric Porous Bioactive Scaffolds And Clinical Ultrasonic Stimulation Can Help In Enhanced Bone Regeneration, Prabaha Sikder, Phaniteja Nagaraju, Harsha P.S. Naganaboyina Nov 2022

3d-Printed Piezoelectric Porous Bioactive Scaffolds And Clinical Ultrasonic Stimulation Can Help In Enhanced Bone Regeneration, Prabaha Sikder, Phaniteja Nagaraju, Harsha P.S. Naganaboyina

Mechanical Engineering Faculty Publications

This paper presents a comprehensive effort to develop and analyze first-of-its-kind design-specific and bioactive piezoelectric scaffolds for treating orthopedic defects. The study has three major highlights. First, this is one of the first studies that utilize extrusion-based 3D printing to develop design-specific macroporous piezoelectric scaffolds for treating bone defects. The scaffolds with controlled pore size and architecture were synthesized based on unique composite formulations containing polycaprolactone (PCL) and micron-sized barium titanate (BaTiO3) particles. Second, the bioactive PCL-BaTiO3 piezoelectric composite formulations were explicitly developed in the form of uniform diameter filaments, which served as feedstock material for the fused filament fabrication …


Sensitivity Analysis Of Frost Deposition In Turbulent Flow Over A Cold Plate Using Direct Numerical Simulation, N. Farzaneh, ‪Nadim Zgheib, S. A. Sherif, S. Balachandar Nov 2022

Sensitivity Analysis Of Frost Deposition In Turbulent Flow Over A Cold Plate Using Direct Numerical Simulation, N. Farzaneh, ‪Nadim Zgheib, S. A. Sherif, S. Balachandar

Mechanical Engineering Faculty Publications

We use a recently-developed, turbulence-informed physics-based model to study frost buildup over a flat plate subjected to turbulent flow. The plate temperature is held fixed but varied across simulations in the range −10◦C ≤ T∗ p ≤ −5◦C. Similarly, the free-stream temperature and humidity ratio are also held fixed but varied across simulations in the range 0◦C ≤ T∗∞ ≤ 20◦C and 3.77 × 10−3 ≤ ew∞ ≤ 1.47×10−2, respectively. We find the Nusselt and Sherwood numbers, when scaled by the frost surface to free stream temperature and humidity ratio difference, respectively, to become independent of free-stream temperature and humidity …


Synthesis Of Color Tunable Piezoelectric Nanogenerators Using Cspbx3 Perovskite Nanocrystals Embedded In Poly(D,L-Lactide) Membranes, Sk Shamim Hasan Abir, Julio E. Trevino, Bhupendra B. Srivastava, Muhtasim Ul Karim Sadaf, Julia I. Salas, Karen Lozano, Mohammed Jasim Uddin Nov 2022

Synthesis Of Color Tunable Piezoelectric Nanogenerators Using Cspbx3 Perovskite Nanocrystals Embedded In Poly(D,L-Lactide) Membranes, Sk Shamim Hasan Abir, Julio E. Trevino, Bhupendra B. Srivastava, Muhtasim Ul Karim Sadaf, Julia I. Salas, Karen Lozano, Mohammed Jasim Uddin

Mechanical Engineering Faculty Publications

In recent years, inorganic perovskite materials have emerged as a great potential in optoelectronic and flexible nanogenerator applications. In this study, we have synthesized blue to green tunable photoluminescent (PL) inorganic CsPbX3 (X-Cl/Br) perovskite nanocrystals (NCs) utilizing a heat treatment process at a temperature of 150°C. The purity of the NC’s luminescence was analyzed utilizing PL spectroscopy and the pristine blue and green emissions were observed at a 365 nm wavelength under ultraviolet light. Furthermore, the NCs were embedded in a poly(D,L-lactide) (PDLLA) polymer matrix to fabricate flexible blue and green luminous CsPbX3-PDLLA piezoelectric nanogenerators (CPX-PDLLA PENGs). The Fourier-transform infrared …


Tensegrity Laboratory Drilling Rig For Earth And Space Drilling, Mining, And Exploration, Mohamed S. Khaled, Muhao Chen, Enrique Z. Losoya, Luis A. Rodriguez, Eduardo Gildin, Robert E. Skelton Oct 2022

Tensegrity Laboratory Drilling Rig For Earth And Space Drilling, Mining, And Exploration, Mohamed S. Khaled, Muhao Chen, Enrique Z. Losoya, Luis A. Rodriguez, Eduardo Gildin, Robert E. Skelton

Mechanical Engineering Faculty Publications

Drilling operations are increasingly becoming a manufacturing process where repeatability, versatility, and speed matter the most for an operator or future space missions. Nonetheless, the ongoing energy transition efforts will undoubtedly shape the objectives and priorities of drilling operators into new markets with unexplored technical challenges. Versatility, mobility, and automated systems will play crucial roles in determining successful applications. This study explores and introduces the application of tensegrity-based structures, commonly used in space exploration, to Earth and Space drilling systems by modeling, designing, and building a tensegrity-based miniature drilling rig. Robust models for designing a drilling rig based on tensegrity …


Pseudo-Stem Banana Fiber As A Potential Low-Cost Adsorbent To Remove Methylene Blue From Synthetic Wastewater, Md. Wasikur Rahman, Sumaya Tarannum Nipa, Sarmin Zaman Rima, Md. Mahmudul Hasan, Raghunath Saha, Md. Abdul Halim, Yousuf Ali, Anjan Deb Sep 2022

Pseudo-Stem Banana Fiber As A Potential Low-Cost Adsorbent To Remove Methylene Blue From Synthetic Wastewater, Md. Wasikur Rahman, Sumaya Tarannum Nipa, Sarmin Zaman Rima, Md. Mahmudul Hasan, Raghunath Saha, Md. Abdul Halim, Yousuf Ali, Anjan Deb

Mechanical Engineering Faculty Publications

In this work, pseudo-stem banana (Musa acuminata) (PBF) fiber was utilized as a potential low-cost natural adsorbent to uptake methylene blue (MB) dye from synthetic wastewater by batch adsorption process. Different adsorption factors like contact time, pH, initial concentration, and adsorbent dosage were explored and found that the separation process is strongly pH dependent. Additionally, the adsorption data were fitted with various adsorption isotherms like Langmuir, Freundlich, Temkin, and Dubinin–Radhushkevich models to detect the adsorption equilibrium phenomena. Reaction kinetics was inspected using pseudo-first-order and second-order kinetic models. Mass transfer and intra-particle diffusion analyses indicate the adsorption mechanism of the system …


Tuning The Thermodynamic, Optical, And Rheological Properties Of Thermoresponsive Polymer Solutions Via Silica Nanoparticle Shape And Concentration, Christopher A P Neal, Valeria León, Michelle C. Quan, Nondumiso O. Chibambo, Michelle A. Calabrese Sep 2022

Tuning The Thermodynamic, Optical, And Rheological Properties Of Thermoresponsive Polymer Solutions Via Silica Nanoparticle Shape And Concentration, Christopher A P Neal, Valeria León, Michelle C. Quan, Nondumiso O. Chibambo, Michelle A. Calabrese

Mechanical Engineering Faculty Publications

Hypothesis

The shape and quantity of hydrophilic silica nanoparticles (NPs) can be used to tune the microstructure, rheology, and stability of phase-separating polymer solutions. In thermoresponsive polymer systems, silica nanospheres are well-studied whereas anisotropic NPs have little literature precedent. Here, we hypothesize that NP shape and concentration lower the onset of rheological and turbidimetric separation of aqueous poly(N-isopropyl acrylamide) (PNIPAM) solutions.

Experiments

Differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR), turbidimetry, and oscillatory rheology are utilized to examine interactions between NPs, PNIPAM, and water and to track changes in phase separation and mechanical properties due to NP concentration and shape. …


Navigating The Virtual Landscape: Implementing A Pedagogical Framework In A Virtual Summer Engineering Course To Enhance Students' Academic Development, Eleazar Marquez, Samuel Garcia Aug 2022

Navigating The Virtual Landscape: Implementing A Pedagogical Framework In A Virtual Summer Engineering Course To Enhance Students' Academic Development, Eleazar Marquez, Samuel Garcia

Mechanical Engineering Faculty Publications

In this evidence-based practice paper, the recently established CIRE educational model was incorporated, and modified, to establish an alternative pedagogical framework for a virtual, fast-paced summer engineering course in a private university in Texas. Transitioning to fully online courses in the wake of COVID-19 required a rapid modification of traditional pedagogical methods to overcome challenges such as the lack of academic resources and established campus practices, while simultaneously ensuring the academic and social development of students. In this regard, a pedagogical framework known as the CIRE model – which is the acronym for Communication, Initiation, Reduction, and Extension – was …


In-Person Instruction Or Remote Learning?: Understanding Students' Learning Experiences During Covid-19, Eleazar Marquez, Samuel Garcia Aug 2022

In-Person Instruction Or Remote Learning?: Understanding Students' Learning Experiences During Covid-19, Eleazar Marquez, Samuel Garcia

Mechanical Engineering Faculty Publications

Research attests that student success in engineering education is cultivated largely due to classroom environments, academic inclusion, and engagement in undergraduate research. It is further revealed that the social and academic fabric of the institution such as academic advising, peer tutoring, disability services, and outdoor recreational programs is essential towards fostering well-being, recruitment, retention, and student success. However, these studies were conducted in a period in which students experienced traditional face-to-face instruction. In the wake of COVID-19, most institutions responded by terminating in-person instruction, mandating to seek off-campus housing, and shifting to a fully remote context. As such, educators were …


Biodiesel Production From A Non-Edible Source Of Royna (Aphanamixis Polystachya) Oil, Md. Wasikur Rahman, Asim Kumar Mondal, Md Shakil Hasan Aug 2022

Biodiesel Production From A Non-Edible Source Of Royna (Aphanamixis Polystachya) Oil, Md. Wasikur Rahman, Asim Kumar Mondal, Md Shakil Hasan

Mechanical Engineering Faculty Publications

Background

Rapid consumption of fossil fuels as well as rising environmental deterioration caused by extreme CO2 emissions has become crucial in searching for a clean and renewable energy source such as biodiesel. The current work is an attempt to produce biodiesel from a potential non-edible feedstock of Aphanamixis polystachya, locally known as ‘Royna’ seed oil in Bangladesh.

Methods

Royna oil was extracted from the seed by Soxhlet extraction method. Biodiesel was synthesized by a three-step process: saponification of oil, followed by acidification of the soap, and esterification of the free fatty acid (FFA).

Results

The result presented showed that …


Development Of A Bootcamp For Freshman Student Success During Covid-19 Transition, Eleazar Marquez, Noe Vargas Hernandez, Arturo A. Fuentes Aug 2022

Development Of A Bootcamp For Freshman Student Success During Covid-19 Transition, Eleazar Marquez, Noe Vargas Hernandez, Arturo A. Fuentes

Mechanical Engineering Faculty Publications

Results from assessment show that passing rates in introductory courses as well as retention rates of first-year students in the College of Engineering and Computer Science at a HSI significantly dropped with the advent of COVID-19. Such results and trends provide an overall perspective on the academic preparation of incoming students. There is a high concern that the necessary skill set (e.g., adaptability, persistence, and performance) of the new cohort of students, who are primarily underrepresented Hispanics from underserved and challenged communities from the Rio Grande Valley, is not optimal for the rigor of engineering education. To this end, an …


Lubrication Performance Of Sunflower Oil Reinforced With Halloysite Clay Nanotubes (Hnt) As Lubricant Additives, Md Abu Sayeed Biswas, Md Mashfiqur Rahman, Javier A. Ortega, Laura Peña-Parás, Demófilo Maldonado-Cortés, José A. González, Ricardo Cantú, Adrián Campos, Eugenio Flores Jul 2022

Lubrication Performance Of Sunflower Oil Reinforced With Halloysite Clay Nanotubes (Hnt) As Lubricant Additives, Md Abu Sayeed Biswas, Md Mashfiqur Rahman, Javier A. Ortega, Laura Peña-Parás, Demófilo Maldonado-Cortés, José A. González, Ricardo Cantú, Adrián Campos, Eugenio Flores

Mechanical Engineering Faculty Publications

This study evaluates the tribological performance of nanolubricants of a vegetable oil (sunflower oil) reinforced with different concentrations of environmentally-friendly nanoparticles of halloysite clay nanotubes (HNTs). Tribological characterization was performed under different conditions to determine its effect on the nanolubricants’ performance and optimal HNT concentration. The tribological performances under low and high contact pressures were analyzed with a block-on-ring tribometer following the ASTM G-077-05 standard procedure. The extreme pressure (EP) properties of the nanolubricants were determined with a T-02 four-ball tribotester according to the ITeE-PIB Polish method for testing lubricants under scuffing conditions. In addition, the lubrication performance of the …


Transient Thermal Analysis Of A Railroad Bearing Adapter For Optimal Placement Of Onboard Sensors, Javier E. Arroyo, Constantine Tarawneh, Arturo Fuentes, Roberto A. Garcia, Jose G. Gallegos Jun 2022

Transient Thermal Analysis Of A Railroad Bearing Adapter For Optimal Placement Of Onboard Sensors, Javier E. Arroyo, Constantine Tarawneh, Arturo Fuentes, Roberto A. Garcia, Jose G. Gallegos

Mechanical Engineering Faculty Publications

Bearing temperature serves as an important metric used in identifying defective bearings in the rail industry. Current defect detection systems, such as the Hot Box Detectors (HBDs), are used to measure the temperature of freight car roller bearings. The HBD is a wayside device that utilizes a non-contact infrared sensor to determine the operating temperature of a railroad bearing as it passes over the HBD. Railroads analyze the data collected by HBDs to detect and flag defective bearings. If the operating temperature of a bearing surpasses a predetermined threshold, an emergency stop is initiated, and the bearing is removed from …


Improved Guidelines Of Indoor Airborne Transmission Taking Into Account Departure From The Well-Mixed Assumption, Jorge S. Salinas, K. A. Krishnaprasad, ‪Nadim Zgheib, S. Balachandar Jun 2022

Improved Guidelines Of Indoor Airborne Transmission Taking Into Account Departure From The Well-Mixed Assumption, Jorge S. Salinas, K. A. Krishnaprasad, ‪Nadim Zgheib, S. Balachandar

Mechanical Engineering Faculty Publications

The well-mixed assumption has been widely used in predicting the spread of infectious diseases in indoor spaces. It is to be expected that a perfect well-mixed state will not be achieved in an indoor space at any reasonable level of ventilation. This work evaluates the well-mixed assumption by comparing the theory with results from large eddy simulations. The robustness of the well-mixed theory is established by comparing at four different levels. The comparison also points out systematic departures in pathogen concentration which can be accurately accounted for with an easily implementable correction factor to quantities such as cumulative exposure time. …


Performance Of A Thermoelectric-Based Energy Harvesting Device On A Realistic Railroad Route, Martin Amaro Jr., Constantine Tarawneh, Heinrich D. Foltz, Ruben Aguilera Toro, Curtis Pena Jun 2022

Performance Of A Thermoelectric-Based Energy Harvesting Device On A Realistic Railroad Route, Martin Amaro Jr., Constantine Tarawneh, Heinrich D. Foltz, Ruben Aguilera Toro, Curtis Pena

Mechanical Engineering Faculty Publications

Researchers at the University Transportation Center for Railway Safety (UTCRS) have developed an onboard wireless monitoring device to gauge the health of freight railcar rolling stock. A wireless system will allow for preemptive maintenance to occur, potentially saving millions of dollars in damages and ensuring the safety of passengers and cargo. A prototype energy harvester has been developed that can extend the battery life of the wireless monitoring device. It uses Thermoelectric Generators (TEGs) mounted on the bearing adapter to convert heat generated from the bearings to electricity. Previous results have shown that, under optimal conditions, TEGs have been able …


Conductive Polymer Pad For Use In Freight Railcar Bearing Adapters, Jesse Aguilera, Constantine Tarawneh, Harry Siegel, Robert Jones, Santana Gutierrez Jun 2022

Conductive Polymer Pad For Use In Freight Railcar Bearing Adapters, Jesse Aguilera, Constantine Tarawneh, Harry Siegel, Robert Jones, Santana Gutierrez

Mechanical Engineering Faculty Publications

Many freight railcars rest on polymer adapter pads made of injection-molded Thermoplastic Polyurethane (TPU) polymers which feature two copper studs to provide electrical conductivity through the pad. This design feature allows signal transmission from the track to the onboard systems, including cargo gates and pneumatic actuators. While in service, the polymer pads experience impact and cyclic loading that produce shear, resulting in the abrasive wear and plastic compression of the copper studs which leads to signal interruptions and loss of function requiring the periodic replacement of these polymer pads. This causes increased downtime due to maintenance and reduced reliability in …


Pilot Field Test Of An Onboard Wireless Condition Monitoring System For Railroad Rolling Stock, Marco A. Barrera, Heinrich D. Foltz, Lee R. Cantu, Brent Wilson, Constantine Tarawneh, Byron Porter Jun 2022

Pilot Field Test Of An Onboard Wireless Condition Monitoring System For Railroad Rolling Stock, Marco A. Barrera, Heinrich D. Foltz, Lee R. Cantu, Brent Wilson, Constantine Tarawneh, Byron Porter

Mechanical Engineering Faculty Publications

The “internet of things” has revolutionized the methods in which many industries have optimized performance and component defect detection by providing real-time feedback through the implementation of data processing and wireless communication. Despite these advancements, the railway industry has lingered stagnant in its approach of adopting these advanced prognostic detection systems, and instead relies on discretely (25–40 miles) placed trackside condition monitoring systems, aka wayside. These wayside systems are primarily used to detect abnormal operating conditions in railcar rolling stock components. However, while they have been used for decades to address imminent threats to derailments and/or safety, they have unfortunately …


Estimation Of Joint Moments During Turning Maneuvers In Alpine Skiing Using A Three Dimensional Musculoskeletal Skier Model And A Forward Dynamics Optimization Framework, Dieter Heinrich, Antonie J. Van Den Bogert, Werner Nachbauer Jun 2022

Estimation Of Joint Moments During Turning Maneuvers In Alpine Skiing Using A Three Dimensional Musculoskeletal Skier Model And A Forward Dynamics Optimization Framework, Dieter Heinrich, Antonie J. Van Den Bogert, Werner Nachbauer

Mechanical Engineering Faculty Publications

In alpine skiing, estimation of the joint moments acting onto the skier is essential to quantify the loading of the skier during turning maneuvers. In the present study, a novel forward dynamics optimization framework is presented to estimate the joint moments acting onto the skier incorporating a three dimensional musculoskeletal model (53 kinematic degrees of freedom, 94 muscles). Kinematic data of a professional skier performing a turning maneuver were captured and used as input data to the optimization framework. In the optimization framework, the musculoskeletal model of the skier was applied to track the experimental data of a skier and …


Simple, Accurate Calculation Of Mechanical Power In Pressure Controlled Ventilation (Pcv), Christine A. Trinkle, Richard N. Broaddus, Jamie L. Sturgill, Christopher M. Waters, Peter E. Morris May 2022

Simple, Accurate Calculation Of Mechanical Power In Pressure Controlled Ventilation (Pcv), Christine A. Trinkle, Richard N. Broaddus, Jamie L. Sturgill, Christopher M. Waters, Peter E. Morris

Mechanical Engineering Faculty Publications

Background: Mechanical power is a promising new metric to assess energy transfer from a mechanical ventilator to a patient, which combines the contributions of multiple parameters into a single comprehensive value. However, at present, most ventilators are not capable of calculating mechanical power automatically, so there is a need for a simple equation that can be used to estimate this parameter at the bedside. For volume-controlled ventilation (VCV), excellent equations exist for calculating power from basic ventilator parameters, but for pressure-controlled ventilation (PCV), an accurate, easy-to-use equation has been elusive.

Results: Here, we present a new power equation …


Quantum Dynamics Effects On Amplitude-Frequency Response Of Superharmonic Resonance Of Second-Order Of Electrostatically Actuated Nems Circular Plates, Dumitru Caruntu, Julio S. Beatriz May 2022

Quantum Dynamics Effects On Amplitude-Frequency Response Of Superharmonic Resonance Of Second-Order Of Electrostatically Actuated Nems Circular Plates, Dumitru Caruntu, Julio S. Beatriz

Mechanical Engineering Faculty Publications

This work deals with the effects of Casimir and/or van der Waals forces (quantum dynamics phenomena) on the amplitude-frequency response of the superharmonic resonance of second-order of axisymmetric vibrations of electrostatically actuated nanoelectromechanical systems (NEMS) clamped circular plates. Electrostatic actuation consists of alternating current (AC) voltage of magnitude to produce hardexcitationsandoffrequencynearonefourththenaturalfrequencyoftheclamped circular plate. The intermolecular forces Casimir and van der Waals, damping force, and electrostatic force are the forces acting on the NEMS plate. Six Reduced Order Models (ROMs) with one and up to 6 modes of vibration are used. The ROM with one mode of vibration is solved using …


On The Thermogravimetric Analysis Of Polymers: Polyethylene Oxide Powder And Nanofibers, Oriretan Omosola, Dorina M. Chipara, Mohammed Jasim Uddin, Karen Lozano, Mataz Alcoutlabi, Victoria Padilla-Gainza, Mircea Chipara May 2022

On The Thermogravimetric Analysis Of Polymers: Polyethylene Oxide Powder And Nanofibers, Oriretan Omosola, Dorina M. Chipara, Mohammed Jasim Uddin, Karen Lozano, Mataz Alcoutlabi, Victoria Padilla-Gainza, Mircea Chipara

Mechanical Engineering Faculty Publications

Thermogravimetric analysis of polyethylene oxide (powder and nanofibers obtained by force spinning water or chloroform solutions of polyethylene oxide) was studied using different theoretical models such as Friedman and Flynn-Wall-Ozawa. A semiempirical approach for estimating the “sigmoid activation energy” from the thermal degradation was suggested and confirmed by the experimental data on PEO powder and nanofibers' mats. The equation allowed for calculating a “sigmoid activation energy” from a single thermogram using a single heating rate without requiring any model for the actual complex set of chemical reactions involved in the thermal degradation process. For PEO (powder and nanofibers obtained from …


Model-Assisted Deep Learning Of Rare Extreme Events From Partial Observations, Anna Asch, Ethan Brady, Hugo Gallardo, John Hood, Bryan Chu, Mohammad Farazmanda Apr 2022

Model-Assisted Deep Learning Of Rare Extreme Events From Partial Observations, Anna Asch, Ethan Brady, Hugo Gallardo, John Hood, Bryan Chu, Mohammad Farazmanda

Mechanical Engineering Faculty Publications

To predict rare extreme events using deep neural networks, one encounters the so-called small data problem because even long-term observations often contain few extreme events. Here, we investigate a model-assisted framework where the training data are obtained from numerical simulations, as opposed to observations, with adequate samples from extreme events. However, to ensure the trained networks are applicable in practice, the training is not performed on the full simulation data; instead, we only use a small subset of observable quantities, which can be measured in practice. We investigate the feasibility of this model-assisted framework on three different dynamical systems (Rössler …


In-Situ Calibrated Digital Process Twin Models For Resource Efficient Manufacturing, David Adeniji, Julius Schoop Apr 2022

In-Situ Calibrated Digital Process Twin Models For Resource Efficient Manufacturing, David Adeniji, Julius Schoop

Mechanical Engineering Faculty Publications

The chief objective of manufacturing process improvement efforts is to significantly minimize process resources such as time, cost, waste, and consumed energy while improving product quality and process productivity. This paper presents a novel physics-informed optimization approach based on artificial intelligence (AI) to generate digital process twins (DPTs). The utility of the DPT approach is demonstrated in the case of finish machining of aerospace components made from gamma titanium aluminide alloy (γ-TiAl). This particular component has been plagued with persistent quality defects, including surface and sub-surface cracks, which adversely affect resource efficiency. Previous process improvement efforts have been restricted to …


Innovations In Engineering Education For Fast-Paced Virtual Summer Courses, Eleazar Marquez, Samuel Garcia Mar 2022

Innovations In Engineering Education For Fast-Paced Virtual Summer Courses, Eleazar Marquez, Samuel Garcia

Mechanical Engineering Faculty Publications

In this study, the recently developed CIRE (Communication, Initiation, Reduction, and Extension) pedagogical model was modified to generate an effective framework for a virtual, fast-paced summer engineering course in a private university in Texas. Transitioning to fully online courses in the wake of COVID-19 required rectifying traditional instructional methods to overcome challenges such as the lack of academic resources and established campus practices, while simultaneously ensuring the academic development of students. Thus, a pedagogical framework known as the CIRE model was recently designed and implemented in a Rigid Body Dynamics course, which according to the study, generated favorable results. To …


Enhanced Immunoprecipitation Techniques For The Identification Of Rna-Binding Protein Partners: Igf2bp1 Interactions In Mammary Epithelial Cells, Saja A. Fakhraldeen, Scott M. Berry, David J. Beebe, Avtar Roopra, Celia M. Bisbach, Vladimir S. Spiegelman, Natalie M. Niemi, Caroline M. Alexander Mar 2022

Enhanced Immunoprecipitation Techniques For The Identification Of Rna-Binding Protein Partners: Igf2bp1 Interactions In Mammary Epithelial Cells, Saja A. Fakhraldeen, Scott M. Berry, David J. Beebe, Avtar Roopra, Celia M. Bisbach, Vladimir S. Spiegelman, Natalie M. Niemi, Caroline M. Alexander

Mechanical Engineering Faculty Publications

RNA-binding proteins (RBPs) regulate the expression of large cohorts of RNA species to produce programmatic changes in cellular phenotypes. To describe the function of RBPs within a cell, it is key to identify their mRNA-binding partners. This is often done by crosslinking nucleic acids to RBPs, followed by chemical release of the nucleic acid fragments for analysis. However, this methodology is lengthy, which involves complex processing with attendant sample losses, thus large amounts of starting materials and prone to artifacts. To evaluate potential alternative technologies, we tested “exclusion-based” purification of immunoprecipitates (IFAST or SLIDE) and report here that these methods …


Amplitude And Wavelength Scaling Of Sinusoidal Roughness Effects In Turbulent Channel Flow At Fixed ReΤ, Sparsh Ganju, Sean C. C. Bailey, Christoph Brehm Feb 2022

Amplitude And Wavelength Scaling Of Sinusoidal Roughness Effects In Turbulent Channel Flow At Fixed ReΤ, Sparsh Ganju, Sean C. C. Bailey, Christoph Brehm

Mechanical Engineering Faculty Publications

Direct numerical simulations are performed for incompressible, turbulent channel flow over a smooth wall and different sinusoidal wall roughness configurations at a constant Reτ = 720. Sinusoidal walls are used to study the effects of well-defined geometric features of roughness-amplitude, a, and wavelength, λ, on the flow. The flow in the near-wall region is strongly influenced by both a and λ. Establishing appropriate scaling laws will aid in understanding the effects of roughness and identifying the relevant physical mechanisms. Using inner variables and the roughness function to scale the flow quantities provides support for Townsend’s hypothesis, …


Modification Of Superabsorbent Hydrogels For Industrial Wastewater Treatment, Md. Owaleur Rahman, Md. Abdul Halim, Anjan Deb, Shafi Ahmed, Md. Wasikur Rahman, N. C. Dafader, S. M. Nur Alam, Shahjalal Khandaker, Md. Jahangir Alam Feb 2022

Modification Of Superabsorbent Hydrogels For Industrial Wastewater Treatment, Md. Owaleur Rahman, Md. Abdul Halim, Anjan Deb, Shafi Ahmed, Md. Wasikur Rahman, N. C. Dafader, S. M. Nur Alam, Shahjalal Khandaker, Md. Jahangir Alam

Mechanical Engineering Faculty Publications

A breakthrough in superabsorbent hydrogel (SAH) preparation was studied in the current issue by blending potato starch and acrylic acid for wastewater treatment. Gamma irradiation source (60Co irradiation) was used to irradiate SAH from 1 to 10 kGy dose at room temperature (~27°C). The swelling ratio, water absorption, equilibrium water content, and gel fraction properties of the hydrogel were investigated. The as-prepared hydrogel treated with KOH (THG) showed excellent absorption capacity but less mechanical stability compared to untreated hydrogel (UHG). The gel fraction of treated SAH was slightly lower in methanol, but the utmost in water at 5 kGy infers …


Color Tunable Aerogels/Sponge-Like Structures Developed From Fine Fiber Membranes, Alexa Villarreal, Raul Barbosa, Saptasree Bose, Bhupendra B. Srivastava, Victoria Padilla-Gainza, Karen Lozano Feb 2022

Color Tunable Aerogels/Sponge-Like Structures Developed From Fine Fiber Membranes, Alexa Villarreal, Raul Barbosa, Saptasree Bose, Bhupendra B. Srivastava, Victoria Padilla-Gainza, Karen Lozano

Mechanical Engineering Faculty Publications

The development of macroscopic aerogels from 1D systems, such as nanofibers, has resulted in a novel pathway to obtain porous and lightweight architectures. In this work, bright green, red, and tunable color emitting aerogels were obtained with luminescent nanofibers as the precursor system. A simple, low cost, and environmentally friendly process is followed where luminescent fillers are encapsulated within fibers which were subsequently freeze-dried to form 3D aerogels and sponge-like structures. Moreover, the aerogels/sponge-like structures show higher photoluminescence intensity than the fiber mats due to an increase of porosity which provides higher and direct interaction with the fillers and therefore …


Volumetric Lattice Boltzmann Method For Wall Stresses Of Image-Based Pulsatile Flows, Xiaoyu Zhang, Joan Gomez-Paz, Xi Chen, James M. Mcdonough, Md Mahfuzul Islam, Yiannis Andreopoulos, Luoding Zhu, Huidan Yu Feb 2022

Volumetric Lattice Boltzmann Method For Wall Stresses Of Image-Based Pulsatile Flows, Xiaoyu Zhang, Joan Gomez-Paz, Xi Chen, James M. Mcdonough, Md Mahfuzul Islam, Yiannis Andreopoulos, Luoding Zhu, Huidan Yu

Mechanical Engineering Faculty Publications

Image-based computational fluid dynamics (CFD) has become a new capability for determining wall stresses of pulsatile flows. However, a computational platform that directly connects image information to pulsatile wall stresses is lacking. Prevailing methods rely on manual crafting of a hodgepodge of multidisciplinary software packages, which is usually laborious and error-prone. We present a new computational platform, to compute wall stresses in image-based pulsatile flows using the volumetric lattice Boltzmann method (VLBM). The novelty includes: (1) a unique image processing to extract flow domain and local wall normality, (2) a seamless connection between image extraction and VLBM, (3) an en-route …


Development Of Zinc Oxide/Hydroxyapatite/Poly(D,L-Lactic Acid) Fibrous Scaffold For Tissue Engineering Applications, Victoria Padilla-Gainza, Heriberto Rodríguez-Tobías, Graciela Morales, Antonio Ledezma-Pérez, Carmen Alvarado-Canché, Raúl Loera-Valencia, Cristóbal Rodríguez, Robert Gilkerson, Carlos Trevino De Leo, Karen Lozano Feb 2022

Development Of Zinc Oxide/Hydroxyapatite/Poly(D,L-Lactic Acid) Fibrous Scaffold For Tissue Engineering Applications, Victoria Padilla-Gainza, Heriberto Rodríguez-Tobías, Graciela Morales, Antonio Ledezma-Pérez, Carmen Alvarado-Canché, Raúl Loera-Valencia, Cristóbal Rodríguez, Robert Gilkerson, Carlos Trevino De Leo, Karen Lozano

Mechanical Engineering Faculty Publications

Scaffolds based on polymeric fibers represent an engaging biomedical device due to their particular morphology and similarity with extracellular matrices. The biggest challenge to use fibrous materials in the biomedical field is related to their favorable platform for the adhesion of pathogenic microorganisms. Therefore, their optimum performance not only depends on their bioactive potential but also on their antimicrobial properties. The aim of this work was the design of antimicrobial (zinc oxide, ZnO) and bioactive (hydroxyapatite, Hap) fibrous materials using poly(D, L-lactic acid) (PDLLA) as the polymer fiber substrate. Fiber based composite scaffolds were developed using the Forcespinning® technique. For …