31 research outputs found
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A study of the source materials, depositional environments, mechanisms of generation and migration of oils in the Anadarko and Cherokee Basins, Oklahoma. Quarterly technical progress report, September 15, 1989--September 14, 1990
The geochemical characterization of petroleum and source rocks from the Anadarko Basin, Oklahoma, has continued. Major emphasis has seen on geochemistry of the Woodford shale
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Organosulphur compounds in coals as determined by reaction with Raney nickel and microscale pyrolysis techniques. Fifth quarterly report, October 1, 1995--December 31, 1995
This project is designed to study the nature of sulphur-containing organic compounds and their respective linkages in coals and related materials using a variety of microscale pyrolysis techniques combined with gas chromatography--mass spectrometry. The majority of the work will be undertaken using a PYRAN pyrolysis system purchased with funds from the DOE University Instrumentation Program. Since the last report, we have reached the point in the project that we are satisfied with the nickel boride chemical degradation method, and are now working our way through the large amounts of data collected by gas chromatography-mass spectrometry analysis. While we have tentatively identified a variety of compounds produced by the chemical degradation method with spectra from the literature, we have yet to confirm many of these identifications with pure standards or specialized oil samples. As a result we will present in this report chromatograms of one of the coals (Illinois No. 6) and compare the free aliphatic hydrocarbons with those compounds cleaved from the polar extract, asphaltenes and pre-extracted coal matrix
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A study of the source materials, depositional environments, mechanisms of generation and migration of oils in the Anadarko, Oklahoma. Progress report, September 15, 1990--September 14, 1991
This report is for the final year of a three-year funded project. A new proposal has been submitted and it is hoped that funding will continue for another three years. It is felt that good progress is being made with our work on studying the oils and source rocks in the Anadarko Basin. Furthermore a number of associated projects have evolved during this period which have also produced many useful results and various analytical methods have been developed. In Appendix I lists of students totally or partially supported by this work plus various publications are given. It is hoped that these will testify to our productivity arising from the DOE support over the past few years
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ISOPRENOID HYDROCARBONS PRODUCED BY THERMAL ALTERATION OF NOSTOC MUSCORUM AND RHODOPSEUDOMONAS SPHEROIDES
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A CHEMICAL DEGRADATION STUDY OF SOME BLUE-GREEN ALGAE and BACTERIA and ITS IMPLICATION ON THE ORIGIN OF THE ORGANIC MATTER IN KEROGEN
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ISOPRENOID HYDROCARBONS PRODUCED BY THERMAL ALTERATION OF NOSTOC MUSCORUM AND RHODOPSEUDOMONAS SPHEROIDES
An overview of environmental forensics
Environmental forensics has emerged as an important area of environmental studies over the past two decades. There are two basic aspects to any environmental investigation. The first being a conventional approach where the standard EPA (Environmental Protection Agency) methods are used to determine concentrations of selected compounds released into the environment. These methods are extremely well documented and widely used, but only provide information on specific target compounds. Whilst this information may be useful for monitoring purposes it is of little use when trying to determine the source of a spill or contaminants in the environment. If the purpose of an investigation is to determine the source of a contaminant, or point of release, then it is necessary to use a wide variety of analytical techniques and integrate all of the resulting data into one comprehensive data set. It may not always be possible to obtain a unique answer, particularly in the case of groundwater contaminants where there might only be one compound, for example MTBE or PCE. In that case if there are multiple possible sources in the area it may be difficult to narrow it down to a specific source. Furthermore fingerprinting tools that may be useful with complex mixtures may not be directly applicable to single component mixtures. The purpose of this paper will be to provide a brief overview, along with some recent examples of the type of information that is typically obtained in an environmental forensic investigation and how this information may be interpreted. It should be noted that all these examples are related to organic contaminants in the environment since that is the major area of focus at this time. Examples will involve hydrocarbons, chlorinated solvents, and MTBE and BTEX compounds. Techniques will include gas chromatography (GC), gas chromatography-mass spectrometry (GCMS), stable isotopes both bulk and gas chromatography-isotope ratio mass spectrometry (GCIRMS). There are other techniques being used but in a paper of this length we will limit ourselves to these widely used techniques and those applications mentioned above since space does not permit a comprehensive review of all of them
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Organosulphur compounds in coals as determined by reaction with Raney nickel and microscale pyrolysis techniques. Quarterly report, January 1, 1995--March 31, 1995
This report briefly descibes a method for cleaving organosulfur compounds from coal, kerogens and asphaltenes. The technique utilized nickel chloride and sodium borohydride. Experiments were performed on Illinois No. 6 coal. The method was also used in a deuterium labelling technique for investigating sulfur bonds
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Organosulphur compounds in coals as determined by reaction with Raney nickel and microscale pyrolysis techniques. Quarterly report, 1 July 1995--31 October 1995
As well as studying coal samples from Oklahoma and Missouri States, we have now completed the preliminary part of a study of a well known high organosulphur containing coal, Illinois No. 6. As a number of other research groups have used Illinois No. 6 for study, we thought it wise to also analyse this coal for comparison of our method with existing data reported in the literature. To date, analyses of the aliphatic fractions of the free maltene components and the aliphatic hydrocarbons isolated following desulphurization of the free maltene polar fraction, asphaltenes and pre-extracted coal matrix have been performed in duplicate. So far, most of these samples have been analysed by GC and subsequently quantified using n-C{sub 24}D{sub 50}. As Figures 1 and 2 show, the duplicates for the desulphurized products (e.g. Figure 2a and 2b of desulphurized asphaltenes) while showing broad similarities, do not appear to be identical. This is emphasized by differences in the yields of n-alkanes generated, quantified in Table 1. Abundance of corresponding n-alkanes are often quite variable for duplicate analyses, which have been normalized to the quantity of original starting material. While inhomogeneity of sampling can easily explain the variation in abundance of products generated for the asphaltenes and coal matrix, the same cannot be said for the free polar compounds, which dissolve easily in the methanol/tetrahydrofuran solvent system used in the desulphurization process. It would therefore appear that desulphurization experiments should be performed at the very least, in duplicate to gain a clear impression of the distribution and abundance of aliphatic products cleaved from organosulphur compounds. The GC analysis also appears to show that there are different organosulphur compound precursors trapped in the different fractions of the coals