Materials Science and Engineering Commons^™

Metal Complexes Of Redox Active Ligands, Alexandra Chaparro, Parker Keller

Chemistry & Biochemistry Student Scholarship

Alexandra Chaparro ’22, Major: Biochemistry

Parker Keller ’24, Major: Chemistry

Mentor: Dr. Maria Carroll, Chemistry and Biochemistry

Our research focuses on synthesizing and studying the properties of metal complexes that contain redox active ligands. Ligands are molecules or ions that can bind to a metal ion, and this particular class of ligands is interesting because they can either accept or lose electrons. We synthesized zinc complexes, in order to measure the reduction potentials of the ligands, which provide information about the ease with which they accept electrons. We then synthesized iron complexes and determined their structures. These complexes are potentially …

Lattice Dynamics, Mechanical Properties, Electronic Structure And Magnetic Properties Of Equiatomic Quaternary Heusler Alloys Crticoz (Z = Al, Si) Using First Principles Calculations, Eesha Andharia, Hind Alqurashi, Bothina Hamad

Physics Faculty Publications and Presentations

First principles calculations are performed to investigate the thermodynamical stability, dynamical, mechanical, electronic and magnetic properties of CrTiCoZ (Z = Al/Si) novel quaternary Heusler alloys. A Y-type III atomic configuration is found to be the most stable structure for both compounds. The lattice constant values obtained using GGA-PBE approach are 5.9368 Å and 5.7853 Å for CrTiCoAl and CrTiCoSi, respectively. Using the value of elastic moduli for both the compounds, the computed Pugh’s ratio value is 2.5 and 2.7 for CrTiCoAl and CrTiCoSi, respectively, which is higher than 1.75, indicating both the compounds are ductile in nature. The melting temperatures …

Detection And Identification Of Disturbances By Spectral Analysis Of Structure-Borne Noise During The Production Of A Sealing Seam, Felix Kruppa, Lars Meisenbach, Berend Oberdorfer Dr.-Ing., Bernd Wilke Prof. Dr.-Ing.

Journal of Applied Packaging Research

When sealing, disturbances or errors can occur that impair the quality of the sealing seam and, in the worst case, lead to leaks. It is therefore important to identify and eliminate defective packages during production and to minimize the elimination by readjusting machine parameters. The aim of this article is the clear identification of seam quality problems on a vertical forming, filling and sealing machine SVE2520 by evaluating process parameters during the manufacturing process. For this purpose, the structure-borne noise is measured for each seal in order to identify not-usual curves. These not-usual curves are related to different disturbances or …

Simplified Synthesis Of Conjugated Polymers Enabled Via 1,4-Dihydropyrrolo[3,2-B]Pyrrole, Kenneth-John Jack Bell

Master of Science in Chemical Sciences Theses

Conjugated polymers have attracted significant attention as the active layer material in organic electronics, such as organic photovoltaics and light-emitting diodes, partly due to the ability to influence a broad range of properties through structural design motifs. However, high performance conjugated polymers suffer from numerous synthetic steps, generation of toxic waste, and harsh reaction conditions all of which impart additional costs that inhibit their widespread utilization. Therefore, an emphasis on reducing synthetic complexity and utilizing abundant, commercially available starting materials is needed for organic electronics to reach their full potential. Dihydropyrrolo[3,2-b]pyrrole (H₂DPP) chromophores offer a simple one-pot synthesis …

Development Of Synergistic Electrochemical Catalysis For Advancing Co2 Utilization, Naohiro Fujinuma

Theses and Dissertations

Electrochemical CO2 utilization is an attractive process for realizing carbon-neutral chemical production due to its electricity-driven ambient conditions, compatibility with renewable energy, and diversified products. This study aims to address unmet challenges hindering the wide adaptation of the process: (I) the absence of a highly selective and scalable catalyst for CO2 reduction reaction (CO2RR), (II) the large number of laborious experiments needed to optimize electrochemical materials/devices, and (III) the lack of an effective scheme for upgrading CO2-derived products. First, a bio-mimicking multi-component catalyst is explored, leading to the discovery of a highly selective Co-pyridine-derived catalyst for CO2RR into CO. The …

Optimizing The Self-Healing Efficiency Of Hydrogel Encapsulated Bacteria In Concrete, Ricardo Hungria

LSU Master's Theses

Calcium carbonate precipitation through microbial means is a promising pathway for concrete self-healing technologies, mainly for its microcrack sealing attributes. The main goal of this project was to study and optimize the crack healing efficiency of hydrogel encapsulated bacteria in concrete. To achieve this purpose, Bacillus pseudiformus was implemented as the bacteria strain at a concentration of 10⁸ cells/ml. This bacterium strain along with yeast extract was combined along with three different mineral precursors corresponding to magnesium acetate, calcium lactate, and sodium lactate. All these three precursors were evaluated at two concentrations (67.76 mM/l and 75 mM/l). For each …

Detection Of Trace Heavy Metals In Water: Development Of Electrochemical Sensors, Quang Lam, Joel Mututeke

Symposium of Student Scholars

The presence of heavy metals in our ecosystem poses significant ecological and physiological consequences. As a result, numerous techniques are developed for the detection of contaminants in aqueous solutions. However, early and trace detection of such contaminants still remains a challenge. Amongst many techniques, electrochemistry driven sensors have shown promise due to their possibility of miniaturization and low-cost. Our research investigates the use of electrically conducting polymer and atomically thin carbon materials as electrodes towards the development of electrochemical sensor. Nanocomposite electrode films have been synthesized and fabricated using in-situ polymerization technique and the relationship between number of cycles of …

Novel Thermal Coating For High-Speed Airplanes, Abinash Satapathy, Lakshay Battu, Liam Watson, Nazanin Rajabi

Symposium of Student Scholars

In comparison to various other materials, Carbon Fiber, specifically Carbon Fiber Reinforced Polymers (CFRP), is pre-eminent amongst other materials for use on aeronautical systems. Due to its high specific strength (strength-to-weight ratio), CFRP is prominent for carrying heavy loads while maintaining a lightweight build. However, when influenced by heat resulting from air resistance, CFRP is known to undergo serious degradation that would significantly decrease the effectiveness of the polymers. To prevent this degradation and maintain the strength of the CFRP, thermal protective layers (TPLs) are designed to shield the CFRP from heat exposure. This research is focused on the examination …

Prospects For Using Metal-Polymer Composite Structures In The Gear Manufacturing, Umid Mamasobirov, Shoraxmat Shoobidov, A F. Husanboyev

Technical science and innovation

In this paper, some thermoplastic polymer composites and filler composites for the production of metal-polymer gear transmissions are presented. Efforts have been made to expand the raw material base and identify ways to increase the durability of gears through technological and design measures.

Effect Of Micro-Structural Dispersity Of Simo Ductile Iron On High Temperature Performance During Static Oxidation, Semen Naumovich Lekakh, Asebi Bofah, Larry A. Godlewski, Mei Li

Materials Science and Engineering Faculty Research & Creative Works

High silicon and molybdenum (SiMo) ductile iron is commonly used for car exhaust systems, and its micro-structural dispersity depends on intrinsic parameters, which include alloy composition and inoculation efficiency, as well as extrinsic factors, such as casting wall thickness and molding material, which define cooling rate during solidification. Micro-structural dispersity is referred to as the degree of heterogeneity of sizes of structural constituencies within the microstructure. A variation in the micro-structural dispersity could impact the high temperature performance of SiMo ductile iron during static oxidation and transient thermo-mechanical loading conditions. In this study, static high temperature tests were performed on …

Zero-Power Ac Current Sensor, Omar Aragonez

Mechanical Engineering ETDs

In this study, a magnetic piezoelectric cantilever powered AC current and frequency sensor is proposed. This paper covers the configuration of the experimental setup, finite element modeling of the magnetic coupling, and the optimal spatial location of the magnetic proof mass in relation to the wire for smart grid applications. Solid and stranded copper wires of various gauges were used and carried current up to 30A. The magnets act as a proof mass to lower the frequency while also coupling to the magnetic field generated by the current carrying wire. The frequency of the AC current produces a sinusoidal force …

Let's Get Serious About It: Plastic-Free Campus Initiative, Geoffrey Kain, Camdyn Doucette, Regan Bossie

Sustainability Conference

On February 23, 2022, the UN agreed to start negotiating a world-first global treaty on plastic waste--since nearly 200 nations unanimously agreed to move toward a legally binding plastics treaty by 2024. In 2019 the UN Environmental Programme report highlighted that "our world is drowning in plastic." As with the climate change crisis (to which plastics production and disposal are also linked), the data resoundingly illustrate the imminent systemic threat that disposable plastics pose to the world's seas, freshwater sources, soils, food supply, air, and species. Nevertheless, plastics production is predicted to rise dramatically over the next 20 years, with …

Magnetic And Structural Effects In Interfacial Magnetism: Molecular Magnets And Ferrimagnetic Alloys, Jenae E. Shoup

USF Tampa Graduate Theses and Dissertations

Magnetic thin films are important for technological applications such as giant magnetoresistance,spin valves and magnetic tunnel junctions. A key feature for these applications to be possible is the interface between two materials. We will be studying two types of thin film magnetism; interfaces between molecular carbon, C60, and non-magnetic/ferromagnetic material and two layers of ferrimagnetic rare earth/ transition metal alloys (RE/TM) that have similar composition to engineer a magnetic tunable interface.

One of the most unexpected spin-related properties of C60 is the emergence of room-temperature ferromagnetism in multilayer films of C60 and non-ferromagnetic transition metals such as Cu or Mn …

Method Of Embedded Imperfections For The Direct Simulation Of Deformation Instabilities In Film-Substrate Structures, Siavash Nikravesh Kazeroni

Mechanical Engineering ETDs

In this dissertation, a novel finite-element methodology called “embedded imperfections” is proposed and employed for computationally simulating various types of deformation instabilities observed in film-substrate structures subjected to mechanical loading. The approach involves the incorporation of elements having distinctive material properties within the film-substrate interface. One can interpret this practice as a deliberate distribution of material defects within the numerical model. It has been shown that embedded imperfections not only can trigger the onset of instability, but also can lead to “direct” simulation of deformation instability problems in that primary and subsequent instability modes can all be captured in a …

Limits Of Detection Of Mycotoxins By Laminar Flow Strips: A Review, Xinyi Zhao, Hugh Byrne, Christine M. O’Connor, James Curtin, Furong Tian

Articles

Mycotoxins are secondary metabolic products of fungi. They are poisonous, carcinogenic, and mutagenic in nature and pose a serious health threat to both humans and animals, causing severe illnesses and even death. Rapid, simple and low-cost methods of detection of mycotoxins are of immense importance and in great demand in the food and beverage industry, as well as in agriculture and environmental monitoring, and, for this purpose, lateral flow immunochromatographic strips (ICSTs) have been widely used in food safety and environmental monitoring. The literature to date describing the development of ICSTs for the detection of different types of mycotoxins using …

Theranostic Copolymers Neutralize Reactive Oxygen Species And Lipid Peroxidation Products For The Combined Treatment Of Traumatic Brain Injury, Aaron Priester, Richard Waters, Ashleigh Abbott, Krista Hilmas, Klaus Woelk, Hunter A. Miller, Aria W. Tarudji, Connor C. Gee, Brandon Mcdonald, Forrest M. Kievit, Anthony J. Convertine

Chemistry Faculty Research & Creative Works

Traumatic brain injury (TBI) results in the generation of reactive oxygen species (ROS) and lipid peroxidation product (LPOx), including acrolein and 4-hydroxynonenal (4HNE). The presence of these biochemical derangements results in neurodegeneration during the secondary phase of the injury. The ability to rapidly neutralize multiple species could significantly improve outcomes for TBI patients. However, the difficulty in creating therapies that target multiple biochemical derangements simultaneously has greatly limited therapeutic efficacy. Therefore, our goal was to design a material that could rapidly bind and neutralize both ROS and LPOx following TBI. To do this, a series of thiol-functionalized biocompatible copolymers based …

Machine Learning Assisted Discovery Of Shape Memory Polymers And Their Thermomechanical Modeling, Cheng Yan

LSU Doctoral Dissertations

As a new class of smart materials, shape memory polymer (SMP) is gaining great attention in both academia and industry. One challenge is that the chemical space is huge, while the human intelligence is limited, so that discovery of new SMPs becomes more and more difficult. In this dissertation, by adopting a series of machine learning (ML) methods, two frameworks are established for discovering new thermoset shape memory polymers (TSMPs). Specifically, one of them is performed by a combination of four methods, i.e., the most recently proposed linear notation BigSMILES, supplementing existing dataset by reasonable approximation, a mixed dimension (1D …

Effects Of Carrier, Leveller, And Booster Concentrations On Zinc Plating From Alkaline Zincate Baths, Abdul Jalil Mohammed, Michael S. Moats

Materials Science and Engineering Faculty Research & Creative Works

Organic additives are required for alkaline zincate plating baths to obtain an acceptable coating on steel for corrosion protection. The effects and possible interactions of three commercial additives (Eldiem Carrier, Eldiem Booster, and Bright Enhancer 2x on zinc electrodeposition from a high-concentration alkaline zincate bath were investigated. Visually acceptable deposits were produced within the current density range of 130 to 430 A m^-2 for most additive conditions examined. Over concentration ranges examined, decreasing the booster concentration led to brighter zinc deposits, and an interaction between the carrier and the booster was detected. The additives fostered the formation of compact …

Mechanical Behavior Of Materials, Joshua P. Steimel

Pacific Open Texts

This text serves to cover in more detail solid mechanics concepts and specifically the material response to stress and strain. This text spans solid mechanics concepts from stress and strain at an atomistic length scale, to linear elasticity, anisotropy, linear viscoelasticity, plasticity, dislocation generation and interactions, and fracture.

Quasi In-Situ Ebsd Analysis Of Twinning-Detwinning And Slip Behaviors In Textured Az31 Magnesium Alloy Subjected To Compressive-Tensile Loading, Yuzhi Zhu, Dewen Hou, Qizhen Li

Materials Science and Engineering Faculty Publications and Presentations

Twinning and detwinning behavior, together with slip behavior, are studied in a textured AZ31 magnesium alloy under compressive and tensile strains along the rolling direction (RD) after each interrupted mechanical test via quasi in-situ electron backscattered diffraction technique. The results show that twinning firstly takes place under the compressive strain along the RD. With the increasing compressive strain, {1012} tensile twins firstly nucleate, then propagate, and finally thicken. While under a reversed tensile strain along the RD, detwinning occurs. No nucleation happens during detwinning. Thus, tensile twins can detwin at lower tensile strain, followed by thinning, shortening, and vanishing. Slips …