Synthesis And Characterization Of Perovskite-Based Materials For Memory Device Application,
2021
Universiti Malaya
Synthesis And Characterization Of Perovskite-Based Materials For Memory Device Application, Gregory Thien Soon How
Student Works (2020-2029)
This project aims to study the resistive switching behaviour in memory devices using perovskites-based structures. A hybrid organic-inorganic lead halide perovskite was studied in this project, specifically methylammonium lead triiodide, CH3NH3PbI3 or MAPbI3 perovskite. The effect of the various counter electrodes in MAPbI3 perovskite was investigated by fabricating MAPbI3 perovskite on Indium Tin Oxide (ITO). Three commonly used electrodes which are Aluminium (Al), Silver (Ag), and Gold (Au) were thermally evaporated on top of the MAPbI3 perovskite layer. It was found that the ITO/MAPbI3/Al exhibits Resistive Random Access Memory (ReRAM) behaviour with SET voltage (VSET) of 4.5 V and RESET …
Development Of Engineered Soil Surrogates For Modeling Natural Soil Sorption Behavior,
2021
Louisiana State University
Development Of Engineered Soil Surrogates For Modeling Natural Soil Sorption Behavior, Ghada Yehia Abdalla
LSU Doctoral Dissertations
The land produces more than 95% of the global food supply, and with a continuously growing population, we need to optimize the use of the available agricultural land. Soil organic matter (SOM) is an essential component of soils, especially concerning their fertility and sorption behavior. The chemical composition of the SOM consists of lipids, lignin, and cellulose. However, the heterogeneous and complex nature of SOM, and real soils, makes their study challenging and introduces uncontrollable factors.
Therefore, structural mimics of natural soils with increasing complexity representing the real soil functionality were synthesized and evaluated for bulk properties related to their …
Synthesis Of New Anilinoquinazoline Derivatives As Potential Anticancer Agents: Antiproliferative Activity, Molecular Docking And Molecular Dynamics Studies,
2021
Universiti Malaya
Synthesis Of New Anilinoquinazoline Derivatives As Potential Anticancer Agents: Antiproliferative Activity, Molecular Docking And Molecular Dynamics Studies, Muhammad Kumayl Abdul Wahab
Student Works (2020-2029)
Current reversible epidermal growth factor (EGFR) tyrosine kinase inhibitors of the non-small cell lung cancer (NSCLC) have been resisted by T790M mutation, while irreversible inhibitors introduced to overcome the mutation have faced resistance from C797S mutation. In the effort to discover potential reversible EGFR inhibitors, two series of anilinoquinazoline derivatives were synthesized and characterized, studied for their in vitro antiproliferative activity against NSCLC cell lines, namely A549, H1650 and H1975, and studied for the plausible binding mode in epidermal growth factor receptor kinases with different mutations through molecular docking. In the first series, the anilinoquinazoline scaffold was derivatized through the …
Numerical Reconstruction Of Spalled Particle Trajectories In An Arc-Jet Environment,
2021
University of Kentucky
Numerical Reconstruction Of Spalled Particle Trajectories In An Arc-Jet Environment, Raghava S. C. Davuluri, Sean C. C. Bailey, Kaveh A. Tagavi, Alexandre Martin
Mechanical Engineering Faculty Publications
To evaluate the effects of spallation on ablative material, it is necessary to evaluate the mass loss. To do so, a Lagrangian particle trajectory code is used to reconstruct trajectories that match the experimental data for all kinematic parameters. The results from spallation experiments conducted at the NASA HYMETS facility over a wedge sample were used. A data-driven adaptive methodology was used to adapts the ejection parameters until the numerical trajectory matches the experimental data. The preliminary reconstruction results show that the size of the particles seemed to be correlated with the location of the ejection event. The size of …
Polyesters With Main And Side Chain Phosphoesters As Structural Motives For Biocompatible Electrospun Fibres,
2021
Royal College of Surgeons in Ireland
Polyesters With Main And Side Chain Phosphoesters As Structural Motives For Biocompatible Electrospun Fibres, André E. Polloni, Viviane Chiaradia, Ronaldo José F.C. Do Amaral, Cathal Kearney, Brian Gorey, Débora De Oliveira, José V. De Oliveira, Pedro H.H. De Araújo, Claudia Sayer, Andreas Heise
Articles
Phosphoester containing polymers are promising materials in biomedical applications due to their biocompatibility and biodegradability. Utilising thiol-ene chemistry, the synthesis of two novel structural polymer motives combining polyesters and phophoester groups was explored. The first polymer was obtained by coupling ene-functional poly(thioether-phosphoester) with thiol functional poly(pentadecalactone). While the coupling reaction was successful, yields remained low presumably due to inadequate endgroup stoichiometry. The second polymer comprised phosphoester side groups conjugated to unsaturated poly(globalide). Double bond conversions up to 84% were achieved depending of the type of phosphoester thiol and relative reactant ratios. The resulting polymers transitioned from solid semicrystaline to liquid …
Valorization Of Xylan In Agroforestry Waste Streams,
2021
West Virginia University
Valorization Of Xylan In Agroforestry Waste Streams, Harrison Appiah
Graduate Theses, Dissertations, and Problem Reports (ETD)
Valorization of Xylan in Agroforestry Waste Streams.
Harrison Appiah
Microwave-assisted deep eutectic solvent and gamma-valerolactone metallic chloride catalyzed conversion of xylan to furfural were investigated using a 2x3 factorial experimental design at two levels of percent microwave power, reaction time, and catalyst concentration. The levels of each factor studied were (20%, 60% microwave power, 2, 4 minutes, and 10, 20mg) respectively. The effect of three metallic chloride catalysts (LiCl, FeCl3.6H20, CuCl2) on the conversion of xylan to furfural was also investigated. The gamma-valerolactone-ferric chloride sent system exhibited the highest mean yield of furfural (56.50%). The next highest furfural yield of …
Toward Understanding Large Deflection Bending Of 3d Printed Ninjaflex®,
2021
University of Nevada, Las Vegas
Toward Understanding Large Deflection Bending Of 3d Printed Ninjaflex®, Lucas K. Gallup, Mohamed Trabia, Brendan O’Toole, Youssef Fahmy
College of Engineering Faculty Research
NinjaFlex® is a thermoplastic polyurethane filament that is primarily used for 3D printing. Aside from its low cost and availability, this material is highly flexible, durable, and has a low coefficient of friction. While NinjaFlex® was introduced approximately two decades ago, a comprehensive understanding of the filament’s mechanical behavior, especially in the context of the effect of 3D printing, is still lacking. The goal of this research is to gain a better understanding of the behavior of 3D printed NinjaFlex® specimens when subjected to bending loads that cause large deflection. A series of experiments were conducted to test the bending …
Recently Developed Carbohydrate Based Gelators And Their Applications,
2021
Old Dominion University
Recently Developed Carbohydrate Based Gelators And Their Applications, Joedian Morris, Jonathan Bietsch, Kristen Bashaw, Guijun Wang
Chemistry & Biochemistry Faculty Publications
Carbohydrate based low molecular weight gelators have been an intense subject of study over the past decade. The self-assembling systems built from natural products have high significance as biocompatible materials and renewable resources. The versatile structures available from naturally existing monosaccharides have enriched the molecular libraries that can be used for the construction of gelators. The bottom-up strategy in designing low molecular weight gelators (LMWGs) for a variety of applications has been adopted by many researchers. Rational design, along with some serendipitous discoveries, has resulted in multiple classes of molecular gelators. This review covers the literature from 2017-2020 on monosaccharide …
Effect Of Heat Treatment On Microstructure And Hardness Of A Worn Rail Repaired Using Laser Powder Deposition,
2021
University of Nevada, Las Vegas
Effect Of Heat Treatment On Microstructure And Hardness Of A Worn Rail Repaired Using Laser Powder Deposition, Ershad Mortazavian, Zhiyong Wang, Hualiang Teng
Mechanical Engineering Faculty Research
The frequent replacement of worn rails on tracks brings an immense economic burden on the railroad industry, and also causes significant interruptions to railroad operation. Restoration of worn rails via laser powder deposition (LPD) can considerably reduce the associated maintenance costs. This study was focused on the use of LPD to repair the worn profile of a standard U.S. rail. The microstructure of the 304L stainless steel deposits with a minimum hardness of 85 HRB was composed of austenite, δ-ferrite, and sigma. Micropores were dispersed throughout the deposit, and microcracks were found at the rail-deposition interface. The pearlitic rail substrate …
Multi-Level Analysis Of Atomic Layer Deposition Barrier Coatings On Additively Manufactured Plastics For High Vacuum Applications,
2021
Michigan Technological University
Multi-Level Analysis Of Atomic Layer Deposition Barrier Coatings On Additively Manufactured Plastics For High Vacuum Applications, Nupur Bihari
Dissertations, Master's Theses and Master's Reports
While hardware innovations in micro/nano electronics and photonics are heavily patented, the rise of the open-source movement has significantly shifted focus to the importance of obtaining low-cost, functional and easily modifiable research equipment. This thesis provides a foundation of open source development of equipment to aid in the micro/nano electronics and photonics fields.
First, the massive acceptance of the open source Arduino microcontroller has aided in the development of control systems with a wide variety of uses. Here it is used for the development of an open-source dual axis gimbal system. This system is used to characterize optoelectronic properties of …
Nanostructured Copper Selenide As An Ultrasensitive And Selective Non-Enzymatic Glucose Sensor,
2021
Missouri University of Science and Technology
Nanostructured Copper Selenide As An Ultrasensitive And Selective Non-Enzymatic Glucose Sensor, Siddesh Umapathi, Harish Singh, Jahangir Masud, Manashi Nath
Chemistry Faculty Research & Creative Works
CuSe nanostructures exhibit high-efficiency for glucose detection with high sensitivity (19.419 mA mM-1 cm-2) and selectivity at a low applied potential of +0.15 V vs. Ag|AgCl, a low detection limit of 0.196 μM and a linear range of glucose detection from 100 nm. to 40 μM. This journal is
Development Of Synthetic Coal Char Simulant For Microwave Conversion Studies: A Computationally-Driven Approach,
2021
West Virginia University
Development Of Synthetic Coal Char Simulant For Microwave Conversion Studies: A Computationally-Driven Approach, Kevin A. Hager
Graduate Theses, Dissertations, and Problem Reports (ETD)
Recent experimental demonstration of new reaction windows for coal char/methane reactions that are less energy-intensive, provides innovation for modular reactors. However, the correlation of the exact mechanism for the enhancement of these reaction windows is not certain. This study investigates the simplification of these experimental studies by developing a well-characterized coal char simulant. The approach involves using a computational approach to screen macroscopic composition to replicate the dielectric and compositional response of actual char. This study is focused on PRB coal char. A discrete element method (DEM) technique was used to simulate the packing of coal chars to give the …
Characterization Of Modern Ammunition And Background Profiles: A Novel Approach And Probabilistic Interpretation Of Inorganic Gunshot Residue,
2021
West Virginia University
Characterization Of Modern Ammunition And Background Profiles: A Novel Approach And Probabilistic Interpretation Of Inorganic Gunshot Residue, Korina Layli Menking-Hoggatt
Graduate Theses, Dissertations, and Problem Reports (ETD)
Gunshot residue (GSR) can provide essential clues in gun-related investigations. The standard practice for GSR analysis uses SEM-EDS, with the capability for single particle elemental and morphological analysis. However, the method is time-consuming and based on categorical classification models without considering case circumstances. Therefore, complementary and more encompassing methods are needed to improve evidence interpretation of modern ammunition. This research aims to fill these demands by developing standard materials and alternative methods to characterize and interpret IGSR.
This study developed primer GSR (pGSR) standards from sixty discharged primers that were fully characterized by three techniques. The number of GSR particles, …
Fabrication Of Metal-Silicon Nanostructures By Reactive Laser Ablation In Liquid,
2021
Virginia Commonwealth University
Fabrication Of Metal-Silicon Nanostructures By Reactive Laser Ablation In Liquid, Eric J. Broadhead
Theses and Dissertations
Metal-silicon nanostructures are a growing area of research due to their applications in multiple fields such as biosensing and catalysis. In addition, silicon can provide strong support effects to metal nanoparticles while being more cost effective than traditionally used supports, like titania. Traditional wet-chemical methods are capable of synthesizing metal-silicon nanostructures with a variety of composition and nanoparticle shapes, but they often require high temperatures, toxic solvents, strong reducing agents, or need capping agents added to stabilize the nanoparticles. Laser processing is an emerging technique capable of synthesizing metal-silicon composite surfaces that offers a faster, simpler, and greener synthesis route …
Nanopore Detection Of Long Time-Scale Single Metallic Cluster Conformational Changes And Surface Ligand Exchange,
2021
Virginia Commonwealth University
Nanopore Detection Of Long Time-Scale Single Metallic Cluster Conformational Changes And Surface Ligand Exchange, Bobby D. Cox
Theses and Dissertations
Single molecule nanopore spectroscopy serves as an emerging tool for studying small molecules in aqueous environments without the need for additional chemical labels. Recently it has been seeing increased use as a tool for investigating small metallic nanoparticles and clusters. These clusters consist of a handful of metallic atoms (e.g. Au18) and are regularly ‘passivated’ with organic ligands to provide functionality and protect against aggregation. There has been a widening gap in research studying the surface kinetics of these passivating ligands at the single molecule level as well as during the exchange process. In this work we investigated these surface …
Determining Material Structures And Surface Chemistry By Genetic Algorithms And Quantum Chemical Simulations,
2021
University of Kentucky
Determining Material Structures And Surface Chemistry By Genetic Algorithms And Quantum Chemical Simulations, Josiah Jesse Roberts
Theses and Dissertations--Chemistry
With the advent of modern computing, the use of simulation in chemistry has become just as important as experiment. Simulations were originally only applicable to small molecules, but modern techniques, such as density functional theory (DFT) allow extension to materials science. While there are many valuable techniques for synthesis and characterization in chemistry laboratories, there are far more materials possible than can be synthesized, each with an entire host of surfaces. This wealth of chemical space to explore begs the use of computational chemistry to mimic synthesis and experimental characterization. In this work, genetic algorithms (GA), for the former, and …
Synthesis, Crystal Engineering, And Material Properties Of Small-Molecule Organic Semiconductors,
2021
University of Kentucky
Synthesis, Crystal Engineering, And Material Properties Of Small-Molecule Organic Semiconductors, Emma Holland
Theses and Dissertations--Chemistry
Small-molecule organic materials are of increasing interest for electronic and photonic devices due to their solution processability and tunability, allowing devices to be fabricated at low temperature on flexible substrates and offering utility in specialized applications. This tunability is the result of functionalization through careful synthetic strategy to influence both material properties and solid-state arrangement, both crucial variables in device applications. Functionalization of a core molecule with various substituents allows the fine-tuning of optical and electronic properties, and functionalization with solubilizing groups allows some degree of control over the solid- state order, or crystal packing. These combinations of core chromophores …
Plasmon Enhanced Single Molecule Fluorescence In Zero Mode Waveguides (Zmws),
2021
University of Kentucky
Plasmon Enhanced Single Molecule Fluorescence In Zero Mode Waveguides (Zmws), Abdullah Masud
Theses and Dissertations--Chemistry
Plasmonic nanostructures are an extensive research focus due to their ability to modify the photophysical properties of nearby fluorophores. Surface plasmons (SP), defined as the collective oscillation of delocalized electrons, are the fundamental characteristic primarily responsible for altering those photophysical properties. Studying fluorophores at the single-molecule level has received significant attention since more specific information can be extracted from single molecule-based studies, which otherwise could be obscured in ensemble studies. However, single-molecule studies are inherently challenging because the signal from a single molecule is usually dim, making it difficult to detect. The situation is even worse in a crowded environment …
Molecular Recognition Of Pet Depolymerization Products And Beta-Cyclodextrin,
2021
The University of Akron
Molecular Recognition Of Pet Depolymerization Products And Beta-Cyclodextrin, Thomas Palisin
Williams Honors College, Honors Research Projects
Using molecular recognition techniques to determine the binding constant of the host-guest relationships of the depolymerization products of polyethylene terephthalate (PET) and cyclodextrin species. The main method of data collection used was florescence spectroscopy. Using a titration method and measuring the florescence intensity, a nonlinear regression was used to determine the binding constant.
Predicting Material Properties: Applications Of Multi-Scale Multiphysics Numerical Modeling To Transport Problems In Biochemical Systems And Chemical Process Engineering,
2021
University of Kentucky
Predicting Material Properties: Applications Of Multi-Scale Multiphysics Numerical Modeling To Transport Problems In Biochemical Systems And Chemical Process Engineering, Tom Pace
Theses and Dissertations--Physics and Astronomy
Material properties are used in a wide variety of theoretical models of material behavior. Descriptive properties quantify the nature, structure, or composition of the material. Behavioral properties quantify the response of the material to an imposed condition. The central question of this work concerns the prediction of behavioral properties from previously determined descriptive properties through hierarchical multi-scale, multiphysics models implemented as numerical simulations. Applications covered focus on mass transport models, including sequential enzyme-catalyzed reactions in systems biology, and an industrial chemical process in a common reaction medium.
