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Atmospheric Peroxyacetyl Nitrate (Pan): A Global Budget And Source Attribution, E. V. Fischer, D. J. Jacob, R. M. Yantosca, M. P. Sulprizio, D. B. Millet, J. Mao, F. Paulot, H. B. Singh, A. Roiger, L. Ries, R. W. Talbot, K. Dzepina, S. Pandey Deolal

Michigan Tech Publications

Peroxyacetyl nitrate (PAN) formed in the atmospheric oxidation of non-methane volatile organic compounds (NMVOCs) is the principal tropospheric reservoir for nitrogen oxide radicals (NOx =NO+NO2). PAN enables the transport and release of NOx to the remote troposphere with major implications for the global distributions of ozone and OH, the main tropospheric oxidants. Simulation of PAN is a challenge for global models because of the dependence of PAN on vertical transport as well as complex and uncertain NMVOC sources and chemistry. Here we use an improved representation of NMVOCs in a global 3-D chemical transport model (GEOS-Chem) and show that it …

A Semi-Lagrangian View Of Ozone Production Tendency In North American Outflow In The Summers Of 2009 And 2010, B. Zhang, R. C. Owen, J A Perlinger, A. Kumar, S. Wu, M. Val Martin, L. Kramer, D. Helmig, R. E. Honrath

Michigan Tech Publications

The Pico Mountain Observatory, located at 2225 m a.s.l. in the Azores Islands, was established in 2001 to observe long-range transport from North America to the central North Atlantic. In previous research conducted at the observatory, ozone enhancement (> 55 ppbv) in North American outflows was observed, and efficient ozone production in these outflows was postulated. This study is focused on determining the causes for high d[O3] / d[CO] values (~1 ppbv ppbv−1) observed in the summers of 2009 and 2010. The folded retroplume technique, developed by Owen and Honrath (2009), was applied to combine upwind FLEXPART transport …

Routes To N-Heterocycle Functionalized Poly(Arylene Ether Sulfone)S, Jesse L. Picker

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The synthesis of poly(arylene ether sulfone)s, with a pendant aryl iodide, was achieved via nucleophilic aromatic substitution (NAS) polycondensation of 3-iodo-3',5'-difluoro-diphenylsulfone. The polymer series was subjected to amino acid promoted, copper catalyzed coupling reactions with various N-heterocycles. The resulting polymers became crosslinked and insoluble in any organic solvents. The iodo monomer was then subjected to an amino acid promoted, copper catalyzed coupling reaction with carbazole. The successful synthesis of 3'-(9-carbazole) 3,5-difluorodiphenylsulfone is reported. A series of PAES containing a carbazole substituent were synthesized and characterized. The polymers were characterized by a combination of NMR spectroscopy, SEC, TGA, DSC, UV-Vis spectroscopy. …

Functionalized Sulfone And Sulfonamide Based Poly(Arylene Ether)S, Marina Andrejevic

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A series of fluorinated poly(arylene ether)s, PAE, bearing sulfonated pendent sulfonyl groups, was prepared. A range of Ion Exchange Capacity (IEC) values were achieved by varying the ratios of sulfonated and non sulfonated monomers. Incorporation of both of the monomers was confirmed by NMR spectroscopy and characterization of the thermal properties was done using thermogravimetric analysis (TGA) and differential scanning (DSC). Polymers with these IEC values were synthesized in order to explore their use as a potential alternatives to the widely studied proton exchange membrane, Nafion, with an IEC of 0.91 meq/g.

Using N-phenyl-3,5-difluorobenzene sulfonamide as the starting material a …

The Synthesis Of Polyimides Containing Oxyalkylene Units, Kristy Wickman

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A series of oxyalkylene containing diamines, 1,4-bis(2-(4-aminophenoxy)-ethoxy)benzene, 2,2-bis[4-(2-(4-nitrophenoxy)ethoxy)phenyl]hexafluoropropane, 9,9-bis(4-(2-(4-nitrophenoxy)ethoxy)phenyl)fluorene, and bis(4-(2-(4-nitrophenoxy)ethoxy)-phenyl)diphenylmethane, has been synthesized from the reduction of 1,4-bis(2-(4-nitrophenoxy)ethoxy)benzene, 2,2-bis[4-(2-(4-nitrophenoxy)ethoxy)phenyl]-hexafluoropropane, 9,9-bis(4-(2-(4-nitrophenoxy)ethoxy)phenyl)fluorene, bis(4-(2-(4-nitrophenoxy)ethoxy)phenyl)diphenylmethane, respectively. The diamine compounds were reacted reacted with 6FDA to obtain the corresponding polyimide. The polymerization was done in a one-pot reaction with m-cresol and isoquinoline. The polyimides displayed glass transition temperatures ranging from 186-231°C and thermal stability <400°C.

Reactivity Ratio Controlled Polycondensation As A Route To Synthesize Functional Poly(Arylene Ether)S, Godfred Boakye

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Two monomers, 4',3,5-trifluorodiphenylsulfone, 1, and 4',3,5-trifluorobenzophenone, 2, have been investigated for their potential use as special BB'B''type monomers to synthesize functionalized, linear PAEs via a process called reactivity ratio controlled polycondensation (RRCP). A model study with monomer 1 resulted in a mixture of unreacted starting material, two mono-substitution products (para-and meta-F substitution) and a significant amount of di-substitution products as evidenced by the GC/MS and 13C DEPT-90 NMR spectroscopy. Conversely, subjecting monomer 2 to similar conditions, using 3-aminophenol (3f) as the nucleophile, afforded mono-substitution exclusively. A series of functionalized, linear PAEs polymers were prepared by reaction of compound 2 with …

Synthesis And Biological Activity Of Indolinones, Kaleb Woodrow Cox

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Indolinones of the type known as Arylidene oxindoles have been demonstrated to possess a broad range of activity ranging from proten kinase inhibtors, cell-death inhibitors and tau protein binding agents. Small libraries of such molecules were designed and synthesized herein in modifications involving variously substituted halogen derivatives, N-alkylation of the indolinone nitrogen, and finally a new class of molecules, namely arylidene oxindoles possessing extended conjugation. The biological activities of such molecules were examined and the results disclosed herein.

Investigating Dna Barcoding Potentials And Genetic Structure In Ozobranchus Spp. From Atlantic And Pacific Ocean Sea Turtles, Triet Minh Truong

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The Ozobranchidae family is the smallest and least studied hirudinean taxon. Our research includes the largest molecular dataset yet reported for marine ozobranchids (Ozobranchus margoi and Ozobranchus branchiatus) with the most number of documented turtle hosts (57) from the Atlantic and Pacific Oceans to date of any marine turtle epibiont study. Turtle species sampled in this study include loggerheads (Caretta caretta), hawksbill (Eretmochelys imbricata), olive ridley (Lepidochelys olivacea), and green turtles (Chelonia mydas). Phylogenetic analyses of mitochondrial (COI) and nuclear ribosomal (18S and 28S) genes all support the monophyly of marine Ozobranchidae leeches with speciation occurring over an extensive period …

A Chemical Free Approach For Increasing The Biochemical Surface-Enhanced Raman Spectroscopy (Sers)-Based Sensing Capabilities Of Colloidal Silver Nanoparticles, Kevin Michael Dorney

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The unique optoelectronic properties of silver nanoparticles (AgNPs) have led to their explosive use in a multitude of both research and industrial settings in recent years. Localized surface plasmon resonance (LSPR) exhibited by AgNPs has been exploited extensively as a nano-scale probe in a variety of spectroscopic detection modalities, particularly in surface-enhanced Raman spectroscopy (SERS). The SERS effect is highly dependent upon the LSPR interaction with optical laser frequencies, thus optimization of LSPR via specific control of AgNP dimensionality and composition of the surrounding medium is vital for increasing the efficacy of SERS-based nano-sensing. This work aimed to augment LSPR …

The Synthesis Of Benzyloxy Substituted Dp-Ppv And Examination Of The Horner-Wadsworth-Emmons Reaction In The Synthesis Of Dp-Ppv, Jeremy M. Lear

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In the interest of the synthesis of polymers that have the potential to possess inherent light-emitting properties (LEDs) the synthesis of a novel 1,4-bis(chloromethyl)-benzene monomer, 5-benzyloxy-1,4-dichloromethyl-2,3-diphenyl benzene 78 was carried out. Monomer 78 was polymerized via the Gilch polymerization method to yield, poly(5-benzyloxy-2,3-diphenyl phenylene vinylene) 80. Polymer 80 was characterized by TGA (5% weight loss at 267°, GPC (weight average molecular weight of 7136 Da, number average molecular weight of 6603 Da) , UV-Vis and fluorescence studies (absorbance maximum at 406 nm, emission maximum at 510 nm).

The Horner-Wadsworth-Emmons variant of the Wittig was applied in the synthesis of poly(2,3-diphenyl-1,4-phenylenevinylene) …

The Synthesis Of 1,4-Bis(2-(4-(4-Fluorobenzoyl)Phenoxyethoxy)Benzene And Poly(Aralkyl Ether)S Derived From 1,4-Bis(2-Tosyloxyethoxy)Benzene, Juraj Drzic

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The reaction of 1,4-bis(2-tosyloxyethoxy)benzene or 1,4-bis(bromoethoxy)-benzene with 4-fluoro-4'-hydroxybenzophenone was carried out under a variety of conditions. Changes were made in solvent, reaction time, work-up and base. All attempts to generate a bis(fluorobenzophenone) monomer were unsuccessful. In some cases the presence of the half-product could be determined. In other cases, an elimination product was indicated. The ditosylate, 1,4-bis(2-tosyloxyethoxy)benzene was reacted with bisphenol-A, bisphenol-AF, bis(4-hydroxyphenyl)diphenylmethane and 9,9-bis(4-hydroxyphenyl)fluorene in a dioxane - water solution in the presence of sodium hydroxide to produce four polymers. The polymers were characterized by thermal analysis (TGA) to reveal 5% weight loss temperatures of 338°, 350°, 365° and …

Stop Cheating!: An Evaluation Of A Scientific Integrity Writing Strategy In General Chemistry I, Michelle L. Edwards

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Cheating in America has become an epidemic, which has unfortunately spread to academia. Researchers have long been interested in the trends in cheating behavior and the factors that influence these trends among undergraduate college students. Though cheating can take on many forms, in science, there is a deep concern about scientific misconduct related to research. Because training for future scientists begins in undergraduate courses, this study investigated the use of scientific integrity writing strategy in General Chemistry I at Wright State University. The goal of the study was to determine if providing scientific integrity and ethics training, while teaching students …