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Thermal And Electrochemical Characterization Of Cathode Materials For High Temperature Lithium-Ion Batteries In Ionic Liquids, Jodie R. Shoaf
Thermal And Electrochemical Characterization Of Cathode Materials For High Temperature Lithium-Ion Batteries In Ionic Liquids, Jodie R. Shoaf
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Finding a cathode material to operate a high-temperature Li-ion battery in the presence of an ionic liquid has become an attractive area of research. Three cathode materials, LiCoO2, Li4Ti5O12, and LiFePO4, were received from Electrochemical Systems Inc. of Knoxville, TN. Three ionic liquids were synthesized using a 1-alkyl-3-methylimidazolium (XMI+) cation, where the alkyl group was either ethyl, pentyl or hexyl, and contained a bis(pentafluoroethylsulfonyl)imide (Beti-) anion. The thermal and electrochemical properties of each ionic liquid, of each cathode material, and each combination of cathode material in the presence of ionic liquid were studied. All of the ionic liquids were found …
Functionalized, Semicrystalline Poly(Ether Ketone)S Via In Situ Modification Chemistry, Raghavendhar Reddy Kotha
Functionalized, Semicrystalline Poly(Ether Ketone)S Via In Situ Modification Chemistry, Raghavendhar Reddy Kotha
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AB3 monomer (3,4,5-Trifluoro-4'-hydroxybenzophenone) was used for polymerizations in order to mimic the combination of AB and AB2 monomers, and which has potential to facilitate concurrent polymerization and functionalization. 'Pre' and 'post' polymerization functionalization of the PEK system was done using phenol, 4-bromophenol, and 3/4-aminophenol. The solubility of the functionalized polymers was increased; and the crystallinity was decreased significantly compared to the corresponding unfunctionalized homopolymer. The polymers were characterized by 1H and 13C NMR spectroscopy, Gel Permeation Chromatography (GPC), Thermogravimetric Analysis (TGA), and Differential Scanning Calorimetry (DSC). DSC results showed that the crystallinity of the polymer was tuned by the amount …
Electrochemical Oxidation Of Ethanol In Ionic Liquids And Its Possible Use In Fuel Cells, Ashley M. Mason
Electrochemical Oxidation Of Ethanol In Ionic Liquids And Its Possible Use In Fuel Cells, Ashley M. Mason
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Electrochemical properties of EtOH in EMImBF4 ionic liquid were investigated and compared to the electrochemical properties of EtOH in 0.1M HClO4/H2O. As was shown earlier, oxidation of EtOH in HClO4/H2O involves formation of PtO on the electrode surface, which makes the electrode poisoned. We have found that the best procedure for removal of PtO from the Pt electrode is heating the electrode in concentrated H2SO4. Cyclic voltammograms obtained after cleaning several Pt electrodes conforms that this treatment gives clean Pt electrodes without any PtO. Electrochemical oxidation of EtOH in EMImBF4 ionic liquid show that is poisoning of Pt electrode by …
Skeletal Pathology Of Tibiotarsi In Chick Embryos Exposed To Platinum Group Metals By Micro-Raman Spectroscopy, Jennifer L. Monahan
Skeletal Pathology Of Tibiotarsi In Chick Embryos Exposed To Platinum Group Metals By Micro-Raman Spectroscopy, Jennifer L. Monahan
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Platinum group metals (PGMs) have been shown to accumulate in various tissues of organisms but their toxicity is not well-known. Raman spectroscopy is a powerful analytical technique that enables direct and non-destructive chemical characterization of bone tissues. PGMs were injected into chick embryos in the following concentrations: 0.1, 1.0, 5.0, or 10.0 ppm solutions of Pt(IV), Rh(III), Pd(II) or PGMs mixtures (0.1 ppm or 1.0 ppm of each metal). The micro-Raman maps recorded on the paraffin embedded tibiotarsus cross-sections showed significant changes in the chemical composition and structure of the bone tissue as a result …
Temperature And Ph Responsive Polyethylenimine Systems As Potential Nonviral Gene Vectors, S. Chad Skidmore
Temperature And Ph Responsive Polyethylenimine Systems As Potential Nonviral Gene Vectors, S. Chad Skidmore
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Modified HPEI was used to determine if the LCST could be controlled by varying multiple variables, including: percent modification, pH, salt solution concentration, and weight percent. Two modifications were done with butylene oxide (Butox) and isobutyryl amide (IBAm). Specifically, 100% (HPEI-Butox1.00)butoxylated and 10% (HPEI-IBAm0.10), 54% (HPEI-IBAm0.54), and 70% (HPEI-IBAm0.70) amidated samples were synthesized. Additionally, HPEI-IBAm0.54 was further modified with hydroxyl ethyl groups (HPEI-IBAm0.54 Eox0.46) and ethyl groups (HPEI-IBAm0.54-Et0.44). The LCSTs of all amidated systems were below body temperature, 37 °C, at pH = 7.4. This indicates an ability of these systems to be used as a vector for gene delivery. …
Novel Synthesis Of Polyhydrogenated Fullerenes, Angela Campo
Novel Synthesis Of Polyhydrogenated Fullerenes, Angela Campo
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Hydrogenated fullerenes are of interest as a starting material in metal fulleride synthesis. By reacting C60H2 with various metals, alloyed metal fullerides could be produced. To achieve this goal, first a reliable synthesis of C60H2 must be determined. C60H2 is difficult to synthesis exclusively; C60H4 and C60H6 are also produced. Reduction of C60 with NaBH4 produced a mixture of products as well as excessive unreacted C60. Attempts to modify this reaction to achieve C60H2 exclusively were unsuccessful. A …
Small Molecule Caspase Inhibitors Using Isatin And Oxindole Scaffolds And A Combinatorial Approach, Hagar Mahmoud Abdallah
Small Molecule Caspase Inhibitors Using Isatin And Oxindole Scaffolds And A Combinatorial Approach, Hagar Mahmoud Abdallah
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Quinolyl-valyl-O-methylaspartyl-[2,6-difluorophenoxy]-methyl ketone (Q-VD-OPh) is a next generation broad spectrum caspase inhibitor, the effectiveness and reduced toxicity of which can be partially attributable to the carboxyterminal O-phenoxy group as well as the amino terminal quinolyl groups. We seek to incorporate some of these unique recognition elements onto small molecule derived protease inhibitors with drug like properties. Specifically, heterocyclic scaffolds such as isatins and oxindoles. Thus, isatins bearing electron withdrawing groups on C-5 and 2,6-difluorobenzyl moieties have been prepared by analogy to the well studied N-substituted 5-pyrrololidinylsulfonyl isatins. Moreover, 3-benzylidene oxindole derivatives bearing these structural motifs have also been prepared and their …
Exploration Using Reaction Temperature To Tailor The Degree Of Order In Micro-Block Copolymer Proton Exchange Membranes, John Quentin Buquoi Iii
Exploration Using Reaction Temperature To Tailor The Degree Of Order In Micro-Block Copolymer Proton Exchange Membranes, John Quentin Buquoi Iii
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The ability to control the self-assembly of sulfonated poly(arylene ether) sulfones (s-PAESs) was explored by tailoring rate coefficients, via temperature, in an A2 + B2 + B2' Nucleophilic Aromatic Substitution (SNAr) approach. The reactivity of various electrophilic sites were studied and tuned, via temperature control, to elicit a range of more ordered and disordered polymers of equivalent monomeric composition. These polymers were characterized by 1H and 13C NMR spectroscopy and found to have highly disordered polymer configuration at higher temperatures while having a more regular configuration at lower temperatures.
Towards The Total Synthesis Of Haplomyrtin, Nora Ellen Hunter
Towards The Total Synthesis Of Haplomyrtin, Nora Ellen Hunter
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Haplomyrtin, a 1-aryl-2,3-naphthalide lignan obtained from Turkish Haplophyllum myrtifolium and Haplophyllum telephioides offers a number of synthetic challenges with the incorporation of two aromatic hydroxyl groups at positions C4 and C7 on the naphthalene ring system and regiospecific condensation of the γ-lactone ring. Improvements towards the total synthesis of haplomyrtin were pursued with commercially available vanillin and piperonal in a total of 8 separate steps. All steps have excellent reproducibility. This strategy includes bromination of protected vanillin to yield 2-(4-(4-methoxybenzyloxy)-2-bromo-5-methoxyphenyl)-1,3-dioxolane and 2-(4-(benzyloxy)-2-bromo-5-methoxyphenyl)-1, 3-dioxolane in 48% and 88% yield respectively, and incorporation of the fully functionalized pendant aryl ring through a …
1-Alkyl-3-Methylimidazolium Bis(Trifluoromethylsulfonyl)Imide Based Ionic Liquids: A Study Of Their Physical And Electrochemical Properties, Charles William Dutton
1-Alkyl-3-Methylimidazolium Bis(Trifluoromethylsulfonyl)Imide Based Ionic Liquids: A Study Of Their Physical And Electrochemical Properties, Charles William Dutton
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Ionic liquids are of interest because of their electrochemical and thermal properties and their possible use as electrolytes in batteries. In this work five ionic liquids were synthesized. They consisted of a 1-alkyl-3-methylimidazolium (RMI+) cation, where the alkyl group was ethyl, propyl, butyl, pentyl, or hexyl, and a bis(tri-fluoromethylsulfonyl)imide (NTf2-)anion. The decomposition temperatures, melting points, conductivities, viscosities, densities, absorption and desorption of water, diffusion coefficients, and electrochemical properties were studied. It was found that these ionic liquids were thermally stable up to ~310 °C, and that EMINTf2 had a melting point at -18.26 °C. Conductivities …
A Comparison Of Atmospheric Pahs In Pine Needles And High-Volume Sampler Filters In The Dayton Metro Area, Timothy A. Tomashuk
A Comparison Of Atmospheric Pahs In Pine Needles And High-Volume Sampler Filters In The Dayton Metro Area, Timothy A. Tomashuk
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Samples of filters from High-volume (HiVol) samplers of particulate matter (PM) with a size of 10 micrometers or less were deployed for five months in Moraine and Yellow Springs, OH, by the Regional Air Protection Control Agency and analyzed for the Environmental Pollution Agency (EPA) 16 polycyclic aromatic hydrocarbons (PAHs). Pine needles on trees near the HiVol samplers were also collected and analyzed for a comparison with the active samplers to estimate atmospheric PAH concentrations. Pine needles were found to collect lower molecular weight (LMW) compounds far more than HiVol sampler and thus their profiles shown to compliment the HiVol …
Electrochemical Deposition Of Molybdenum And Tungsten From Trinuclear Metal Clusters (M3O2(Oac)6(H2O)3(Cf3So3)2) In 1-Ethyl-3-Methylimidazolium Tetrafluoroborate Ionic, Charles Woods
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Electrochemical properties of Mo2WO2(O2CCH3)6(H2O)3(CF3SO3)2 and W3O2(O2CCH3)6(H2O)3(CF3SO3)2 clusters in 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIBF4) ionic liquid was investigated. Cyclic voltammograms using a platinum electrode indicated that deposition of metal had occurred. Constant potential electrolysis of Mo2WO2(O2CCH3)6(H2O)3(CF3SO3)2 at -1.9 V using a platinum foil electrode …
Routes To Acylated Sydnones Utilizing Microwave Chemistry, Amber C. Rumple
Routes To Acylated Sydnones Utilizing Microwave Chemistry, Amber C. Rumple
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In the present work, microwave chemistry was utilized to improve and optimize two methods for the acylation of sydnones. Whereas before, 4-acyl-3-arylsydnones could be synthesized by the use of Friedel-Crafts reactions utilizing either Montmorillonite K-10 or bismuth(III) triflate/lithium perchlorate as catalysts in moderate to good yields after long reaction times, with the introduction of microwave chemistry 4-acyl-3-arylsydnones can be synthesized in good to excellent yields in much shorter times. A previous method using Montmorillonite K-10 allowed for a variety of 4-acetyl-3-arylsydnones to be synthesized thermally in moderate to good yields after at least 24 hours. This method was extended in …
Routes To Sydno[3,4-A]Quinoxalines, Erik Dihrkop
Routes To Sydno[3,4-A]Quinoxalines, Erik Dihrkop
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In the present work, the reactivity of alkyl and aryl sydnoquinoxalines was studied. Using a previously developed method, triphenylphosphine-2-(3-sydnonyl)phenylimide was prepared in a two-step process via a diazotization / azidation process of 3-(2-aminophenyl)sydnone, followed by treatment with triphenylphosphine. Due to the inability to achieve previously reported yields, a new, one-step method using Mitsunobu conditions was employed to synthesize the iminophosphorane in a good yield. A similar, brominated iminophosphorane was synthesized using the same conditions in a good yield. Treatment of both the brominated and non-brominated iminophosphoranes with alkyl and aryl isocyanates or isothiocyanates in an aza-Wittig process, gave the corresponding …