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Novel Relative Spontaneous Ignition Temperature Determination Using Carbon Dioxide Onset With Sta/Ir, Antonio David Trevino 2018 Stephen F. Austin State University

Novel Relative Spontaneous Ignition Temperature Determination Using Carbon Dioxide Onset With Sta/Ir, Antonio David Trevino

Electronic Theses and Dissertations

Simultaneous thermal analysis, coupled with infrared spectroscopy (STA/IR), was utilized to monitor the evolution of gaseous products during the thermal degradation of samples from Triadica sebifera (Chinese tallow), Ligustrum sinense (Chinese privet), and Ilex vomitoria (yaupon) plants. Identification of carbon dioxide was successful with a spectral match of 90.2 percent and further used in the determination of relative spontaneous ignition temperature, or RSIT. The RSIT value during the growing season for Chinese tallow, Chinese tallow stem, Chinese privet, and Yaupon were 208.4°C, 250.3°C, 210.1°C, and 232.3°C respectively. During the dormant ...


Learning Chemistry In English: Challenges Faced By Non-Native English Speakers, Arwa A. Alshehri 2018 Missouri State University

Learning Chemistry In English: Challenges Faced By Non-Native English Speakers, Arwa A. Alshehri

MSU Graduate Theses

Every year many international students come to study in the United States. In addition to all the challenges associated with coming to a new country, non-native English speakers (NNES) face the additional challenge of having to learn their content in English. Therefore, in this project, I recruited NNES participants from general chemistry courses since preliminary inquiries indicated that they have the largest enrollments. Because there were relatively few students at MSU who are non-native English speakers studying chemistry, I used a case study design to be able to extract generalizations from an in-depth study of a few individuals. The aim ...


Electrogenerated Chemiluminescence Of Transition Metal Octaethylporphyrin And Tetraphenylporphyrin/Tri-N-Propylamine System, Jamie Lee Gray 2018 Missouri State University

Electrogenerated Chemiluminescence Of Transition Metal Octaethylporphyrin And Tetraphenylporphyrin/Tri-N-Propylamine System, Jamie Lee Gray

MSU Graduate Theses

The electrogenerated chemiluminescence (ECL) of octaethylporphyrin (OEP), tetraphenylporphyrin (TPP) and a series of metal-ligand porphyrin complexes (Zinc, Copper, Palladium, Platinum, Ruthenium, Vanadium, Cobalt and Nickel) in CH2Cl2 is reported. ECL was generated upon sweep to positive potentials using tri-n-propylamine (TPrA) as an oxidative-reductive coreactant. ECL efficiencies were between 0.010 and 0.770 using Ru(bpy)3(PF6)2 (bpy = 2,2’-bpyridine) as a relative standard (ecl = 1). The ECL intensity peaks at a potential corresponding to oxidation of the complexes and TPrA, suggesting that the same excited states are formed in both photoluminescence and ECL. Although the ECL ...


Modern Electronic Structure Theory: The Search For Chemical Accuracy, Jonathan Prince 2018 Boise State University

Modern Electronic Structure Theory: The Search For Chemical Accuracy, Jonathan Prince

Boise State University Theses and Dissertations

Electronic structure theory has progressed significantly within the last few decades, venturing far from the early days of the Hartree-Fock self-consistent field method. Modern electronic structure theory focuses on compound methods, which operate under the idea that we can take a lower level of theory computation (typically, a result from Hartree-Fock, Configuration Interaction, Coupled Cluster or Moller-Plesset perturbation theory) and add in higher level of the theory corrections such as extrapolations to the infinite basis set limit, as well as, relativistic effects.

Using the Gaussian-n, Complete Basis Set and Weizmann compound methods, we were able to provide theoretical evidence to ...


Nmr Spectroscopic Properties Of Nucleotides, And A New Method Of Numeric Calculation Of Raman Intensities For Organic Molecules, William R. Ehrhardt 2018 Missouri State University

Nmr Spectroscopic Properties Of Nucleotides, And A New Method Of Numeric Calculation Of Raman Intensities For Organic Molecules, William R. Ehrhardt

MSU Graduate Theses

General and accurate computational methodologies are currently lacking for large chemical systems. This is primarily due to the computational expense required to perform calculations on systems with one hundred or more atoms. Calculated spectroscopic properties could aid in the process of elucidating structural features of large biologically relevant molecules if accurate and inexpensive methods are developed. Towards this end the first steps were taken to design a general methodology for predicting NMR chemical shifts of large nucleic acid systems. It was found that HF and semi-empirical methods were not sufficient for optimization of nucleobases, and therefore larger nucleotide or nucleic ...


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

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

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 ...


Chemical Strategies For Drug Development Of Fucose-Truncated Ipomoeassin F Analogues, Melissa Hirsch 2018 University of Arkansas, Fayetteville

Chemical Strategies For Drug Development Of Fucose-Truncated Ipomoeassin F Analogues, Melissa Hirsch

Theses and Dissertations

Natural product synthesis has many applications in the field of chemical biology, due to the protein binding affinity to the complex three-dimensional structure. However, synthetic and structure-activity relationship studies concerning certain drug targets are scarce. For example, members of the ipomoeassin family have exhibited anti-cancer properties, but cost-effective optimization of these compounds has not yet been extensively studied. Ipomoeassin F, a natural glycoresin isolated from the leaves of the Ipomoea squamosa plant in the Suriname rainforest, has shown high cytotoxicity, with IC50 values measured at the low nanomolar range. Two studies by Postema and Fuerstner have outlined synthesis pathways for ...


Bayesian Analytical Approaches For Metabolomics : A Novel Method For Molecular Structure-Informed Metabolite Interaction Modeling, A Novel Diagnostic Model For Differentiating Myocardial Infarction Type, And Approaches For Compound Identification Given Mass Spectrometry Data., Patrick J. Trainor 2018 University of Louisville

Bayesian Analytical Approaches For Metabolomics : A Novel Method For Molecular Structure-Informed Metabolite Interaction Modeling, A Novel Diagnostic Model For Differentiating Myocardial Infarction Type, And Approaches For Compound Identification Given Mass Spectrometry Data., Patrick J. Trainor

Electronic Theses and Dissertations

Metabolomics, the study of small molecules in biological systems, has enjoyed great success in enabling researchers to examine disease-associated metabolic dysregulation and has been utilized for the discovery biomarkers of disease and phenotypic states. In spite of recent technological advances in the analytical platforms utilized in metabolomics and the proliferation of tools for the analysis of metabolomics data, significant challenges in metabolomics data analyses remain. In this dissertation, we present three of these challenges and Bayesian methodological solutions for each. In the first part we develop a new methodology to serve a basis for making higher order inferences in metabolomics ...


Synthesis, Characterization, And Applications Of Ammonium/Phosphonium Chitosan Derivatives For Investigative Dna Interactions, Quinton Kirk Wyatt 2018 Missouri State University

Synthesis, Characterization, And Applications Of Ammonium/Phosphonium Chitosan Derivatives For Investigative Dna Interactions, Quinton Kirk Wyatt

MSU Graduate Theses

Chitosan is examined as a non-viral vector capable of efficient gene delivery due to its favorable properties such as biodegradability, biocompatibility, and is non-toxic to mammalian cells. Cell modifications and vector permeability are enhanced in non-viral vectors that incorporate electrostatic interactions. This work synthesizes cationic (N+, P+) chitosan derivatives, to enhance electrostatic interactions towards nucleotides, using amide coupling agents EDC and HOBt. The final chitosan derivatives will bear cationic functional groups (N+, P+) with various alkyl groups (Me, Et, Pr, Ph) to examine their affinities to nucleotides and antifungal properties. mPEG grafted cationic chitosan derivatives were also synthesized to examine ...


Piezoresponse, Mechanical, And Electrical Characteristics Of Synthetic Spider Silk Nanofibers, Nader Shehata, Ishac Kandas, Ibrahim Hassounah, Patrik Sobolčiak, Igor Krupa, Miroslav Mrlik, Anton Popelka, Jesse Steadman, Randolph Lewis 2018 Utah State University

Piezoresponse, Mechanical, And Electrical Characteristics Of Synthetic Spider Silk Nanofibers, Nader Shehata, Ishac Kandas, Ibrahim Hassounah, Patrik Sobolčiak, Igor Krupa, Miroslav Mrlik, Anton Popelka, Jesse Steadman, Randolph Lewis

Biology Faculty Publications

This work presents electrospun nanofibers from synthetic spider silk protein, and their application as both a mechanical vibration and humidity sensor. Spider silk solution was synthesized from minor ampullate silk protein (MaSp) and then electrospun into nanofibers with a mean diameter of less than 100 nm. Then, mechanical vibrations were detected through piezoelectric characteristics analysis using a piezo force microscope and a dynamic mechanical analyzer with a voltage probe. The piezoelectric coefficient (d33) was determined to be 3.62 pC/N. During humidity sensing, both mechanical and electric resistance properties of spider silk nanofibers were evaluated at varying high-level ...


Fuel Specific Emissions Trends For In-Use Medium And Heavy-Duty Vehicle Fleets In California, Molly J. Haugen 2018 University of Denver

Fuel Specific Emissions Trends For In-Use Medium And Heavy-Duty Vehicle Fleets In California, Molly J. Haugen

Electronic Theses and Dissertations

New heavy-duty vehicle regulations have caused significant reductions in hazardous air pollutants, such as particulate matter (PM) and nitrogen oxides (NOx), due to better engine management and utilization of advanced after-treatment systems. The University of Denver has collected data for gaseous and PM emission measurements from on-road heavy-duty vehicles (HDVs). The On-Road Heavy-Duty Vehicle Emissions Measurement System (OHMS) collected fuel specific emission information on individual HDVs of in-use fleets at two California locations in the spring of 2013, 2015 and 2017. These complimentary fleets, studied over multiple years, produced 7,075 measurements of gaseous and particle emission data providing ...


Investigations Into Factors Affecting The Wpd-Loop In The Protein Tyrosine Phosphatases Yoph And Ptp1b, Gwendolyn Moise 2018 Utah State University

Investigations Into Factors Affecting The Wpd-Loop In The Protein Tyrosine Phosphatases Yoph And Ptp1b, Gwendolyn Moise

All Graduate Theses and Dissertations

The research in this dissertation documents connections between the primary amino acid sequence of proteins, the dynamics of proteins, and their catalytic function. This research project studied two proteins called protein-tyrosine phosphatases (PTPs): the human enzyme PTP1B, and the bacterial enzyme YopH. PTP1B is a human enzyme that down regulates the insulin receptor on the outer cellular membrane, and causes the insulin receptor to be less responsive to insulin. A deeper knowledge of how PTP1B is different from other human PTPs might be useful in designing drugs to increase insulin sensitivity in diabetics. Yersinia Pestis is the bacteria that caused ...


1,1´-Diethyl-2,2´,3,3´,4,4´,5,5´-Octamethylferrocenium Tetracyanoethylenide, [Fe(C5etme4)2]+[Tcne]–, A Charge-Transfer Salt Magnetic Solid With A Novel Structural Motif, T. David Harris, Michael Castellani, Arnold L. Rheingold, William M. Reiff, Gordon T. Yee 2018 Marshall University

1,1´-Diethyl-2,2´,3,3´,4,4´,5,5´-Octamethylferrocenium Tetracyanoethylenide, [Fe(C5etme4)2]+[Tcne]–, A Charge-Transfer Salt Magnetic Solid With A Novel Structural Motif, T. David Harris, Michael Castellani, Arnold L. Rheingold, William M. Reiff, Gordon T. Yee

Michael P. Castellani

1,1′-Diethyl-2,2′,3,3′,4,4′,5,5′-octamethylferrocene has been utilized as a one-electron donor in the synthesis of a tetracyanoethylene charge-transfer salt, [Fe(C5EtMe4)2]+[TCNE]. Structural characterization shows that it adopts an arrangement of anions and cations completely different from the usual π stacking seen in analogous decamethylferrocenium compounds. The TCNE radical sits along side of the ferrocene, nearly perpendicular to the planes of the C5 rings. The nearly square geometry of the TCNE anion creates disorder over two orientations. [Fe(C5EtMe4)2]+[TCNE] is a simple paramagnet ...


1 Halogen Oxidation Reactions Of (C5ph5)Cr(Co)3 And Lewis Base Addition To [(C5ph5)Cr(Μ-X)X]2: Electrochemical, Magnetic, And Raman Spectroscopic Characterization Of [(C5ph5)Crx2]2 And (C5ph5)Crx2(Thf) (X = Cl, Br, I). X-Ray Crystal Structure Of [(C5ph5)Cr(Μ-Cl)Cl]2, Marc A. Hutton, James C. Durham, Robert W. Grady, Brett E. Harris, Carter S. Jarrell, J. Matthew Mooney, Michael Castellani, Arnold L. Rheingold, Ulrich Kölle, Brenda J. Korte, Roger D. Sommer, Gordon T. Yee, J. Matthew Boggess, Roman S. Czernuszewicz 2018 Marshall University

1 Halogen Oxidation Reactions Of (C5ph5)Cr(Co)3 And Lewis Base Addition To [(C5ph5)Cr(Μ-X)X]2: Electrochemical, Magnetic, And Raman Spectroscopic Characterization Of [(C5ph5)Crx2]2 And (C5ph5)Crx2(Thf) (X = Cl, Br, I). X-Ray Crystal Structure Of [(C5ph5)Cr(Μ-Cl)Cl]2, Marc A. Hutton, James C. Durham, Robert W. Grady, Brett E. Harris, Carter S. Jarrell, J. Matthew Mooney, Michael Castellani, Arnold L. Rheingold, Ulrich Kölle, Brenda J. Korte, Roger D. Sommer, Gordon T. Yee, J. Matthew Boggess, Roman S. Czernuszewicz

Michael P. Castellani

The 17-electron complex (C5Ph5)Cr(CO)3 reacts with halogens (C6H5I•Cl2, Br2, and I2) in C6H6 to yield the dimeric oxidation products [(C5Ph5)Cr(m-X)X]2 as thermally stable solids. Reactions with other chlorinating agents similarly yield [(C5Ph5)CrCl2]2. An X-ray crystal structure of [(C5Ph5)Cr(m-Cl)Cl]2 was obtained. The magnetic properties of the Cl2 bridged dimer have been determined and modeled using the usual isotropic hamiltonian which yields J/k = –30 K. Low-temperature (77 K) Raman spectra of solid [(C5Ph5)CrX2]2 (X = Cl, I) allow assignments to be made for the metal-ring ...


Working With Organic Peroxides In The Academic Lab, Patrick Dussault 2018 University of Nebraska-Lincoln

Working With Organic Peroxides In The Academic Lab, Patrick Dussault

Organic Peroxides: Safety Issues

ABSTRACT: The following is a brief introduction to peroxide safety from the viewpoint of a synthetic chemist. Major topics include: classes of organic peroxides; peroxide reactivity; hazard identification and minimization; reaction monitoring; and, hazards associated with auto-oxidation of peroxidizable solvents.

KEYWORDS: peroxide, hydroperoxide, hydroperoxyacetal, ozonide, perester, dihydroperoxide, monoperoxyacetal, active oxygen, peroxide strips, TLC indicator, self-accelerating decomposition, radical, exothermicity, transition metals.

CONTENTS: 1. Literature resources 2. Major classes of peroxides 3. Basis for peroxide reactivity 4. Determining reactivity and minimizing hazards a. Steps to take before an experiment b. Minimizing hazard during reactions c. Monitoring reactions d. Working with isolated peroxides ...


Ultrafast And Nonlinear Spectroscopy Of Nanomaterials, Rami Anthony Khoury 2018 Louisiana State University and Agricultural and Mechanical College

Ultrafast And Nonlinear Spectroscopy Of Nanomaterials, Rami Anthony Khoury

LSU Doctoral Dissertations

Ultrafast and nonlinear spectroscopies are implemented in the investigation of excited-state dynamics and structural properties of materials and nanomaterials. In the first study, the excited-state dynamics of size-dependent colloidal TiO2-Au nanocomposites are investigated using ultrafast transient absorption spectroscopy. The dynamics corresponding to the plasmon depletion band are characterized by electron-phonon and phonon-phonon coupling lifetimes that are observed to be independent of the gold nanocluster shell thickness. The excited-state dynamics corresponding to the interband transition of gold is also spectrally overlapped with the interfacial electron transfer lifetime, which is shown to decrease as the nanocluster shell thickness increases. In ...


Collisional Quenching Of Highly Excited H2 Due To H2 Collisions, Yier Wan, B. H. Yang, P. C. Stancil, Balakrishnan Naduvalath, Nikhil J. Parekh, R. C. Forrey 2018 The University of Georgia

Collisional Quenching Of Highly Excited H2 Due To H2 Collisions, Yier Wan, B. H. Yang, P. C. Stancil, Balakrishnan Naduvalath, Nikhil J. Parekh, R. C. Forrey

Chemistry and Biochemistry Faculty Publications

Rate coefficients for pure rotational quenching in H2(ν 1 = 0, j 1) + H2(ν 2 = 0, j 2) collisions from initial levels of j 1 = 2–31 (j 2 = 0 or 1) to all lower rotational levels are presented. We carried out extensive quantum mechanical close-coupling calculations based on a recently published H2–H2 potential energy surface (PES) developed by Patkowski et al. that has been demonstrated to be more reliable than previous work. Rotational transition cross sections with initial levels of j 1 = 2–14, 18, 19, 24, and 25 were computed for energies ranging from 10−6 ...


The Fate Of Arsenic In Noah’S Flood, Aaron R. Hutchison, Campbell F. Bortel 2018 Cedarville University

The Fate Of Arsenic In Noah’S Flood, Aaron R. Hutchison, Campbell F. Bortel

The Proceedings of the International Conference on Creationism

One potential consequence of Noah’s Flood would be the mobilization of toxic elements such as arsenic (As), a group 15 metalloid with a significant solubility and redox chemistry in water and a high toxicity to human beings. This paper discusses the likely chemistry of arsenic during the Flood. The Flood would have released arsenic through hydrothermal activity, volcanic eruptions, and weathering of crustal rock. Arsenic in hydrothermal fluid would likely be rapidly precipitated by sulfides. Likewise, much of the arsenic in volcanoes would actually be deposited sub-surface as sulfides. In the presence of oxygen-rich waters, these sulfide minerals can ...


Hiv-1 Integrase-Targeted Short Peptides Derived From A Viral Protein R Sequence, Xue Zhi Zhao, Mathieu Métifiot, Evgeny Kiselev, Jacques Kessl, Kasthuraiah Maddali, Christophe Marchand, Mamuka Kvaratskhelia, Yves Pommier, Terrence R. Burke Jr. 2018 Center of Cancer Research

Hiv-1 Integrase-Targeted Short Peptides Derived From A Viral Protein R Sequence, Xue Zhi Zhao, Mathieu Métifiot, Evgeny Kiselev, Jacques Kessl, Kasthuraiah Maddali, Christophe Marchand, Mamuka Kvaratskhelia, Yves Pommier, Terrence R. Burke Jr.

Faculty Publications

HIV-1 integrase (IN) inhibitors represent a new class of highly effective anti-AIDS therapeutics. Current FDA-approved IN strand transfer inhibitors (INSTIs) share a common mechanism of action that involves chelation of catalytic divalent metal ions. However, the emergence of IN mutants having reduced sensitivity to these inhibitors underlies efforts to derive agents that antagonize IN function by alternate mechanisms. Integrase along with the 96-residue multifunctional accessory protein, viral protein R (Vpr), are both components of the HIV-1 pre-integration complex (PIC). Coordinated interactions within the PIC are important for viral replication. Herein, we report a 7-mer peptide based on the shortened Vpr ...


Removal Of Acid Yellow 25 From Aqueous Solution By Chitin Prepared From Waste Snow Crab Legs, Chin-Chuan Wei, Inoka K. Pathiraja, Emily Fabry, Kyle Schafer, Nick Schimp, Tuo-Ping Hu, Lawrence P. Norcio 2018 Southern Illinois University Edwardsville

Removal Of Acid Yellow 25 From Aqueous Solution By Chitin Prepared From Waste Snow Crab Legs, Chin-Chuan Wei, Inoka K. Pathiraja, Emily Fabry, Kyle Schafer, Nick Schimp, Tuo-Ping Hu, Lawrence P. Norcio

SIUE Faculty Research, Scholarship, and Creative Activity

Acid Yellow 25 (AY25) is used in the textile industry for dyeing of natural and synthetic fibers, and is also used as a coloring agent in paints, inks, plastics, and leathers. Effluents from such industries are major sources of water pollution. Hence, it is important to find simple, efficient, and inexpensive ways to remove these dyes from wastewater. Here, we determined the suitability of chitin extracted from waste crab legs as an adsorbent for removing AY25 dye. The adsorption kinetics was modeled using pseudo-first order, pseudo-second order, and intraparticle diffusion equations to determine the rate controlling step. Results showed that ...


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