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Full-Text Articles in Chemistry
Green Chemistry: Progress And Barriers, Sarah A. Green
Green Chemistry: Progress And Barriers, Sarah A. Green
Michigan Tech Publications
Green chemistry can advance both the health of the environment and the primary objectives of the chemical enterprise: to understand the behavior of chemical substances and to use that knowledge to make useful substances. We expect chemical research and manufacturing to be done in a manner that preserves the health and safety of workers; green chemistry extends that expectation to encompass the health and safety of the planet. While green chemistry may currently be treated as an independent branch of research, it should, like safety, eventually become integral to all chemistry activities. While enormous progress has been made in shifting …
Poly(Arylene Ether Sulfone)S With Ammonium Groups Located On Pendent Phenyl Sulfonyl Moieties For Anionic Exchange Membranes, Trevor I. Schumacher
Poly(Arylene Ether Sulfone)S With Ammonium Groups Located On Pendent Phenyl Sulfonyl Moieties For Anionic Exchange Membranes, Trevor I. Schumacher
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A series of poly(aryl ether sulfone)s with varying percentages of ammonium groups, located on truly pendent positions, was prepared and characterized. The initial polymers were prepared by nucleophilic aromatic substitution (NAS) polycondensation reactions of varying ratios of 3,5-difluoro-4'-methyldiphenylsulfone and 4,4'-difluorodiphenylsulfone, with bisphenol-A as the nucleophilic reaction partner. The tolyl groups in the resulting polymers were subjected to radical bromination with N-bromosuccinimide, followed by amination with three different amines: trimethylamine, dimethylhexadecylamine, and N-methylimidazole. The polymers were characterized by 1H and 13C NMR spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. With the exception of the 100% functionalized polymers, tough films were observed …
Vespucci: A Free, Cross-Platform Software Tool For Spectroscopic Data Analysis And Imaging, Daniel Patrick Foose
Vespucci: A Free, Cross-Platform Software Tool For Spectroscopic Data Analysis And Imaging, Daniel Patrick Foose
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Vespucci is a software application developed for imaging and analysis of hyperspectral datasets. Vespucci offers several advantages over other software packages, including a simple user interface, no cost, and less restrictive licensing. Vespucci incorporates several analysis techniques including univariate imaging, principal components analysis, partial-least-squares regression, vertex components analysis and k- means clustering. Additionally, Vespucci can perform a number of useful data-processing operations, including filtering, normalization, baseline correction, and background subtraction. Datasets that consist of spatial or temporal data with a corresponding digital signal, including spectroscopic images, mass spectrometric images, and X-ray diffraction data can be processed in this software. The …
Routes To 1,3,4 - Oxadiazol-2(3h)-Ones, Karunakar Reddy Madaram
Routes To 1,3,4 - Oxadiazol-2(3h)-Ones, Karunakar Reddy Madaram
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Various 1,3,4-oxadiazol-2(3H)-ones were synthesized by reaction of the bromocarbonylhydrazine salt(35) obtained from treatment of 4-bromo-3-phenylsydnone(34) with HCl with the corresponding acid chlorides in DME. The structures were confirmed by their physical, analytical and spectral data (IR, GC/MS, 1H and 13C NMR and CHN analysis). In general these compounds were synthesized in good to excellent yields and it is planned to continue exploration of their chemical behavior as a guide to their potential antimicrobial activity. As an initial approach to the synthesis of the desired 1,3,4-oxadiazol-2(3H)-ones, the starting material, 3-phenylsydnone, was prepared in 2 steps from commercially available N-phenylglycine in good …
Synthesis, Characterization, And Polymerization Of Sulfonamide Based Bifunctional Monomers, Brady Hall
Synthesis, Characterization, And Polymerization Of Sulfonamide Based Bifunctional Monomers, Brady Hall
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A series of bifunctional monomers based on N,N-diallylbenzenesulfonamides with varying groups on the benzene moiety were investigated. The main goal of this project was to polymerize these monomers using radical and acyclic diene metathesis (ADMET) polymerization methods to polymerize through the allyl groups, and nucleophilic aromatic substitution (SNAr) to polymerize through the fluorine groups on the phenyl ring. Using phenyl substituted benzenesulfonyl chloride derivatives as a starting material, a series of N,N-diallylbenzenesulfonamide derivatives were prepared. The ADMET and radical cyclopolymerizations were monitored by 1H NMR spectroscopy, observing the disappearance of signals for the allyl groups in both, and the appearance …
Synthesis And Characterization Of Functionalized Poly(Arylene Ether Sulfone)S Using Click Chemistry, Kavitha Neithikunta
Synthesis And Characterization Of Functionalized Poly(Arylene Ether Sulfone)S Using Click Chemistry, Kavitha Neithikunta
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Poly(arylene ether sulfone)s with pendent aryl iodide group was successfully synthesized via Nucleophilic aromatic polycondensation of 1-(3,5-difluorophenyl sulfonyl)-4-iodobenzene using 4,4’-difluorodiphenylsulfone (DFDPS) and Bisphenol A in the ratio 25:75:100. Iodo monomer was prepared by reacting 3,5-difluorodiphenyl sulfone with N-iodo succinimide (NIS). Using GC/MS and NMR spectroscopy, the quantitative analysis was done to this monomer. Modification was done to iodo copolymer using sodium azide and copper sulfate as catalyst to form azide copolymer. Further modification of the azide copolymer to triazole copolymers via Click Chemistry using different alkynes such as 1-octyne, phenyl acetylene, propargyl alcohol and acetylenedicarboxylic acid. Polymers characterization was done …
Theoretical Estimation Of PkA'S Of Pyrimidines And Related Heterocycles, Rachael Ann Wessner
Theoretical Estimation Of PkA'S Of Pyrimidines And Related Heterocycles, Rachael Ann Wessner
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Pyrimidines and related heterocycles are an important class of compounds with a wide variety of applications. As a result, there is great interest in the chemical properties of these compounds, specifically their pKa's. Despite the importance of these compounds their reported pKa's are often only approximations or are completely absent from literature. Experimentally measuring pKa's can be challenging, especially if the pKa is below zero. Alternatively, pKa's can be estimated computationally using a Quantitative Structure-Activity Relationship (QSAR). However, most of the compounds included in this study exist as two or more forms that arise from tautomerism. Tautomerism complicates the estimation …
An Investigation Of The Adsorption Behavior Between Silver Nanoparticles (Agnps) And Corundum (Α-Al2O3) At Environmental Ph Values Using Inductively-Coupled Plasma Optical Emission Spectroscopy (Icp-Oes) And Raman Spectroscopy, Kevin Andrew O'Neil
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With the increased use of silver nanoparticles (AgNPs) in consumer products, the need to monitor their release into environmental soils has become critical. Although minerals make up a large component of soils, research on their interactions with AgNPs is still limited. Furthermore, the majority of the existing research focused on silica-based minerals rather than metal oxides, which is the second most abundant mineral type in the earth's crust. This study examined for the first time the aqueous interaction between the widely used, spherical Creighton AgNPs and a-corundum (a-Al2O3), a representative non-silica-based mineral, at environmentally relevant pH values (6-11). Samples were …
Synthesis And Characterization Of Peek Analogues Utilizing 3,5- And 2,4-Difluorobenzophenone., Zachary Ewing
Synthesis And Characterization Of Peek Analogues Utilizing 3,5- And 2,4-Difluorobenzophenone., Zachary Ewing
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Two routes to semi-crystalline, potentially functionalizable poly(ether ether ketone), PEEK, analogues were explored using varying percentages of 4,4’-difluorobenzophenone and either 3,5-difluorobenzophenone or 2,4-difluorobenzophenone as the electrophilic component in nucleophilic aromatic substitution polycondensation reactions with hydroquinone. PEEK analogues utilizing 3,5-difluorobenzophenone were carried out in a “one-pot” fashion and their properties were compared to the same materials prepared previously by a multi-step synthetic procedure. The use of 2,4-difluorobenzophenone led to completely new PEEK analogues. The polymers were characterized via NMR spectroscopy, Size Exclusion Chromatography, Thermogravimetic Analysis, and Differential Scanning Calorimetry. Molecular weight determinations showed the synthesized polymers to be of a variety …
Bioavailability And Transformation Of Silver Nanoparticles In The Freshwater Environment, Seth W. Brittle
Bioavailability And Transformation Of Silver Nanoparticles In The Freshwater Environment, Seth W. Brittle
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The proliferation of silver nanoparticles (AgNPs) in consumer products and industrial applications has generated many environmental concerns since the chemistry of silver changes at the nanoscale and the very properties that make them desirable – their unique reactivity – may pose environmental risks. This dissertation addresses these concerns from three different angles. First, freshwater crayfish is demonstrated as a potential benthic indicator of Ag pollution since Ag accumulation depends on the form of Ag. The uptake and distribution of Ag (from AgNPs or Ag+) in tissue samples were measured by inductively coupled plasma optical emission spectroscopy (ICP-OES). The hepatopancreas (1.5-17.4 …
Design And Application Of Facile Routes To N-Heterocycle Functionalized Poly(Arylene Ether)S, Abraham K. Kemboi
Design And Application Of Facile Routes To N-Heterocycle Functionalized Poly(Arylene Ether)S, Abraham K. Kemboi
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A series of 3,5-difluorinated systems, which are activated towards nucleophilic aromatic substitution (NAS) by the strongly electron withdrawing benzoxazole or benzothiazole groups, located meta to the fluorines were prepared and fully characterized. The monomers also carry various N-heterocyclic species on the non-fluorinated ring. The corresponding poly(arylene ether)s, some of which were copolymers with triphenylphosphine oxide-based monomers, were prepared via standard NAS polycondensation reactions. Incorporation of the monomers containing N-heterocycle units was determined by NMR spectroscopy. Characterization of the thermal properties was done using thermogravimetric analysis (TGA) and differential scanning (DSC). Most of the polymers displayed good film forming properties when …
Alkylenedioxy Containing Peek Polymers Containing Meta Linkages, James Uchenna Ohaeri
Alkylenedioxy Containing Peek Polymers Containing Meta Linkages, James Uchenna Ohaeri
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The oxyalkylene containing, meta linked monomers 1,2-bis(3-(4-fluorobenzoyl)phenoxy)ethane, 1,3-bis(3-(4-fluorobenzoyl)phenoxy)propane, 1,4-bis(3-(4-fluorobenzoyl)phenoxy)butane, 1,5-bis(3-(4-fluorobenzoyl)phenoxy)pentane can be prepared by a three-step process starting with the dialdehydes (1,2-bis(3-formylphenoxy)ethane, 1,3-bis(3-formylphenoxy)propane, 1,4-bis(3-formylphenoxy)butane and 1,5-bis(3-formylphenoxy)pentane, respectively). Polymerization of the monomers with bisphenol-A gave soluble, thermally stable amorphous poly(ether ether ketone)s. The polymers exhibited molecular weights of (Mw/Mn) (21,841/ 8721) g/mol, (21,195/ 7569) g/mol, (9,107/ 2819) g/mol and (12,990/ 4723) g/mol, respectively. Thermal analyses of the polymers revealed Tgs of 112º, 106º, 92º and 91º, respectively and 5% weight losses under a nitrogen atmosphere of 389º, 410º, 411º and 414º, respectively.
Determination Of Atmospheric Particulate Matter Composition In The Dayton Metro Area, Saagar Mahendra Patel
Determination Of Atmospheric Particulate Matter Composition In The Dayton Metro Area, Saagar Mahendra Patel
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Quartz filters from high-volume air samplers of particulate matter of a size less than 10 micrometers in diameter (PM10) located in Moraine and Yellow Springs, Ohio, were obtained from the Regional Air Pollution Control Agency and analyzed for levoglucosan, metals, and the EPA 16 priority polycyclic aromatic hydrocarbons (PAHs). Average concentration of levoglucosan increased as ambient temperature decreased. Winter concentrations of levoglucosan for Moraine and Yellow Springs were 39.41 ± 31.58 µg/g and 51.52 ± 27.44 µg/g, respectively, which is due to a greater amount of residential wood burning in the colder months. The concentration of biomass burning …