Index Catalog // ScholarsArchive@OSU

Influence of Asian and Western U.S. Urban Areas and Fires on the Atmospheric Transport of PAHs, PCBs, and FTOHs in the Western U.S.

Creator:: Primbs, Toby, Piekarz, Arkadiusz, Wilson, Glenn, Schmedding, David, Higginbotham, Carol, Field, Jennifer, and Simonich, Staci
Abstract:: Atmospheric measurements of semivolatile organic compounds (SOCs) were made at Mt. Bachelor Observatory (MBO), located in Oregon’s Cascade Range, to understand the trans-Pacific and regional transport of SOCs from urban areas. High volume air sampling (~644 m³ for 24 hour periods) of both the gas and particulate phases was conducted...
Resource Type:: Article

Synthesis of α-Ketoester- and α-Hydroxyester-Substituted Isoindazoles via the Thermodynamic Coarctate Cyclization of Ester-Terminated Azo-Ene-Yne Systems

Creator:: McClintock, Sean P., Forster, Nathan, Herges, Rainer, and Haley, Michael M.
Abstract:: The synthesis of isoindazoles bearing α-ketoester and α-hydroxyester groups via the coarctate cyclization of ester terminated azo-ene-yne precursors is described. Whereas previous studies on isoindazole formation have shown the reaction to proceed through a kinetic coarctate pathway, functionalization of the terminal acetylene with a methyl ester sufficiently stabilizes the carbene...
Resource Type:: Article

Influence of Asian and Western United States Agricultural Areas and Fires on the Atmospheric Transport of Pesticides in the Western United States

Creator:: Primbs, Toby, Wilson, Glenn, Schmedding, David, Higginbotham, Carol, and Simonich, Staci Massey
Abstract:: Historic and current use pesticides (HUPs and CUPs), with respect to use in the United States and Canada, were identified in trans-Pacific and regional air masses at Mt. Bachelor Observatory (MBO), a remote high elevation mountain in Oregon’s Cascade Range located in the United States, during the sampling period of...
Resource Type:: Article

Mass spectrometric studies on peptides and proteins : conformations of Escherichia coli Thioredoxin and its alkylated adducts studied by hydrogen/deuterium exchange and HPLC-electrospray ionization mass spectrometry

Creator:: Kim, Moo-young
Abstract:: E. coli thioredoxin (TRX) was modified by the episulfonium ion derived from S-(2-chloroethyl)glutathione (CEG) or S-(2-chloroethyl)cysteine (CEC). The alkylation site was located at Cys-32, which was confirmed by tandem mass spectrometry. Two forms of native TRX, Oxi- and Red-TRX, and two modified TRXs, GS- and Cys-TRX, were examined by hydrogen/deuterium...
Resource Type:: Dissertation

Mass spectrometric analysis of proteins and peptides : elucidation of the folding pathways of recombinant human macrophage colony stimulating factor beta

Creator:: Zhang, Yuan Heidi
Abstract:: Recombinant human macrophage colony stimulating factor beta (rhm-CSFβ) is a glycoprotein that stimulates the proliferation, differentiation and survival of cells belonging to the monocyte-macrophage lineage. It contains nine inter-subunit and intra-subunit disulfide bonds and represents an excellent model system for studying disulfide bond formation during protein folding because the assembly...
Resource Type:: Dissertation

Photochemistry of molecules oriented with a uniform electric field

Creator:: Castle, Karen J.
Resource Type:: Dissertation

Total synthesis of (-)-7-epicylindrospermopsin

Creator:: Hansen, Joshua D.
Abstract:: The first asymmetric synthesis of (-)-7-epicylindrospermopsin via intramolecular nitrone cycloaddition is described. The synthesis utilized a convergent approach to prepare the cycloaddition precursor 176, which was assembled by condensation of hydroxylamine 175 with aldehyde 145. Hydroxylamine 175 was synthesized from ethylene glycol (166) in seven steps. Aldehyde 145 was completed...
Resource Type:: Dissertation

Delocalization in cationic, carbene, and radical intermediates in some bridged polycyclic systems

Creator:: Dacres, Jelena Estelle
Resource Type:: Dissertation

Development and application of an analytical technique for the determination of methylmercury compounds in environmental samples based on isolation by distillation, followed by purge-and-trap sample concentration and GC/MS separation and detection, after aqueous phase ethylation with sodium tetraethylborate

Creator:: Rice, William R.
Abstract:: An analytical technique has been developed for the determination of methylmercury compounds in environmental samples. The technique is based on a two-stage procedure. In the first stage, methylmercury compounds are isolated from the sample matrix as methylmercury chloride (MeRgCl) by distillation. The distillation procedure is based on a series of...
Resource Type:: Masters Thesis

Electroluminescent and photoluminescent phosphor development and a facile approach to synthesis of refractory silicates at low temperatures

Creator:: Clark, Benjamin L.
Resource Type:: Dissertation

Novel monolithic columns for microscale liquid chromatography and capillary electrochromatography

Creator:: Chirica, Gabriela S.
Abstract:: The challenges prompted by miniaturization of chromatographic systems have led scientists to explore new avenues in the synthesis of stationary phases. Packed capillary columns have found limited application in routine analysis due to a number of technical difficulties, most of which are attributable to the frits. New column designs insure...
Resource Type:: Dissertation

Negative thermal expansion in AOMO₄ compounds

Creator:: Amos, Tammy G.
Resource Type:: Dissertation

The role of iron-oxides in U(VI) adsorption and the kinetics of contaminant organic reduction

Creator:: Logue, Brian A.
Abstract:: Contaminant transport in ground water is an important environmental process that affects a host of natural systems. Transport of contaminants is affected by many processes, including aqueous complexation, adsorption, and redox reactions. One of the most important components of an aquifer that controls transport is iron-oxide. In this study, the...
Resource Type:: Dissertation

A contribution to the development of wide band-gap nonlinear optical and laser materials

Creator:: Stone-Sundberg, Jennifer L.
Abstract:: The primary focus of this work is on examining structure-property relationships of interest for high-power nonlinear optical and laser crystals. An intuitive and simply illustrated method for assessing the nonlinear optical potential of structurally characterized noncentrosymmetric materials is introduced. This method is applied to materials including common quartz and tourmaline...
Resource Type:: Dissertation

Threshold ionization spectroscopy of metal clusters and metal-ligand complexes

Creator:: Peng, Xianzhao
Abstract:: In this dissertation, we describe a spectroscopic study of metal clusters and metal-ligand complexes using pulsed field ionization zero kinetic energy (PFI-ZEKE) photoelectron spectroscopy and mass analyzed threshold ionization (MATI) spectroscopy. Vibrational resolved spectra of sodium dimer, Na•NH₃, Na•(NH₃)₂ are presented. These spectra provide a direct measurement of the ionization...
Resource Type:: Dissertation

Intercalation, exfoliation, and nanocomposites of layered inorganic compounds

Creator:: Sukpirom, Nipaka
Abstract:: The melt intercalation of poly(ethylene oxide) (PEO) between layers of MoO₃ and MPS3 (M=Mn,Cd) is obtained by heating the ground mixture and LiₓMoO₃, KₓMn₁-ₓ/₂PS₃, or KCd₁-ₓ/₂PS₃. The products are characterized by powder X-ray diffraction (XRD). Below the melting temperature of PEO (66 °C), intercalation rates and yields are low. By...
Resource Type:: Dissertation

Evaluation of sampling/preconcentration techniques and pyridine derivative reagents for fluorometric determination of chloroform and TCE in water

Creator:: Prayoonpokarach, Sanchai
Abstract:: A direct purge technique was developed for the determination of chloroform or trichloroethylene (TCE) in water samples. These volatile organic solvents are transferred from the water sample to a reagent where they are trapped and react to form products (Fujiwara chemistry) that are monitored fluorometrically. Chloroform in a water sample...
Resource Type:: Masters Thesis

Advanced studies on the biosynthesis of the streptolidine moiety of streptothricin F

Creator:: Jackson, Michael D.
Resource Type:: Dissertation

Natural product synthesis via cyclobutanes : part I, Asymmetric synthesis of (+)-byssochlamic acid, part II, An approach to the nootropic agent huperzine A

Creator:: Kim, Jungchul
Abstract:: PART I. Asymmetric syntheses of both natural (+)- and nonnatural (-)-byssochlamic acid via a [2+2] photoaddition-cycloreversion strategy are described. X-ray crystallographic analysis of the cyclohexylamine salt 99 showed that the structure of the monomethyl ester 100 from esterase hydrolysis of 44 was originally misassigned as 56. The enantiomeric relationship of...
Resource Type:: Dissertation

Novel approaches to enhancing selectivity and efficiency in microscale liquid chromatography

Creator:: Vallano, Patrick T.
Abstract:: For a number of reasons, miniaturization of chromatographic columns has been a general trend over the past three decades. Methods designed to enhance selectivity and efficiency can offer improved separation power and speed, expanding on the advantages of miniaturized columns. This dissertation describes novel approaches in this direction, focusing on...
Resource Type:: Dissertation

Synthesis of marine natural products. part I, Cryptophycins-1, -3, -4, -24, and -29, part II, Polycavernoside A

Creator:: Robarge, Lonnie A.
Resource Type:: Dissertation

Mechanistic studies on Re(V) mediated C-O bond transformations

Creator:: Zhuravlev, Fedor
Abstract:: In situ, reduction of Cp*ReO₃ by PPh₃ to form (Cp*ReO)₂(μ-O)₂ allows catalytic deoxygenation of epoxides, however, conproportionation between Reⱽ and Reⱽᴵᴵ species to form clusters of ((Cp*Re)₃(μ-O)₆}²⁺(ReO₄⁻)2 and new compound {(Cp*Re)₃(μ²-O)₃(μ³-O⁾³ReO₃}⁺(ReO₄⁻) leads to removal of rhenium from the catalytic cycle and loss of activity, The epoxide deoxygenation mediated by (Cp*ReO)₂(μ-O)₂...
Resource Type:: Dissertation

High resolution spectroscopy of sulfur trioxide and carbon suboxide

Creator:: Masiello, Tony
Abstract:: High resolution spectroscopy was used to study the properties of two simple polyatomic molecules, sulfur trioxide, SO₃, and carbon suboxide, C₃O₂. The fundamental modes and several hot bands of the ¹⁸O isotopic fonns of SO₃ (³²S¹⁸O₃ and ³⁴S¹⁸O₃) have been investigated using both infrared spectroscopy and coherent anti-Stokes Raman scattering...
Resource Type:: Dissertation

Applications of nonlinear raman spectroscopy

Creator:: Melin, Stéphanie
Abstract:: Two nonlinear optical experiments are presented in which the third-order electronic susceptibility of molecules is used to generate Raman signals. The first one uses a single 532 nm beam from a Nd:YAG laser to produce Stimulated Raman Scattering in benzene and deuterated benzene. With a simple experimental set-up, stimulated emission...
Resource Type:: Masters Thesis

Synthesis and study of oxides and chalcogenides : thin films and crystals

Creator:: Park, Sangmoon
Abstract:: Several types of solid-state inorganic materials are prepared and characterized. By using the SILAR (Successive Ionic Layer Adsorption and Reaction) deposition method in conjunction with hydrothermal dehydration both low-temperature deposition and crystallization of oxide thin films are achieved. Various aspects of new transparent p-type materials are studied by examining both...
Resource Type:: Dissertation

Mass spectrometric analysis of UV-crosslinked protein-nucleic acid complexes

Creator:: Doneanu, Catalin E.
Abstract:: The DNA-binding domains of E. coli uracil-DNA glycosylase (Ung) and human replication protein A (hRPA) were studied using a general protocol developed in our laboratory for probing protein-DNA interactions. The procedure involves purification and mass spectrometric analysis of the nucleopeptide-products of a tryptically digested UV-crosslinked protein-nucleic acid complex. In the...
Resource Type:: Dissertation

Determination of fluorinated alkyl substances in aqueous systems

Creator:: Schultz, Melissa M.
Abstract:: Fluorinated alkyl substances, which can be persistent, toxic, and bioaccumulative, have been quantitated in many densely populated and remote regions, including in air, surface waters, groundwater, and biota; however, little is known about their transport or behavior in the environment. Wastewater effluent is one of the principal routes for introducing...
Resource Type:: Dissertation

Rhenium-catalyzed oxygen-atom transfer reactions : mechanism and applications

Creator:: Brown, Eric C.
Abstract:: In situ reduction of hydrido-tris-(3,5-dimethylpyrazolyl)borato(trioxo) rhenium(V) with triphenylphosphine or triethylphosphite leads to a reactive rhenium(V) species that catalytically deoxygenates epoxides at 75-105°C. The reaction is stereospecific, except for trans- and cis-butene oxide which formed minor amounts of the opposite isomer. A variety of different functional groups were tolerated and even...
Resource Type:: Dissertation

Synthesis, characterization, and reactivity of rhenium dithiodiolate and monothiodiolate complexes

Creator:: Chuawong, Pitak
Abstract:: The rhenium dithiodiolate, Hydrido-tris-(3 ,5-dimethyl- 1 -pyrazol yl) borato(ethane- 1 ,2-dithiodiolato)(oxo)rheni um(V), and Hydrido-tris-(3 ,5-dimethyl- 1 -pyrazolyl)borato(phenylethanedithiodiolato)(oxo)rhenium(V), were synthesized by reductive cyclocondensation of alkane-1,2-dithiols with Tp'Re0₃ in a one pot fashion. The rhemium monothiodiolate, Hydrido-tris-(3 ,5-dimethyl- 1 -pyrazolyl) borato(ethane- 1 ,2-monothiodiolato)(oxo)rhenium(V), and Hydrido-tris-(3 ,5- dimethyl- 1 -pyrazolyl)borato(propanemonothiodiolato)(oxo)rhenium(V), were also synthesized...
Resource Type:: Masters Thesis

A new trigonal huntite material and subgroup relationships between crystallographic space groups

Creator:: Hruschka, Michael Archimedes and Hruschka, Michael A.
Abstract:: The use of an adjacency matrix to determine distant (not maximal or minimal) subgroup and supergroup relationships between crystallographic spacegroup types is described. Full lists of space-group types that are supergroups and subgroups for every space-group type were compiled. A list of the space-group types connected to each space-group type...
Resource Type:: Dissertation

Synthesis and structure of new transition metal containing bismuth oxides

Creator:: Xun, Xiumei
Abstract:: Exploratory synthesis is the discovery of new compounds with interesting structures and properties. The subject of this thesis is exploratory synthesis of bismuth containing oxides. Bismuth containing oxides have many interesting properties, which are ionic conductivity, ferromagnetism, superconductivity, ferroelectricity, ferroelasticity and catalytic. These properties are closely related to their specific...
Resource Type:: Dissertation

High resolution spectroscopic studies of ³²S¹⁶O₃ and ³⁴S¹⁶O₃

Creator:: Barber, Jeffrey
Abstract:: The two sulfur isotopomers of sulfur trioxide, ³²S¹⁶O₃ and ³⁴S¹⁶O₃, have been studied via high resolution infrared and Coherent anti-Stokes Raman (CARS) spectroscopy. The v₁ symmetric SO stretching Q-branches observed by the latter are quite different, being especially complex for ³²S¹⁶O₃ Understanding this band structure required analysis of infrared-active hot...
Resource Type:: Dissertation

Measuring in situ reductive dechlorination rates in trichloroethene-contaminated groundwater

Creator:: Hageman, Kimberly J.
Abstract:: Trichloroethene (TCE) is the most frequently detected organic contaminant in groundwater, is classified as a probable human carcinogen, and exhibits toxicological effects on the human endocrine, immune, developmental, and reproductive systems. While significant research efforts have been devoted to the development of strategies for remediating TCE-contaminated groundwater, their advancement is...
Resource Type:: Dissertation

Surface composition and orientation of room temperature ionic liquids

Creator:: Law, George
Abstract:: In this thesis, we investigated the surface composition and orientation of both pure room-temperature ionic liquids (Ils) and binary mixtures of the ILs of the type consisting of the 1-alkyl-3-methylimidazolium ([C[subscropt n]mim]⁺, n=4, 8, and 12) cation coupled with either [PF₆]⁻, [BF₄]⁻, [Cl]⁻, or [Br]⁻. The surfaces of the ILs...
Resource Type:: Dissertation

Theory of negative thermal expansion

Creator:: Tao, Ju Zhou
Abstract:: Two framework oxide materials of the MO₃ network type have been synthesized and structurally characterized by synchrotron and X-ray powder diffraction and the Rietveld method in the temperature range 25~500 K. The results show one of them to be a low thermal expansion material. Theoretical studies of negative thermal expansion...
Resource Type:: Dissertation

Total synthesis of indole alkaloids: pt. 1. Asymmetric synthesis of (-)-ibogamine. pt. 2. An approach toward the synthesis of koumine

Creator:: Choi, Younggi
Abstract:: PART I. The preparation of (-)-ibogamine (1) in fourteen steps from benzoquinone and in 10% overall yield is a powerful illustration of the value of the asymmetric Diels-Alder reaction as a starting point in a multistep synthesis. All four cycloadducts, 70, 77, 84 and 96, obtained with the (S)-BINOL-TiCl₂ complex...
Resource Type:: Dissertation

Natural and semi-synthetic compounds with biocidal activity against arthropods of public health importance

Creator:: Khasawneh, Mohammad A.
Abstract:: This study identified new compounds with pest control activities. The two sources of candidates that were followed here were the main heartwood extract of Alaska Yellow Cedar (AYC) constituents and several semi-synthetic counterparts. Five compounds were isolated and identified for the first time in AYC heartwood in this research: two...
Resource Type:: Dissertation

Studies toward the total synthesis of phorboxazole A

Creator:: Kuntiyong, Punlop
Abstract:: Studies toward the total synthesis of a highly potent cytotoxic marine natural product, phorboxazole A, were conducted and resulted in a route to an advanced intermediate, C4-C32, for this purpose. A key feature of our approach is the stereoselective synthesis of two cis-2,6-disubstituted tetrahydropyrans present in the macrolide portion of...
Resource Type:: Dissertation

Development and evaluation of sampling techniques, instrumentation, and pyridine derivative reagents for fluorometric determination of chloroform and TCE in water with a portable fluorometer

Creator:: Prayoonpokarach, Sanchai
Abstract:: A novel, portable, filter fluorometer was developed for the determination of chloroform and TCE at environmentally-relevant levels when coupled with improved sampling techniques and reagents. Reagents selective for the TCE or chloroform convert these toxic species into fluorescent species that can be monitored. The fluorometer is based on LED excitation...
Resource Type:: Dissertation

Proteomic approach to the analysis of DNA-binding proteins using mass spectrometry

Creator:: Stapels, Martha Degen
Abstract:: In proteomic studies, separate experimental protocols have been necessary to identify proteins, determine their function, and predict their three-dimensional structure. In this study, a function-based separation of proteins was conceived to fractionate proteins prior to enzymatic digestion. In the initial demonstration of this technique, a DNA substrate was used to...
Resource Type:: Dissertation

Synthesis of furanoeremophilane sesquiterpenoids

Creator:: Shanmugham, Meenakshi Sundaram
Abstract:: Two approaches to the tricyclic core of the furanoeremophilane sesquiterpenoids are described. The first approach entails a projected Diels-Alder/retro Diels-Alder reaction of an acetylenic oxazole 64. Construction of the pivotal aldehyde 67 commenced from ketone 68. The acetyenic moiety was then introduced via a Felkin-Ahn addition of lithiopropyne to aldehyde...
Resource Type:: Dissertation

Atmospheric transport of anthropogenic semi-volatile organic compounds to the Olympic Peninsula of Washington State

Creator:: Killin, Robert K.
Abstract:: Ambient high-volume (hi-vol) air samples were collected between March 15th and May 30th 2002, at Cheeka Peak Observatory (CPO), located on the tip of the Olympic Peninsula, Washington State. This sampling campaign was in conjunction with the 2002 Inter-Continental Transport and Chemical Transformation (ITCT 2K2) Campaign and the Photochemical Ozone...
Resource Type:: Masters Thesis

Active site studies and design of ligands for affinity column separation of 2,5-dihydroxyacetanilide epoxidase (DHAE) I and II

Creator:: Allen, Scott E.
Abstract:: A series of compounds, 7-8 and 20-25, were tested as competitive inhibitors of 2,5-dihydroxyacetanilide epoxidase I (DHAE I) and DHAE II. A Hammett plot was constructed for each enzyme to determine the effect of electron density on inhibition. DHAE I gave a linear, highly correlated plot (r²=0.91) that signifies the...
Resource Type:: Dissertation

Studies on nitrogen containing secondary metabolites from terrestrial and marine origin

Creator:: Barrios Sosa, Ana Carolina
Abstract:: PART I. A deuterium exchange analysis of 2,5-dihydroxyacetanilide (5) in the absence and presence of DHAE II was performed to test the nucleophilicity of the substrate in the absence and presence of catalyst. In addition, inhibition studies using 1,4-dihydroxybenzene were performed to determine the role that the N-acetyl side chain...
Resource Type:: Dissertation

Direct atom transfer vs. ring expansion in reaction of rhenium oxo complexes with cyclooctene epoxides and episulfides

Creator:: Khownium, Kriangsak
Abstract:: The rhenium (V) complex Tp'ReO₂ (Tp' = hydrido-tris-(3,5- dimethylpyrazolyl)borate), generated in situ from PPh₃ reduction of Tp'Re0₃, reacts with small ring heterocycles such as epoxides and episulf ides. The strained trans-cyclooctene ring provides an unusual thermodynamic bias against direct atom transfer, but trans-cyclooctene oxide still produces substantial amounts of trans-cyclooctene....
Resource Type:: Masters Thesis

Designing chiral rhenium (VII) trioxo complexes

Creator:: Juniku, Rajan B.
Abstract:: The epoxide deoxygenation reaction is formally the reverse of theepoxidation reaction. Compared to epoxidation, which has reached its fullmaturity, epoxide deoxygenation has not been as intensively developed.Among the few deoxygenation reagents, a handful are catalytic in a metalcomplex, show high stereospecificity and operate under mild conditions. Acommon feature of all...
Resource Type:: Masters Thesis

The development and characterization of miniature spectrometers for measuring the redox status of environmental samples

Creator:: Cantrell, Kevin
Abstract:: A spectrometer, here denoted a Simple, Low-power, Inexpensive. Microcontroller-based or SLIM spectrometer. was developed that exploits the small size and low cost of solid-state electronic devices. This approach results in customizable spectrometers that are considerably less expensive and smaller than traditional instrumentation. The performance of the SLIM spectrometer was evaluated...
Resource Type:: Dissertation

Electronic spectroscopy of biological relevant species and their complexes with solvent molecules

Creator:: He, Yonggang
Abstract:: In this dissertation, I present electronic spectroscopy of a few biologically relevant species and their complexes with solvent molecules in the gas phase using a variety of techniques, including resonantly enhanced multiphoton ionization (REMPI), laser induced fluorescence (LIF), and zero kinetic energy (ZEKE) photoelectron spectroscopy. My work on several methylated...
Resource Type:: Dissertation

In situ transformation of toluene and xylene to benzylsuccinic acid analogs in contaminated groundwater

Creator:: Reusser, Dominik E.
Abstract:: The rate of removal of benzene, toluene, ethylbenzene and the xylene isomers (BTEX) from contaminated groundwater is needed to design remediation processes. Benzylsuccinic acid (BSA) and methyl-benzylsuccinic acid (methyl BSA) are unambiguous metabolites of anaerobic BTEX biodegradation. An analytical method for quantitative determination of BSA in groundwater samples was developed....
Resource Type:: Masters Thesis

Synthesis and study of transparent p- and n-type semiconductors and luminescent materials

Creator:: Park, Cheol-Hee
Abstract:: New transparent p- and n-type semiconductors and luminescent materials have been prepared and characterized. Synthesis, structures, optical and electrical properties of new chalcogenide fluoride p-type transparent semiconductors MCuQF (M=Ba, Sr; Q=S, Se, Te) are described. Band-gap tuning and improvement in conductivity through p-type doping are demonstrated in the family. The...
Resource Type:: Dissertation

RNA and DNA aptamers as affinity stationary phases for liquid chromatography and capillary electrochromatography

Creator:: Clark, Stacey L.
Abstract:: Due to a number of disadvantages associated with the use of antibodies as affinity stationary phases, researchers have recently began to explore the use of RNA and DNA aptamers for use as affinity stationary phases. These molecules have been shown to be a viable choice for applications in many methods...
Resource Type:: Dissertation

Monolithic sorbents for microscale separations

Creator:: Doneanu, Angela
Abstract:: Over the last decade, the miniaturization of analytical systems has become an increasingly important and interesting research area. Miniaturized systems offer many advantages, including reduced reagent and sample consumption, shorter analysis times, portability and disposability. This dissertation describes novel approaches in this direction, focusing on two areas: the miniaturization of...
Resource Type:: Dissertation

Synthesis of epothilones and epothilone analogues

Creator:: Sundermann, Kurt F.
Abstract:: A convergent synthesis of epothilone B that generates all seven of its asymmetric centers in a completely stereoselective fashion has been completed. Key reactions include an anti-Felkin aldol condensation to set the C6 and C7 stereochemistry, a directed α-hydroxylation to install the C15 (S)-hydroxyl substituent, and a Wittig condensation to...
Resource Type:: Dissertation

Asymmetric synthesis of cyclopropanes via a "zipper reaction"

Creator:: Lincoln, Christopher M.
Abstract:: The rearrangement of a homoallyl cation to a cyclopropylcarbinyl cation is thought to play a role in the biogenesis of a variety of cyclopropane-containing natural products,¹ a hypothesis which has previously led to the design of successful biomimetic syntheses of several natural products.² The strategy underlying this approach to cyclopropane...
Resource Type:: Dissertation

Quantifying in situ β-glucosidase and phosphatase activity in groundwater

Creator:: Radakovich, Karen M
Abstract:: Enzymes play an important role in the environment, they breakdown natural-occurring and anthropogenic molecules so that they can be transported into cells and utilized. Enzyme assays are routinely used in soil science and oceanography to measure the activities of specific processes and to serve as general indicators of microbial activity....
Resource Type:: Dissertation

Studies towards the total synthesis of (-)-gymnodimine

Creator:: Wang, Guoqiang
Abstract:: Studies towards the total synthesis of (-)-gymnodimine (1), a marine neurotoxin with a unique molecular architecture and pronounced biological activity, are described. These studies resulted in a convergent approach to the advanced intermediate 315, containing the C3-C32 section of 1. Two synthetic routes were developed to construct the tetrahydrofuran subunit...
Resource Type:: Dissertation

Mass spectrometric analysis of bovine neurofilament proteins NF-L, NF-M, and NF-H : peptide mapping, phosphorylation and alkylation site identification

Creator:: Mixon, April E.
Abstract:: Neurofilament proteins are intermediate filaments found in the neuronal cytoskeleton. Phosphorylation of these proteins is considered important for the assembly and stability of the filaments. Accurate molecular weights have been difficult to measure, largely because the high degree of phosphorylation results in M[subscript r]'S that are significantly greater than dictated...
Resource Type:: Masters Thesis

Monitoring redox conditions with redox indicators during microbial reductive dechlorination in microcosms and bioaugmented columns

Creator:: Ruiz-Haas, Peter A.
Abstract:: New methods, sensors, and devices based on redox indicators were developed to monitor redox conditions in anoxic and anaerobic laboratory systems and the subsurface environment. The primary application was monitoring redox conditions during the dechlorination of tetrachioroethene (PCE) to ethene (ETH) in packed columns and microcosm bottles containing an enriched...
Resource Type:: Dissertation

Synthesis, characterization, and structural modeling of graphite intercalation compounds with fluoroanions

Creator:: Yan, Wei
Abstract:: New synthetic strategies have been investigated for nano-dimensioned graphite particles or even isolated graphene sheets. One approach is to prepare graphite intercalation compounds (GICs) with low layer charge density and appropriate gallery height, followed by the colloidal dispersion or exfoliation of the resulting GICs. A series of anions has been...
Resource Type:: Dissertation

Dielectric and polarization experiments in high loss dielectrics: A word of caution

Creator:: Maglione, M. and Subramanian, M. A.
Abstract:: The recent quest for improved functional materials like high permittivity dielectrics and/or multiferroics has triggered an intense wave of research. Many materials have been checked for their dielectric permittivity or their polarization state. In this report, we call for caution when samples are simultaneously displaying an insulating behavior and a...
Resource Type:: Article

Magnetodielectric Effects from Spin Fluctuations in Isostructural Ferromagnetic and Antiferromagnetic Systems

Creator:: Lawes, G., Ramirez, A. P., Varma, C. M., and Subramanian, M. A.
Abstract:: We report on the effects of spin fluctuations, magnetic ordering, and external magnetic field on the dielectric constant of the ferromagnet SeCuO₃, and the antiferromagnet TeCuO₃. A model based on the coupling between uniform polarization and the q-dependent spin-spin correlation function is presented to explain the different behaviors for these...
Resource Type:: Article

Effect of oxygen concentration on the structural and magnetic properties of LaRh₁/₂Mn₁/₂O₃ thin films

Creator:: Sheets, W. C., Smith, A. E., Subramanian, M. A., and Prellier, W.
Abstract:: Epitaxial LaRh₁/₂Mn₁/₂O₃ thin films have been grown on (001)-oriented LaAlO₃ and SrTiO₃ substrates using pulsed laser deposition. The optimized thin film samples are semiconducting and ferromagnetic with a Curie temperature close to 100 K, a coercive field of 1200 Oe, and a saturation magnetization of 1.7μB per formula unit. The...
Resource Type:: Article

Employing capillary electrophoresis as a separation method for pharmaceutical analysis

Creator:: Lessard, Laura L.
Abstract:: Capillary electrophoresis as a technique has many applications in a broad range of fields including forensics, environmental analysis, and biological analysis and as a separation method for samples such as oligonucleotides, peptides, proteins, and pharmaceuticals. The research conducted herein is for the antibiotic pharmaceutical ciprofloxacin HCl and three impurities. Sample...
Resource Type:: Masters Thesis

The analysis of haloethylenes using Resonance Electron Capture - Mass Spectrometry and data analysis software

Creator:: Figard, Benjamin J.
Abstract:: Resonance Electron Capture Mass Spectrometry (REC-MS) is a sensitive experimental technique for the study of gas-phase compounds with positive electron affinity. This technique was used to study a class of compounds known as baloetbylenes containing chlorine and bromine substitutions. Haloetbylenes are an important class of compounds because ethylene is the...
Resource Type:: Masters Thesis

Fluorinated and deuterated surrogates for quantifying microbial transformation of chlorinated ethenes and ethanes in anaerobic groundwater

Creator:: Ennis, Elliot G.
Abstract:: Chlorinated aliphatic hydrocarbons (CAHs) such as vinyl chloride (VC) and 1,-2 dichioroethane (DCA), are wide-spread groundwater pollutants found at many contaminated field sites around the world. Quantitative tools are needed to determine the in situ rates of VC and DCA transformation to ethene in contaminated groundwater. The objective of this...
Resource Type:: Masters Thesis

Analysis of semi-volatile organic compounds in high elevation lake sediments

Creator:: Wang, Yunzhu
Abstract:: The transport and deposition of airborne contaminants, including semivolatile organic compounds (SOCs), to high elevation ecosystems is recognized as a potential threat to these ecosystems. The objectives of this research were to develop an analytical method to measure a wide range of SOCs in high elevation lake sediment and to...
Resource Type:: Masters Thesis

Development of materials and devices for separation of polyamido[a]mine dendrimers

Creator:: Tennico, Yolanda H.
Abstract:: Over the last decade, the use of highly branched macromolecules, called dendrimers, is emerging. Polyamidoamine (PAMAM) dendrimers, in particular, have attracted high interest due to their unique properties, such as well-defined size, shape, and solubility in water. Our group, as part of an interdisciplinary team, is currently working on developing...
Resource Type:: Masters Thesis

Synthetic studies on indolic enamide natural products: 1. Total syntheses of coscinamide A, concinamide B and igzamide: 2. Synthetic studies towards the synthesis of halocyamine B

Creator:: Ma, Yuelong
Abstract:: The 3-substituded indolic enamide moiety has been found in many marine compounds over the past 20 years. These indolic enamides exhibit various biological properties such as cytotoxic, anthelmintic, antimicrobial and HW-inhibitory activities. Among these indolic enamides, some are (E)-enamides, like coscinamide A and coscinamide B, others are (Z)-configuration in their...
Resource Type:: Masters Thesis

Measuring in situ biotransformation in BTEX-contaminated groundwater

Creator:: Alumbaugh, Robert E.
Abstract:: Benzylsuccinate (BSA), methylbenzylsuccinate (methylBSA), and ethylbenzylsuccinate (ethylBSA) are unambiguous anaerobic biotransformation products from toluene, xylenes, and ethylbenzene decay, respectively, and may be used to indicate intrinsic bioremediation is occurring at hydrocarbon-contaminated sites. In order to improve upon current methods that detect and quantify anaerobic hydrocarbon metabolites in field samples, solid-phase-extraction...
Resource Type:: Masters Thesis

Synthesis, structure and properties of some transition metal oxides

Creator:: Li, Jun
Abstract:: See pdf
Resource Type:: Dissertation

Synthetic studies toward the total synthesis of amphidinolide B₁

Creator:: Zhang, Wei
Abstract:: Amphidinolide B₁ is one of the most potent cytotoxic compounds in the amphidinolide family. Its bioactivity and intriguing structure has drawn attention from synthetic chemists. Although numerous synthetic efforts toward the total synthesis of amphidinolide B₁ have been published, it still remains an unconquered synthetic target. One of the unique...
Resource Type:: Dissertation

Transparent p-type conducting BaCu₂S₂ films

Creator:: Park, Sangmoon, Keszler, Douglas A., Valencia, Melinda M., Hoffman, Randy L., Bender, Jeffrey P., and Wager, John F.
Abstract:: p-type conducting films of α- BaCu₂S₂ have been deposited onto glass and KBr substrates, yielding a conductivity of 17 S/cm and a Hall mobility of 3.5 cm²/Vs. For a 430-nm-thick film, the optical transparency approaches 90% in the visible portion of the spectrum at 650 nm, and a transparency of...
Resource Type:: Article

Development of organocatalyzed, intramolecular heteroatom Michael addition and application towards alkaloid synthesis

Creator:: Carlson, Erik
Abstract:: Effective methods for the enantiopure formation of substituted piperidine rings are significantly important due to their presence in alkaloid products. A valuable method to form these ring systems would be via an intramolecular heteroatom Michael addition from the corresponding enone or enal. Described herein is a methodolgy that has been...
Resource Type:: Masters Thesis

Mass spectrometry-based identification and characterization of protein and peptide adducts of lipoxidation-derived aldehydes

Creator:: Chavez, Juan D.
Abstract:: Oxidative stress is recognized as an important underlying factor in the pathogenesis of many degenerative diseases as well as normal senescence. The free radicals, reactive oxygen species (ROS) and electrophiles produced during oxidative stress are capable of modifying nucleic acids, lipids and proteins. There are a variety of oxidative modifications...
Resource Type:: Dissertation

Tandem mass spectrometric analysis of protein and peptide adducts of lipid peroxidation-derived aldehydes

Creator:: Wu, Jianyong
Abstract:: The adduction of proteins and other biomolecules by electrophilic lipid peroxidation products such as 4-hydroxy-2-nonenal (HNE), 4-oxo-2-nonenal (ONE), malondialdehyde (MDA) or acrolein (ACR) is thought to be an initiating and/or propagating factor in the pathophysiology of several diseases such as atherosclerosis, diabetes, Alzheimer's, Parkinson's and other age-related disorders. The identification...
Resource Type:: Dissertation

Applications of high resolution Coherent Anti-Stokes Raman scattering spectroscopy

Creator:: Chrysostom, Engelene t. H.
Resource Type:: Dissertation

Studies towards the total syntheses of (+)-phomactins A, D and G

Creator:: Schwartz, Keith D.
Abstract:: Studies towards the total synthesis of (+)-Phomactin A (1), D (6), and G (9), fungal metabolites with unique molecular architecture and pronounced biological activity, are described. These studies resulted in the synthesis of advanced intermediates 354 and 356, which contain all of the carbon atoms of 1, 6 and 9....
Resource Type:: Dissertation

The transient electric birefringence of nanomaterials: alignment mechanism, characterization, and its application towards aligned polymer nanocomposites

Creator:: Teters, Chad N.
Abstract:: The experimental and theoretical bases of transient electric birefringence (TEB) and its application in a variety of nanomaterials, including Na-montmorillonite, cellulose nanocrystals (CNXL), and CdSe quantum dots (QDs) will be presented. TEB is a phenomenon attributed to the alignment of particles in response to an applied electric field and has...
Resource Type:: Dissertation

Part I: Synthetic studies toward the southern portion of Azaspiracid-1; Part II: Total synthesis of amphidinolide B₁ and the proposed structure of amphidinolide B₂

Creator:: Lu, Liang
Abstract:: The structural architecture present in marine toxin azaspiracid - 20 stereocenters, 9 rings, 3 separated spirocenters - has attracted considerable synthetic attention. Our efforts toward the synthesis of azaspiracid have led to the completion of both C₁-C₂₆ northern and C₂₇-C₄₀ southern halves. Herein, the synthesis of southern FGHI ring system...
Resource Type:: Dissertation

Micro total analysis system for in-situ and autonomous spectrophotometric monitoring of iron in groundwater

Creator:: Koch, Corey R.
Abstract:: We have developed a compact micro total analysis system (μTAS) to serve as a platform for in-situ spectrophotometric water quality monitoring. Individual fluidic, optical, and electrical components were designed, developed, and characterized. These components were combined in both an integrated (single lithographic “chip-based” platform) and a modular manner. The microfluidic...
Resource Type:: Dissertation

Expanding the scope of a Diels-Alder approach to biaryl synthesis

Creator:: Schwartz, Johanna Perkins
Abstract:: A Diels-Alder approach to biaryls (DAB) has been applied towards the synthesis of highly substituted, programmable biaryl templates. Tri- and tetra-ortho-substituted biaryls can be produced in just three to four steps from commercially available materials utilizing the Diels-Alder [4+2] cycloaddition. The methods described herein will illustrate the ability of mono...
Resource Type:: Dissertation

Determination of ethyl glucuronide and ethyl sulfate as human biomarkers of alcohol exposure in urine by liquid chromatography/electrospray tandem mass spectrometry with large volume injection

Creator:: Hu, Yan
Abstract:: This research was undertaken to develop a sensitive, selective, and rapid analytical method to measure ethyl glucuronide (EtG) and ethyl sulfate (EtS) in urine as urinary biomarkers of alcohol exposure. Large-volume injection (LVI) coupled with liquid chromatography / electrospray tandem mass spectrometry was used to eliminate the need for either...
Resource Type:: Masters Thesis

Polyion sensors based on induced ion extraction

Creator:: Fordyce, Katherine
Abstract:: A novel method for detecting the peptidase activity of clinically relevant peptidases was investigated using solid-contact electrochemical polyion sensors under chronopotentiometric control. Complete instrumental control over ion-extraction was accomplished by incorporating a lipophilic electrolyte into the ion-selective membrane; the sensors had no intrinsic ion-exchange capabilities. The sensors were used to...
Resource Type:: Masters Thesis

Galvanostatic control of ion selective electrodes with the solvent polymeric membrane

Creator:: Perera, Hasini R.
Abstract:: Detection technique that proposed utilizing electrochemically controlled, reversible ion extraction into polymeric membrane in an alternating galvanostatic/ potentiostatic mode was introduced. This method is studied in detail to comprehend the advantages of the novel sensor (pulstrode) compared to the potentiometric ion selective electrode (ISE), studies included possible applications and limitations....
Resource Type:: Dissertation

Total synthesis of sparteine alkaloids from a common tetraoxobispidine intermediate

Creator:: Melbardis, John
Abstract:: In previous work (Blakemore et al. Org. Lett. 2005, 7, 4721; Heterocycles 2006, 70, 609), successful elaborations of the lupine alkaloids (±)-α-isosparteine (dl-2) and (±)-β-isosparteine (dl-3) were realized from a common tetraoxobispidine precursor, 3,7-diallyl -2,4,6,8-tetraoxo-3,7-diazabicyclo[3.3.1]nonane (93). Herein, the tetraoxobispidine approach to lupine alkaloids was extended to a total synthesis of...
Resource Type:: Masters Thesis

Fabrication and application of polymer based microfluidic devices

Creator:: Koesdjojo, Myra T.
Abstract:: The concept of reducing laboratory operations in scale such that they fit on a microfluidic chip has been met with great enthusiasm. Lab-on-a-chip devices promise to be cost effective to operate due to reduced reagent consumption, have the potential to offer shorter analysis times due to their short path lengths,...
Resource Type:: Dissertation

Catalytic desymmetrization of D₂d̳-symmertic proprochiral tetrasubstituted biphenyl compounds: a novel approach to the synthesis of axially chiral C₂-symmetric molecules

Creator:: Gunderson, Jeremey Tyson
Abstract:: Many D2d-symmetric 2,2',6,6'-tetrasubstituted biphenyls are readily prepared via net oxidative dimerization of appropriate 1,3-disubstituted benzenes. Conversion of such proprochiral compounds to useful C2-symmetric chiral biphenyls requires formal replacement of two substituents on opposing aryl ring units with alternate groups. This under exploited desymmetrization tactic has been demonstrated for the generation...
Resource Type:: Masters Thesis

Growth and characterization of wide–gap semiconducting oxide and chalcogenide thin films by pulsed laser deposition

Creator:: Newhouse, Paul F.
Abstract:: The preparation and characterization of thin film oxides and chalcogenides by pulsed laser deposition (PLD) is presented. An overview of fundamental PLD concepts are presented and are followed by a description implementation and development of the PLD systems at OSU. We present the results of thin film growth of high...
Resource Type:: Dissertation

Direct patterning of solution deposited metal oxides

Creator:: Stowers, Jason K.
Abstract:: Patterning of metal oxides typically involves a multi step process, involving depositing a resist, patterning that resist with some form of lithography, etching the oxide through the resist, and finally removing. This process can be simplified if the resist is removed and replaced with a metal oxide that can be...
Resource Type:: Dissertation

Semi-volatile organic compounds as molecular markers for atmospheric and ecosystem transport

Creator:: Genualdi, Susan A.
Abstract:: The use of semi-volatile organic compounds (SOCs) as molecular markers to identify the contributions of regional and long-range atmospheric transport, as well as current and historic sources, and contaminant deposition in remote ecosystems of the Western U.S. was investigated. Trans-Pacific air masses influenced by Siberian biomass burning events had elevated...
Resource Type:: Dissertation

Aqueous chemistries for oxide electronics

Creator:: Meyers, Stephen T.
Abstract:: The variegated aqueous chemistries of metal cations are applied to the design and synthesis of non-toxic solution precursors suitable for additive printing of large-area oxide electronics. Polycondensation behaviors of aqueous Al+3 and PO4 +3 are manipulated in the deposition of atomically smooth amorphous aluminum oxide phosphate (AlPO) dielectric films. AlPO...
Resource Type:: Dissertation

Large volume (1,800 µL) injection HPLC/MS/MS for the quantitative determination of illicit drugs and human urinary biomarkers in municipal wastewater

Creator:: Chiaia Hernandez, Aurea C.
Abstract:: A sensitive, selective, rapid analytical method based on large-volume injection (LVI) liquid chromatography/ tandem mass spectrometry was developed using commercially-available hardware that eliminates the need for either off-line or on-line solid phase extraction. Centrifugation followed by the direct injection of 1,800 µL was used for the quantification of illicit drugs,...
Resource Type:: Masters Thesis

Broadening the scope of the modified-Julia reaction : a mild and stereoselective method for the synthesis of (Z)-configurated α,β-unsaturated lactones

Creator:: Giesbrecht, Heath Eugene
Abstract:: An intramolecular variant of the modified-Julia olefination was demonstrated by the synthesis of α,β-unsaturated lactones in a mild and (Z)-selective fashion. The lynchpin reagent (benzothiazol-2-sulfonyl) acetic acid was synthesized in a straightforward fashion in 86% overall yield from commercially available 2-mercaptobenzothiazole via conversion to ethyl (benzothiazol-2-ylthio)acetate by base mediated alkylation...
Resource Type:: Masters Thesis

Atropisomeric 8,8'-biquinolyl derivatives : synthesis, properties and applications

Creator:: Milicevic, Selena D.
Abstract:: 7,7'-Dihydroxy-8,8'-biquinolyl (azaBINOL) was prepared from 7-hydroxyquinoline via N,N-dimethyl O-quinol-7-yl carbamate by directed ortho-metallation followed by FeCl₃-mediated oxidative coupling of the 8-lithioquinoline intermediate. Saponification of the resulting dicarbamate provided crystalline (±)-azaBINOL in 56% overall yield. 6,6'-Bis(dimethylaminocarbonyl)-7,7'-dihydroxy-8,8´-biquinolyl was prepared from the same dicarbamate by a double anionic-Fries rearrangement in 43% yield. 7,7'-Bis(diethylamino-carbonyloxy)-6,6'-diiodo-8,8´-biquinolyl...
Resource Type:: Dissertation

Synthesis of novel ambifunctional atropisomeric 2,2',6,6'-tetrasubstituted biphenyls and investigation of their properties and organocatalytic activity

Creator:: Sephton, Mark Alan
Abstract:: Ambifunctional axially chiral 2,2',6,6'-tetrasubstituted biphenyls containing nucleophilic (or basic) functional groups juxtaposed with hydrogen-bond donors were synthesized and their properties studied. Applications for the prepared biaryls as potential organocatalysts for enantioselective carbon-carbon bond forming reactions were examined. Processes investigated included: aldol, Michael, nitroaldol (Henry), and Baylis-Hillman reactions. The novel amidoamine...
Resource Type:: Dissertation

Synthesis and structural determination of alkali and alkaline earth metal containing bismuth vanadates

Creator:: Bliesner, Rebecca J.
Abstract:: Exploratory synthesis plays an important role in the quest to discover new materials. There are very few structurally characterized alkali metal containing bismuth vanadates. Hybridization of the 6s and 6p orbitals of Bi[superscript 3+] and the resulting lone electron pair yields some very interesting stereochemistry and steric related properties. Some...
Resource Type:: Dissertation

A Diels-Alder approach to biaryl synthesis

Creator:: Ashburn, Bradley O.
Abstract:: An expedient approach to the synthesis of a wide range of highly programmable biaryl templates has been accomplished. Utilizing the Diels-Alder [4+2] cycloaddition, a wide range of tri- and tetra-ortho-substituted biaryls have been synthesized in only three to four steps from commercially available materials. We have successfully synthesized entire classes...
Resource Type:: Dissertation

Synthesis and characterization of novel stationary phases for small scale liquid chromatographic separations of proteins and nanoparticles

Creator:: Hutanu, Daniela
Abstract:: The emerging field of nanotechnology strictly requires the micro-scaling of the available separation technology and the design of novel devices for separations of molecules of interest. The separation of proteins and nanoparticles is challenging due to their relatively large size, non-specific adherence to surfaces and instability in many solvents. This...
Resource Type:: Dissertation

Luminescent sulfides and solution-deposited oxide thin films

Creator:: Anderson, Jeremy T.
Abstract:: Solid state luminescent sulfides are prepared as powders in order to elucidate the relationship between structure and light emission. While the sulfides studied in this dissertation are known phosphors, materials are investigated in a variety of new ways. Elementary properties and structures of MgS are reviewed, and preparation of MgS...
Resource Type:: Dissertation

Design, characterization, and application of spectrometers for determination of low-level dissolved oxygen with small-volume sampling methodology

Creator:: Cakin, Defne
Abstract:: New analytical methods and instrumentation were developed for the determination of dissolved oxygen (DO) at low concentrations in water. The methods were based on monitoring the absorbance increase due to the oxidation of reduced indigo carmine (IC) by oxygen in the sample in different types of spectrometer cells. Spectrophotometer cells...
Resource Type:: Dissertation

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