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He has worked widely on the analysis of petroleum (crude oil) and its refined products by using a wide variety of chromatographic and spectral techniques. These include gas chromatography with mass spectrometer detection, with element specific detection for sulfur, nitrogen, phosphorous, and metals; liquid chromatography (HPLC); fluorometry; FTIR, NMR, and UV spectroscopies. He has worked on numerous product and processing problems, particularly those involving olefins and polycyclic aromatic hydrocarbons.

He is an expert on gas and liquid chromatography, fluorescence, and UV instrumentation. He has used a variety of these and worked with instrument companies on better designs, better applications, and software improvements. He was a member of ASTM committee E-13, which deals with instrument testing and calibration for UV and fluorescence instruments.

He is a world-class expert on aromatic compounds, both hydrocarbons and those with sulfur or nitrogen. He is especially strong on those with two or more rings. He has published approximately 100 scientific research papers, several review articles or book chapters, one book, and has three patents on the polycyclic aromatic compounds. He was awarded the 2005 Erich Clar Award by the International Society on Polycyclic Aromatic Compounds for his research work on their chemistry, occurrence, and analysis.

He has used both classic wet chemical methods and instrumental chemical analysis for many problems. These include characterizing the nickel and vanadium compounds in petroleum; characterizing organic and inorganic phosphorous-based polymers; identifying hard to process nitrogen and sulfur compounds; and analyzing for molecular sulfur (S8) in materials. He has used unique combinations of equipment, such as an HPLC with an ICP detector to identify specific compounds.

He has worked from microbore scale to using columns that could separate kilogram quantities. The largest scales were used to isolate fractions where chemical and spectroscopic analyses were used to gather full characterization. He has also used nitrogen, sulfur, phosphorous, halogen, and metal specific detection in gas and liquid chromatography.

He built and assembled numerous instruments for unique solutions. These included a non-carbonb dioxide supercritical fluid extraction/ chromatography; an HPLC with ICP detection for iron, nickel, vanadium, and other elemental detection; a gas chromatograph with FTIR traps; and an automated extractor for separating C60 fullerene.

He worked on GC-MS environmental applications for PBCs, pesticides, and polycyclic aromatic hydrocarbons. This involved trying new GC phases (liquid crystal based, for example) and various chemical ionization techniques to tell isomers apart.

He has performed water and soil analyses for priority pollutants, persistent organic pollutants, and other compound types. Often these were customized analyses for US EPA reporting where the standard methods were insufficient in detection limit or where sample matrix effects made the analyses suspect. This work included various sample cleanup and fractionation schemes to remove interferences.

He is a world-class expert in fluorometry. He has written several research papers, reviews, and a book chapter on the use of fluorometry in environmental and other analyses. His research is often cited in articles on the behavior of fluorescent compounds and how to avoid interferences, quenching and other matrix effects, and other problems.

He was formally educated in GC-MS and have used it as a method for over two decades. This long experience has given him the ability to interpret electron-impact spectra and not have to rely on library searches. This helps when new chemical compounds are the target, or cause of a problem (such as in degradation products of a known compound). He is expert on both ends, so the GC is not just a sample introduction device for the MS nor is the MS just some fancy detector for the GC. This leads to a wider view of result where the question "Does the GC behavior reflect the MS result?" can be answered.

He has worked on hydrocarbon analyses from methane to waxy parrafins of over a hundred carbon atoms; from benzene to aromatics with over thirty rings. This involved a large number of techniques in sample preparation and analysis. The results were used in oil exploration (terpenes, steranes, hopanes, porphyrins); environmental issues (BTEX, polycyclics); petroleum processing and product issues (olefins, aromatics, saturates, etc.).

He worked using classic wet chemical tests, UV, FTIR, NMR, and other methods to determine compound types. He is strongly versed in mass spectral interpretation using ion-losses to determine functional types.

To characterize materials, especially mixtures, to answer "What is that stuff?" has often popped up. This includes the related question of "What happened to this stuff?" when a known material degrades. Separations, chemistry, and spectroscopy provide pieces to these jigsaw-puzzle type of problems. The need is not "How much?", but "What?".

When "How much?" needs to be answered, many issues arise. These involve reliability in measuring amounts. Sample preparation through extraction or fractionation; removal of interferences chemically or instrumentally; and improving detection limits and linearity are some of the tasks in answering reliably. He has worked on these problems for both EPA reporting and FDA registration/ application.

Reviewed data on soil and water contamination at a power plant site; testified on its suitability and interpretation.Assessed separation and purification for a novel group of material for use as nanotechnology platforms.Developed in-plant monitoring methods for process contaminants and recommended remediation approaches.Worked on an application for FDA approval for a new component for cosmetics use; developed supporting chemical analyses for the application's data.Developed a trace-level oil spill method for the waters around oil drill platforms.