The goal of this work was to investigate the properties of existing atomic emission systems which are useful for element-selective detection of chromatographic effluent. A microwave induced plasma (MIP) system has been optimized for the selective detection of boron in the effluent of a gas chromatograph. A method was developed for the analysis of total boron present in several lubrication oil additives and in several formulated lubrication oils. Values obtained by this method compare favorably with those obtained by other atomic emission spectroscopic (AES) methods. A direct current plasma (DCP) system has been optimized for the selective detection of boron in flowing organic liquid streams. A method was developed for the analysis of total boron present in several lubrication oil additives by flow injection analysis (FIA). A method was also developed for the qualitative separation "speciation" of these additives by size exclusion chromatography-DCP. Values obtained through this method compare favorably with values obtained through other AES methods. The MIP system was optimized for the selective detection of titanium in the effluent of the gas chromatograph. This system was used to analyze a group of reaction mixtures containing novel titanium chelates and organo-metallic compounds, as well as several organo-titanium-boron compounds. The MIP system was optimized for the selective detection of several of the group VA and group VIA elements in the effluent of the gas chromatograph. This system was used to characterize a series of coal standards (the Argonne Premium Coal Standards) by pyrolysis-GC-AES. Volatile compounds containing nitrogen, oxygen and sulfur were detected. The Py-GC-AES method was used to characterize several other coal, sedimentary and kerogen samples. Volatile phosphorous, arsenic, and selenium compounds were detected, as were compounds of nitrogen, oxygen and sulfur. The MIP system was evaluated as a detector suitable for on-line elemental analysis by simultaneous multi-element detection. Several anomalies were observed in the detector response to hydrogen, non-linear response being observed within a large set of model compounds examined. Chlorinated molecules demonstrated enhanced hydrogen response. The anomalies do not greatly affect the empirical formulae calculated for compounds, provided that the analyte mass delivered to the plasma is above $1\times10\sp{-10}$ g. Empirical formulae for a variety of model compounds, as well as for a mixture of sixteen chlorinated pesticides are presented. (Abstract shortened by UMI.)

Separation of basic compounds with maintenance of adequate peak shape has been among the most taxing of HPLC applications. Also, complete chemical class fractionation of various fuel oils has been difficult with the methods currently in use. A novel stationary phase based on newly developed surface bonding organophosphate chemistry was developed to address both of these HPLC problems using relatively simple operational procedures. The stationary phase was synthesized, characterized, and packed into a 4.6 x 250 mm HPLC column prior to conducting the HPLC investigations. Studies to investigate the peak shape of basic compounds, the separation of individual basic compounds, class fractionation using model fuel oil compounds, and class fractionation of actual fuel oil samples were conducted. The stationary phase produced chromatographic peaks of basic compounds which demonstrated minimal tailing. Chromatographic separations of various basic compounds were performed to demonstrate the increased resolution possible with a column exhibiting these characteristics. The class fractionation of fuel oils was demonstrated first using model compounds followed by the fractionation of actual fuel oil samples. Recovery studies were also performed for the fuel oil fractionation. The novel stationary phase produced exhibited characteristics which are desirable for the stated applications. Minimal tailing was produced without the use of buffers or the degradation of the column while performing chromatographic separations of basic compounds. A four class fractionation of fuel oil was produced using a linear binary gradient. Both of these results are significant advances in addressing the two stated chromatographic problems.

Many elemental analysis techniques can accurately produce and process a large volume of data in a relatively short time. However, many techniques require that the sample be in the form of a solution. The preparation to meet this requirement often involves a significant degree of time and knowledge from a chemist. Sample preparation automation can be developed to eliminate or reduce these time and knowledge requirements. A flow-through digestion device and an expert system were developed as part of an automation approach for sample preparation prior to inductively coupled plasma atomic emission spectometry (ICP-AES) analysis. The flow-through device was developed for on-line stopped-flow microwave heated digestions of organic biological material. Milk, whole blood, and urine were digested with concentrated nitric acid, concentrated sulfuric acid, and 30% hydrogen peroxide. Digestion of a sample occurs within the device when the sample and reagents are exposed to microwave energy from a commercial apparatus. The physical and chemical characteristics of the digestions dictated the device design. The expert system was designed to perform open-vessel sample digestion method development. After an initial sample digestion was attempted, and the expert system used its modification rules to develop a successful digestion procedure. The expert system then accessed a simplex program to optimize key parameters. The expert system was capable of developing accurate digestion procedures for whole milk, whole blood, and urine. Accurate results were obtained from the analysis, minimal analyte loss and contamination occurred.

Development of sensitive methods for chemical analysis requires comprehensive understanding of the various experimental contributions to signal, interferences, and noise. This premise was applied to the development of multiphoton photoionization spectroscopy and optical polarimetry. For the former, two methods were attempted to improve performance in polar solutions. Auto-by-cross correlation was implemented as a signal processing scheme for quantifying transient signals, which included photoionization. Careful analysis of background fluctuations and signal-to-noise ratio behavior showed that, while the method itself was useful, certain peculiarities of its implementation with photoionization prevented full realization of the experimental goals. The second innovation for photoionization was to replace most of the polar solvent with nonpolar solvent, and sequester the polar solvent and analyte in the interior of a reverse micelle. Analysis of the background noise showed that noise reduction was excellent; solvent noise was reduced nearly to the level of heptane. The photoionization signal also decreased, such that no gain in signal-to-noise ratio was realized. However, it was shown that the microemulsion solutions offered a much better environment for analysis of aqueous-soluble compounds. It was also shown that microemulsions provided a means of performing analyses by photoionization that were otherwise impossible, such as at nonneutral pH. Numerical simulations were employed extensively in the development and evaluation of a laser-based optical polarimeter. Numerous simulations showed the optimum operating conditions for a Faraday rotator-based polarimeter, and provided an accurate means of evaluating previously published predictions. An experimental polarimeter was also constructed, and the source noise was manipulated to correspond with that of the simulations. It was shown that, when all experimental variables were taken into account, the simulations yielded very accurate predictions of polarimeter behavior.

Flow analysis procedures have used a wide variety of detectors. Magnetic susceptibility and graphite furnace atomic absorption spectrometry are two detection techniques with limited applicability to flow procedures. Most magnetic susceptibility balances are not applicable to flowing streams. The use of GFAAS has been limited due to the presence of several timing problems. The Johnson Matthey magnetic susceptibility balance is readily adaptable to flowing streams. Analytical parameters such as detection limits and sensitivity were determined for several ferromagnetic and paramagnetic species. Retention of the metal cations on a column of ion exchange resin situated within the poles of the magnets allowed preconcentration of the cations. The passage of a stream of borohydride through the column containing the immobilized cations caused a dramatic increase in signal. A simple method for calibrating the temperatures of the drying stage of the GFAAS program based on the visual observation of the melting of a number of compounds is presented. Recirculating loop technology was used to devise an interface between a flow injection manifold and a GFAAS system. The use of a recirculating loop eliminates the timing problems common to FIA-GFAAS. A number of Pb solutions of known concentration were analyzed and accurate results obtained. Preconcentration of Pb on C-18 columns and various ion exchange resins was performed before introduction into the recirculating loop. Once the system had been shown to yield accurate results, wine samples were analyzed. The determination of Pb in wines is difficult due to the low concentration of Pb in wines and the complex matrix. Flow analysis procedures were used to isolate the Pb from the matrix before analysis by GFAAS.

The goal of this research has been to enhance sample decomposition techniques through the coupling of flow technology with current sample digestion methodology in order to approach the characteristics of an ideal digestion system--one which is rapid, minimizes sample and reagent consumption, avoids analyte loss or contamination, rapidly transfers the resulting digest into the detector for measurement, and is amenable to automation. A stopped-flow, high pressure manifold incorporating a resistively heated thermal oven was developed for the on-line dissolution of slurried samples having a predominantly organic matrix. The manifold, which was directly coupled with a flame atomic absorption spectrometer, was determined to be most applicable to samples in which the analytes were loosely bound to the bulk material. This was a consequence of the limited oxidation potential of the system resulting from insufficient headspace volume for the expansion of nitrous oxides which are believed to be crucial intermediates in the digestion process, and rapid overpressurization of the manifold due to a lack of control over the rate of energy input to the system. A stopped-flow, high pressure manifold incorporating a microwave oven was subsequently developed to overcome the limitations of the thermal oven manifold. A microwave heated glass reaction column provided ample headspace for the expansion of gaseous reaction products and the use of power programming allowed for control of the energy flux introduced to the system. A dual stage manifold depressurization system was designed and interfaced via an autosampler to both a flame atomic absorption and an inductively coupled plasma atomic emission spectrometer for the determination of trace elements in solid samples. A study of the manifold operating parameters, such as flow rate, carrier stream composition, residence time, energy input, and gas-liquid separation was conducted in this work. Slurry sample preparation and handling and instrumental response to samples in concentrated acid matrices were also investigated.

Atmospheric chemistry has primarily focused on outdoor environments for many decades. Plenty of models based on the findings of outdoor atmospheric researchers have been built to deepen the understanding of outdoor environments and predict how certain changes in specific parameters may affect the overall atmosphere. The same cannot be said for indoor environments, which remain relatively unknown despite the fact that humans in developed countries spend the vast majority of their lives in indoor environments. This thesis seeks to provide an early look at the makeup of indoor surface films, specifically at their molecular compositions and thicknesses. These characteristics are important for understanding how surface films, a major route of human exposure to compounds which can negatively affect health, begin to form and how they evolve over time with exposure to other indoor species. Two types of surface films were analyzed in this thesis: lab-created surface films of commercial household cleaners sprayed onto glass plates, and “real-world” surface films extracted from areas of a high-traffic lecture hall on a college campus. Samples were extracted with an Indoor Surface Extractor (ISE) and analyzed with quadrupole ion trap mass spectrometry (MS), Orbitrap MS, and/or Fourier-transform ion cyclotron resonance MS. Resulting mass spectra were used to identify individual components observed in the surface films. Both listed ingredients in the household cleaners and compounds not listed as ingredients were observed in their surface film extracts’ mass spectra; quaternary amine compounds (QACs) were observed in many of the real-world surface film extract mass spectra, likely present from increasing COVID-19 sanitary measures. In a second part of this thesis, quantification of organic material in surface films was executed with aerosol MS. Citric acid was used as a proxy for the organic surface film matrix in order to build calibration curves for the response of organic material relative to two different internal standards. These calibrations were then applied to some of the same surface film extracts analyzed by qualitative MS methods to estimate the thicknesses of the films that were extracted; the results fell in line with previously published estimates of indoor surface film thickness, indicating that the experimental parameters being used are in the correct general range and can be fine-tuned for future quantification studies.

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