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Articles 3211 - 3240 of 34537

Full-Text Articles in Physical Sciences and Mathematics

Development Of Fluorescence Based Approaches To Understand Astrocyte Biology In The Context Of Nicotine And Nicotinic Receptor Activity, Surya P. Aryal Jan 2022

Development Of Fluorescence Based Approaches To Understand Astrocyte Biology In The Context Of Nicotine And Nicotinic Receptor Activity, Surya P. Aryal

Theses and Dissertations--Chemistry

Smoking and tobacco use (STU) is a major global health problem and worldwide more than six million people die due to tobacco related diseases each year. Although majority of smokers try to quit smoking several times in their life, traditional therapeutic approaches, which focus only on neuronal cells, have a very low success rate. Understanding the effect of nicotine on glial cells, synaptic communication and blood vasculature in the brain can provide further insights on the neurobiology of substance abuse and can potentially help to design better therapeutic approaches. Glial cells are non-excitable cells in the brain which do not …

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Spatial Geochemical Changes In Central And East Texas Soils Over Time Resulting From Human Decomposition, Isabela Marisol Overturf Jan 2022

Spatial Geochemical Changes In Central And East Texas Soils Over Time Resulting From Human Decomposition, Isabela Marisol Overturf

CMC Senior Theses

Human decomposition is studied to aid forensic investigations and better understand the impact of cemeteries on urban resources like soil and groundwater. The purpose of this study was to identify changes in soil geochemistry at and around a human grave to search for lateral nutrient movement and possibly identify new patterns in elemental concentrations that could be used in estimating post-mortem intervals (PMIs). At the Forensic Anthropology Research Facility (FARF) at Texas State San Marcos, soil samples were collected from a shallow grave over the course of 54 days to conduct analysis for organic matter content, texture, pH, and bulk …

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A Spectrophotometric Determination Of Barium Complexation With Methylthymol Blue, Wesley Alexander Jan 2022

A Spectrophotometric Determination Of Barium Complexation With Methylthymol Blue, Wesley Alexander

Browse all Theses and Dissertations

In this work, a spectrophotometric titration of methylthymol blue (MTB) with barium chloride was performed at pH = 7.5, 9.6, and 12.2 to determine the stoichiometry of complexation between the two as well as formation constants and absorptivity coefficients. Complexes of 1:1, 2:1, and 3:1 Ba:MTB were suggested by the experimental data upon fitting with appropriate models using Beer’s Law. The molar absorptivities of free MTB species at 605 nm were determined to be ����2������4− = 5.0 (± 0.2) x 103 L·mol-1·cm-1, ����������5− = 7.3 (± 0.3) x 103 L·mol-1·cm-1, ��������6− = 1.3 (± 0.2) x 104 L·mol-1·cm-1. At pH …

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Estimation Of The Amount Of Active Pharmaceutical Ingredient In Over-The-Counter Available Aspirin Formulations Using Titrimetry, Uv-Visible Spectrophotometry And Raman Spectroscopy, Harismranjeet K. Chahal Jan 2022

Estimation Of The Amount Of Active Pharmaceutical Ingredient In Over-The-Counter Available Aspirin Formulations Using Titrimetry, Uv-Visible Spectrophotometry And Raman Spectroscopy, Harismranjeet K. Chahal

Browse all Theses and Dissertations

Counterfeit pharmaceuticals are a serious threat to public safety worldwide. Adverse health effects including resistance to treatment and death have resulted from the consumption of such medicines. Aspirin, which is a non-steroidal anti-inflammatory drug, has been counterfeited in the past due to its increasing demand. Rapid and easy analytical methods are needed to detect these counterfeit medicines and put a halt to the growing number of such incidents. In this study, quantitative estimation of active pharmaceutical ingredient (API) content in different over-the-counter available aspirin tablets was done using titrimetry and UV- Visible spectrophotometry. Qualitative analysis was done using Raman spectroscopy. …

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Synthesis Of Β,Β-Disubstituted Styrenes Via Trimethylsilyl Trifluoromethanesulfonate-Promoted Aldehyde-Aldehyde Aldol Addition-Deformylative Elimination., Grant J. Dixon, Michael R. Rodriguez, Tyler G. Chong, Kevin Y. Kim, C. Wade Downey Jan 2022

Synthesis Of Β,Β-Disubstituted Styrenes Via Trimethylsilyl Trifluoromethanesulfonate-Promoted Aldehyde-Aldehyde Aldol Addition-Deformylative Elimination., Grant J. Dixon, Michael R. Rodriguez, Tyler G. Chong, Kevin Y. Kim, C. Wade Downey

Chemistry Faculty Publications

In the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf) and 2,6-lutidine, α,α-disubstituted aldehydes condense with electron-rich aromatic aldehydes to yield β, β- disubstituted styrenes. More electron-rich aromatic aldehydes react more rapidly and in higher yield. Preliminary results suggest that the reaction may proceed via the ionization and formal deformylation of an aldol intermediate.

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On The Stratospheric Chemistry Of Midlatitude Wildfire Smoke, Susan Soloman, Kimberlee Dube, Kane Stone, Pengfei Yu, Doug Kinnison, Owen B. Toon, Susan E. Strahan, Karen H. Rosenlof, Robert Portmann, Sean Davis, William Randel, Peter Bernath, Chris Boone, Charles G. Bardeen, Adam Bourassa, Daniel Zawada, Doug Degenstein Jan 2022

On The Stratospheric Chemistry Of Midlatitude Wildfire Smoke, Susan Soloman, Kimberlee Dube, Kane Stone, Pengfei Yu, Doug Kinnison, Owen B. Toon, Susan E. Strahan, Karen H. Rosenlof, Robert Portmann, Sean Davis, William Randel, Peter Bernath, Chris Boone, Charles G. Bardeen, Adam Bourassa, Daniel Zawada, Doug Degenstein

Chemistry & Biochemistry Faculty Publications

Massive Australian wildfires lofted smoke directly into the stratosphere in the austral summer of 2019/20. The smoke led to increases in optical extinction throughout the midlatitudes of the southern hemisphere that rivalled substantial volcanic perturbations. Previous studies have assumed that the smoke became coated with sulfuric acid and water and would deplete the ozone layer through heterogeneous chemistry on those surfaces, as is routinely observed following volcanic enhancements of the stratospheric sulfate layer. Here, observations of extinction and reactive nitrogen species from multiple independent satellites that sampled the smoke region are compared to one another and to model calculations. The …

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Poly(Β-Gal-Thr): A New Scalable Synthetic Mucin, Manuel A. Lema Jan 2022

Poly(Β-Gal-Thr): A New Scalable Synthetic Mucin, Manuel A. Lema

Dissertations and Theses

A method for the preparation of glycosylated polypeptides via the nucleophilic ring-opening polymerization of a glycosylated N-carboxyanhydride (NCA) monomer is reported. The synthesis of 2,3,4,6-tetraacetyl-β-galactose-threonine N-carboxyanhydride (β-AcO-Gal-Thr-NCA) monomer in 5 steps with an 8 % overall yield is described, and the single-crystal X-ray structure is provided. The effect of a series of Ni0-based organometallic initiators, nucleophilic amine initiators, co-catalysts, and solvents on the polymerization were explored. The kinetics of the three most promising conditions were studied in greater detail. The conditions that provided the highest yield, low polydispersity (Ð), and …

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Pascoite Minerals And Potential Application Of Nmr Spectroscopy, Craig C. Mclauchlan, Beth Trent-Ringer, Debbie C. Crans Jan 2022

Pascoite Minerals And Potential Application Of Nmr Spectroscopy, Craig C. Mclauchlan, Beth Trent-Ringer, Debbie C. Crans

Faculty Publications – Chemistry

The 20 minerals encompassing the pascoite family of decavanadate isopolyanion-containing [V10O28]6− minerals include a few minerals, such as rakovanite, that have been described as containing a protonated decavanadate anion. Rakovanite was originally assigned the formula Na3[H3V10O28]•15H2O and now is redefined with an ideal formula (NH4)3Na3[V10O28]•12H2O. Nuclear magnetic resonance (NMR) and particularly 51V NMR spectroscopy is an informative method used to describe the protonation state and speciation in both solid and solution states …

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Synthesis And Characterization Of Ruthenium Complexes And Their Potential And Photosensitizers For Photodynamic Therapy, Keit Dine Jan 2022

Synthesis And Characterization Of Ruthenium Complexes And Their Potential And Photosensitizers For Photodynamic Therapy, Keit Dine

Master's Theses

Cancer is one of the leading causes of death in the world with over 10 million people dying of the disease every year. Inorganic complexes supported by platinum metal centers are often used in cancer treatment. However, these complexes lack selectivity for tumor cells. As such, other alternatives to platinum have been explored. Ruthenium (Ru) complexes are one of the most promising candidates due to their ability to be used as photosensitizing drugs in photodynamic therapy. Herein, we report the design, synthesis, and characterization of two novel ruthenium-based complexes. One compound is a Ru(II) homoleptic complex, while the other is …

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Electrochemical Impedance Spectroscopy Analysis Of Corrosion Of Reinforcing Steel In Fly Ash Mortar By Means Of Transmission Line Modeling, Padraig Stack Jan 2022

Electrochemical Impedance Spectroscopy Analysis Of Corrosion Of Reinforcing Steel In Fly Ash Mortar By Means Of Transmission Line Modeling, Padraig Stack

Williams Honors College, Honors Research Projects

Electrochemical impedance spectroscopy (EIS) is an important non-destructive tool that allows for a deeper understanding of the electrochemical processes and mechanisms occurring in an electrochemical cell. Equivalent electrical circuits (EECs) are used to model the impedance data into electrical components, such as resistors and capacitors, on a circuit. Current potentiostat offers software packages that can analyze the frequency response, but the software only supports “simple” EEC that can be written as fixed electrical components in some combination of series and parallel. Park and Macdonald propose a transmission line model (TLM) that does not use lumped-element models, instead, the values of …

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Synthesis Of Rna Nucleotides Under Probable Prebiotic Conditions, Ryan Stimson Jan 2022

Synthesis Of Rna Nucleotides Under Probable Prebiotic Conditions, Ryan Stimson

Williams Honors College, Honors Research Projects

RNA being composed of multiple covalently linked nucleotides is thought to have been a precursor to life circa 4.3-3.8 billion years ago. Non-enzymatically formed adenosine monophosphate (AMP), more specifically, is a vitally important subtopic of the self-assembly of the first RNA sequence. The goal of this study was to synthesize AMP non-enzymatically under benign conditions that are likely to have existed on early Earth. In this experiment, 3’,5’-cAMP was successfully formed using wet-dry cycles at 80°C paired with the minerals zeolite beta, hydroxyapatite, and aerosil 300 in the presence of adenosine, urea, and pyrophosphate. A nuclear magnetic resonance spectrometer was …

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Fluorometric Determination Of Ornidazole By Using Bsa Coated Copper Nanoclusters As A Novel Turn Off Sensor, Mehmetcan Bi̇lkay, Hayri̇ye Eda Şatana Kara Jan 2022

Fluorometric Determination Of Ornidazole By Using Bsa Coated Copper Nanoclusters As A Novel Turn Off Sensor, Mehmetcan Bi̇lkay, Hayri̇ye Eda Şatana Kara

Turkish Journal of Chemistry

A fluorescent probe based on bovine serum albumin stabilized copper nanoclusters (BSA-CuNCs) was developed for the selective and sensitive determination of ornidazole (ORN). The nanoclusters were synthesized via a one-pot hydrothermal process in basic media. The synthesized and characterized BSA-CuNCs have less than 3 nm particle size and exhibited blue emission at 405 nm when excited at 325 nm. Synthesized and characterized nanoclusters were successfully applied as a turn-off fluorescent probe for the determination of ORN in pharmaceutical dosage forms. The quenching mechanism created an was inner filter effect (IFE). The method was linear in the concentration range of 0.52-13.56 …

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A Bodipy Based Probe For The Reversible "Turn On" Detection Of Au(Iii) Ions, Muhammed Üçüncü Jan 2022

A Bodipy Based Probe For The Reversible "Turn On" Detection Of Au(Iii) Ions, Muhammed Üçüncü

Turkish Journal of Chemistry

A new "turn on" fluorescent probe for the rapid and selective detection of Au3+ ions over other metal ions was developed. The probe design was constructed on a BODIPY-2-aminopyridine skeleton showing a weak fluorescence emission signal which increased substantially after the coordination of Au3+ ions. The probe displayed remarkable sensing performances such as a low limit of detection (17 nM), a short response time (

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Chromatography-Mass Spectroscopy Analysis Of Native American Pottery For Maple Syrup Residues, Alexis Wirtz Jan 2022

Chromatography-Mass Spectroscopy Analysis Of Native American Pottery For Maple Syrup Residues, Alexis Wirtz

Honors Program Theses

The research conducted regards whether or not Native Americans understood how to create maple syrup before the influence of Europeans. The analytical technique that was used is gas chromatography-mass spectrometry (GC-MS). This technique assisted in understanding what organic residues resided within the pottery and what those organic residues tell us about Native American history. An analysis of organic residues was performed on the following types of pottery: proof of concept pottery, weathered pottery (an analog of the proof of concept), and Native American pottery. The residues used in analysis were obtained through the usage of different solvent systems - Acetone: …

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Unique Features Of Alarmone Metabolism In Clostridioides Difficile, Asia Poudel, Astha Pokhrel, Adenrele Oludiran, Estevan J. Coronado, Kwincy Alleyne, Marrett M. Gilfus, Raj K. Gurung, Surya B. Adhikari, Erin B. Purcell Jan 2022

Unique Features Of Alarmone Metabolism In Clostridioides Difficile, Asia Poudel, Astha Pokhrel, Adenrele Oludiran, Estevan J. Coronado, Kwincy Alleyne, Marrett M. Gilfus, Raj K. Gurung, Surya B. Adhikari, Erin B. Purcell

Chemistry & Biochemistry Faculty Publications

The “magic spot” alarmones (pp)pGpp, previously implicated in Clostridioides difficile antibiotic survival, are synthesized by the RelA-SpoT homolog (RSH) of C. difficile (RSHCd) and RelQCd. These enzymes are transcriptionally activated by diverse environmental stresses. RSHCd has previously been reported to synthesize ppGpp, but in this study, we found that both clostridial enzymes exclusively synthesize pGpp. While direct synthesis of pGpp from a GMP substrate, and (p)ppGpp hydrolysis into pGpp by NUDIX hydrolases, have previously been reported, there is no precedent for a bacterium synthesizing pGpp exclusively. Hydrolysis of the 5′ phosphate or pyrophosphate from GDP …

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The Acute Physiological Response Of Polar Bears To Helicopter Capture, John P. Whiteman, Henry J. Harlow, George M. Durner, Eric V. Regehr, Steven C. Amstrup, Anthony M. Pagano, Merav Ben-David Jan 2022

The Acute Physiological Response Of Polar Bears To Helicopter Capture, John P. Whiteman, Henry J. Harlow, George M. Durner, Eric V. Regehr, Steven C. Amstrup, Anthony M. Pagano, Merav Ben-David

Biological Sciences Faculty Publications

Many wildlife species are live captured, sampled, and released; for polar bears (Ursus maritimus) capture often requires chemical immobilization via helicopter darting. Polar bears reduce their activity for approximately 4 days after capture, likely reflecting stress recovery. To better understand this stress, we quantified polar bear activity (via collar‐mounted accelerometers) and body temperature (via loggers in the body core [Tabd] and periphery [Tper]) during 2–6 months of natural behavior, and during helicopter recapture and immobilization. Recapture induced bouts of peak activity higher than those that occurred during natural behavior for 2 of 5 bears, …

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Advancing Competency In Managing Risk And Knowledge: Steps Toward Operationalisation Of The Risk-Knowledge Infinity Cycle (Rki Cycle) - Part 1: Improving Effectiveness Of Risk-Based Decision Making (Rbdm), Martin Lipa, Paige Kane, Anne Greene Jan 2022

Advancing Competency In Managing Risk And Knowledge: Steps Toward Operationalisation Of The Risk-Knowledge Infinity Cycle (Rki Cycle) - Part 1: Improving Effectiveness Of Risk-Based Decision Making (Rbdm), Martin Lipa, Paige Kane, Anne Greene

Articles

To date, literature on the Risk-Knowledge Infinity Cycle (RKI Cycle) has mainly been theoretical. This paper series intent is to focus on the operationalisation of the RKI Cycle by describing a series of steps – the “How to” – for RKI Cycle deployment, to help move the RKI Cycle from theory to practice. The first paper in this series focuses on how the RKI Cycle can support effective Risk-Based Decision Making (RBDM).

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First Long-Time Airborne Fungal Spores Study In Dublin, Ireland (1978–1980), Moisés Martínez-Bracero, Emma Markey, Jerry Hourihane Clancy, John Sodeau, David J. O'Connor Jan 2022

First Long-Time Airborne Fungal Spores Study In Dublin, Ireland (1978–1980), Moisés Martínez-Bracero, Emma Markey, Jerry Hourihane Clancy, John Sodeau, David J. O'Connor

Articles

Ambient fungal spores within the atmosphere can contribute to a range of negative human, animal and plant health conditions and diseases. However, trends in fungal spore seasonality, species prevalence, and geographical origin have been significantly understudied in Ireland. Previously unpublished data from the late 1970s have recently been collected and analysed to establish historical fungal spore trends/characteristics for Dublin. Historical spore concentrations were largely dominated by Alternaria, Ascospores, Basidiospores, Botrytis, Cladosporium, Erysiphe and Rusts. The main fungal spore season for Dublin commenced in April with the fructification of Scopulariopsis and Ganoderma. However, the vast majority of other spore types did …

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Copper(Ii) And Silver(I)‑1,10‑Phenanthroline‑5,6‑Dione Complexes Interact With Double‑Stranded Dna: Further Evidence Of Their Apparent Multi‑Modal Activity Towards Pseudomonas Aeruginosa, Anna Clara Milesi Galdino, Lívia Viganor, Matheus Mendonça Pereira, Michael Devereux, Malachy Mccann, Marta Helena Branquinha, Zara Molphy, Sinéad O'Carroll, Conor Bain, Georgia Menounou, Andrew Kellett, André Luis Souza Dos Santos Jan 2022

Copper(Ii) And Silver(I)‑1,10‑Phenanthroline‑5,6‑Dione Complexes Interact With Double‑Stranded Dna: Further Evidence Of Their Apparent Multi‑Modal Activity Towards Pseudomonas Aeruginosa, Anna Clara Milesi Galdino, Lívia Viganor, Matheus Mendonça Pereira, Michael Devereux, Malachy Mccann, Marta Helena Branquinha, Zara Molphy, Sinéad O'Carroll, Conor Bain, Georgia Menounou, Andrew Kellett, André Luis Souza Dos Santos

Articles

Tackling microbial resistance requires continuous efforts for the development of new molecules with novel mechanisms of action and potent antimicrobial activity. Our group has previously identified metal-based compounds, [Ag(1,10-phenanthroline-5,6-dione)2]ClO4 (Ag-phendione) and [Cu(1,10-phenanthroline-5,6-dione)3](ClO4)2.4H2O (Cu-phendione), with efficient antimicrobial action against multidrug-resistant species. Herein, we investigated the ability of Ag-phendione and Cu-phendione to bind with double-stranded DNA using a combination of in silico and in vitro approaches. Molecular docking revealed that both phendione derivatives can interact with the DNA by hydrogen bonding, hydrophobic and electrostatic interactions. Cu-phendione exhibited the highest binding affinity to either major (− 7.9 kcal/mol) or minor (− 7.2 kcal/mol) …

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Exploring The Potential Of Water-Soluble Cu(Ii) Complexes With Mpa–Cdte Quantum Dots For Photoinduced Electron Transfer, Niharika Krishna Botcha, Rithvik R. Gutha, Seyed M. Sadeghi, Anusree Mukherjee Jan 2022

Exploring The Potential Of Water-Soluble Cu(Ii) Complexes With Mpa–Cdte Quantum Dots For Photoinduced Electron Transfer, Niharika Krishna Botcha, Rithvik R. Gutha, Seyed M. Sadeghi, Anusree Mukherjee

Research, Publications & Creative Work

Three water-soluble copper complexes based on the amine/pyridine functionalities were investigated, along with quantum dots, as a catalyst–photosensitizer assembly, respectively, for fundamental understanding of photoinduced electron transfer. Luminescence quenching and lifetime measurements were performed to try and establish the actual process that leads to the quenching, such as electron transfer, energy transfer, or complex formation (static quenching). Cyclic voltammetry and dynamic light scattering experiments were also performed. Irrespective of the similar reduction potentials of the three complexes, very different photoluminescence properties were observed.

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The Influence Of Hydrogen Peroxide On The Enrichment Of Fe(Iii) Reducing Bacteria From Acid Mine Drainage, Susami Seth Jan 2022

The Influence Of Hydrogen Peroxide On The Enrichment Of Fe(Iii) Reducing Bacteria From Acid Mine Drainage, Susami Seth

Williams Honors College, Honors Research Projects

It is hypothesized that the ocean of Europa, a Jupiter moon, hosts bacteria on its oceanic floor. Understanding how Fe(III) reducing bacteria (FeRB) from AMD utilize organic materials within its surrounding environment outlines how FeRB could thrive and tolerate extreme conditions. FeRB are known to tolerate metals and highly reactive oxidants species (ROS), but in this experiment, H2O2 was the experimental factor to further test FeRB tolerance. H2O2 is a common ROS and is damaging to living material such as proteins, DNA, and RNA. A range of H2O2 concentrations were fed …

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Biomimetic Synthesis Of Palladium Nanoparticles For Catalytic Application, Emily A. Groover Jan 2022

Biomimetic Synthesis Of Palladium Nanoparticles For Catalytic Application, Emily A. Groover

Electronic Theses and Dissertations

The synthesis of palladium nanoparticles (Pd NPs) using materials-directed peptides is a novel, nontoxic approach which exerts a high level of control over the particle size and shape. This biomimetic technique is environmentally benign, featuring nonhazardous ligands and ambient conditions. Nanoparticles are extremely reactive catalysts, boasting a large surface-to-volume ratio when compared to their bulk counterparts. The rational design of these nanoparticles using peptides has been very successful in aqueous environments, but no research has been done to apply it in organic systems. As such, the biomimetic synthesis of Pd NPs in an organic system is here investigated, with ethanol …

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Molybdenum Oxide/Antimony Nanobelts Embedded In Asymmetric Membranes For Use As High-Capacity Lithium/Sodium-Ion Battery Anodes, Logan Williams Jan 2022

Molybdenum Oxide/Antimony Nanobelts Embedded In Asymmetric Membranes For Use As High-Capacity Lithium/Sodium-Ion Battery Anodes, Logan Williams

Electronic Theses and Dissertations

Lithium-ion batteries (LIB) are a key aspect of our daily lives, from smartphones to electric vehicles. Commercially available LIB use graphite anodes due to their reliability and safety. Graphite anodes present one key disadvantage: a relatively low theoretical capacity of 372 mAh g-1. It is of great importance that new research focuses on high-capacity anode materials to further our sustainability and usage of LIB. While increasing the performance of LIB is of great interest, developing alternative energy storage devices is gaining attention in academia and industry R&D. Sodium has become a topic of interest in recent years due to sodium’s …

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Investigation Of Intramolecular And Intermolecular Aza-Michael Reactions, Nadia Z. Singleton Jan 2022

Investigation Of Intramolecular And Intermolecular Aza-Michael Reactions, Nadia Z. Singleton

Electronic Theses and Dissertations

The hydroamination of dimaleimides with diamines has been accomplished to access novel polymers. Various dimaleamides and dimaleimides were synthesized from commercially available diamines and maleic anhydride. The resulting dimaleamides were then ring-closed to their respective dimaleimides either directly in the presence of acid or via the synthesis of mixed amide-esters which then ring close in the presence of acid under heat. Hydroamination of the dimaleimides with piperazine was accomplished in bulk at room temperature. The reaction is spontaneous thus leading to the formation of polyimides with high functional group conversion within minutes. The kinetics of the maleamides and maleimides was …

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Polymer Based Advanced Recipes For Imidazoles: A Review, Shivnath Patel, Rajendra Patil, Jagdish Chavan, Anil Beldar Jan 2022

Polymer Based Advanced Recipes For Imidazoles: A Review, Shivnath Patel, Rajendra Patil, Jagdish Chavan, Anil Beldar

Turkish Journal of Chemistry

Imidazoles and their scaffold are an extraordinarily essential class of nitrogen bearing azole heterocyclic compounds. They have different place in wide area of organic synthesis, which can be utilized in a variety of applications in diverse fields including agriculture, medicine, polymer and various industries. Numerous methods for synthesis of imidazole derivatives are reported in last few decades. Existing conventional methods are more or less significant and confined due to its time-consuming reactions, high cost of catalyst, extensive methodologies, low yield rate or no reusability respectively. Overcoming to inefficient conventional methods, finding of novel and effective methods of imidazole synthesis becomes …

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Synthesis Of Some New Isoxazole Compounds And Their Biological Tyrosinase And Antioxidant Activities, Seda Fandakli Jan 2022

Synthesis Of Some New Isoxazole Compounds And Their Biological Tyrosinase And Antioxidant Activities, Seda Fandakli

Turkish Journal of Chemistry

In this study, 7 new isoxazole compounds (8-14) were synthesized from the cyclization of chalcone compounds (1-7) containing different functional groups with hydroxylamine hydrochloride in alkaline medium. Tyrosinase and antioxidant properties of 8-14 were investigated. IC50 values for the tyrosinase enzyme inhibition of compounds 8, 11, 12, and 13 were varied between 61.47 ± 3.46 and 188.52 ± 5.85, while compounds 9, 10 and 14 did not show any inhibition effect. The antioxidant properties of 8-14 were investigated by DPPH and CUPRAC methods. Compound 12 showed the best DPPH radical scavenging activity (SC50: 40.21 ± 2.71), while 12 and 13 …

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Synthesis And In Vitro Α-Glucosidase And Cholinesterases Inhibitory Actions Of Watersolublemetallophthalocyanines Bearing ({6-[3-(Diethylamino)Phenoxy]Hexyl}Oxy Groups, Turgut Keleş, Zekeri̇ya Biyiklioğlu, Di̇dem Akkaya, Arzu Özel, Burak Barut Jan 2022

Synthesis And In Vitro Α-Glucosidase And Cholinesterases Inhibitory Actions Of Watersolublemetallophthalocyanines Bearing ({6-[3-(Diethylamino)Phenoxy]Hexyl}Oxy Groups, Turgut Keleş, Zekeri̇ya Biyiklioğlu, Di̇dem Akkaya, Arzu Özel, Burak Barut

Turkish Journal of Chemistry

In this paper, we have prepared peripherally tetra-({6-[3-(diethylamino)phenoxy]hexyl}oxy substituted cobalt(II), copper(II), manganese(III) phthalocyanines (3, 4, 5) and their water-soluble derivatives (3a, 4a, 5a). Then, in vitro α-glucosidase and cholinesterases inhibitory actions of the water-soluble 3a, 4a, 5a were examined using spectrophotometric methods. 4a had the highest inhibitory effects among the tested compounds against α-glucosidase due to IC50 values. 4a and 5a had 40 fold higher inhibitory effects than the positive control. For cholinesterases, the compounds showed significant inhibitory actions that of galantamine which was used as a positive control. According to the SI value, 3a inhibited acetylcholinesterase enzyme selectively. In …

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Ferrihydrite/Ultrasound Activated Peroxymonosulfate For Humic Acid Removal, Hang Yang, Yi Zhang, Shibin Xia Jan 2022

Ferrihydrite/Ultrasound Activated Peroxymonosulfate For Humic Acid Removal, Hang Yang, Yi Zhang, Shibin Xia

Turkish Journal of Chemistry

In this study, ferrihydrite/ultrasound (US) system was used to activate peroxymonosulfate (PMS) to treat humic acid (HA) in artificial aqueous. The physical and chemical properties of ferrihydrite were characterized using SEM, zeta potential, BET, XRD, FTIR, and XPS analysis. A series of experiments were conducted to evaluate the effect of various factor on HA removal, including dosage of ferrihydrite, PMS concentration and pH value. The combination uses of US and ferrihydrite had obvious synergistic effect for HA removal. Under ferrihydrite/US/PMS system, nonthermal effect of US played the main role for HA removal. According to the result of radical quenching experiment, …

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Synthesis, Antioxidant Activity, Molecular Docking And Adme Studies Of Novel Pyrrolebenzimidazolederivatives, Fi̇kri̇ye Zengi̇n Karadayi, Rahman Başaran, Mehmet Murat Kişla, Bi̇nay Eke, Zeynep Alagöz Jan 2022

Synthesis, Antioxidant Activity, Molecular Docking And Adme Studies Of Novel Pyrrolebenzimidazolederivatives, Fi̇kri̇ye Zengi̇n Karadayi, Rahman Başaran, Mehmet Murat Kişla, Bi̇nay Eke, Zeynep Alagöz

Turkish Journal of Chemistry

Several 5-(alkylsulfonyl)-1-substituted-2-(1H-pyrrol-2-yl)-1H-benzo[d]imidazole derivatives were synthesized and their antioxidant activities were investigated using lipid peroxidation (LPO) and 7-ethoxyresorufin O-deethylase (EROD) assays. Docking analysis with Human NAD[P]H-Quinone oxidoreductase 1 (NQO1) was also performed to gather thorough information about these compounds that have antioxidant activities. Moreover, their molecular descriptors and ADME properties were calculated using the SwissADME online program. As a result, most of our compounds possessed better affinity and created ample interactions with NQO1. The most potent compound 5j had LP inhibition value of 3.73 nmol/mg/min. Other compounds exhibited moderate activity on LP levels comparing to standard butylated hydroxy toluene (BHT). However, …

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Development And Validation Of A New Rp-Hplc Method For Organic Explosive Compounds, Sali̇h Murat Ünsal, Emre Erkan Jan 2022

Development And Validation Of A New Rp-Hplc Method For Organic Explosive Compounds, Sali̇h Murat Ünsal, Emre Erkan

Turkish Journal of Chemistry

A new RP-HPLC method was developed and validated to achieve the separation and quantification of the organic explosive compounds such as pentaerythritol tetranitrate (PETN), 1-methyl-2,4,6-trinitro toluen (TNT), picric acid, 1,3,5,7-tetrazocine (HMX), cyclorimethylenetrinitramine (RDX), 2,4,6 Tri nitro phenyl methyl nitramine (Tetryl), 1-methyl-2,4-dinitro toluen (DNT), ethylene glycol dinitrate (EGDN), and trinitroglycerine (TNG) in this study. The mobile phase composition (IPA percentage in water) and the flow rate was optimized for the separation of the organic explosive compounds. Theoretical plate number (N), capacity factor (k'), resolution (Rs) were used to determine the optimum chromatographic conditions. The most favorable conditions were detected as 22% …

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