Engineering Commons^™

The Changes In Microstructural Features And Physical Properties Of Ceramic Matrix Composite Bonding Tools Under Ultrasonic Service, Apirat Theerapapvisetpong, Karn Serivalsatit, Wuttichai Reainthippayasakul, Wantanee Buggakupta

Journal of Metals, Materials and Minerals

Tape automated bonding (TAB) process plays a key role in the production of disk drives, microchips and other microelectronics components. Such tools should sustain their structures and properties throughout ultrasonic operation and are expected to last until reaching the targeted numbers of TAB cycles. This project aims to evaluate the changes in microstructures and physical properties of the bonding tools under ultrasonic service. Three commercial waffle-type tools from different suppliers were focused, namely Tool A, Tool B and Tool C. They provide different levels of bonding efficiency up to 50k cycles under relatively similar ultrasonic practice. Non-destructive and destructive testing …

Synthesis Of Sic Nanowires On Biochar Surfaces By A Simple Direct Method, Wasana Khongwong, Chumphol Busabok, Piyalak Ngernchuklin

Journal of Metals, Materials and Minerals

Demand for air filters is crucially required due to PM 2.5. So, SiC nanowire networks are directly grown on biochar surfaces that serve strength and filtering purposes. The nanowires were prepared by spraying silicon powder on Lesser bulrush and Grey sedge biochars which acted as carbon sources and heating up to 1300℃ to 1500℃ for 1 h in Ar atmosphere. As a result, silicon powder evaporated and diffused on biochar surfaces. Meanwhile, CO vapor was generated from biochar reacted with O2 in the chamber. The evaporated silicon reacted with both C(s) and CO(g) to form cubic SiC nanowires. At the …

Growth Of Proton Conducting Strontium Cerate Composites, C. K. Shilpa, S. V. Jasira, V. P. Veena, K. M. Nissamudeen

Journal of Metals, Materials and Minerals

The increased population and modern way of life have greatly depleted the effectiveness of traditional energy production methods. There is a strong demand for environmentally friendly and renewable alternatives to replace the old systems. Sustainable energy production systems have emerged as a vital replacement for the conventional use of fossil fuels. Among these, solid oxide fuel cells (SOFCs) play a significant role. Recently, researchers have developed electrolyte components for SOFCs using proton-conducting perovskites with excellent conductivity. This critical assessment presents a yearly overview of innovative strategies for utilizing doped strontium cerate perovskites in energy production systems, a novel approach. The …

Review Of Materials, Functional Components, Fabrication Technologies And Assembling Characteristics For Polymer Electrolyte Membrane Fuel Cells (Pemfcs) – An Update, Arun Daya, Arputharaj Samson Nesaraj

Journal of Metals, Materials and Minerals

Fuel cells use electrochemical processes to transform the chemical energy of a fuel into electrical energy, which is a key enabler for the shift to an H2-based economy. Because of their high energy conversion efficiency and low pollution emissions, fuel cells with polymer electrolyte membranes (PEMFCs) are regarded as being in frontline of commercialization for the transportation and automotive industries. However, there are two major hurdles to their future commercialization: cost and durability, which promote basic study and development of their components. In this article, we reviewed the materials, functional components, fabrication technologies and assembling characteristics related to PEMFCs. Platinum's …

Structure And Chemical Durability Improvement Of Alkali Silicate Glass By Zirconium Dioxide And Erbium Oxide Addition, Ativit Denprawat, Kittipong Sinwanasarp, Pinit Kidkhunthod, Nattapol Laorodphan, Worapong Thiemsorn

Journal of Metals, Materials and Minerals

Glass structure tailoring of alkali silicate glasses by addition of ZrO2 and Er2O3 is found to enhance the chemical durability of glasses. ZrO2 (x ranged between 5 mol% to 15 mol%) and Er2O3 (y ranged between 0.5 mol% to 1.5 mol%) were used to replace SiO2 and Na2O, respectively, in the glasses with the nominal composition of 10Li2O-(15-y)Na2O-10CaO-(65-x)SiO2-xZrO2-y Er2O3. The samples were prepared by conventional melt quenching technique. The structures of produced glasses were examined by X-ray absorption spectroscopy (XAS) and Raman spectroscopy. XAS spectra demonstrated that the oxidation numbers of Zr and Er ions were +4 and +3, respectively. …

Quantum-Based First-Principles Study Of Gas Molecules (O2 , Co2 , No2 ) Interaction On Monolayer Germanene, Arief Hermanto, Harmon Prayogi, Ari Dwi Nugraheni, Juliasih Partini, Sholihun Sholihun

Journal of Metals, Materials and Minerals

We perform calculations of the adsorption energy of O2, CO2, and NO2 molecules on germanene by using the density functional theory (DFT). We find two favorable configurations for O2, the U-site and V-site configurations with similar adsorption energies of -4.10 and -4.32 eV. As for NO2, we find two favorable configurations, the T-site and DB-site configurations. The T-site configuration is 0.98 eV more stable than the IB-site one, and both configurations are chemically adsorbed by germanene. On the contrary for CO2, we find a T-site configuration with adsorption energy of 0.42 eV and the configuration physically adsorbed by germanene.

Synthesis And Modification Of Nickel Hydroxide Particle Synthesized By Self-Assembly And Electron Beam Irradiation Technique For Photocatalyst Activity, Narisara Saechin, Sumitra Sripho, Thitirat Rattanawongwiboon, Sakchai Laksee, Pattra Lertsarawut, Wilasinee Kingkam, Sarute Ummartyotin

Journal of Metals, Materials and Minerals

The purpose of this work is to study the methyl orange removal of Ni(OH)2 nanoparticles. The photo-catalyst activity is investigated based on UV lamp of 18 watt. Ni(OH)2 is synthesized by a self-assembly process and then exposed to electron beam radiation at 10 MeV energy with various doses ranging from 50 kGy to 500 kGy. The properties of Ni(OH)2 nanoparticles are then evaluated. No significant change of functional group and percent of crystallinity are observed. The morphology is uniformly presented as a plate-like. The specific surface area, pore size and pore volume are reduced. Point of zero charge confirmed that …

Effect Of Calcination Frequency On The Thermoelectric Properties Of Ti Doped Cucro By Solid State Method, Doli Bonardo, Nono Darsono, Syahrul Humaidi, Agung Imaduddin, Noni Surtiana Silalahi

Journal of Metals, Materials and Minerals

In this study, the influence of titanium oxide (TiO2) dopants and varying calcination processes on the thermoelectric properties of CuCrO2 was systematically explored. It was emphasized that these factors were not only affecting dislocation density but also exerting a profound influence on thermoelectric performance through the modulation of Seebeck coefficient and resistivity. The findings highlighted CrT-2, which incorporated TiO2 and underwent a two-time calcination process, as the top-performing sample in terms of power factor values, underscoring the significance of TiO2 as a dopant for enhancing thermoelectric efficiency. Conversely, Cr-4, exposed to four calcination cycles, exhibited slightly lower power factor values …

Electrical And Water Resistance Properties Of Conductive Paste Based On Gold/Silver Composites, Sutthipoj Wongrerkdee, Supab Choopun, Pichitchai Pimpang

Journal of Metals, Materials and Minerals

This study aimed to investigate the effects of a corrosive environment on both the electrical and the water resistance properties of conductive paste based on gold/silver composites. The conductive paste was prepared by incorporating silver and gold powders, polyvinyl acetate, polyvinyl chloride as adhesive components, and methyl isobutyl ketone as a diluent. The gold/silver composite powder was prepared with different mass ratios of gold and silver. The paste was coated on a substrate and heated at 80℃ to form the conductive paste film. Characterizations of conductive paste were performed by using FT-IR spectroscopy, electrometry, cyclic voltammetry, and contact angle measurements. …

Molybdenum Disulfide-Zirconium Dioxide Composite With Enhance Supercapacitance Performance, Razan Nadhim Shaker, Sami Mohammed, Yousra Ali Abdulsayed

Journal of Metals, Materials and Minerals

As a supercapacitor active material, molybdenum disulfide (MoS2) layer offers good conductivity, large surface area, and electrochemical stability. In practice, however, its capacitance is low in comparison to other materials. This work synthesized MoS2-zirconium dioxide (ZrO2) composite in a simple, high-throughput way to test it as a supercapacitor active layer. During the tests, the composite shows a gravimetric capacitance of 500.0 F⸳g-1, while MoS2 and ZrO2 have capacitances of 265.12 and 152.43, respectively. The increase in capacitance of composite stems from the synergistic effect between ZrO2's pseudocapacitor behavior and MoS2's electric double layer capacitance (EDLC). Moreover, the composite has a …

Modeling Of Quad-Station Module Cluster Tools Using Petri Nets, Aung Nay

Theses

The semiconductor industry is highly competitive, and with the recent chip shortage, the throughput of wafers has become more important than ever. One of the tools that the industry has deployed is to use of quad-station modules instead of the traditional single-station modules that allow for higher throughput and better wafer consistency by processing multiple wafers at the same time and distributing work. The industry trend is to use multiple transfer chamber robots to stack the quad-station modules in a series, particularly for etch products. In this work, the quad-station cluster tool wafer movement is modeled by using Petri net …

Carbon-Al Interface Effect On The Performance Of Ionic Liquid-Based Supercapacitor At 3 V And 65 OC, Zhen-Zhen Ye, Shu-Ting Zhang, Xin-Qi Chen, Jin Wang, Ying Jin, Chao-Jie Cui, Lei Zhang, Lu-Ming Qian, Gang Zhang, Wei-Zhong Qian

Journal of Electrochemistry

Ionic liquid (IL) electrolyte-based supercapacitors (SCs) have advantages of high operating voltage window, high energy density and nonflammability, as compared to conventional acetonitrile-based organic electrolyte SCs, and are typically suitable for the large-scale energy storage in the era of carbon neutrality full of renewable, but unstable electricity. However, current efforts were concentrated on the study with coin-cell type of IL-SCs, and less has been reported on the pouch type of IL-SCs for a long cycling time yet. To fabricate a reliable SC for the life time test or for the accelerated aging test under high temperature, one should concern the …

Application Of Artificial Intelligence To Lithium-Ion Battery Research And Development, Zhen-Wei Zhu, Jing-Yi Qiu, Li Wang, Gao-Ping Cao, Xiang-Ming He, Jing Wang, Hao Zhang

Journal of Electrochemistry

Lithium-ion batteries (LIBs) have become one of the best solutions to the energy storage issue in modern society. However, the battery materials and device development are both complex, and involve multivariable problems. Traditional trial-and-error approach, which relies on researchers to conduct experiments, has encountered bottlenecks in the improvement of the battery performance. Artificial intelligence (AI) is the most potential technology to deal with this issue due to its powerful high-speed and capabilities of processing massive data. In particular, the capability of machine learning (ML) algorithms in assessing multidimensional data variables and discovering patterns in the sets are expected to assist …

Advances On Composite Cathodes For Lithium-Sulfur Batteries, Xi-Yao Li, Chang-Xin Zhao, Bo-Quan Li, Jia-Qi Huang, Qiang Zhang

Journal of Electrochemistry

Lithium-sulfur (Li-S) batteries are deemed as high-promising next-generation energy storage technique due to their ultrahigh theoretical energy density, where the sulfur cathodes with high specific capacity guarantee the energy density advantage and directly determine the battery performances. After decades of exploration, the most promising sulfur cathodes are sulfur/carbon composite (S/C) cathodes and sulfurized polyacrylonitrile (SPAN) cathodes. In this manuscript, recent advances on S/C and SPAN cathodes in Li-S batteries are comprehensively reviewed. The electrochemical reaction circumstances on S/C and SPAN cathodes are firstly introduced and compared to reveal the working mechanisms of the two types of Li-S batteries. The S/C …

Multi-Electron Reaction-Boosted High Energy Density Batteries: Material And System Innovation, Rui-Qi Guo, Feng Wu, Xin-Ran Wang, Ying Bai, Chuan Wu

Journal of Electrochemistry

The continuous development of the global energy structure transformation has put forward higher demands upon the development of batteries. The improvements of the energy density have become one of the important indicators and hot topic for novel secondary batteries. The energy density of existing lithium-ion battery has encountered a bottleneck due to the limitations of material and systems. Herein, this paper introduces the concept and development of multi-electron reaction materials over the past twenty years. Guided by the multi-electron reaction, light weight electrode and multi-ion effect, current development strategies and future trends of high-energy-density batteries are highlighted from the perspective …

Preparation Of Highly-Cyclized Sulfurized Polyacrylonitrile For Lithium-Sulfur Batteries, Xuan Ji, Jia-Yu Wang, An-Bang Wang, Wei-Kun Wang, Ming Yao, Ya-Qin Huang

Journal of Electrochemistry

Sulfurized polyacrylonitrile (SPAN) is regarded as an attractive cathode candidate of lithium-sulfur (Li-S) batteries for its non-dissolution mechanism and effective alleviation of polysulfides shuttling issue in Li-S batteries, displaying high utilization of cathode active material, outstanding cycle stability and structural stability. However, the relation between cyclization degree and cycle stability of SPAN is still unveiled. In this work, SPAN-C-V composites were synthesized by co-introduction of CuSO₄ and zinc n-ethyl-n-phenyldithiocarbamate (ZDB) in the co-heating of sulfur and polyacrylonitrile. The co-introduction of CuSO₄ and ZDB reduced the cyclization reaction onset temperature of PAN while increased the C—C/C=C within SPAN-C-V, thus …

Developing An In Vitro Validated 3d In Silico Internal Carotid Artery Sidewall Aneurysm Model, Hang Yi, Zifeng Yang, Mark Johnson, Luke Bramlage, Bryan Ludwig

Mechanical and Materials Engineering Faculty Publications

Introduction: Direct quantification of hemodynamic factors applied to a cerebral aneurysm (CA) remains inaccessible due to the lack of technologies to measure the flow field within an aneurysm precisely. This study aimed to develop an in vitro validated 3D in silico patient-specific internal carotid artery sidewall aneurysm (ICASA) model which can be used to investigate hemodynamic factors on the CA pathophysiology. Methods: The validated ICASA model was developed by quantifying and comparing the flow field using particle image velocimetry (PIV) measurements and computational fluid dynamics (CFD) simulations. Specifically, the flow field characteristics, i.e., blood flowrates, normalized velocity profiles, flow streamlines, …

Phase-Averaged, Frequency Dependence Of Jet Dynamics In A Scaled Up Vocal Fold Model With Full And Incomplete Closure, Nathaniel Wei, Abigail Haworth, Hunter Ringenberg, Michael Krane, Timothy Wei

Department of Mechanical and Materials Engineering: Faculty Publications

This study focuses on frequency dependence effects on glottal jet dynamics with a focus on the physiological condition in which the vocal folds do not fully close. Incomplete closure occurs naturally in children and adult females. But there are also pathological conditions that can be problematic. Experiments were conducted using a 10× scaled-up model in a free surface water tunnel. Two-dimensional vocal fold models with semicircular medial surfaces were stepper motor driven inside a square duct with constant opening and closing speeds. Cases with complete vocal fold closure and incomplete closure to only 15% of the maximum gap were examined. …

Sars-Cov-2 Detecting Rapid Metasurface-Based Sensor, Shobhit K. Patel, Jaymit Surve, Juveriya Parmar, Khaled Aliqab, Meshari Alsharari, Ammar Armghan

Department of Mechanical and Materials Engineering: Faculty Publications

We have proposed a novel approach to detect COVID-19 by detecting the ethyl butanoate which high volume ratio is present in the exhaled breath of a COVID-19 infected person. We have employed a refractive index sensor (RIS) with the help of a metasurface-based slotted T-shape perfect absorber that can detect ethyl butanoate present in exhaled breath of COVID-19 infected person with high sensitivity and in-process SARS-CoV-2. The optimized structure of the sensor is obtained by varying several structure parameters including structure length and thickness, slotted T-shape resonator length, width, and thickness. Sensor’s performance is evaluated based on numerous factors comprising …

Energy Dissipation In A Sand Damper Under Cyclic Loading, Ehab Sabi

Civil and Environmental Engineering Theses and Dissertations

Various seismic and wind engineering designs and retrofit strategies have been in development to meet structures' proper and safe operation during earthquake and wind excitation. One such method is the addition of fluid and particle dampers, such as sand dampers, in an effort to reduce excessive and dangerous displacements of structures. The present study implements the discrete element method (DEM) to assess the performance of a pressurized sand damper (PSD) and characterize the dissipated energy under cyclic loading. The idea of a PSD is to exploit the increase in shearing resistance of sand under external pressure and the associated ability …

Nanoscale Imaging Of Antiferromagnetic Domains In Epitaxial Films Of Cr2O3 Via Scanning Diamond Magnetic Probe Microscopy, Adam Erickson, Syed Qamar Abbas Shah, Ather Mahmood, Ilja Fescenko, Christian H. Binek, Adbelghani Laraoui

Department of Mechanical and Materials Engineering: Faculty Publications

We report direct imaging of boundary magnetization associated with antiferromagnetic domains in magnetoelectric epitaxial Cr₂O₃ thin films using diamond nitrogen vacancy microscopy. We found a correlation between magnetic domain size and structural grain size which we associate with the domain formation process. We performed field cooling, i.e., cooling from above to below the Néel temperature in the presence of a magnetic field, which resulted in the selection of one of the two otherwise degenerate 180° domains. Lifting of such a degeneracy is achievable with a magnetic field alone due to the Zeeman energy of a weak …

Potential Of Mechanical Grain Dryers In Addressing Exposure Of Rice Farmers To Weather Risks, Hernaiz Malanon, Zenaida Sumalde

The Philippine Agricultural Scientist

Weather risks brought by prolonged rainfall and cloudy days hamper grain drying operations in the Philippines as majority still employ the sun drying method, which limits the opportunity of rice farmers to earn a higher income. While mechanical dryers are considered an important adaptation mechanism to address weather risks, more research needs to be done on their benefits and their disadvantages. This study adapted the Inter-governmental Panel on Climate Change (IPCC) concept which equates hazard, exposure, and vulnerability to quantify risk. Hazard was assessed in terms of the probability of four straight rainy- or cloudy-day occurrences based on a 30-year …

Sulfonated Styrene Grafted Sebs/Abs Made By Additive Manufacturing For Ion Exchange Applications, Avianna Elaine Gallegos

Open Access Theses & Dissertations

An interpenetrating polymer network (IPN) for cation exchange applications was synthesized from a blend of styrene-ethylene/butylene-styrene (SEBS) and acrylonitrile butadiene styrene (ABS), which was 3D printed, grafted with crosslinked polystyrene (PS), and sulfonated. A method for styrene grafting was applied to reduce the damage to polymer phases caused by the sulfonation reaction. Styrene and divinylbenzene monomers were introduced to the IPN and induced with heat treatment to polymerize in situ. The graft copolymerization reaction was enhanced with varying quantities of benzoyl peroxide as a chemical initiator. The samples were subsequently sulfonated with chlorosulfonic acid in dichloroethane and functionalized for ion …

A Comparative Evaluation Of Oxidation And Combustion Phenomena In Ti-6al-4v Exposed To Earth Re-Entry And Arc-Jet Test Environments, Arlene Smith

Open Access Theses & Dissertations

The Ti-6Al-4V alloy is widely used in aerospace applications for its beneficial combination of properties. However, this alloy has high solubility for oxygen and thus a high reactivity. Recovered data contained within the Columbia artifacts suggests that this alloy underwent an accelerated degradation and combustion reaction when exposed to the high enthalpy, low-pressure surroundings experienced during reentry into Earth's atmosphere. Arc-jet testing has provided a simulated aerothermodynamic heating environment to mimic what the spacecraft endured. When the effect of thermal alteration on this alpha-beta phase alloy was investigated during previous studies, optical metallography and microhardness tests revealed inconsistencies between samples …

Experimental Tests And Numerical Study Of Trajectories Of Different Types Of Dropped Objects, Yi Li

LSU New Orleans Theses and Dissertations

In marine and offshore engineering, dropped objects, such as drill pipes, anchor chains, containers and some small parts, can accidentally fall into the water from ships or offshore platforms, causing casualties on deck or damage to underwater equipment. Damaged equipment can further harm the environment, such as oil spills from damaged wellheads. Therefore, for safe engineering and environmental protection reasons, we need to develop methods and tools that can predict the trajectory of dropped objects.

In this dissertation, we first study containers dropped from ships. More and more containers are falling into the sea due to bad weather. Containers lost …

Nano-Engineered Soft Magnets: Potential Application In Water Treatment, Hyperthermia And Molecular (Organic) Magnets, Yohannes Weldemariam Getahun

Open Access Theses & Dissertations

Scrutinizing the remarkable and tunable properties of magnetic materials at a nanoscale size "There's Plenty of Room at the Bottom..." Richard Feynman, this study attempts to find sustainable solutions to some of the deteriorating environmental, health, and energy problems the world is encountering. Due to their simple preparation, surface adaptability, and tunable magnetic and optical properties, magnetic nanoparticles have been extensively investigated in water treatment, cancer therapy, data storage, and more. However, relying on non-reusable and chemical-based treatment agents in water, complex and costly cancer treatment procedures and molecular magnets that operate far below room temperature limited those attempts from …

The Qualification Of Sealability And Creep Relaxation Of Additively Manufactured Zytel Gaskets For Pem Fuel Cells, Robert Lazarin

Open Access Theses & Dissertations

The purpose of this thesis is to study the feasibility of low-cost additive manufacturing of gaskets for proton exchange membrane fuel cells exposed to extreme temperature conditions ranging from -55°C to 100°C. With the growing popularity and decreasing costs of additive manufacturing technologies, specifically Material Extrusion (ME), research is being conducted to determine the feasibility of ME components. Thermally cycled PEMFCs may exhibit accelerated gasket deterioration, therefore, the mechanical stability of material extruded gaskets following a harsh thermal cycle must be assessed. The feasibility of the material extruded gaskets will be proven by manufacturing optimization and mechanical testing. The target …

Novel Interlaminar Reinforcement To Enhance The Impact Damage Resistance Of Carbon Fiber-Reinforced Polymer Matrix Composites, Daisy Haidee Mariscal

Open Access Theses & Dissertations

Aerospace, aircraft, marine, and automobile applications are increasingly using composite materials for lighter, higher stiffness, and strength properties. Despite these advantages, composite materials have one major disadvantage. The through-thickness properties are extremely weak when subjected to impact damage. When a composite material is subjected to a low-velocity impact, there is hardly any visible damage on the surface compromising the composite material internally without any external notice. Internal damage may be delamination, which is the most common, matrix cracking, and fiber breakage. A composite material is made up of layers of fiber. The interlaminar region is located in between these layers. …

Fabrication, Microstructure And Mechanical Characterization Of Crvnbtaw High Entropy Alloy Coatings Using Magnetron Sputtering, Jorge Quezada

Open Access Theses & Dissertations

In this project a CrVNbTaW high entropy alloy was evaluated. The samples were made using radio frequency magnetron sputtering and were made under similar conditions. The deposition parameters were explored to find the ideal deposition process. The process included a pressure from 0.1-2mTorr, 600C, 1 hour duration, at 100W power to guns, and constant argon flow. The samples were fabricated under similar parameters using silicon steel and sapphire substrates. The samples were analyzed and characterized using X-ray diffraction, scanning electron microscopy, atomic force microscopy, nanoindentation and corrosion testing. Based on these results we were able to get a better understanding …

Magnetic Structures Of Sawtooth Olivines Mn2six 4 (X = S, Se) Determined Through Neutron Powder Diffraction, Melaku Sisay Tafere

Open Access Theses & Dissertations

In olivine chalcogenide Mn2SiX 4 (X = S, Se) compounds, the Mn lattice produces a sawtooth, which is of critical significance in magnetism due to the potential for manifesting at bands in the magnon spectrum, a crucial component in magnonics. The compounds Mn2SiS4 and Mn2SiSe4 in Mn2SiX 4 family undergo antiferromagnetic phase transitions at T â?? 85 K and â?? 66 K, respectively, as determined from the specific heat, Cp(T). The average and local crystal structuresare determined using synchrotron X-ray, neutron diffraction, and X-ray total scattering data followed by Rietveld and pair distribution function (PDF) analysis. It is found from …