Index Catalog // ScholarsArchive@OSU

Studies of ammonia gas transport and fluorimetric detection in an aqueous solution

Creator:: Clark, Eric J.
Resource Type:: Masters Thesis
Full Text:: progressed. Instrumentation Fluorimetric monitoring of the OPA/NH3 reaction was performed with a modified

Comparison between lichen, conifer needles, resin-based passive air sampling devices (PASDs), and snow to monitor semi-volatile organic compounds (SOCs) in the atmosphere

Creator:: Schrlau, Jill E.
Abstract:: The purpose of this research was to compare four different media that were used to monitor SOC atmospheric concentrations in remote ecosystems. The accumulation of semi-volatile organic compounds, including pesticides, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), was investigated in lichen, 2-year old conifer needles, resin-based passive air sampling...
Resource Type:: Masters Thesis
Full Text:: sampling system for monitoring persistent organic pollutants in the atmosphere. Environmental Science

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

Applications of redox indicators for evaluating redox conditions in environmental samples

Creator:: Jones, Brian Dion
Resource Type:: Dissertation
Full Text:: ) of interest. This method also requires sampling of the system and extensive laboratory analysis. In

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
Full Text:: sampling, environmental monitoring, and disposable applications. This device incorporates a LED light

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
Full Text:: of Low-Level Dissolved Oxygen with Small-Volume Sampling Methodology Abstract approved

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
Full Text:: Evaluation of sampling/preconcentration techniques and

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
Full Text:: allow higher frequency monitoring, and results can be less biased due to sampling, storage, or

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
Full Text:: degree of Doctor of Philosophy in Chemistry presented on May 1, 2006. Title: Monitoring Redox

Adapting the Methylene Blue Sulfide Detection Method for Use in a Microfluidic in-situ Monitoring Device

Creator:: Monares, Shane W.
Abstract:: Sulfide is an important species to measure in environmental water samples. The spectrophotometric detection method for reduced sulfur species (sulfide) based on generation of methylene blue was adapted to work in an apparatus utilizing microfluidic PDMS mixing and observation cells with flow channels in the 100 μm range. The benefits...
Resource Type:: Honors College Thesis
Full Text:: for Use in a Microfluidic in-situ Monitoring Device. Abstract approved

Development of Miniature Wire pH Sensors for Real-Time Monitoring of the Streptococcus Mutans Biofilm

Creator:: Wong, Derek C.
Abstract:: The interface between a biofilm and the underlying substrate to which it is attached is challenging to study. Currently, available methods of studying this microenvironment have not been able to record data in real-time over a time period in the range of days. To address this challenge, we report the...
Resource Type:: Honors College Thesis
Full Text:: Real-Time Monitoring of the Streptococcus Mutans Biofilm by Derek Wong

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
Full Text:: continuous monitoring in a flow stream. Sample sob Magnetic N2 outlet gas agent ne sampling device

Method validation of quantitative analysis of oxylipins in human plasma via mass spectrometry

Creator:: Bloom, Madeline B.
Abstract:: Oxylipins are a class of bioactive lipid metabolites derived from polyunsaturated fatty acids (PUFAs) via enzymatic and non-enzymatic pathways. In order to elucidate their overall biological effects, the knowledge of the entire oxylipin profile is needed as oxylipins can have similar or opposing effects in regard to inflammatory events. Their...
Resource Type:: Honors College Thesis
Full Text:: concentrations in plasma and other tissues. A multiple reaction monitoring method (MRM) using liquid

Comprehensive, Low-Cost Wicking Microfluidic Analytical Devices for Clinical Diagnostics and Environmental Analysis

Creator:: Bandara, Gayan C.
Abstract:: Analytical techniques are utilized in a wide variety of applications. Traditionally, analytical measurements are achieved by trained personnel in a laboratory setting using expensive scientific instruments, which limits their applicability in resource-limited areas and point-of-care applications. Therefore, the concept of enabling these laboratory-based qualitative and quantitative assays in microfluidic device...
Resource Type:: Dissertation
Full Text:: environmental pollution monitoring were explored. In the first component of this dissertation, the

High-resolution X-ray photoelectron spectroscopy of CO₂ and other small molecules

Creator:: Hahne, Jeffrey A.
Abstract:: The carbon is photoelectron spectrum of CO₂ has been measured with very high photon energy resolution. The natural lifetime of the carbon is hole state has been determined from a series of spectra taken at photon energies of 308, 320, and 330 eV. The measured values of the lifetimes show...
Resource Type:: Masters Thesis
Full Text:: correctly the observed electron spectrum near threshold. The lifetime widths reported here are critically

Fundamental studies of a gas-jet enhanced sputtering system and its applications

Creator:: Kim, Hyo-jin
Abstract:: The use of gas jets in a sputtering cell makes this direct sampling method practical for atomic absorption and mass spectrometry determinations. With a commercial six-jet sputtering source, the Atomsource (Analyte Corp., Grants Pass, Oregon), that directly atomizes solid samples for conventional atomic absorption spectrophotometers, the sample loss rate for...
Resource Type:: Dissertation
Full Text:: use of gas jets in a sputtering cell makes this direct sampling method practical for atomic

Spectroscopic investigation of atomic and molecular species formed in a laser microprobe plasma using a wavelenth calibrated tunable dye laser

Creator:: Beenen, Gerhard Joseph
Abstract:: The temporal and spatial characteristics of a laser microprobe plume were investigated using the spectroscopic methods of emission, absorption and fluorescence. The plume was produced by rapid vaporization of a small quantity (1 μg) of a solid sample using a focussed pulsed dye laser (110 MW/cm²). For absorption and fluorescence...
Resource Type:: Dissertation
Full Text:: the sampling atmosphere controlled. Sample chamber pressures of 25 torr to 300 torr were used. The

Optimization by transfer function estimation of the galvanovoltammetric determination of dissolved chlorine in a flowing stream

Creator:: Miller, Clinton Earl
Abstract:: Optimization of the galvanovoltammetric determination of dissolved chlorine in a flowing stream was achieved through the use of an analog computational device and improvements in the design of the galvanovoltammetric cell and accompanying electronic circuitry. An analysis system, applicable to industrial use over a range of flow rates and dissolved...
Resource Type:: Masters Thesis
Full Text:: galvanovoltammetric cell and its associated sampling system. An analog computational device was built to rapidly

Per- and Polyfluoroalkyl Substances (PFAS) in Environmental Air-Water Matrices and Light Non-Aqueous Phase Liquids (LNAPL)

Creator:: Schwichtenberg, Trever J.
Abstract:: The presence of per- and polyfluoroalkyl substances (PFAS), organic contaminants first synthesized in the 1940s, has been reported worldwide in a variety of environmental matrices and ultimately in biological systems including humans. Ongoing research into PFAS has included identifying novel PFAS, assessing their fate and transport in the environment, and...
Resource Type:: Dissertation
Full Text:: . In Chapter 3, existing methods for sampling the surface microlayer (SML) were deployed on a PFAS

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
Full Text:: and the shift of ionization thresholds with increasing water content. Electronic Spectroscopy of

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