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Ryan Caylor, Ryan Caylor 2016 Concordia University - Portland

Ryan Caylor, Ryan Caylor

Matthew E. Wise

Ryan is a senior majoring in chemistry at Concordia University. He plans on graduating in the spring of 2017. After graduation Ryan plans on attending graduate school in the field of meteorology with an interest in becoming a weather man. Ryan is returning to the Pacific Northwest National Laboratory in the summer of 2015 to study the chemical composition of secondary organic aerosol particles. He is also a pitcher on the Concordia University baseball team.


Interaction Of Spliceosomal U2 Snrnp Protein P14 With Its Branch Site Rna Target, William Perea Vargas 2016 Graduate Center, City University of New York

Interaction Of Spliceosomal U2 Snrnp Protein P14 With Its Branch Site Rna Target, William Perea Vargas

All Dissertations, Theses, and Capstone Projects (2014-Present)

Newly transcribed precursor messenger RNA (pre-mRNA) molecules contain coding sequences (exons) interspersed with non-coding intervening sequences (introns). These introns must be removed in order to generate a continuous coding sequence prior to translation of the message into protein. The mechanism through which these introns are removed is known as pre-mRNA splicing, a two-step reaction catalyzed be a large macromolecular machine, the spliceosome, located in the nucleus of eukaryotic cells. The spliceosome is a protein-directed ribozyme composed of small nuclear RNAs (snRNA) and hundreds of proteins that assemble in a very dynamic process. One of these snRNAs, the U2 snRNA, is ...


Synthesis Of Two Monomers For Proton Exchange Membrane Fuel Cells (Pemfcs), Abdulmajeed A. Alayyaf 2016 East Tennessee State Universtiy

Synthesis Of Two Monomers For Proton Exchange Membrane Fuel Cells (Pemfcs), Abdulmajeed A. Alayyaf

Electronic Theses and Dissertations

The overall goal of this research is to synthesize two different monomers for proton exchange membrane (PEM) Fuel Cells. Such monomers are proposed to be polymerized to improve the efficiency and compatibility of electrodes and electrolytes in PEM fuel cells.

The first target is to synthesize 4-diazonium-3-fluoro PFSI zwitterionic monomer. Three steps were carried out in the lab. First one was the ammonolysis of 3-fluoro-4-nitrobenzenesulfonyl chloride. Second reaction was the bromination of Nafion monomer. The next coupling reaction, between brominated Nafion monomer and the 3-fluoro-4-nitrobenzenesulfonamide, was failed. The obstacles involve the harsh reaction condition and troublesome purification procedure.

The second ...


The Evaluation And Implementation Of Magnetic Fields For Large Strain Uniaxial And Biaxial Cyclic Testing Of Magnetorheological Elastomers., Dave Gorman, Niall Murphy, Ray Ekins, Steve Jerrams 2016 School of Manufacturing and Design Engineering, Dublin Institute of Technology

The Evaluation And Implementation Of Magnetic Fields For Large Strain Uniaxial And Biaxial Cyclic Testing Of Magnetorheological Elastomers., Dave Gorman, Niall Murphy, Ray Ekins, Steve Jerrams

Articles

Magnetorheological Elastomers (MREs) are “smart” materials whose physical properties are altered by the application of magnetic fields. In previous studies the properties of MREs have been evaluated under a variety of conditions, however little attention has been paid to the recording and reporting of the magnetic fields used in these tests [1]. Currently there is no standard accepted method for specifying the magnetic field applied during MRE testing. This study presents a detailed map of a magnetic field applied during MRE tests as well as providing the first comparative results for uniaxial and biaxial testing under high strain fatigue test ...


Computational Studies Of Spin Trapping Of Biologically Relevant Radicals By New Heteroaryl Nitrones, Eyram Asempa 2016 East Tennessee State Universtiy

Computational Studies Of Spin Trapping Of Biologically Relevant Radicals By New Heteroaryl Nitrones, Eyram Asempa

Electronic Theses and Dissertations

Heteroaryl nitrone spin traps have been suggested to act as free radical scavengers. The geometry optimizations and the single-point energies of the spin trapping reactions of the heteroaryl nitrones, 5,5-dimethylpyrroline-N-oxide (DMPO) and α-phenyl-N-t-butylnitrone (PBN) have been computationally studied using ab initio (Hartree-Fock (HF) and second-order Møller-Plesset (MP2)) methods and Density Functional Theory (DFT) methods. The effects of new heteroaryl substituents on a parent nitrone spin trap have been examined at the HF and MP2 levels with the 6-31G*, and cc-pVnZ (n=D, T, Q) basis sets. The thermodynamics of the spin trapping at the C-site and O-site ...


Synthesis Of Diazonium (Perfluoroalkyl) Arylsulfonimide Monomers From Perfluoro (3-Oxapent-4-Ene) Sulfonyl Fluoride For Proton Exchange Membrane Fuel Cell, Faisal Ibrahim 2016 East Tennessee State Universtiy

Synthesis Of Diazonium (Perfluoroalkyl) Arylsulfonimide Monomers From Perfluoro (3-Oxapent-4-Ene) Sulfonyl Fluoride For Proton Exchange Membrane Fuel Cell, Faisal Ibrahim

Electronic Theses and Dissertations

Two diazonium perfluoroalkyl arylsulfonimide (PFSI) zwitterionic monomers, 4-diazonium perfluoro(3-oxapent-4-ene)benzenesulfonimide (I) and 4-(trifluoromethyl)-2-diazonium perfluoro(3-oxapent-4-ene)benzenesulfonimide (II) have been synthesized from perfluoro(3-oxapent-4-ene) sulfonyl fluoride (POPF) for proton exchange membrane fuel cells. PFSI polymers are proposed as new electrolytes due to their better thermal stability, inertness to electrochemical conditions, and lower susceptibility to oxidative degradation and dehydration. For a better integration between the electrode and the electrolyte, the PFSI polymers are expected to be grafted onto the carbon electrode via the diazonium moiety.

All the reaction intermediates and the final product were characterized with 1H NMR, 19F ...


Energy Management Mechanisms Employed At The Human-Material Interface Of Traditional And Minimalist Shod Running, Nadine M. Lippa 2016 University of Southern Mississippi

Energy Management Mechanisms Employed At The Human-Material Interface Of Traditional And Minimalist Shod Running, Nadine M. Lippa

Dissertations

From recreational to elite athletes, greater than 50% of runners sustain overuse injuries each year, prompting substantial research efforts to identify causes of—and solutions to—the high injury rate. Different shoe types and material property degradation have been related to injury. Two popular footwear types are traditional shoes with thick graded soles and minimalist running footwear with thinner foam and/or non-graded soles. Notwithstanding 45 years of significant modifications to shoe design features, gained knowledge in kinesiology, and advanced technologies in polymer science, runner injury rates have not decreased and EVA foam has remained the primary running shoe midsole ...


Surface And Interfacial Design And Control Of High Performing Thermoplastics: Polysulfones And Beyond, Katrina Marie Knauer 2016 The University of Southern Mississippi

Surface And Interfacial Design And Control Of High Performing Thermoplastics: Polysulfones And Beyond, Katrina Marie Knauer

Dissertations

The study of a class of materials almost always begins with the development of an understanding of properties in the bulk state. However, it is the study of surface critical phenomena that has led to a number of new important insights into polymer behavior. A systematic understanding of physical properties in the immediate vicinity of surface and interfacial layers, which cannot be deduced by simple extrapolation of bulk properties, is of significant importance for advancements in polymer applications where the interface drives performance, such as in membranes, coatings, drug-delivery systems, medical devices, and composites.

First, the surface and interfacial modification ...


Curing Of Polymer Thermosets Via Click Reactions, Mark Richard Brei 2016 University of Southern Mississippi

Curing Of Polymer Thermosets Via Click Reactions, Mark Richard Brei

Dissertations

In the first project, an azide functional resin and tetra propargyl aromatic diamines were fabricated for use as a composite matrix. These systems take already established epoxy/amine matrices and functionalize them with click moieties. This allows lower temperatures to be used in the production of a thermoset part. These new systems yield many better mechanical properties than their epoxy/amine derivatives, but their Tgs are low in comparison.

The second project investigates the characterization of a linear system based off of the above azide functional resin and a difunctional alkyne. Through selectively choosing catalyst the linear system ...


Synthesis Of Microgel Polymers As Catalysts, Hannah N. Miller 2016 University of Arkansas, Fayetteville

Synthesis Of Microgel Polymers As Catalysts, Hannah N. Miller

Chemistry & Biochemistry Undergraduate Honors Theses

New developments in organic synthesis show promise in achieving the best catalytic properties for the hydrolysis of glycosidic bonds through microgel polymers and transition metal complexes. A monomer mix of ethylene glycol dimethacrylate, butyl acrylate, and styrene form miniemulsion polymers after sonication and exposure to UV light. Gravimetrical analysis is used to determine the most suitable polymerization conditions by performing experiments at varying pH values, temperatures, monomer amounts, initiator amounts, and lamp heights. The final data show that the best polymerization conditions are a pH of 10.50 at 0°C with a high monomer ratio, 20% initiator amount, and ...


Immobilization Of Heteropolyacids In Silica Gel, Opeyemi Adetola 2016 East Tennessee State University

Immobilization Of Heteropolyacids In Silica Gel, Opeyemi Adetola

Electronic Theses and Dissertations

Silica gels containing incorporated heteropolyacids (HPAs) were synthesized in acidic media by co-condensation of tetraethoxysilane (TEOS) with phosphotungstic or phosphomolybdic acids using sol-gel technique. Effect of the synthesis conditions on their structure and morphology was studied. Yields of modified materials were some lower as compared to non-modified silica gels. All materials were mesoporous but contained micropores in their structures. Presence of bands of Keggin’s structures in FT-IR spectra along with absence of XRD patterns of crystalline HPAs confirmed their fine incorporation into silica network. Particle sizes of modified materials were 800-1100 nm excepting for W-containing sample obtained with trimethylstearylammonium ...


Studies In Asymmetric Catalysis: Supramolecular Catalysis And Borane-Assisted Hydrogenation, Kazuya Toyama 2016 University of Nebraska-Lincoln

Studies In Asymmetric Catalysis: Supramolecular Catalysis And Borane-Assisted Hydrogenation, Kazuya Toyama

Student Research Projects, Dissertations, and Theses - Chemistry Department

Metal-catalyzed catalytic asymmetric reactions have gained enormous attentions and the utilities of such reactions have facilitated natural products syntheses to afford highly bioactive molecules. While these reactions have provided reliable methodologies to transform basic reactants into product(s) with highly enantio- and regioselective manners, the incompatibility with a many functional groups and the associated need to employ protecting groups increases the number of synthetic steps required. Herein, a solution to such an issue has been proposed in catalytic asymmetric hydroboration of styrene derivatives where supramolecular catalysts developed by Takacs et al. were used to achieve highly regio- and stereoselective reaction ...


Molecular Mechanism For The Biosynthesis And Regulation Of Secondary Metabolites In Lysobacter, Simon Tesfamichael Tombosa 2016 University of Nebraska-Lincoln

Molecular Mechanism For The Biosynthesis And Regulation Of Secondary Metabolites In Lysobacter, Simon Tesfamichael Tombosa

Student Research Projects, Dissertations, and Theses - Chemistry Department

This thesis presents regulatory and biosynthetic mechanisms by which microorganisms produce secondary metabolites that can potentially be developed into drugs beneficial to humans. The first section shows the role of small signaling molecules in regulating the production of one of the novel antifungal metabolites, heat stable antifungal factor (HSAF), from Lysobacter enzymogenes.

In the second part of the thesis I report our attempts to isolate and characterize the biosynthesis of WBP, a new secondary metabolite from Lysobacter antibioticus OH13. I have included the in-silico analysis of the gene cluster for WBP and the predicted biosynthetic pathway based on analysis of ...


Lipid Content And Biomass Analysis In Autotrophic And Heterotrophic Algal Species, Addie M. Lauder, Daniel P. Jones, Thomas E. Walker, Todd Allen 2016 Liberty University

Lipid Content And Biomass Analysis In Autotrophic And Heterotrophic Algal Species, Addie M. Lauder, Daniel P. Jones, Thomas E. Walker, Todd Allen

Montview Liberty University Journal of Undergraduate Research

Biofuels are a form of renewable energy derived from living matter, typically plants. The push for biofuels began in order to decrease the amount of carbon dioxide (CO2) released into the atmosphere, as biofuels are essentially carbon neutral. The idea is the same amount of CO2 the plants took in to perform photosynthesis will then be released in the burning of the biofuels. Algae is an excellent source of biofuels because it grows quickly and is versatile in terms of the type of fuel it can produce. The two most common mechanisms for algae growth are heterotrophic or photoautotrophic. Heterotrophically ...


Our Chemical Heritage: Its Impact On Our Daily Lives, Mary Virginia Orna 2016 The College of New Rochelle

Our Chemical Heritage: Its Impact On Our Daily Lives, Mary Virginia Orna

Sr. Mary Virgina Orna O.S.U.

No abstract provided.


Subcellular-Level Resolution Maldi-Ms Imaging Of Maize Leaf Metabolites By Maldi-Linear Ion Trap-Orbitrap Mass Spectrometer, Andrew R. Korte, Marna D. Yandeau-Nelson, Basil J. Nikolau, Young-Jin Lee 2016 Iowa State University

Subcellular-Level Resolution Maldi-Ms Imaging Of Maize Leaf Metabolites By Maldi-Linear Ion Trap-Orbitrap Mass Spectrometer, Andrew R. Korte, Marna D. Yandeau-Nelson, Basil J. Nikolau, Young-Jin Lee

Young Jin Lee

A significant limiting factor in achieving high spatial resolution for matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) imaging is the size of the laser spot at the sample surface. Here, we present modifications to the beam-delivery optics of a commercial MALDI-linear ion trap-Orbitrap instrument, incorporating an external Nd:YAG laser, beam-shaping optics, and an aspheric focusing lens, to reduce the minimum laser spot size from ~50 μm for the commercial configuration down to ~9 μm for the modified configuration. This improved system was applied for MALDI-MS imaging of cross sections of juvenile maize leaves at 5-μm spatial resolution using an oversampling ...


Multi-Matrix, Dual Polarity, Tandem Mass Spectrometry Imaging Strategy Applied To A Germinated Maize Seed: Toward Mass Spectrometry Imaging Of An Untargeted Metabolome, Adam Donald Feenstra, Rebecca L. Hansen, Young-Jin Lee 2016 Iowa State University

Multi-Matrix, Dual Polarity, Tandem Mass Spectrometry Imaging Strategy Applied To A Germinated Maize Seed: Toward Mass Spectrometry Imaging Of An Untargeted Metabolome, Adam Donald Feenstra, Rebecca L. Hansen, Young-Jin Lee

Young Jin Lee

Mass spectrometry imaging (MSI) provides high spatial resolution information that is unprecedented in traditional metabolomics analyses; however, the molecular coverage is often limited to a handful of compounds and is insufficient to understand overall metabolomic changes of a biological system. Here, we propose an MSI methodology to increase the diversity of chemical compounds that can be imaged and identified, in order to eventually perform untargeted metabolomic analysis using MSI. In this approach, we use the desorption/ionization bias of various matrixes for different metabolite classes along with dual polarities and a tandem MSI strategy. The use of multiple matrixes and ...


Matrix Assisted Laser Desorption/Ionization-Mass Spectrometry Imaging (Maldi-Msi) For Direct Visualization Of Plant Metabolites In Situ, Drew Sturtevant, Young-Jin Lee, Kent D. Chapman 2016 University of North Texas

Matrix Assisted Laser Desorption/Ionization-Mass Spectrometry Imaging (Maldi-Msi) For Direct Visualization Of Plant Metabolites In Situ, Drew Sturtevant, Young-Jin Lee, Kent D. Chapman

Young Jin Lee

Direct visualization of plant tissues by matrix assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI) has revealed key insights into the localization of metabolites in situ. Recent efforts have determined the spatial distribution of primary and secondary metabolites in plant tissues and cells. Strategies have been applied in many areas of metabolism including isotope flux analyses, plant interactions, and transcriptional regulation of metabolite accumulation. Technological advances have pushed achievable spatial resolution to subcellular levels and increased instrument sensitivity by several orders of magnitude. It is anticipated that MALDI-MSI and other MSI approaches will bring a new level of understanding to metabolomics ...


Effective Evaluation Of Catalytic Deoxygenation For In Situ Catalytic Fast Pyrolysis Using Gas Chromatography–High Resolution Mass Spectrometry, D. Paul Cole, Young-Jin Lee 2016 Iowa State University

Effective Evaluation Of Catalytic Deoxygenation For In Situ Catalytic Fast Pyrolysis Using Gas Chromatography–High Resolution Mass Spectrometry, D. Paul Cole, Young-Jin Lee

Young Jin Lee

Effective deoxygenation in catalytic fast pyrolysis (CFP) is crucial for bio-oil stabilization and its successful commercialization. Herein, we utilize a new analytical platform that couples gas chromatography (GC) to dopant-assisted atmospheric pressure chemical ionization (dAPCI) time-of-flight mass spectrometry (TOF MS) to evaluate catalytic deoxygenation of cellulose pyrolysis. Soft ionization and accurate mass measurement through dAPCI-TOF MS allows direct chemical composition analysis of GC-separated molecules, regardless of their presence in the database. The analytical approach was successfully demonstrated for its ability to evaluate catalytic efficiency of different catalysts and to monitor the change in CFP reaction products with catalyst-to-biomass load ratio ...


Maldi-Ms Analysis And Imaging Of Smallmolecule Metabolites With 1,5-Diaminonaphthalene (Dan), Andrew R. Korte, Young-Jin Lee 2016 Iowa State University

Maldi-Ms Analysis And Imaging Of Smallmolecule Metabolites With 1,5-Diaminonaphthalene (Dan), Andrew R. Korte, Young-Jin Lee

Young Jin Lee

1,5-diaminonaphthalene (DAN) has previously been reported as an effective matrix for matrix-assisted laser desorption ioni- zation-mass spectrometry of phospholipids. In the current work, we investigate the use of DAN as a matrix for small metab- olite analysis in negative ion mode. DAN was found to provide superior ionization to the compared matrices for MW < ~400 Da; however, 9-aminoacridine (9-AA) was found to be superior for a uridine diphosphate standard (MW 566 Da). DAN was also found to provide a more representative profile of a natural phospholipid mixture than 9-AA. Finally, DAN and 9-AA were applied for imaging of metabolites directly from corn leaf sections. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.


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