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Assessing Affective Differences Between A Virtual General Chemistry Experiment And A Similar Hands-On Experiment, Cory Hensen, Jack Barbera Aug 2019

Assessing Affective Differences Between A Virtual General Chemistry Experiment And A Similar Hands-On Experiment, Cory Hensen, Jack Barbera

Chemistry Faculty Publications and Presentations

To date, few general chemistry laboratory studies have included affective measures despite calls for more research on aspects of this domain. This shortage of studies may be partially due to the scarcity of affective measures that have been designed for, or tested in, the college laboratory setting. To provide measures for use in this environment, several existing affective scales were adapted for this new context. Before data from the scales were utilized to study the environment, evidence was provided for the validity and reliability of the data generated from them. Once sufficient evidence was provided, it was possible to determine …


Development And Evaluation Of A Hybrid Adi/Swh Model Pre-Laboratory Curriculum, Tabitha Alitz, Dawn Del Carlo Aug 2019

Development And Evaluation Of A Hybrid Adi/Swh Model Pre-Laboratory Curriculum, Tabitha Alitz, Dawn Del Carlo

Summer Undergraduate Research Program (SURP) Symposium

Previous Research:
• Students value each part of the pre-lab differently, struggle to connect all of the components, and therefore fail to see the big picture
• Students find the pre-lab moderately helpful in understanding both the concepts and mechanics of the lab, but find it less helpful at the end of the semester compared to beginning
• The cognitive load demands of the SWH pre-lab hinders students’ ability to participate in authentic scientific inquiry


Computational Studies Of High-Oxidation State Main-Group Metal Hydrocarbon C-H Functionalization, Clinton R. King Aug 2019

Computational Studies Of High-Oxidation State Main-Group Metal Hydrocarbon C-H Functionalization, Clinton R. King

Theses and Dissertations

High-oxidation state main-group metal complexes are potential alternatives to transition metals for electrophilic C-H functionalization reactions. However, there is little known about how selection of the p-block, main-group metal and ligand impact C-H activation and functionalization thermodynamics and reactivity. Chapter 2 reports density functional theory (DFT) calculations used to determine qualitative and quantitative features of C-H activation and metal-methyl functionalization energy landscapes for reaction between high-oxidation state d10s0 InIII, TlIII, SnIV, and PbIV carboxylate complexes with methane. While the main-group metal influences the C-H activation barrier height in a periodic manner, the carboxylate ligand has a much larger quantitative impact …


Two Cretaceous Tales Of The Land And The Sea, Puloma Chakrabarty May 2019

Two Cretaceous Tales Of The Land And The Sea, Puloma Chakrabarty

Earth & Environmental Sciences Dissertations - Archive

The Cretaceous Period (145-66 Ma), with no magnetic reversal for ~79 Ma, is generally termed as the Cretaceous Normal Superchron or the Magnetic Quiet Zone. There is evidence of at least two major large scale, global volcanisms in this long period synchronous with mass extinctions, during the Late Cretaceous and at the end of the Cretaceous. This study focusses on the effect of these two global volcanisms on 1. The Ocean: Eagle Ford, South Texas at the beginning of the Late Cretaceous, 93.9 Ma, probably caused by Cretaceous mafic volcanism from the Ontong Java Plateau and/or Caribbean Large Igneous Province …


Studies On Regulation Of Dihydrotestosterone Binding To And Releasing From The Androgen Receptor, Tahyra M. Resto Santos May 2019

Studies On Regulation Of Dihydrotestosterone Binding To And Releasing From The Androgen Receptor, Tahyra M. Resto Santos

Theses and Dissertations

The androgen receptor (AR) is a nuclear receptor that responds to testosterone and 5α-dihydrotestosterone (DHT) by modulating gene expression in a variety of cells, including prostate and muscle tissues. Studies of small molecule interaction with AR have shown diphenyl compounds inhibiting through a binding site labeled Binding Function 3 (BF3). The goal of this research is to analyze the interaction of the BF3 site with DDT and related compounds. Amino acids that are exposed on the surface of the BF3 that might interact with different compounds were mutated. Mutant proteins were tested experimentally for their impact on the inhibition the …


Design And Synthesis Of Simplified Analogs Of The Natural Product Sordarin As Potential Antifungal Agents, Yibiao Wu Apr 2019

Design And Synthesis Of Simplified Analogs Of The Natural Product Sordarin As Potential Antifungal Agents, Yibiao Wu

Dissertations (1934 -)

Invasive fungal infection is a life-threatening illness that causes high mortality, and is especially common among patients with compromised immune systems. However, currently there are only three major classes of clinically useful drugs capable of treating such infections. In addition, due to the fact that drug resistance has become a serious issue especially among patients who suffer from chronic infections, it is urgent to identify new drug candidates, particular those of new classes. The discovery of the natural product sordarin and its novel mechanism of action of inhibiting fungal protein synthesis via the fungal eukaryotic elongation factor 2 (eEF2) led …


We Are All Alive: Understanding Connections Between People And Coral Reefs In Samoa, Kalamakaleimahoehoe Porter Apr 2019

We Are All Alive: Understanding Connections Between People And Coral Reefs In Samoa, Kalamakaleimahoehoe Porter

Independent Study Project (ISP) Collection

This work seeks to incorporate ecological research methods, socioeconomic data analysis, and local story collection into one understanding of coral reefs on the island of Upolu in Samoa. Data collection utilized transects and timed dives to assess four reef health indicators, and socio-economic indicators were sourced from the Samoa Bureau of Statistics. Interviews were also conducted to gain Samoan perspectives on the importance of coral reefs. Findings include patterns between the socioeconomic factors of population demographics, unemployment rates, education, and improved water, waste, and sanitation facilities and the environmental indicators of prevalence of plastic, percentage cover of living coral, parrotfish …


Synthesis Of Simplified Azasordarin Analogs As Potential Antifungal Agents, Yibiao Wu, Chris Dockendorff Mar 2019

Synthesis Of Simplified Azasordarin Analogs As Potential Antifungal Agents, Yibiao Wu, Chris Dockendorff

Chemistry Faculty Research and Publications

A new series of simplified azasordarin analogs was synthesized using as key steps a Diels–Alder reaction to generate a highly substituted bicyclo[2.2.1]heptane core, followed by a subsequent nitrile alkylation. Several additional strategies were investigated for the generation of the key tertiary nitrile or aldehyde thought to be required for inhibition at the fungal protein eukaryotic elongation factor 2. This new series also features a morpholino glycone previously reported in semisynthetic sordarin derivatives with broad spectrum antifungal activity. Despite a lack of activity against Candida albicans for these early de novo analogs, the synthetic route reported here permits more comprehensive modifications …


Metrics And Methods Used To Compare Student Performance Data In Chemistry Education Research Articles, Michael R. Mack, Cory Hensen, Jack Barbera Feb 2019

Metrics And Methods Used To Compare Student Performance Data In Chemistry Education Research Articles, Michael R. Mack, Cory Hensen, Jack Barbera

Chemistry Faculty Publications and Presentations

Quasi-experiments are common in studies that estimate the effect of instructional interventions on student performance outcomes. In this type of research, the nature of the experimental design, the choice in assessment, the selection of comparison groups, and the statistical methods used to analyze the comparison data dictate the validity of causal inferences. Therefore, gathering and reporting validity evidence in causal studies is of utmost importance, especially when conclusions have real policy implications for students and faculty, among other stakeholders. This review examines 24 articles that reported quantitative investigations of the effect of instructional interventions on performance-based outcomes conducted within undergraduate …


Expansion Of An Ultracold Neutral Plasma, Yin Li Jan 2019

Expansion Of An Ultracold Neutral Plasma, Yin Li

Honors Theses

Ultracold neutral plasmas (UNP) exhibit interesting behavior and are more feasible to control than hot plasmas. Physicists would like to lower the temperature of a UNP to achieve a higher Coulomb coupling parameter, Γ for both electrons and ions. However, the three body recombination (TBR) between ions and electrons produces Rydberg atoms and heats up the plasma electrons, thereby ionizing them to Γe < 0.2. Adding Rydberg atoms to the plasma will reduce the temperature of a UNP in certain situations. In this honors project, we tried to achieve a Γe value greater than 0.5 by embedding Rydberg atoms multiple times in the plasma. We did extensive numerical simulations, but we were unable to replicate previous results from another group which obtained Γe = 0.5 in the first 1 µ s of plasma evolution. However, we were able to use the simulation results to test various different experiment scenarios. For experiments, we created a UNP of Rubidium atoms in the magneto-optical trap by laser cooling and photoionization. We figured out a nice way to zero the electric field within the field meshes by looking at the plasma expansion very late in its evolution through the micro-channel plate. We set the voltage and delay on the field mesh bias to find expansion velocity of the plasma for time t > 50 µs, and we used different methods to deduce the expansion velocity from the ion time of flight signals. However, we found that there was no relation of Γe at 1 µ s and the expansion velocity …


Variability In Groundwater Flow And Chemistry In The Houzhai Karst Basin, Guizhou Province, China, Joshua M. Barna Jan 2019

Variability In Groundwater Flow And Chemistry In The Houzhai Karst Basin, Guizhou Province, China, Joshua M. Barna

Theses and Dissertations--Earth and Environmental Sciences

Understanding how karst aquifers store and transmit water and contaminants is an ongoing problem in hydrogeology. Flowpath and recharge heterogeneity contribute to the complexity of these systems. This thesis explores karst-conduit connectivity and water chemistry variability in the Houzhai catchment in Guizhou province, China. Artificial tracer tests were conducted during both the monsoon and dry seasons to understand temporal variability in connectivity and water velocity between karst features. Multiple flowpaths through the catchment are activated during the monsoon season and partially abandoned during the dry season. Additionally, gradient reversals during monsoonal high-flow events and as a result of pumping can …


Green Chemistry In United States Science Policy, Emily Jarvis Jan 2019

Green Chemistry In United States Science Policy, Emily Jarvis

Chemistry and Biochemistry Faculty Works

Although optimizing each of the Twelve Principles of Green Chemistry is necessary for achieving the greenest possible chemistry in the lab, there are additional creative ways to promote green chemistry not encompassed by these. Communicating to society the importance of green chemistry beyond the laboratory is essential. Of course, doing this effectively presents distinct challenges to those encountered when designing chemical syntheses. Here, I discuss several observations from my time working in federal science policy as an American Association for the Advancement of Science/American Chemical Society Congressional Science Fellow in the United States Senate. I suggest a practical science policy …


Synthesis, Characterization, And Nonlinear Optical Properties Of Some New Series Of S-(5-Aryl-1,3,4-Oxadiazol-2-Yl) 2-Chloroethanethioate Derivatives, Zahra Dono Ghezelbash, Hamideh Motiei, Miri Mahmoody, Karim Akbari Delmaghani Jan 2019

Synthesis, Characterization, And Nonlinear Optical Properties Of Some New Series Of S-(5-Aryl-1,3,4-Oxadiazol-2-Yl) 2-Chloroethanethioate Derivatives, Zahra Dono Ghezelbash, Hamideh Motiei, Miri Mahmoody, Karim Akbari Delmaghani

Turkish Journal of Chemistry

In the present investigation, some novel S-(5-aryl-1,3,4-oxadiazol-2-yl)2-chloroethanethioate (3a-3e) derivatives were synthesized and their impact on optical properties was studied. They have also been characterized by elemental analysis and various spectroscopic methods including FTIR, $^{1}$H NMR, $^{13}$C NMR, and UV-Vis techniques. The nonlinear refractive indexes of 3a-3e were also measured in dichloromethane via Z-scan method using a continuous wave diode-pumped laser at 532 nm wavelength. The nonlinear refractive coefficient of compounds was obtained from ${10}^{11}\, \, {m}^{{2}}{/W}$ order. Regarding the appropriate nonlinearity of these compounds, they could be considered good candidates for biooptical and photonic applications. All the synthesized compounds (3a-3e) …


Computational Quantum Chemistry Studies Of The Interactions Of Amino Acids Side Chains With The Guanine Radical Cation., Edward Acheampong Dec 2018

Computational Quantum Chemistry Studies Of The Interactions Of Amino Acids Side Chains With The Guanine Radical Cation., Edward Acheampong

Electronic Theses and Dissertations

Guanine is generally accepted as the most easily oxidized DNA base when cells are subjected to ionizing radiation, photoionization or photosensitization. At pH 7, the midpoint reduction potential is on the order of 0.2 – 0.3 V higher than those of the radicals of e.g. tyrosine, tryptophan cysteine and histidine, so that the radical “repair” (or at least, a thermodynamically favorable reaction) involving these amino acids is feasible. Computational quantum studies have been done on tyrosine, tryptophan, cysteine and histidine side chains as they appear in histones. Density functional theory was employed using B3LYP/6-31G+ (d, p) basis set to study …


Chem 360-001 Environmental Chemistry, Alexei Khalizov Sep 2018

Chem 360-001 Environmental Chemistry, Alexei Khalizov

Chemistry, Environmental and Forensic Science Syllabi

No abstract provided.


Synthesis And Evaluation Of Densely-Functionalized Troponoids, Danielle R. Hirsch Sep 2018

Synthesis And Evaluation Of Densely-Functionalized Troponoids, Danielle R. Hirsch

Dissertations, Theses, and Capstone Projects

Herein, we document our efforts to expand the scope of troponoid synthetic methodology towards densely-substituted scaffolds. This body of work has focused primarily on an oxidopyrylium cycloaddition/ring-opening strategy for the synthesis and biochemical evaluation of troponoids for assistance in a variety of medicinal chemistry studies. In Chapter 1, we outline the use of this synthetic strategy in the profiling of a library of synthetic αHTs against an aminoglycoside antibiotic resistance enzyme known as aminoglycoside-2’’-O-nucleotidyltransferase [ANT(2’’)-Ia]. Enzymatic mechanistic insights have been gleaned from an assessment of troponoid/antibiotic synergistic potential. In particular, two synthetic constructs were identified as promising antibiotic adjuvant candidates, …


Conformationally-Controlled Late-Stage Modifications For Sar Studies Of The C-3-Glcp Moiety Of Ipomoeassin F, Lucas Whisenhunt Aug 2018

Conformationally-Controlled Late-Stage Modifications For Sar Studies Of The C-3-Glcp Moiety Of Ipomoeassin F, Lucas Whisenhunt

Graduate Theses and Dissertations

The resin glycoside, ipomoeassin F has been shown to be extremely potent against multiple cancer lines (IC50 = 4.2-36 nM). However, the mechanism of action of this potent and complex natural product is still not fully understood. The α,β-unsaturated esters of the glucosyl moiety have been shown to be vital for the overall cytotoxicity of ipomoeassin F. Nevertheless, the importance of the tigloyl ester of the glucosyl moiety is still largely unknown. This work aimed to study the pharmacophore importance of the tigloyl ester by creating, an efficient, scalable, and flexible synthesis route for various analogs. The 18-linear step synthesis …


Moving Beyond Alpha: A Primer On Alternative Sources Of Single-Administration Reliability Evidence For Quantitative Chemistry Education Research, Regis Komperda, Thomas C. Pentecost, Jack Barbera Jul 2018

Moving Beyond Alpha: A Primer On Alternative Sources Of Single-Administration Reliability Evidence For Quantitative Chemistry Education Research, Regis Komperda, Thomas C. Pentecost, Jack Barbera

Chemistry Faculty Publications and Presentations

This methodological paper examines current conceptions of reliability in chemistry education research (CER) and provides recommendations for moving beyond the current reliance on reporting coefficient alpha (α) as reliability evidence without regard to its appropriateness for the research context. To help foster a better understanding of reliability and the assumptions that underlie reliability coefficients, reliability is first described from a conceptual framework, drawing on examples from measurement in the physical sciences; then classical test theory is used to frame a discussion of how reliability evidence for psychometric measurements is commonly examined in CER, primarily in the form of single-administration reliability …


Evaluation Of Trace-Metal And Isotopic Records As Techniques For Tracking Lifetime Movement Patterns In Fishes, Jennifer E. Granneman Jul 2018

Evaluation Of Trace-Metal And Isotopic Records As Techniques For Tracking Lifetime Movement Patterns In Fishes, Jennifer E. Granneman

USF Tampa Graduate Theses and Dissertations

The focus of this work was on the use of otolith microchemistry and fish eye lens chemical profiles to measure fish movement and provided indirect support for the use of otolith microchemistry to examine exposure to crude oil. Chapter 1 provides an introduction to the applications of otolith microchemistry and eye lens isotopic profiles. In the second chapter, which examined associations between metal exposure and lesion formation in fishes collected after the Deepwater Horizon (DWH) oil spill, I did not observe any change in oil-associated metal concentrations in otoliths coinciding with the timing of the DWH oil spill. This suggests …


Deciphering The Mechanism Of O2 Reduction With Electronically Tunable Non-Heme Iron Enzyme Model Complexes, Roshaan Surendhran, Alexander A. D'Arpino, Bao Y. Sciscent, Anthony F. Cannella, Alan E. Friedman, Samantha N. Macmillan, Rupal Gupta, David C. Lacy Jun 2018

Deciphering The Mechanism Of O2 Reduction With Electronically Tunable Non-Heme Iron Enzyme Model Complexes, Roshaan Surendhran, Alexander A. D'Arpino, Bao Y. Sciscent, Anthony F. Cannella, Alan E. Friedman, Samantha N. Macmillan, Rupal Gupta, David C. Lacy

Publications and Research

A homologous series of electronically tuned 2,20,200-nitrilotris(N-arylacetamide) pre-ligands (H3LR) were prepared (R ¼ NO2, CN, CF3, F, Cl, Br, Et, Me, H, OMe, NMe2) and some of their corresponding Fe and Zn species synthesized. The iron complexes react rapidly with O2, the final products of which are diferric mu-oxo bridged species. The crystal structure of the oxidized product obtained from DMA solutions contain a structural motif found in some diiron proteins. The mechanism of iron mediated O2 reduction was explored to the extent that allowed us to construct an empirically consistent rate law. A Hammett plot was constructed that enabled …


Deconvoluting The Effects Of Surface Chemistry And Nanoscale Topography: Pseudomonas Aeruginosa Biofilm Nucleation On Si-Based Substrates, Jing Zhang, Jingling Huang, Carmen Say, Robert L. Dorit, Kate Queeney Jun 2018

Deconvoluting The Effects Of Surface Chemistry And Nanoscale Topography: Pseudomonas Aeruginosa Biofilm Nucleation On Si-Based Substrates, Jing Zhang, Jingling Huang, Carmen Say, Robert L. Dorit, Kate Queeney

Chemistry: Faculty Publications

Hypothesis

The nucleation of biofilms is known to be affected by both the chemistry and topography of the underlying substrate, particularly when topography includes nanoscale (nm) features. However, determining the role of topography vs. chemistry is complicated by concomitant variation in both as a result of typical surface modification techniques. Analyzing the behavior of biofilm-forming bacteria exposed to surfaces with systematic, independent variation of both topography and surface chemistry should allow differentiation of the two effects.

Experiments

Silicon surfaces with reproducible nanotopography were created by anisotropic etching in deoxygenated water. Surface chemistry was varied independently to create hydrophilic (OH- terminated) …


Using Quenching To Detect Corrosion On Sculptural Metalwork: A Real-World Application Of Fluorescence Spectroscopy, Cory Hensen, Tami Lasseter Clare, Jack Barbera May 2018

Using Quenching To Detect Corrosion On Sculptural Metalwork: A Real-World Application Of Fluorescence Spectroscopy, Cory Hensen, Tami Lasseter Clare, Jack Barbera

Chemistry Faculty Publications and Presentations

Fluorescence spectroscopy experiments are a frequently taught as part of upper-division teaching laboratories. To expose undergraduate students to an applied fluorescence technique, a corrosion detection method, using quenching, was adapted from authentic research for an instrumental analysis laboratory. In the experiment, students acquire fluorescence spectra of sensing molecules in the presence of mock sculpture samples and discuss the condition of the sculptures based on the levels of soluble iron detected. This real-world-based experiment allows students the chance to engage with ongoing research and further understand the challenges with early detection of corrosion. Most students successfully completed the experiment, wrote a …


Characterization Of Protease-Activated Receptor (Par) Ligands: Parmodulins Are Reversible Allosteric Inhibitors Of Par1-Driven Calcium Mobilization In Endothelial Cells, Disha M. Gandhi, Mark W. Majewski, Ricardo Rosas Jr., Kaitlin Kentala, Trevor J. Foster, Eric Greve, Chris Dockendorff May 2018

Characterization Of Protease-Activated Receptor (Par) Ligands: Parmodulins Are Reversible Allosteric Inhibitors Of Par1-Driven Calcium Mobilization In Endothelial Cells, Disha M. Gandhi, Mark W. Majewski, Ricardo Rosas Jr., Kaitlin Kentala, Trevor J. Foster, Eric Greve, Chris Dockendorff

Chemistry Faculty Research and Publications

Several classes of ligands for Protease-Activated Receptors (PARs) have shown impressive anti-inflammatory and cytoprotective activities, including PAR2 antagonists and the PAR1-targeting parmodulins. In order to support medicinal chemistry studies with hundreds of compounds and to perform detailed mode-of-action studies, it became important to develop a reliable PAR assay that is operational with endothelial cells, which mediate the cytoprotective effects of interest. We report a detailed protocol for an intracellular calcium mobilization assay with adherent endothelial cells in multiwell plates that was used to study a number of known and new PAR1 and PAR2 ligands, including an alkynylated version of the …


Chemical And Statistical Analysis Of Karst Groundwater Basin Signatures - Springfield, Mo, Benjamin E. Lockwood May 2018

Chemical And Statistical Analysis Of Karst Groundwater Basin Signatures - Springfield, Mo, Benjamin E. Lockwood

Graduate Theses/Dissertations

Springfield, MO is located on the Springfield Plateau physiographic province. The Springfield plateau contains a number of Mississippian aged units and is mainly capped by the Burlington-Keokuk Formation. The Burlington-Keokuk is a highly fossiliferous limestone with nodular and interbedded chert. Beneath the Burlington-Keokuk lies the Elsey, Reeds Spring, and Pierson Formations respectively which comprise the Springfield Plateau aquifer hydrostratigraphic unit. Within the Springfield Plateau aquifer, a well-developed karst system includes springs, sinkholes, and caves. The Springfield Plateau aquifer is the predominant source for springs and seeps in the Springfield area. The purpose of this study was to understand the differences …


Summary Of The Stock Structure Information Used For Determining Spatial Management Of The Index Species For The Scalefish Resources Of Northern Western Australia, Daniel J. Gaughan, Stephen J. Newman, Corey B. Wakefield Feb 2018

Summary Of The Stock Structure Information Used For Determining Spatial Management Of The Index Species For The Scalefish Resources Of Northern Western Australia, Daniel J. Gaughan, Stephen J. Newman, Corey B. Wakefield

WA Marine Stewardship Council report series

This paper was specifically developed in response to issues raised in an assessment of the Pilbara Trap Managed Fishery (PTMF) against the fishery sustainability standard of the Marine Stewardship Council (MSC).


Discovery And Development Of A Three-Component Oxidopyrylium Cycloaddition And Its Application Towards Alpha-Hydroxytropolone Synthesis, Michael P. D'Erasmo Feb 2018

Discovery And Development Of A Three-Component Oxidopyrylium Cycloaddition And Its Application Towards Alpha-Hydroxytropolone Synthesis, Michael P. D'Erasmo

Dissertations, Theses, and Capstone Projects

Historically, natural products have provided unique research opportunities and challenges for organic synthesis, chemical biology, and medicinal chemistry due to their molecular complexity and effects on physiological systems. The total synthesis of natural products has not only produced novel reaction methods and strategies capable of efficiently generating complex structural motifs but also granted access to sufficient quantities of otherwise scarce natural product material for clinical evaluation. These synthetic efforts have facilitated the formation of a transdisciplinary partnership between chemistry, biology, and medicine that has been paramount in elucidating the chemical and pharmaceutical utility of natural products. Chapter I of this …


Radical Chemistry In A Femtosecond Laser Plasma: Photochemical Reduction Of Ag+ In Liquid Ammonia Solution, Victoria K. Meader, Mallory G. John, Laysa M. Frias Batista, Syeda Ahsan, Katharine M. Tibbetts Jan 2018

Radical Chemistry In A Femtosecond Laser Plasma: Photochemical Reduction Of Ag+ In Liquid Ammonia Solution, Victoria K. Meader, Mallory G. John, Laysa M. Frias Batista, Syeda Ahsan, Katharine M. Tibbetts

Chemistry Publications

Plasmas with dense concentrations of reactive species such as hydrated electrons and hydroxyl radicals are generated from focusing intense femtosecond laser pulses into aqueous media. These radical species can reduce metal ions such as Au3+ to form metal nanoparticles (NPs). However, the formation of H2O2 by the recombination of hydroxyl radicals inhibits the reduction of Ag+ through back-oxidation. This work has explored the control of hydroxyl radical chemistry in a femtosecond laser-generated plasma through the addition of liquid ammonia. The irradiation of liquid ammonia solutions resulted in a reaction between NH3 and OH·, forming peroxynitrite and ONOO−, and significantly reducing …


Model Chemistry Study Of Choline And Urea Based Deep Eutectic Solvents, Libby Nicole Kellat Jan 2018

Model Chemistry Study Of Choline And Urea Based Deep Eutectic Solvents, Libby Nicole Kellat

ETD Archive

Gaussian and GaussView software were utilized to characterize interactions between choline salts and urea, which form a deep eutectic solvent (DES). The initial system studied was choline chloride and urea, at a 1:2 molar ratio, which is also known as reline. Subsequent systems, substituting the chloride anion with other anions (fluoride, bromide, and hydroxide), were studied to show that the system with greater calculated strength of interaction will have more non-ideal physical properties, such as melting point (found in literature). Observations regarding structure related to counterion electron density and hydrogen bonding were made throughout the studies.


Petrogenesis, Geochemistry, And Tectonic Setting Of A Basaltic Body Within Thegercus Formation Of Northern Iraq: First Record For Eocene Anorogenic Volcanicactivity In The Region, Yawooz A. Kettanah, Adnan H. Bamarni Jan 2018

Petrogenesis, Geochemistry, And Tectonic Setting Of A Basaltic Body Within Thegercus Formation Of Northern Iraq: First Record For Eocene Anorogenic Volcanicactivity In The Region, Yawooz A. Kettanah, Adnan H. Bamarni

Turkish Journal of Earth Sciences

An abnormally odd and rare occurrence of a basaltic body has been discovered in the middle of the Gercus Formation within the large, double-plunging NW-SE trending Bekhair Anticline to the north of Duhok city, northern Iraq. This is the first discovery of such a volcanic body within the widely exposed Gercus Formation in northern Iraq, southeastern Turkey, and western Iran. This volcanic body, named by the authors the Gercus Basalt, has a long tabular/lenticular shape with a total length of ~4.5 km and a thickness ranging between 1 to 16 m. It is exposed on both limbs of the anticline …


Direct Measurement Of Rupture Force Of Single Triazole Molecule By Atomic Force Microscope And Solid Phase Synthesis Of Monodisperse Polyethylene Glycols, Ashok Khanal Jan 2018

Direct Measurement Of Rupture Force Of Single Triazole Molecule By Atomic Force Microscope And Solid Phase Synthesis Of Monodisperse Polyethylene Glycols, Ashok Khanal

Dissertations, Master's Theses and Master's Reports

This dissertation includes two topics, which are related to each other: (1) Rupture force measurement of single triazole molecule by atomic force microscope (AFM) and (2) Solid phase stepwise synthesis of polyethylene glycols (PEGs).

The reaction of an alkyne and an azide to form a 1,2,3- triazole has found wide applications. However, the stability of triazole under mechanical stress is unclear. We investigated the cycloreversion at the single molecular level using atomic force microscopy. A mica surface functionalized with a molecule containing a 1,2,3-triazole moiety in the middle and an activated ester at the end was prepared. An AFM tip …