Physical Chemistry Commons^™

Impacts Of Key Degradation Byproducts On Amine Scrubbing For Post-Combustion Carbon Capture, Thomas Jorgensen

Theses and Dissertations--Chemistry

The increasing atmospheric CO₂ concentration causes significant concern about global warming and its environmental impact. Industrial sectors, including power generation, transportation, and production factories, contribute most of the anthropogenic sources of CO₂ emissions. Researchers search for methods to mitigate these CO₂ emissions without compromising the benefits of industrial processes, including CO₂ capture, utilization, and sequestration (CCUS). Post-combustion carbon capture (PCCC) by amine scrubbing is the most technology ready CCUS, with various pilot-scale projects worldwide showing small-scale to fully operational plants. While researchers have made significant progress in amine scrubbing, they strive to improve the efficiency and …

Spiral Wave Teleportation And Multiplex Network Synchronization In Light Sensitive Belousov-Zhabotinsky Systems, Shannyn Alicia Tyler

Graduate Theses, Dissertations, and Problem Reports (ETD)

We experimentally and computationally investigate dynamical behaviors in excitable and oscillatory media using light sensitive Belousov-Zhabotinsky (BZ) systems. These systems are not in a state of thermodynamic equilibrium, and have been proven to show various interesting phenomena including spatiotemporal patterns, self-organization, and chaos. We utilize the BZ reaction, a nonlinear chemical reaction, known for its relaxation-type oscillations, to explore the dynamics of these systems.

We examine spiral wave teleportation in an excitable media as an effective alternate defibrillation method. Spiral waves have emerged as a key phenomenon associated with the initiation and persistence of cardiac arrhythmias. Using a light sensitive …

Use Of Interlaboratory Studies For The Development Of Consensus-Based Criteria For The Elemental Analysis Of Electrical Tapes, Lacey M. Leatherland

Graduate Theses, Dissertations, and Problem Reports (ETD)

Tape evidence is often used in criminal cases involving violent crimes, kidnappings, improvised explosive devices (IEDs), and drug trafficking. This evidence can reveal potential links between suspects, items, or scenes. The forensic examination of electrical tape can provide investigative leads or offer support to alternative hypotheses evaluated in the courtroom. A conventional analytical scheme includes microscopic examination, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy Energy Dispersive Spectrometry (SEM-EDS), and Pyrolysis Gas Chromatography Mass Spectrometry (Py-GC/MS). Elemental analysis of electrical tapes is commonly achieved using SEM-EDS; however, recent scientific literature suggests that this analysis can evolve from using SEM-EDS to …

Concentration Effects Of Ytterbium(Iii) Ions On The Physical, Structural, Thermal, And Optical Properties Of Barium Phosphate Glasses, Richard Amesimenu

College of Graduate Studies: Theses & Dissertations

Ytterbium(III)-doped glasses are widely known for their application in near-infrared (NIR) lasers and nowadays attract attention for solar spectral conversion in photovoltaic cells. In this study, the effects of ytterbium(III) concentration on the physical, structural, optical, and thermal characteristics of Yb-doped phosphate glasses were investigated. The glasses were synthesized using the melt-quenching technique with nominal compositions of 50P₂O₅:(50 – xBaO):xYb₂O₃ (x = 0, 0.5, 1.0, 2.0, 3.0 and 4 mol%). The properties were then examined by density and related parameters, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform-infrared …

Assessing The Performance Of Newly Developed Silica Nanoparticles Against Lead And Phosphate Ion Removal From Contaminated Solutions Using Adsorption Isotherm, Hasan Shamseddine, Nour Abi Aad, Rami Oweini, Ghassan Younes

BAU Journal - Science and Technology

This study investigates the removal of Lead and Phosphate ion from aqueous solution using new silica nanoparticles doped with europium (H1) which was characterized using Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), Fourier-transform Infrared Spectroscopy (FTIR). The aim of this research is to develop a novel adsorbent material that can efficiently remove contaminated ions from wastewater or aqueous solutions. The adsorption of lead and phosphate ion onto the silica nanoparticles is investigated, and the efficiency of this removal is evaluated. Equilibrium data analysis reveals linear fitting with Langmuir isotherm with 24.76 mg/g Lead ion uptake, while for phosphate the …

An In-Situ Raman Spectroscopic Study On The Interfacial Process Of Carbonate-Based Electrolyte On Nanostructured Silver Electrode, Yu Gu, Yuan-Fei Hu, Wei-Wei Wang, En-Ming You, Shuai Tang, Jian-Jia Su, Jun Yi, Jia-Wei Yan, Zhong-Qun Tian, Bing-Wei Mao

Journal of Electrochemistry

The solid-electrolyte interphase (SEI) plays a key role in anodes for rechargeable lithium-based battery technologies. However, a thorough understanding in the mechanisms of SEI formation and evolution remains a major challenge, hindering the rapid development and wide applications of Li-based batteries. Here, we devise a borrowing surface-enhanced Raman scattering (SERS) activity strategy by utilizing a size optimized Ag nanosubstrate to in-situ monitor the formation and evolution of SEI, as well as its structure and chemistry in an ethylene carbonate-based electrolyte. To ensure a reliable in-situ SERS investigation, we designed a strict air-tight Raman cell with a three-electrode configuration. Based on …

Intelligent Control Based On Bp Artificial Neural Network For Electrochemical Nitrate Removal, Xin-Wan Zhang, Guang-Yuan Meng, Li-Qiang Fang, Ding-Ming Chang, Tong Li, Jin-Wen Hu, Peng Chen, Yong-Di Liu, Le-Hua Zhang

Journal of Electrochemistry

Achieving effective control of parameters in the process of nitrate wastewater treatment is critical to electrochemical water treatment. The powerful nonlinear mapping ability, self-adaptation and self-learning ability of neural network technology can optimize the electrochemical processing. However, there are few researches in this direction. Hence, based on the test data of the electrochemical reduction of nitrate, an electrochemical prediction model was established by using the BP neural network algorithm. Considering the correlation of various parameters in the electrochemical process, the reaction time, initial nitrate nitrogen concentration, pH and current density were determined as the input layer of the BP neural …

Nitrogen-Doped Graphite Felt On The Performance Of Aqueous Quinone-Based Redox Flow Batteries, Heng Zhang, Li-Xing Xia, Shan Jiang, Fu-Zhi Wang, Zhan-Ao Tan

Journal of Electrochemistry

Modification of electrode is vitally important for achieving high energy efficiency in aqueous quinone-based redox flow batteries (AQRFBs). The modification of graphite felt (GF) was carried out by means of urea hydrothermal reaction, and simultaneously, the effects of hydrothermal reaction time on the functional groups and surface structure of nitrogen-doped graphite felt were studied. The surface morphology and defect, element content and surface chemical state of the modified electrode were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) test, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The electrochemical performance of the modified electrodes was evaluated by cyclic voltammetry, electrochemical impedance …

Electrochemical Performance Of Porous Ceramic Supported Tubular Solid Oxide Electrolysis Cell, Heng-Ji Wang, Wen-Guo Chen, Zhou-Yi Quan, Kai Zhao, Yi-Fei Sun, Min Chen, Ogenko Volodymyr

Journal of Electrochemistry

Solid oxide electrolysis cell (SOEC) is an efficient and clean energy conversion technology that can utilize electricity obtained from renewable resources, such as solar, wind, and geothermal energy to electrolyze water and produce hydrogen. The conversion of abundant intermittent energy to hydrogen energy would facilitate the efficient utilization of energy resources. SOEC is an all-ceramic electrochemical cell that operates in the intermediate to high temperature range of 500–750 ℃. Compared with traditional low temperature electrolysis technology (e.g., alkaline or proton exchange membrane cells operating at ~100 ℃), the high-temperature SOEC can increase the electrolysis efficiency from 80% to ~100%, providing …

Exploring Soybean Oil-Based Polyol And Effect Of Non-Halogenated Flame Retardants In Rigid Polyurethane Foam, Sahithi Kondaveeti

Electronic Theses & Dissertations

To address the increasing demand for sustainable biomaterials due to the depletion of fossil fuel resources and growing environmental concerns, a new type of biodegradable and environmentally friendly rigid polyurethane foam (RPUF) has been synthesized. These foams are derived from chemically modified soybean oil-based polyol obtained from soybean oil by epoxidation followed by a ring-opening reaction. Polyurethane foam is generally used in construction, furniture, and automobile industries but is highly flammable and releases toxic gases and smoke during combustion. In this study, a highly efficient synergistic effect halogen-free flame-retardant (FR) melamine salt, 2-carboxyethyl(phenyl)phosphinic acid melamine salt (CMA) was synthesized from …

Enhanced Mechanical Strength Of Soybean Oil-Based Non-Isocyanate Polyurethane Adhesive For Wood Application By Introducing Nanofillers, Vatsal Chaudhari

Electronic Theses & Dissertations

Polyurethane (PU) is a versatile material that finds extensive use in various industries including bedding, construction, automotive, and packaging. Historically, this particular polymer relied significantly on petrochemical resources, a practice that was considered to have negative environmental impacts. The conventional method for preparing PU involves the use of isocyanate, which is a disadvantage due to its negative impact on the environment and human health. The resolution of this problem entails identifying an appropriate substitute for petroleum-derived products that minimize their impact on both the environment and human health. The researchers earlier utilized soybean oil, for the formulation of PUs in …

Castor Oil Polyol-Based Adhesives With Additional Crosslinker For Improvement In Mechanical And Thermal Properties., Yash Desai

Electronic Theses & Dissertations

Polyurethanes (PU) have been promising polymeric materials with many applications, including adhesives. Projecting an estimated revenue from 42.8 billion $ in 2021 to 61.5 billion $ by 2026. However, a large number of PU adhesives are sourced from petroleum products. Therefore, to lower the dependence on non-renewable resources and provide sustainable and affordable alternatives. In this work will synthesize bio-based adhesives of polyurethane from modified castor oil-based polyol. Generally, polyurethane reaction depends on the properties of polyol and isocyanates. The most important aspect of these reactions is the OH number of the polyol, which is responsible for the crosslinking and …

Oxidation Of Ethanolamine By Potassium Permanganate In The Presence And Absence Of Sodium Dodecyl Sulphate: A Kinetic Study In An Acidic Medium, Dayo Latona

Makara Journal of Science

The kinetics of ethanolamine oxidation by acidified KMnO₄ was investigated in the absence and presence of sodium dodecyl sulfate (SDS) was investigated using a pseudo-first-order kinetics approach, with [ethanolamine]_o >> [KMnO₄]_o. The measurements were conducted at λ_max = 525 nm using an ultraviolet/visible-1800 Shimadzu spectrophotometer. The stoichiometry showed that 2 moles of KMnO₄ were consumed by 5 moles of ethanolamine in the aqueous medium. The reaction orders in both the aqueous and micellar media remained the same with a first-order dependence on [KMnO₄] and [ethanolamine] and a fractional-order dependence on [H …

Jwst: Deuterated Pahs, Pah-Nitriles, And Pah 4 Overtone And Combination Bands I: Program Description And First Look, C. Boersma, L. J. Allamandola, Vincent J. Esposito, A. Maragkoudakis, J. D. Bregman, P. Temi, T. J. Lee, R. C. Fortenberry, E. Peeters

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

A first look is taken at the NIRSpec 1–5 μm observations from James Webb Space Telescope program 1591 that targets seven objects along the low-mass stellar life cycle with polycyclic aromatic hydrocarbon (PAH) emission. Spectra extracted from a 1'.'5 radius circular aperture are explored, showing a wealth of features, including the 3 μm PAH complex, the PAH continuum, and atomic and molecular emission lines from H i, He, H₂, and other species. CO₂- and H₂O-ice absorption and CO emission is also seen. Focusing on the bright-PDR position in M17, the PAH CH stretch falls …

Ionically Crosslinked Cellulose Nanocrystals By Metal Nitrates For The Preparation Of Stable Emulsions With Tunable Interface Properties, Joseph Batta-Mpouma, Gurshagan Kandhola, Jin-Woo Kim

Materials Science and Engineering Faculty Publications and Presentations

Biologically extracted cellulose nanocrystals (CNCs) are rod-like and amphiphilic materials with surface-exposed (hydrophilic sites) and hidden (hydrophobic sites) hydroxyl groups. These physicochemical characteristics make CNCs suitable for use as emulsifying agents to stabilize emulsions. Stable oil-in-water emulsions, using sulfated (i.e., – SO₃−) CNCs that were ionically crosslinked with alkaline-earth (i.e., Mg ²⁺) or transition-d-block (i.e., Zn ²⁺) metal cations, were developed without the use of any synthetic surfactants or prior functionalization of pure CNCs with hydrophobic molecules. Various emulsion surface properties such as interfacial tension, surface charge, surface chemistry, as well as rheology were characterized. Ionically …

Stress-Sensing In Flexible Epoxy Adhesives, Christine Rukeyser

Honors Theses

In mechanochemistry, mechanical force causes a chemical change using small molecules, called mechanophores, by covalently connecting them into polymer materials. Stress-sensing mechanophores give a visual signal of mechanical force on the molecular level within a material. To our knowledge, stress-sensing mechanophores have never been incorporated into a commercially available epoxy kit. In this work, the characterization of two 3MTM Scotch-Weld TM Epoxy Adhesive kits: DP100 Plus Clear and DP190 Translucent have been completed through FT-IR Spectroscopy. The addition of the mechanophore spiropyran to the 3M kits will be discussed; as well as preparation and characterization of three dimerized anthracene derivatives. …

Deficiency Of Acute-Phase Serum Amyloid A Exacerbates Sepsis-Induced Mortality And Lung Injury In Mice, Ailing Ji, Andrea C. Trumbauer, Victoria P. Noffsinger, Luke W. Meredith, Brittany Dong, Qian Wang, Ling Guo, Xiangan Li, Frederick C. De Beer, Nancy R. Webb, Lisa R. Tannock, Marlene E. Starr, Christopher M. Waters, Preetha Shridas

Saha Cardiovascular Research Center Faculty Publications

Serum amyloid A (SAA) is a family of proteins, the plasma levels of which may increase >1000-fold in acute inflammatory states. We investigated the role of SAA in sepsis using mice deficient in all three acute-phase SAA isoforms (SAA-TKO). SAA deficiency significantly increased mortality rates in the three experimental sepsis mouse models: cecal ligation and puncture (CLP), cecal slurry (CS) injection, and lipopolysaccharide (LPS) treatments. SAA-TKO mice had exacerbated lung pathology compared to wild-type (WT) mice after CLP. A bulk RNA sequencing performed on lung tissues excised 24 h after CLP indicated significant enrichment in the expression of genes associated …

Computational Investigations Of Bond Breaking Processes Using Dft And Td-Dft Approaches., Saurav Parmar

Electronic Theses and Dissertations

The efficient application of DFT and TD-DFT has been harnessed to study bond-breaking processes in some molecules which play a prominent role in enzymatic reactions. The first application includes Radical S-adenosyl methionine (SAM) enzymes which are fundamentally important sources of organic radicals to initiate diverse radical reactions. Recently a bio-organometallic intermediate (Ω) that contains an Fe‒C bond has been characterized and shown to be a common feature of radical SAM enzymes. The strength of Fe‒C bond in Ω has been computed using broken-symmetry density functional theory (BS‒DFT). Additionally, Fe‒C bond dissociation energy (BDE) in Ω has been compared to that …

Aspects Of Stochastic Geometric Mechanics In Molecular Biophysics, David Frost

All Dissertations

In confocal single-molecule FRET experiments, the joint distribution of FRET efficiency and donor lifetime distribution can reveal underlying molecular conformational dynamics via deviation from their theoretical Forster relationship. This shift is referred to as a dynamic shift. In this study, we investigate the influence of the free energy landscape in protein conformational dynamics on the dynamic shift by simulation of the associated continuum reaction coordinate Langevin dynamics, yielding a deeper understanding of the dynamic and structural information in the joint FRET efficiency and donor lifetime distribution. We develop novel Langevin models for the dye linker dynamics, including rotational dynamics, based …

Understanding The Interaction Of Environmental Contaminants With Polystyrene Nanoparticles And Dna Using Nuclear Magnetic Resonance Spectroscopy And Density Functional Theory, Saduni Arachchi

All Dissertations

The objective of the thesis is to study the effect of environmental pollutants on polystyrene nanoparticles and biomolecules. This is done in two different techniques, particularly NMR and density functional theory. In this thesis, we use a combination of 1H NMR, Saturation-Transfer Difference (STD) NMR and relaxation experiments to study the interactions, kinetics and dynamics of antibiotics with polystyrene nanoparticles. (PS NPs) Density functional theory (DFT) is used to study the binding of commonly used non-oxidative hair dyes to biomolecules (DNA and amino acids) and PS particles.