Materials Science and Engineering Commons^™

Evolution Of Mg Az31 Twin Activation With Strain: A Machine Learning Study, Andrew D. Orme

Undergraduate Honors Theses

Machine learning is being adopted in various areas of materials science to both create predictive models and to uncover correlations which reveal underlying physics. However, these two aims are often at odds with each other since the resultant predictive models generally become so complex that they can essentially be described as a black box, making them difficult to understand. In this study, complex relationships between microstructure and twin formation in AZ31 magnesium are investigated as a function of increasing strain. Supervised machine learning is employed, in the form of J-48 decision trees. In one approach, strain is incorporated as an …

Dynamic Behavior Of Materials, Jeremy Floyd, Andrew Minor

Research Horizons Day Posters

No abstract provided.

Hawai'i Wildlife Fund V. County Of Maui, Lowell J. Chandler

Public Land & Resources Law Review

In Hawai’i Wildlife Fund v. County of Maui, the Ninth Circuit held that the plain language of the Clean Water Act provides jurisdiction over indirect discharges of pollutants from a point source into groundwater that is shown to be connected to navigable waters. The court found that studies confirmed pollutants entering the Pacific Ocean were fairly traceable to the County of Maui’s sewage disposal wells. In affirming the district court’s ruling, the Ninth Circuit held that Maui County violated the Clean Water Act by discharging pollutants into a navigable water without the required permit. The court also concluded the …

The Application Of The Peleg Model In Order To Obtain Completely Soluble Materials For Food Product Packaging, Roxana Puscaselu (Gheorghita), Sonia Amariei

Journal of Applied Packaging Research

The aim of this study was to create a completely hydrosoluble edible films based on biopolymers that can be used as packaging material for powdered foods.10 edible films were obtained from various mixtures of hydrocolloids (agar, starch, sodium alginate) plasticized with glycerol and water. To assess their solubility, it was used the Peleg model which confirmed that increasing the temperature of the hydration medium, increases the water absorption rate. The sample obtained from agar and starch was less hydrophilic than sample with a high amount of sodium alginate, which was completely soluble after 3 minutes maintenance in 20° water. To …

From Flasks To Applications: Design And Optimization Of Giant Quantum Dots Using Traditional And Automated Synthetic Methods, Christina J. Hanson

Nanoscience and Microsystems ETDs

Semiconducting nanocrystals, also known as quantum dots (QDs), that emit light with near-unity quantum yield and are extremely photostable are attractive options as down-conversion and direct electricity-to-light materials for a variety of applications including solid-state lighting, display technologies, bio-imaging and optical tracking. Standard QDs with a core/thin shell structure display fluorescence intermittency (blinking) and photobleaching when exposed to prolonged room temperature excitation for single dot measurements, as well as significant reabsorption and energy transfer when densely packed into polymers or at high solution concentrations.

We have developed thick shell “giant” QDs (gQDs), ultra-stable photon sources both at the ensemble and …

Nanostructured Materials Derived From Metal-Organic Frameworks For Energy And Environmental Applications, Zhiqiang Xie

LSU Doctoral Dissertations

Nowadays, energy and environmental issues have become the top priority among a series of global issues. Fossil fuels as the dominant source are depleted fast and usually lead to some environmental problems. Heavy metal pollution has posed a severe threat to environment and public health. Metal-organic frameworks (MOFs), as a very promising category of porous materials, have attracted more and more interest in research communities due to their extremely high surface areas, diverse nanostructures and unique properties. To meet the ever-increasing energy demand and tackle the heavy metal pollution in water, MOFs can function as ideal templates to prepare various …

Scalable Patterning Using Laser-Induced Shock Waves, Saidjafarzoda Ilhom, Khomidkhodza Kholikov, Peizhen Li, Claire Ottman, Dylan Sanford, Zachary Thomas, Omer San, Haluk E. Karaca, Ali O. Er

Mechanical Engineering Faculty Publications

An advanced direct imprinting method with low cost, quick, and minimal environmental impact to create a thermally controllable surface pattern using the laser pulses is reported. Patterned microindents were generated on Ni₅₀Ti₅₀ shape memory alloys and aluminum using an Nd: YAG laser operating at 1064 nm combined with a suitable transparent overlay, a sacrificial layer of graphite, and copper grid. Laser pulses at different energy densities, which generate pressure pulses up to a few GPa on the surface, were focused through the confinement medium, ablating the copper grid to create plasma and transferring the grid pattern onto …

Review Of Challenges And Advances In Modification Of Food Package Headspace Gases, Ziynet Boz, Bruce A. Welt, Jeffrey K. Brecht, William Pelletier, Eric Mclamore, Gregory A. Kiker, Jason E. Butler

Journal of Applied Packaging Research

Modified Atmosphere Packaging (MAP) has been widely used as an effective way to preserve foods. Fresh produce, meat and meat products, seafood, and dairy products can benefit from modified gaseous atmospheres, which are usually achieved by reducing oxygen and increasing carbon dioxide concentrations, within limits, defined by product tolerances. MAP of fresh produce is particularly challenging because products are living and respiring. Respiration rates depend on several factors including temperature, oxygen, and carbon dioxide concentrations. Balancing package permeation with respiration is challenging, often due to limited selection of practical packaging materials. Failing to remain within tolerance limits of products leads …

Waste Management By Waste: Removal Of Acid Dyes From Wastewaters Of Textile Coloration Using Fish Scales, S M Fijul Kabir

LSU Master's Theses

Removal of hazardous acid dyes by economical process using low-cost bio-sorbents from wool industry wastewaters is of a pressing need, since it causes skin and respiratory diseases and disrupts other environmental components. Fish scales (FS), a by-product of fish industry, a type of solid waste, are usually discarded carelessly resulting in pungent odor and environmental burden. In this research, the FS of black drum (Pogonias cromis) were used for the removal of acid dyes (acid red 1 (AR1), acid blue 45 (AB45) and acid yellow 127 (AY126)) from wool industry wastewaters by absorption process with a view to …

Efficiency Of Solid Inclusion Removal From The Steel Melt By Ceramic Foam Filter: Design And Experimental Validation, Soumava Chakraborty, Ronald J. O'Malley, Laura Bartlett, Mingzhi Xu

Materials Science and Engineering Faculty Research & Creative Works

An investigation was performed to measure the efficiency of solid alumina inclusion removal by filtration during casting. A mold design was developed using modeling software to produce two castings that fill simultaneously, one with a filter and the other without a filter. The design avoided vortex formation and thus air entrainment, which helped to avoid reoxidation inside the mold cavity. Samples from these castings were analyzed utilizing an SEM/EDS system with automated feature analysis (AFA) to measure the efficiency of inclusion removal using a 20 ppi zirconia foam filter. This study also documents the occurrence of inclusion flotation and agglomeration …

Characterization Of Magnetic Thin Films Using The Magneto Optic Kerr Effect, Nicholas J. Savino

Student Scholar Showcase

Understanding magnetic properties of materials allows for advances in applications such as data storage. The Magneto-Optic Kerr Effect (MOKE) displays the reflective response a magnetic material has to a magnetic field. When polarized light reflects off of a magnetic material, the polarization orientation can change. The application of an external magnetic field can affect how much this polarization changes in a non-linear manner. Hysteresis loops are created when examining the relationship between intensity of the reflected light to the applied magnetic field provide information about magnetic properties of that material, such as the coercive field and field retention. Preliminary measurements …

Effect Of Fe Substitution On Structural, Magnetic And Electron-Transport Properties Of Half-Metallic Co2tisi, Juliana Herran, Parashu Kharel, Pavel Lukashev

Research in the Capitol

In recent years, research on magnetic materials has been one of the most technologically appealing developments in materials science. Among other applications, magnetic materials are essential components of data storage and information processing in computer hardware elements, such as hard drives and random access memories. Here, we present a theoretical study of structural, magnetic and electronic properties of ferrimagnetic Co₂Ti_1−xFe_xSi (x = 0, 0.25, 0.5), using density functional calculations. We show that the magnetic moment of Co₂Ti_1−xFe_xSi increases when Ti is substituted with Fe, consistent with experimental findings. …

Computational Discovery Of Energetic Polynitrogen Compounds At High Pressure, Brad A. Steele

USF Tampa Graduate Theses and Dissertations

High-nitrogen-content energetic compounds containing multiple N-N bonds are an attractive alternative towards developing new generation of environmentally friendly, and more powerful energetic materials. High-N content translates into much higher heat of formation resulting in much larger energy output, detonation pressure and velocity upon conversion to large amounts of non-toxic, strongly bonded N2 gas. This thesis describes recent advances in the computational discovery of group-I alkali and hydrogen polynitrogen materials at high pressures using powerful first-principles evolutionary crystal structure prediction methods. This is highlighted by the discovery of a new family of materials that consist of long-sought after all-nitrogen N􀀀 5 …

Design Optimization Of Polymer Heat Exchanger For Automated Household-Scale Solar Water Pasteurizer, David C. Denkenberger, Joshua M. Pearce

Department of Materials Science and Engineering Publications

A promising approach to reducing the >870,000 deaths/year globally from unsafe water is flow-through solar water pasteurization systems (SWPs). Unfortunately, demonstrated systems have high capital costs, which limits access for the poor. The most expensive component of such systems is the heat exchanger (HX). Thus, this study focuses on cost optimization of HX designs for flow-through SWPs using high-effectiveness polymer microchannel HXs. The theoretical foundation for the cost optimization of a polymer microchannel HX is provided, and outputs are plotted in order to provide guidelines for designers to perform HX optimizations. These plots are used in two case studies: (1) …

A Laboratory Kit For Multimeter Design, Seth Percy, Joshua Perry

Thinking Matters Symposium Archive

The multimeter is an important electrical tool and is a combination of many individual instruments. In practice, common multimeter designs are digital and measure voltage, current, resistance, capacitance, etc., using a single set of probes. Before the digital age, the world relied on analog displays. Some argue that analog displays are outdated technology. However, this overlooks one of the most important characteristics provided by the analog display, which is its ability to provide an instantaneous visual perception. Analog displays are currently used for many applications in aviation and automobiles, demonstrating their continuing usefulness in the field. In the multimeter, the …

High Fidelity Kinetic Model For Flotation: Applications To Rare Earth Elements And Copper/Molybdenum Separations, Richard Ladouceur

Graduate Theses & Non-Theses

A high-fidelity kinetic model was developed to identify and elucidate the effects of varying principle froth flotation parameters on the sub-processes that occur within and between the flotation zones. Whereas traditional models fail to adequately address froth recovery and recovery by entrainment, the high-fidelity model defines these phenomena based on an improved understanding of the pulp/froth interface. Solution chemistry considerations that govern rare earth mineral separation by flotation were identified, characterized, and optimized. Application of novel surfactants such H205 and salicylhydroxamic acid (collectors) and dimethyl glycol monobutyl ether (depressant) was evaluated to define optimal flotation conditions. The effect of pressure …

An Evaluation Of Induction Heating In Healthcare Food Industry, Barrett Alexander Hampton

Masters Theses & Specialist Projects

This thesis addresses the problem healthcare facilities are having in maintaining proper food temperatures while transporting meals to patients after food has left the kitchen area. Induction heat has been a known method for generating heat for many years. The commercial food industry currently uses this technology, which is beginning to appear in the residential sector as well because of developments made by manufacturers. This study focuses on the top commercial brand models of induction heaters and the supporting materials currently used to create heat sources to maintain food temperatures in hospitals and long term care facilities.

The research in …

Small-Signal-Stability Enhancement Using A Power-System Stabilizer Based On The Cuckoo-Search Algorithm Against Contingency N-1 In The Sulselrabar 150-Kv System, Muhammad Ruswandi Djalal, Muhammad Yusuf Yunus, Herlambang Setiadi, Awan Uji Krismanto

Makara Journal of Technology

Small-signal stability is one of the main factors limiting power transmission in conventional power systems. This concern is primarily handled by adding damper windings of a synchronous generator and power-system stabilizer (PSS). However, due to the impact of the N-1 contingency, damper windings and a conventional PSS are insufficient to overcome this problem. Proper placement and design of the PSS are crucial for improving stability. One approach to optimizing the placement and tuning of the PSS is to use an artificial-intelligence method. Here, the cuckoo-search algorithm (CSA) is proposed to optimize the PSS tuning and placement. Based on simulation, it …

Isolation And Molecular Weight Characterization Of Tetragonula Laeviceps Honey Protein, Muhamad Sahlan, Nurul Azizah, Kazuaki Hakamada, Keiichi Noguchi, Masafumi Yohda

Makara Journal of Technology

The concentration of protein in honey is lower than polysaccharide. However, recently the honey’s protein is intensively studied and it showed that protein also have several biological activities such as antibacterial activity. The purpose of this research is to isolate and characterize Tetragonula laeviceps honey protein by determining the molecular weight. Honey protein of Trigona laeviceps was isolated using ultra-filtration with the membrane’s size of 30 kDa, then concentrated using tube membrane size 10 kDa. Molecular weight was analyzed by SDS PAGE. From the analysis, there was major protein band in honey produced by Tetragona laeviceps identified. The produced molecular …

Prerequisites For Public Acceptance Of Waste-To-Energy Plants: Evidence From Germany And Indonesia, Uwe Lahl, Barbara Zeschmar-Lahl

Makara Journal of Technology

Construction of waste incinerators often encounters resistance from the public. The minimum requirements for the ac- ceptance of these installations include modern air pollution control (APC) technology and safe disposal of residues. Confidence in the statements of government and government agencies as well as on those who support is an important point of acceptance. Independent scientific bodies such as universities can help to make this happen. In the case of the installation of waste into energy (WtE), such scientific support can be the measurement of emissions and their evalua- tion. Many products that enter the waste stream contain heavy metals, …

Hybrid Brain-Computer Interface: A Novel Method On The Integration Of Eeg And Semg Signal For Active Prosthetic Control, Reza Darmakusuma, Ary Setijadi Prihatmanto, Adi Indrayanto, Tati Latifah Mengko

Makara Journal of Technology

This paper describes a novel method for controlling active prosthetics by integrating surface electromyography (sEMG) and electroencephalograph signals to improve its intuitiveness. This paper also compares the new method (RTA-2) with other existing methods (AND and OR) for controlling active prosthetics. Based on analysis, RTA-2 features higher true positive rate (TPR) and balanced accuracy (BA) than AND method. On the other hand, the new method (RTA-2) yields lower false detection rate (FPR) than OR method. Analysis also shows that RTA-2 possesses equal TPR, FPR, and BA with the detection of movement intention using sEMG-based system. Although the RTA-2 method shows …

Non-Newtonian Fabric-Fluid Composites: Fabrication, Characterization And Testing For Anti-Ballistics Applications, Hayley M. Weir

All Theses

This thesis aims to characterize non-Newtonian suspensions for anti-ballistics applications. This involves characterizing the rheological behavior of each suspension. It also includes characterizing the interactions of the suspensions with several types of fabrics with known antiballistics properties. The study also tests the armor composites under ballistics stresses by firing on them with standardized military weaponry. This data is then compiled to determine which, if any, of the fabrics and suspensions are ultimately suitable for anti-ballistics uses.

Evaluation Of Metallurgical And Mechanical Properties Of Alsi10mg Produced By Selective Laser Melting, Luke J. Suttey

Graduate Theses & Non-Theses

Selective laser melting (SLM) additive manufacturing (AM) of metal powders has long been a focus in the study of AM due to the possibility of weight reduction, complex shape formation, and production cost savings. Although applicable to a variety of metals SLM AM of the AlSi10Mg alloy was studied in an attempt to characterize the effect of processing parameter and build angle variation on the final microstructural, fractographic, and mechanical properties of parts produced without any thermal post-processing techniques. Research was conducted on five build angles (0°, 30°, 45°, 60°, and 90°), and three Global Energy Densities (GED) (37.15, 45.39, …

New Method Of Nickel Oxide As Hole Transport Layer And Characteristics Of Nickel Oxide Based Perovskite Solar Cell, Loi Nguyen

Electrical & Computer Engineering Theses & Dissertations

For perovskite solar cells, poly (2,3-dihydrothieno-1, 4-dioxin)-poly (styrenesulfonate) (PEDOT:PSS) is a common hole transport layer. However, PEDOT:PSS has a lot of drawbacks, such as irregular quality from distributors, poor electron blocker, and hygroscopic nature. On the other hand, NiOx has been reported that it can provide good stability and carrier mobility. From literature, NiOx was used to replace PEDOT:PSS as a hole transport layer with positive results since it is transparent as a thin film and also possesses compatible work function in perovskite solar cell bandgap alignment. In depositing NiOx as a thin film, many approaches have been developed. However, …

Structural And Photoluminescence Properties Of Zno Thin Films Deposited By Ultrasonic Spray Pyrolysis, Iwan Sugihartono, Erfan Handoko, Vivi Fauzia, Artoto Arkundato, Lara Permata Sari

Makara Journal of Technology

Zinc oxide (ZnO) thin films on a silicon (Si) (111) substrate were grown herein using ultrasonic spray pyrolysis at 450 °C with different Zn concentrations. The ZnO thin films had X-ray diffraction patterns of a polycrystalline hexagonal wurtzite structure. The (002) and (101) peak intensities changed under different Zn concentrations. Furthermore, according to Scherer's and Stokes–Wilson equations, the crystallite size and the internal strain of the ZnO thin films in the (002) and (101) peaks changed with the Zn concentration. Optically, the photoluminescence spectra indicated that the ratio of the UV/GB emission of the ZnO thin films was the highest …

Swelling As A Stabilizing Mechanism During Ion Bombardment Of Thin Films: An Analytical And Numerical Study, Jennifer M. Swenson

Mathematics Theses and Dissertations

Irradiation of semiconductor surfaces often leads to the spontaneous formation of rippled structures at certain irradiation angles. However, at high enough energies, these structures are observed to vanish for all angles, despite the absence of any identified, universally-stabilizing physical mechanisms in operation. Here, we examine the effect on pattern formation of radiation-induced swelling, which has been excluded from prior treatments of stress in irradiated films. After developing a suitable continuum model, we perform a linear stability analysis to determine its effect on stability. Under appropriate simplifying assumptions, we find swelling indeed to be stabilizing at wavenumbers typical of experimental observations. …

An Exploratory Study Of Sukuk Utilisation For Transportation Infrastructure Development In Indonesia, Fiona Lamari, Ayomi Dita Rarasati, Meilia Evita

Makara Journal of Technology

Investment in infrastructure is one of the principal drivers of the growth of the economy. For that reason, the Indonesian government has proposed an investment budget in the railway and sea and air transport sectors over the next 10 years. In order to overcome the burden of direct outflows and for the future, a study was conducted to lay down the framework of Shariah-compliant payments for the development of infrastructure in Indonesia in the transport sector. This paper aims to explore the opportunity and implementation of sukuk utilisation to develop transportation infrastructure. Secondary data study and interviews were selected for …

Characterization Of Process Induced Defects In Laser Powder Bed Fusion Processed Alsi10mg Alloy, Edward Stugelmayer

Graduate Theses & Non-Theses

Additive manufacturing using laser powder bed fusion (AM-LPBF) methods have recently experienced rapid growth and development, having the potential to replace manufacturing by plastic deformation, precision machining, or casting. AM offers advantages such as the freedom to design highly complex geometries, time and cost savings through material usage efficiency and shortened production cycles, and the potential for improved mechanical properties. Process induced defects, however, result in degradation and scattering of mechanical properties and hinder the widespread adoption of AM-LPBF in industry. This investigation focuses on the effects of varying energy density and build orientation on the evolution of process induced …

Novel Hybrid Perovskite Composites And Microstructures: Synthesis And Characterization, John P. Murphy

Graduate Theses & Non-Theses

The water-energy nexus has been described as one of the great problems of our time. In an ever-growing society the demand for resources such as water and electricity often dictate the magnitude and direction of growth of society. Efficient generation of electricity, with minimal socioeconomic pushback, is paramount in the stable growth of our society. Solar energy harvesting is a strong candidate for the efficient generation of electrical energy with increasingly minimal resource use in fabrication. As manufacturing processes improve and novel materials are discovered/optimized, solar energy harvesting becomes a more economically viable means of energy generation. Hybrid perovskites (HPs) …

Investigations Of Solid-State Sintering Behavior Of Binary Refractory Metal Oxide Systems, Maureen Chorney

Graduate Theses & Non-Theses

Refractory metals are commonly alloyed for improved corrosion resistance, thermal stability, and strength. In service, these alloys form highly stable oxides under mildly oxidizing conditions at relatively low temperatures. In order to recycle these materials, high temperature electrochemical processing is required to reduce the refractory metal oxides. To abet experimental evaluation of the electrochemical reduction process under development at the Idaho National Laboratory, binary mixtures of selected refractory metal oxide powders were sintered to produce cathode pellets, which could be suspended in the molten salt electrolyte during reduction experiments. Preparatory literature review revealed a paucity of published information relative to …