Other Materials Science and Engineering Commons^™

Understanding The Metallic And Oxide Phases In Platinum-Based Bimetallic Heterogeneous Catalysts After High-Temperature Oxidation, Stephen John Porter Jr

Nanoscience and Microsystems ETDs

Platinum (Pt) and palladium (Pd) are critical components in diesel emission control systems, enabling the conversion of harmful pollutants under demanding conditions. However, Pt’s effectiveness is hindered by sintering under high-temperature oxidizing environments. This dissertation investigates how Pt and Pd evolve under oxidizing conditions at 800°C, highlighting their distinct thermodynamic behaviors and interactions. Using TEM, EDS, EELS, XRF, XRD, and EXAFS, we show that Pd suppresses Pt sintering by reducing the volatility of PtO₂, leading to the formation of stable particles. Both Pt and Pd are present in metallic and oxide states, forming biphasic 'Janus' particles with conjoined metal and …

Magnetically Impelled Arc Butt Welding And Straight Tube Butt Welding Analysis Of Boiler Grade Tube Joints, Santhosh Kumar S

Theses and Dissertations

Boiler-graded tubes of T11, T12, T91, and T92 materials with a thickness of 4.5 mm thick and 44.5 mm outer diameter were selected for the Straight Tube Butt Welding process using Hot Wire (STBW-HW) and Cold Wire (STBW-CW) conditions. Moreover, the research investigates and compares the welding characteristics of dissimilar T11 and T91 boiler-graded tubes using STBW - HW & Magnetically Impelled Arc Butt (MIAB) welding techniques. Similar and dissimilar welding was performed in STBW – HW & CW conditions.

In dissimilar welding, the tensile strength was higher in the T11-T91 STBWHW joints of 663 MPa than in the T12-T92 …

Pd-Based Hydrogen Separation Membranes Synthesized Via A Liquid-Phase Route, Chase W. Thompson

Chemical and Biological Engineering ETDs

Palladium (Pd) membranes have gained significant attention for their ability to selectively separate hydrogen, a critical process for clean energy applications such as fuel cells and hydrogen storage. However, challenges such as grain growth, sintering, hydrogen embrittlement, and film uniformity limit their scalability and long-term stability. This thesis focuses on the controlled synthesis, deposition, and stability of Pd nanoparticles to optimize membrane performance for hydrogen separation. This work investigates solution-phase synthesis of Pd nanoparticles, focusing on temperature, precursor concentration, and solvent composition as key variables influencing particle growth and dispersion. Pd membranes were fabricated using nanoparticle deposition onto porous supports, …

Synthesis And Characterization Of Temperature- And Ph-Responsive Pia-B-Pnipam@Fe3O4 Nanocomposites, Swati Kumari, Cayla Cook, Fatema Tarannum, Erick Salvador Vasquez-Guardado, Olufemi Ogunjimi, Keisha B. Walters

Chemical and Materials Engineering Faculty Publications

Stimuli-responsive polymers (SRPs) have garnered significant attention in recent decades due to their immense potential in biomedical and environmental applications. When these SRPs are grafted onto magnetic nanoparticles, they form multifunctional nanocomposites capable of various complex applications, such as targeted drug delivery, advanced separations, and magnetic resonance imaging. In this study, we employed a one-step hydrothermal method using 3-aminopropyltrimethoxysilane (APTES) to synthesize APTES-modified Fe₃O₄ nanoparticles (APTES@Fe₃O₄) featuring reactive terminal amine groups. Subsequently, via two consecutive surface-initiated atom transfer radical polymerizations (SI-ATRP), pH- and temperature-responsive polymer blocks were grown from the Fe₃O …

A Review On The Use Of Salt And Sugar As Natural Admixtures In Concrete, Noura A. Yassine, Lelian W. Elkhatib, Adel Elkordi, Mohammed Sonebi, Jamal Khatib

BAU Journal - Science and Technology

Due to the large increase in construction nowadays, the focus on the reduction of waste in the environment and saving cost becomes crucial. This issue, if solved, will conserve natural materials and make an eco-friendly environment. According to this, the use of natural materials, specifically in concrete/mortar, will shape a green and sustainable environment. One of the most used materials in construction is concrete where some additives like accelerators and retarders are added in order to enhance and modify some properties of concrete. These additives are beneficial and important to be used specifically in case of different weather conditions. Weather …

Magnetic Nanoparticles: Synthesis And Applications In Life Sciences, Kishore Chand, Erick Salvador Vasquez

Chemical and Materials Engineering Faculty Publications

Magnetic nanoparticles (MNPs) are multifunctional materials with superparamagnetic properties and tunable surface chemistries, making them valuable across diverse fields, such as biomedicine, environmental remediation, and agriculture. This review examines recent advancements in MNP synthesis, encompassing chemical, physical, and environmentally friendly methods while highlighting improvements in size, morphology, and composition control that enhance application-specific performance and environmental sustainability. The review discusses various architectures, including single-core, core–shell, hybrid composites, and stimuli–responsive systems, with an emphasis on their stability, scalability, and functionalization potential. In biomedical applications, MNPs show promise in targeted drug delivery, magnetic hyperthermia, and magnetic resonance imaging contrast enhancement, where biocompatibility, …

Systematic Review: Recent Developments In Magnetic-Nanoparticle-Based Dna Extraction, Stanley Evander Emeltan Tjoa, Mudasir Mudasir, Edi Suharyadi, Budi Setiadi Daryono

Makara Journal of Science

Deoxyribonucleic acid (DNA) is a research object for various molecular fields of study, and DNA extraction is a basic procedure in molecular biology laboratories. DNA extraction methods are evolving, from several steps using organic solvents to recent technology using magnetic nanoparticles as adsorbents for the purification step. The use of magnetic nanoparticles for DNA extraction is magnetizing because it is simple without heavy machinery, such as centrifugation and organic solvents. The application of this method is extensive and diverse. This systematic review summarizes current development trends for some aspects of this DNA extraction system from the magnetic nanoparticle synthesis method, …

Work In Progress: Exploring The Impact Of International Experiences On The Development Of Students’ Entrepreneurial Mindset, Olgha Bassam Qaqish, Marcia Pool, William H. Pennock, Erick Salvador Vasquez, Fahmidah Ummul Ashraf

Chemical and Materials Engineering Faculty Publications

International experiences, including collaborative online international learning (COIL) experiences that naturally increase accessibility, are of interest to many undergraduate students. These experiences provide educators a unique opportunity to develop a student's entrepreneurial mindset (EM). Additionally, hands-on experiences aligned with the National Academy of Engineering’s (NAE) grand challenge themes (Sustainability, Security, Health, and Joy of Living) support connections between the experience, disciplinary knowledge, multicultural awareness, and EM. Through this Work-in-Progress (WiP) study, we seek to answer: 1) How do international experiences influence undergraduate science and engineering students’ EM, and 2) How does the international experience modality (i.e., study abroad or COIL) …

Camino—Career Advancement, Mentorship, Inspiration, And Opportunities: A Stem K-12 Outreach Initiative, Hector A. Pulgar, Francisco Zelaya-Arrazabal, Erick Salvador Vasquez, Sebastian N. Martinez Lizana

Chemical and Materials Engineering Faculty Publications

CAMINO is a STEM program designed to promote career advancement, provide mentorship, give inspiration, and offer opportunities for K-12 Hispanic students located in East Tennessee. As part of the educational component of an NSF CAREER grant, the program launched in 2021 and is a collaboration between a research group from the University of Tennessee and one of the high schools with the largest Hispanic populations in the Knoxville Metropolitan area. These students from minority backgrounds may limit their aspirations and may not pursue higher education and/or professional development for numerous reasons, such as limited motivation, insufficient exposure to higher education, …

Entrepreneurially Minded Learning (Eml) Micromoment Activities Generated Using Students' Experiences In A Fluid Flow And Heat Transfer Course, Erick Salvador Vasquez, Megan Morin

Chemical and Materials Engineering Faculty Publications

The Entrepreneurially Minded Learning (EML) Framework involves the 3 C's: curiosity, connections, and creating value. Several design courses, open-ended assignments, and laboratory experiences can successfully lead to EML implementations. However, these implementations require extensive class time and instructor feedback, limiting their use in core engineering courses. Developing EML activities that are active, engaging, and rapid to deploy in a classroom setting can promote the sustained growth of an entrepreneurial mindset (EM). EML micromoment activities are emerging as a practical tool to facilitate the incorporation of the 3 Cs through rapid activity implementations that only last 2 – 30 minutes. These …

Shrinkage Study In Photopolymerisable Hybrid Sol-Gel Through Holographic Patterning, Jamshed Aftab, Izabela Naydenova, Tatsiana Mikulchyk

Articles

Photopolymerisation induced shrinkage of holographic materials is one of the main factors which needs to be considered for designing holographic optical elements (HOEs) with high accuracy in light redirection with maximum efficiency. This work studies the shrinkage in photopolymerisable hybrid sol-gel (PHSG) by examining the properties of volume transmission gratings recorded in PHSG layers. It explores both the dependence of shrinkage on the holographic grating parameters (thickness, spatial frequency, slant angle) and the effect of material aging. By using the fringe-plane rotation model, shrinkage is found to have the maximum value of 1.37 % at 765 lines/mm (19.36° slant angle) …

Thermal Modeling Techniques For Additively Manufactured Porous Metals, Lucas D. Rambo

Master's Theses

Advances in additive manufacturing have enabled the creation of metallic components with tailored porosity, offering design flexibility for thermal, structural, and fluid transport applications. This thesis investigates the effective thermal conductivity (ETC) of porous Inconel 625 (IN625) and Inconel-ceramic composites (IN625-RAM2) fabricated by Laser Powder Bed Fusion (LPBF) using Elementum 3D’s PermiAM technology. Experimental measurements of thermal conductivity using the laser flash method are compared to numerical models built from micro-computed tomography data. Simulations were performed using both finite element (FE) and finite volume (FV) methods to evaluate thermal transport in real microstructures. The study investigates the effects of micro- …

In-Situ Defect Detection In Selective Laser Melting Using Convolutional Neural Networks, Ethan Gaigalas

Master's Theses

This thesis develops and trains a convolutional neural network (CNN) to classify defects in metal parts produced by selective laser melting (SLM) using acoustic emission (AE) data. The model successfully identified porosity and standard build layers with high accuracy but consistently struggled to classify lack of fusion (LOF) defects, regardless of input type, normalization, or class count. These results suggest that while AE signals contain distinguishable features for certain defect types, LOF signals may be too subtle or inconsistent for reliable detection. The study addresses the ongoing challenge of in-situ quality monitoring in metal additive manufacturing, where defects like cracks, …

3d Printed Fixed Wing Aircraft Competition, Sidney E. Long, Mitchell Heise, Jack Bride, Daniel Salinas

Mechanical Engineering

Cal State LA and Arlington University, Texas are hosting the same 3D printed, fixed wing aircraft competition for 2025. Cal Poly requires a competitive plane that can adhere to each rule and be piloted remotely to achieve the longest time in the air. The plane must utilize solely 3D printing technology for the wings, body, and all other structures. The only off-the-shelf components can be the motor and electronics, as well as mechanical devices such as hinges.

Student-Led Video Podcasting In A Chemical Behavior Of Materials Course, Erick Salvador Vasquez

Chemical and Materials Engineering Faculty Publications

Video podcasts, or vodcasts, are a form of podcasting that combines video and audio to deliver various types of educational content effectively. To our knowledge, very few studies have focused on student-produced podcasting for learning technical engineering concepts. This study explores using student-created technical videos in a course on the chemical behavior of materials through three separate assignments. The first assignment centered on sustainability aspects. Students, divided into groups of three, were tasked to review two influential journal articles on plastic waste input into the ocean and metal recycling. Each group had to prepare and deliver a technical script about …

Energy Conversion Materials: Computational Design Of Electrocatalysts Toward Sustainable Energy Applications, Courtney M. Brea

Dissertations, Theses, and Capstone Projects

As the global-scale need for sustainable energy technologies emerges due to anthropogenic climate change, electrocatalysis plays a crucial role in facilitating many sustainable processes. Several heterogenous cathode materials can perform different electrochemical activities using water, oxygen, hydrogen, carbon dioxide to deliver renewable electricity and value-added chemicals. By using the density functional theory method, it is possible to explore the structural and electronic properties that govern a catalysts’ activity and selectivity. In this thesis, we start by exploring 48 reconstructed transition metal dichalcogenides edges (MX₂, M = Mo, W; X = S, Se, Te) for carbon dioxide reduction reaction …

Using Predictive Analytics To Reduce Small Business Cost Estimation Error, Diana Solt

Journal of Applied Packaging Research

Small and medium packaging companies generally employ the use of custom-developed quoting programs to bid goods and services. Custom bid programs (e.g. Excel) are used to capture the company-specific costs of production. The inputs of variable costs, such as machine rate and scrap rate, are critical to get correct; however, companies often rely on educated guesses and industry expertise to quote packaging products to end-users. Due to the guesswork involved there can be a financial difference between the quoted costs and actual costs. This variance is often the cause of significant lost dollars. Price, if not determined correctly, could negatively …

Low-Field Magnetoresistance In Nanocomposites Of La₀.₇Sr₀.₃Mno₃ And Metal Oxides, Nicholas K. Thiel-Hudson

University Scholar Projects

Pure La_0.7Sr_0.3MnO₃ (LSMO) exhibits colossal magnetoresistance (CMR) with large applied magnetic field over a narrow temperature range (intrinsic behavior), limiting its application to narrow temperature ranges. In contrast, the extrinsic CMR effect originates from inhomogeneities at larger length scales, such as grain boundaries and phase separation, where the structural features act as tunneling barriers, leading to a low-field magnetoresistance (LFMR) response, thereby expanding the application of LSMO into the low-field regime over a broader temperature range. In this work, the magnetotransport behavior of pure LSMO thin film is compared to the composite layered heterostructures of …

Thermal Characterization Of 3d Printing Materials For Increasing Insulation Potential And Practicality, Jackson H. Minnick

Mechanical Engineering Undergraduate Honors Theses

This study served as an exploration into the possible existence of a correlation between the infill lattice structure of a 3D printed wall section and the thermal performance of that sample as characterized by thermal conductivity measured in units of Watts per meter Kelvin. With the continual increase in the practicality, fidelity, and applicable fields of additive manufacturing, namely FDM 3D printing, research on specific print characteristics and their effects on the material and thermal characteristics of the part in question is steadily becoming more commonplace. Although the thermal conductivity of 3D printed wall sections as a function of infill …

Characteristics Of Carbonaceous Materials Synthesized From Palm Oil Empty Fruit Bunch Waste Using Ferrocene Catalyst, Ahmad Nabil Shahab, Adinda Izzatul Islam, Afif Wardana, Ilham Nur Dimas Yahya, Ary Yanuar Tri Amalia, Nofrijon Sofyan, Donanta Dhaneswara

Journal of Materials Exploration and Findings

The synthesis of carbonaceous materials for reduced graphene oxide (rGO) precursors using oil palm empty fruit bunches waste as a carbon source offers a sustainable solution for waste management in the palm oil industry while delivering high-performance materials. The oil palm empty fruit bunches were carbonized, followed by acid washing, pyrolysis with ferrocene (8%, 12%, and 16% variations), and ultrasonication to produce rGO. The structural, electronic, and morphological properties of the rGO were analyzed using various characterization techniques. The band gap values decreased with increasing ferrocene concentration, from 1.14 eV (8%) to 1.06 (16%), indicating enhanced electronic conductivity. XRD analysis …