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Full-Text Articles in Materials Science and Engineering

63rd Annual Rocky Mountain Conference On Magnetic Resonance Aug 2024

63rd Annual Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 63rd annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in the Copper Conference Center, Copper Mountain, Colorado, August 4-8, 2024.


Implementation Of Machine Learning Using Deep Neural Networks To Estimate The Failure Risk Caused By Leakage In Pressure Relief Devices, Adi Yudho Wijayanto, Yossi Andreano, M. Ali Yafi Rizky, Dedi Priadi Aug 2024

Implementation Of Machine Learning Using Deep Neural Networks To Estimate The Failure Risk Caused By Leakage In Pressure Relief Devices, Adi Yudho Wijayanto, Yossi Andreano, M. Ali Yafi Rizky, Dedi Priadi

Journal of Materials Exploration and Findings

The primary objective of deploying Pressure Relief Device (PRD) equipment is to ensure the safety of pressure vessels within a pressurized system. Over time, PRD equipment may degrade and fail to perform its intended function, which must be identified as a failure mode. To mitigate potential risks associated with this, it is recommended that an approach such as risk-based inspection (RBI) be implemented. Despite the widespread adoption of RBI, the method relies on qualitative techniques, leading to significant variations in equipment risk assessments. This study proposes a novel risk analysis method that uses deep learning-based machine learning to develop a …


Inspection Planning Of Subsea Pipeline Using Risk-Based Inspection, Ni Luh Triska Adelia, Badrul Munir, Johny Wahyuadi Soedarsono Aug 2024

Inspection Planning Of Subsea Pipeline Using Risk-Based Inspection, Ni Luh Triska Adelia, Badrul Munir, Johny Wahyuadi Soedarsono

Journal of Materials Exploration and Findings

Pipelines are an important tool in oil and gas exploration. Pipeline is a transmission and liquid collection lines, including their accessories, which transport fluids from one plant to another. In transmission and collection process, there is a possibility of failure which can have minor to major impact on personnel injury, the environment and interrupt the business process. To maintain safety and to prevent accidents, the source and cause of failure needs to be calculated. Risk-based inspection (RBI) is a method that can be used to calculate the risk and determine the inspection planning both schedule and method, by combining the …


Effect Of Impurities In Supercritical Co2 Environment On Steel Corrosion Behavior – An Overview, Shilla Rizqi Widianto, Johny Wahyuadi Soedarsono, Rini Riastuti, Badrul Munir Aug 2024

Effect Of Impurities In Supercritical Co2 Environment On Steel Corrosion Behavior – An Overview, Shilla Rizqi Widianto, Johny Wahyuadi Soedarsono, Rini Riastuti, Badrul Munir

Journal of Materials Exploration and Findings

Carbon capture, utilization, and storage (CCUS) technology is one of the available technologies to reduce presence of greenhouse gasses. Implementation of CCUS technology strongly relates with the CO2 transportation from the capturing facility to the storage in the geological reservoir. The most economical method for large-scale and long-distance CO2 transportation is using pipeline in supercritical phase. Moreover, presence of impurities such as water, O2, SO2, H2S, NO2 may cause detrimental effect towards carbon steel pipeline. This paper intends to provide an initial information for supercritical CO2 pipeline material selection, which …


Feasibility Study Of Using Energy Extracted From The Process Of Electrochemically Consumed Of Al 2024 For Powering Daily Used Electric Car, Yanuar Mohamad Marda, Rini Riastuti, Muhammad Hamka Ibrahim Aug 2024

Feasibility Study Of Using Energy Extracted From The Process Of Electrochemically Consumed Of Al 2024 For Powering Daily Used Electric Car, Yanuar Mohamad Marda, Rini Riastuti, Muhammad Hamka Ibrahim

Journal of Materials Exploration and Findings

Usage of green energy for transportation has become important due to the contribution of transportation activity to climate change. Electrochemical energy has been used as a source of green energy. The objective of this work is to evaluate sufficiency of energy provided by electrochemically consumed Al 2024 for supplying energy to daily used PHEV electric car. Study of previous articles, observation of typical amount of energy required, electrochemical galvanic cell experiments, and simple calculations have been conducted to determine produced energy feasibility. Electrical energy produced by consuming 340 gr of Al 2024 in galvanic cells has the total lifetime of …


Maintenance Notes To Improve The Reliability Of Wheel Flange Failure For Overhead Crane, Fakhri Burhanuddin, Akhmad Herman Yuwono Aug 2024

Maintenance Notes To Improve The Reliability Of Wheel Flange Failure For Overhead Crane, Fakhri Burhanuddin, Akhmad Herman Yuwono

Journal of Materials Exploration and Findings

Overhead traveling cranes in the industry have utility workload classifications and require high standards of safety and reliability by mobilizing lifting and transporting capacity variants of steel products, equipment, and other supports. The crane wheels are the main support in moving the end carriage so that the crane can work according to its function. Failures in the operation and maintenance cycle have occurred. Therefore, proper repair and maintenance methods are highly needed to restore the original design function to its working integrity. Logic tree analysis was used to breakdown all causes of failure; thus, mitigation was performed by carrying out …


Hollow Connecting Rod Thin Wall Austempered Ductile Iron (Twadi) For Manufacturing Light Weight Components, Ricardina Freitas Da Silva, Bambang Suharno, Rianti Dewi Sulamet-Ariobimo Aug 2024

Hollow Connecting Rod Thin Wall Austempered Ductile Iron (Twadi) For Manufacturing Light Weight Components, Ricardina Freitas Da Silva, Bambang Suharno, Rianti Dewi Sulamet-Ariobimo

Journal of Materials Exploration and Findings

Efforts made by the automotive industry to reduce energy consumption have encouraged researchers to carry out various studies. One way is to make components lighter by casting thin wall austempered ductile iron (TWADI). Reducing the weight of components such as connecting rods (conrod) will result in lower energy consumption, but provided that these components still meet standards in terms of mechanical properties and microstructure or even exceed them. In this research, design optimization was applied to conrod by making the area I-beam zero mm (hollow), with hope that it can replace conrod Vespa PX-150. While the manufacturing process is divided …


Analysis Risk Based Inspection Api 581 On Lpg Spherical Tank At Pt. Xyz, Sigit Trahmawan, Eddy Sumarno Siradj, Jaka Fajar Fatriansyah Aug 2024

Analysis Risk Based Inspection Api 581 On Lpg Spherical Tank At Pt. Xyz, Sigit Trahmawan, Eddy Sumarno Siradj, Jaka Fajar Fatriansyah

Journal of Materials Exploration and Findings

Liquified petroleum gas (LPG) spherical tanks are pressure vessel equipment for storing fuel gas products. The high pressure along with the fuel gas inside as flammable and combustible substance means that this equipment might result major accident hazard such as explosion, fires and environmental pollution. This study is aimed calculated and mitigate risk on 500 metric ton capacity LPG spherical tank using Risk-based inspection (RBI) analysis method that makes risk as its foundation. This RBI method uses quantitative analysis referring to API 581 to determine the risk of LPG Spherical Tank by determining the probability of failure (PoF) and the …


Root Cause Analysis Of Leakage Tube Boiler: A Study Case, Lydia Kartika Basaria Sitompul, Dedi Priadi Aug 2024

Root Cause Analysis Of Leakage Tube Boiler: A Study Case, Lydia Kartika Basaria Sitompul, Dedi Priadi

Journal of Materials Exploration and Findings

Oil and gas industry can have catastrophic implications for human life, the environment, and the economy. This paper investigated failure analysis using root cause analysis especially for boiler tube leakage of Heat Exchanger. Identify the issue using microscopic examination and energy dispersive x-ray analysis were conducted on the tube inside and outside surface to determine root cause of the failure. The formation of a protective film in the aluminum-brass tube during the starting stage is very important for ensuring adequate film protection throughout the service life of the heat exchanger. During this stage, exposure to unpolluted water is essential. The …


Lifetime Prediction Of Pan Feeder Based On 3d Laser Scanning For Wear Assessment, Nony Maulidya, Dedi Priadi, D. Rizal Asral Aug 2024

Lifetime Prediction Of Pan Feeder Based On 3d Laser Scanning For Wear Assessment, Nony Maulidya, Dedi Priadi, D. Rizal Asral

Journal of Materials Exploration and Findings

Apron feeder is one of stages in crushing circuit to convey material in short distance. Pan flight is the main component of apron feeder that is severely exposed to wear mechanism due to its direct contact with open cut abrasive ore. With this operating environment of apron feeder, regular maintenance and inspection must be conducted to assess wear rate of pan’s surface to maintain equipment availability and provide information and sign before the equipment undergoes severe and sudden degradation. 3D laser scanning is method used in this study as Non-Destructive Testing (NDT) based inspection. The aim of using 3D scanning …


Uncertainty Quantification In Machine Learning Models Via Gaussian Process Regression: A Comparative Study, Ayorinde E. Olatunde, Weiqi Yue, Pawan K. Tripathi, Roger H. French, Anirban Mondal Aug 2024

Uncertainty Quantification In Machine Learning Models Via Gaussian Process Regression: A Comparative Study, Ayorinde E. Olatunde, Weiqi Yue, Pawan K. Tripathi, Roger H. French, Anirban Mondal

Faculty Scholarship

As the use of Machine learning models in science and engineering continues to increase, there is an increasing need for quantifying the uncertainties inherent in the predictions of these models. The more complex a model is, the more the uncertainties in its predictions increase. Amongst the plethora of methodologies used in quantifying uncertainties lies Gaussian Process Regression (GPR). GPR surmounts some of the popular shortfalls of other state-of-the-art methodologies. Although GPR has some quick wins in its application for uncertainty quantification, it is plagued with some shortfalls, such as scalability issues when the feature space increases as well as an …


Degradation Study Of Single Crystal Barium Titanate Capacitors Under Harsh Environment, Menglin Wang Aug 2024

Degradation Study Of Single Crystal Barium Titanate Capacitors Under Harsh Environment, Menglin Wang

Electrical Engineering Theses and Dissertations

Capacitors are critical for voltage source converter functionality. DC-link capacitors are known to have reliability issues. Resistance degradation at high temperatures is one of the primary failure modes in capacitors. The overall goal of this program is to improve the understanding of high voltage breakdown and resistance degradation in high dielectric constant inorganic ceramic capacitors, using single crystal BaTiO3 as a model system to understand the impact and control of oxygen vacancy migration to maximize the long-term reliability of high voltage inorganic multi-layer ceramic capacitors, which allows higher frequency operation, reducing the size and cost of passive components in …


Knowledge Management Of Historical Data: Ontology Development For Chemical Reactions, Quynh D. Tran, Alexander Harding Bradley, Balashanmuga Priyan Rajamohan, Jonathan E. Gordon, Van D. Tran, Kiefer Lin, Erika I. Barcelos, Laura S. Bruckman, Roger H. French Aug 2024

Knowledge Management Of Historical Data: Ontology Development For Chemical Reactions, Quynh D. Tran, Alexander Harding Bradley, Balashanmuga Priyan Rajamohan, Jonathan E. Gordon, Van D. Tran, Kiefer Lin, Erika I. Barcelos, Laura S. Bruckman, Roger H. French

Researchers, Instructors, & Staff Scholarship

Knowledge management of the literature and historical data is critical to accelerated drug and materials discovery. Currently, literature knowledge is scattered in journal articles in various formats: diagrams, texts, plots, etc. Historical data from past experiments are saved in a number of local computers under confusing folder structures with ambiguous file names. To manage and organize historical data and knowledge, our group (SDLE) at CWRU follows FAIR (Findable, Accessible, Interoperable, Reusable) principles, which outline the best practices for data stewardship and data provenance, and ontology, a formal representation of terms and concepts and their relationships, as a tool to improve …


A Fair Ontology For Aps Beamline Experiments, Gabriel Ponón, Balashanmuga Priyan Rajamohan, Mohommad Redad Mehdi, Finley Holt, Erika Barcelos, Pawan K. Tripathi, Roger H. French Aug 2024

A Fair Ontology For Aps Beamline Experiments, Gabriel Ponón, Balashanmuga Priyan Rajamohan, Mohommad Redad Mehdi, Finley Holt, Erika Barcelos, Pawan K. Tripathi, Roger H. French

Student Scholarship

Data produced at the 1-ID beamline APS are often serialized in large, disconnected tables, which can impede the effective reuse and replication of analysis performed for cutting edge research and instrumentation conducted at the facility. This poster describes an alternative approach of utilizing component-based FAIR (Findable, Accessible, Interoperable, and Reusable) ontologies as a framework for organizing and connecting experimental variables. Three packages were developed to facilitate the creation and connection of component ontologies into a fully connected FAIR ontology for an experiment. An ontology-based workflow is also discussed for beamline scientists and users to visualize and connect collected values alongside …


Stability, Mechanical Properties, And High-Pressure Structural Modifications Of Some Industrially Relevant Metallic Glasses, Alexander George Aug 2024

Stability, Mechanical Properties, And High-Pressure Structural Modifications Of Some Industrially Relevant Metallic Glasses, Alexander George

Graduate Theses & Non-Theses

Metallic glasses are metal-based alloys that have an amorphous structure and glass transition behavior as a result of being cooled rapidly enough to suppress crystal nucleation and growth[1]. Metallic glasses have been formed with two to eight constituents[2][3][4]; however, the most stable glass-forming systems typically contain four or more elements. With few exceptions, metallic glass-forming alloys are extremely unstable, requiring cooling rates on the order of 108-10-2 K/s to form a glassy sample. This instability translates to reheating, where onset crystallization temperatures infrequently exceed the glass transition by more than 100K. Strong glass-forming ability typically occurs over …


Solar Process Heat Pyrolysis, Maxwell Triepke Aug 2024

Solar Process Heat Pyrolysis, Maxwell Triepke

Graduate Theses & Non-Theses

Solar process heat pyrolysis mobilizes the production of biochar via selective solar absorbance. Mobilization allows for the production of pyrolysis products at the location of the biomass source while eliminating the need for infrastructural power to operate the reactor. Traditionally, the implementation of economies of scale has led to large, permanent biochar production facilities; however, biochar feedstock is often in remote locations or stockpiled temporarily in mill/forestry operation locations. Modular reactors are important to eliminate feedstock location, transportation, and variability limitations. Previous work at Montana Technological University’s CHAR Laboratory has developed two lab scale modular, both tethered to infrastructural power. …


Radiation-Tolerant Thin-Film Reference Electrodes And Potentiometric Sensors, Bingyuan Zhao, Alexander Wei Aug 2024

Radiation-Tolerant Thin-Film Reference Electrodes And Potentiometric Sensors, Bingyuan Zhao, Alexander Wei

Department of Chemistry Faculty Publications

The integration of electronic sensors into single-use systems for bioprocessing is challenged by their sensitivity to sterilizing γ-irradiation. This challenge also applies to reference electrodes (REs), whose potentials may be destabilized upon ionization and drift over time. Here we evaluate the performance of thin-film Ag/AgCl REs over a two-month window following γ-ray sterilization using a 60Co source. γ-REs display a characteristic voltage decay function ascribed to the dissipation of radiation-induced charge defects, and exhibit long-term potentiometric stability when stored in phosphate-buffered saline (PBS) with a 95% confidence interval of 4 mV over 60 days. γ-REs have a mean insensitivity (inertness) …


Computational Fluid Dynamics Modeling Of 12.25” Horizontal Wellbores To Identify The Effects Of Pipe Rotation On Cuttings Transport Efficiency, David Rathgeber Aug 2024

Computational Fluid Dynamics Modeling Of 12.25” Horizontal Wellbores To Identify The Effects Of Pipe Rotation On Cuttings Transport Efficiency, David Rathgeber

Graduate Theses & Non-Theses

As global demand for oil and gas continues to rise alongside pressures to curb climate change, Exploration and Production (E&P) companies look to reduce their surface footprint and increase drilling efficiency through longer horizontal well drilling. In addition, the depletion of conventional reservoirs is causing E&P companies to target more difficult reservoirs, often miles offshore (Gupta et al., 2014; Meader et al., 2000a). The increased horizontal reach of these wells often leads to increased challenges in adequate hole cleaning during drilling operations. Efficient hole cleaning becomes a greater challenge in high-angle wells, with gravitational forces causing pipe eccentricity, flow channeling, …


Development And Structural Origin Of Stretchable Semiconducting Polymers And Composites, Yunfei Wang Aug 2024

Development And Structural Origin Of Stretchable Semiconducting Polymers And Composites, Yunfei Wang

Dissertations

Stretchable semiconductors are pivotal in advancing wearable and implantable electronics, with those boasting both high stretchability and self-healing capabilities being especially significant for a myriad of wearable applications. In this dissertation, we developed an extremely soft, highly stretchable, and self-healing elastomer based on H-bonding crosslinked amide-functionalized polyisobutylene (PIB-amide). When blended with a high-performance conjugated diketopyrrolopyrrole (DPP-T) polymer, the composite exhibits unprecedented stretchability, exceptionally low elastic modulus, and an innate ability to self-heal at room temperature.

The morphology of conjugated polymer/elastomer semiconducting composites have significant impacts on electrical and mechanical properties Further investigations focused on manipulating the phase separation size in …


Surface Patterning On Zirconia Dental Implants Via Laser-Induced Shockwave Imprinting, Inomjon Majidov Aug 2024

Surface Patterning On Zirconia Dental Implants Via Laser-Induced Shockwave Imprinting, Inomjon Majidov

Masters Theses & Specialist Projects

Zirconia is rapidly becoming a preferred alternative to titanium in dental applications, primarily due to its aesthetic resemblance to natural teeth. This material’s tooth-like color avoids the aesthetic issues associated with the grey metal tint of titanium implants. Additionally, zirconia is hypoallergenic, making it an ideal choice for patients with metal sensitivities or allergies. Despite these advantages, zirconia generally exhibits lower biocompatibility and osseointegration compared to titanium implants. This study investigates laser-assisted, controlled imprinting technique on zirconia surfaces to enhance these properties. Our research used zirconia pellets, produced from powdered monoclinic zirconia pressed in a pellet press machine. Two methods …


Unrefined And Milled Ilmenite As A Cost-Effective Photocatalyst For Uv-Assisted Destruction And Mineralization Of Pfas, Eustace Y. Fernando, Zhiming Zhang Aug 2024

Unrefined And Milled Ilmenite As A Cost-Effective Photocatalyst For Uv-Assisted Destruction And Mineralization Of Pfas, Eustace Y. Fernando, Zhiming Zhang

Henry M. Rowan College of Engineering Departmental Research

Per- and polyfluoroalkyl substances (PFAS) are fluorinated and refractory pollutants that are ubiquitous in industrial wastewater. Photocatalytic destruction of such pollutants with catalysts such as TiO2 and ZnO is an attractive avenue for removal of PFAS, but refined forms of such photocatalysts are expensive. This study, for the first time, utilized milled unrefined raw mineral ilmenite, coupled to UV-C irradiation to achieve mineralization of the two model PFAS compounds perfluorooctanoic acid (PFOA) and perfluoro octane sulfonic acid (PFOS). Results obtained using a bench-scale photocatalytic reactor system demonstrated rapid removal kinetics of PFAS compounds (>90% removal in less than 10 …


Synergistic Strategies In Hybrid Mxed Matrix 3d Printing Of Thermoplastics & Thermosets: Design, Manufacturing, And Materials Development., Saleh Akram Khanjar Aug 2024

Synergistic Strategies In Hybrid Mxed Matrix 3d Printing Of Thermoplastics & Thermosets: Design, Manufacturing, And Materials Development., Saleh Akram Khanjar

Electronic Theses and Dissertations

Composite manufacturing and mixed matrix structures have been produced using traditional manufacturing processes for various industrial applications due to their high mechanical properties to material weight and cost ratio. However implementation of composite and mixed matrix manufacturing with advanced manufacturing such as additive manufacturing is limited due to the hardware limitations of current 3d printing technologies and materials available for 3D printing applications. This work has developed and investigated a new hybrid 3D printing manufacturing process utilizing a variety of material systems (thermoplastic – thermoset, thermoplastic – thermoplastic, thermoset – thermoset, thermoplastic – thermoplastic – thermoset). This study developed thermoplastic …


Settingsorder Article Reprints Open Accessarticle A Model To Account For The Effects Of Load Ratio And Hydrogen Pressure On The Fatigue Crack Growth Behavior Of Pressure Vessel Steels, Ashok Saxena, Kip O. Findley Aug 2024

Settingsorder Article Reprints Open Accessarticle A Model To Account For The Effects Of Load Ratio And Hydrogen Pressure On The Fatigue Crack Growth Behavior Of Pressure Vessel Steels, Ashok Saxena, Kip O. Findley

Mechanical Engineering Faculty Publications and Presentations

A phenomenological model for estimating the effects of load ratio R and hydrogen pressure PH2 on the hydrogen-assisted fatigue crack growth rate (HA-FCGR) behavior in the transient and steady-state regimes of pressure vessel steels is described. The "transient regime" is identified with crack growth within a severely embrittled zone of intense plasticity at the crack tip. The "steady-state" behavior is associated with the crack growing into a region of comparatively lower hydrogen concentration located further away from the crack tip. The model treats the effects of R and PH2 as being functionally separable. In the transient …


Synthesis Of Silica-Encapsulated Myristic Acid Phase-Change-Assisted Nanocapsules For Thermal Management Applications, Muhammad Ghufran, David Huitink Aug 2024

Synthesis Of Silica-Encapsulated Myristic Acid Phase-Change-Assisted Nanocapsules For Thermal Management Applications, Muhammad Ghufran, David Huitink

Mechanical Engineering Faculty Publications and Presentations

Myristic acid-based silica (MA/SiO2) nano-encapsulated phase change materials (NePCMs) were synthesized by the sol–gel process. Five different samples of the MA/SiO2 nanocapsules were prepared by varying the mass of the myristic acid. The nanocapsules were characterized by Fourier transform infrared spectrophotometer (FTIR), X-Ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), energy dispersive X-ray (EDX), and dynamic light scattering (DLS). These characterization techniques confirmed the successful encapsulation of the myristic acid inside the silica shell. The maximum latent heat was found to be 114.46 J/g for the sample which was prepared with 25 g myristic …


Smart Automatic Modal Hammer Predictor–Corrector Approach For Accurate Excitation Of Dynamical Systems, Mohammad Nasr Aug 2024

Smart Automatic Modal Hammer Predictor–Corrector Approach For Accurate Excitation Of Dynamical Systems, Mohammad Nasr

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

This research introduces an innovative solution that revolutionizes the study of linear and nonlinear dynamical systems—a smart automatic modal hammer. With its affordability and intelligent capabilities, this automatic modal hammer becomes an invaluable tool for research and industry, enabling repeatable strikes with precise force control. This system's significance becomes particularly evident when studying nonlinear systems, which heavily rely on the excitation level for their dynamics. By offering a cost-effective design this proposed system proves to be robust in accelerating research on nonlinear dynamics, providing researchers with an efficient and accessible means to delve deeper into these complex systems. The proposed …


Ultrasonic Nondestructive Quantification Of Case Depth In Railroad Bearing Components, Trevor K. Adelung Aug 2024

Ultrasonic Nondestructive Quantification Of Case Depth In Railroad Bearing Components, Trevor K. Adelung

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

While in service, railroad bearings must withstand large loads to ensure smooth operation. These large loads can lead to failure due to rolling contact fatigue (RCF), for which small cracks initiate just beneath the surface of the components. As a preventative measure, bearings are manufactured with a hardened surface layer called the effective case depth (ECD). Current methods in industry use destructive hardness testing to quantify the ECD. While accurate, this method is costly and time consuming. Ultrasonic nondestructive testing would provide a more efficient and cost-effective method to determine ECD. In this thesis, diffuse ultrasonic shear backscatter was used …


Studies Of Exotic Electronic, Optical, And Electrochemical Properties In Nanoparticle Assembly And Graphene, Jay Min Lim Aug 2024

Studies Of Exotic Electronic, Optical, And Electrochemical Properties In Nanoparticle Assembly And Graphene, Jay Min Lim

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

It is well known that exotic properties and phenomena emerge as structural dimensions shrink to nanoscales. We self-assembled one-dimensional chains of gold nanoparticles in solution and quantified the growth process by monitoring the redshift of localized surface plasmon resonance (LSPR). Curiously, the redshift stopped while the chains continued to rearrange as manifested by gradual reduction in the LSPR peak. Using electromagnetic simulations, we quantitatively explained the phenomena as a rapid “addition-polymerization” followed by a sharp transition to “condensation-process.” Next, recognizing the significant electric field enhancement in the interparticle gap, a photoluminescent-active Eu3+ ion was used to probe Surface-Enhanced Photoluminescence …


Understanding And Tuning Magnetism In Van Der Waals-Type Metal Thiophosphates, Rabindra Basnet, Jin Hu Aug 2024

Understanding And Tuning Magnetism In Van Der Waals-Type Metal Thiophosphates, Rabindra Basnet, Jin Hu

Physics Faculty Publications and Presentations

Over the past two decades, significant progress in two-dimensional (2D) materials has invigorated research in condensed matter and material physics in low dimensions. While traditionally studied in three-dimensional systems, magnetism has now been extended to the 2D realm. Recent breakthroughs in 2D magnetism have attracted substantial interest from the scientific community, owing to the stable magnetic order achievable in atomically thin layers of the van der Waals (vdW)-type layered magnetic materials. These advances offer an exciting platform for investigating related phenomena in low dimensions and hold promise for spintronic applications. Consequently, vdW magnetic materials with tunable magnetism have attracted significant …


Enhanced Optical And Infrared Activity Of Nanosphere Dimers Attributed To Dimer Geometry, D. Keith Roper, Jin-Woo Kim, Ricardo R. Romo, Joseph Batta-Mpouma Aug 2024

Enhanced Optical And Infrared Activity Of Nanosphere Dimers Attributed To Dimer Geometry, D. Keith Roper, Jin-Woo Kim, Ricardo R. Romo, Joseph Batta-Mpouma

Biological and Agricultural Engineering Faculty Publications and Presentations

Enhanced optical and infrared activity of subwavelength metal nanoparticles is key to their use in optoelectronics, spectroscopy, and sensing. The present work compared spectra of nanosphere dimers merged by centrifuging gold nanospheres with corresponding simulated nanoscale dimers. Geometric features of the nanosphere dimers were related to corresponding optical and near-infrared activity through simulation. Differences in optical and infrared activity of the nanosphere dimers were largely attributable to changes in the radius of the nanosphere and the radius of the conductive junction between merged nanospheres. The features observed in the experimental spectra were attributed to a select number of dimers exhibiting …


Understanding The Microstructure And Tribological Performance Of Cocrfeni-Based High Entropy Alloys, Ali Azarmi Aug 2024

Understanding The Microstructure And Tribological Performance Of Cocrfeni-Based High Entropy Alloys, Ali Azarmi

All Theses

Due to their higher wear resistance compared to conventional alloys, high entropy alloys (HEAs) are now being considered as candidates for parts undergoing sliding contact during their lifetimes. While the engineering field has built some knowledge related to the performance of selected high entropy alloys, such as the CoCrFeNi alloy, more research is needed to determine if (how) expansions from four to five principal alloying elements alter the performance compared to the initial alloy. In this study, we started this research effort by investigating the relative performance of CoCrFeNiMn and CoCrFeNiTi with respect to CoCrFeNi. The two primary alloying elements …