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Following the withdrawal of IFRIC 3: Emissions Rights in 2005, European Union (EU) companies participating in an EmissionsTrading Scheme (ETS) do not have definitive guidelines as to how to account for carbon emissions allowances. Using a content analysis methodology, this study examines the disclosed accounting policies of companies participating in the EU ETS, and reveals how, in the absence of clear guidance, they account for their carbon emissions allowances. As the accounting method adopted will impact upon a company's financial statements, these findings are of interest to accounting standards setters, investors, financial reporting preparers, auditors, and researchers.

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To investigate the potential for mobilizing organic compounds from coal beds during geologic carbon dioxide (CO 2 ) storage (sequestration), a series of solvent extractions using dichloromethane (DCM) and using supercritical CO 2 (40°C and 10 MPa) were conducted on a set of coal samples collected from Louisiana and Ohio. The coal samples studied range in rank from lignite A to high volatile A bituminous, and were characterized using proximate, ultimate, organic petrography, and sorption isotherm analyses. Sorption isotherm analyses of gaseous CO 2 and methane show a general increase in gas storage capacity with coal rank, consistent with findings from previous studies. In the solvent extractions, both dry, ground coal samples and moist, intact core plug samples were used to evaluate effects of variations in particle size and moisture content. Samples were spiked with perdeuterated surrogate compounds prior to extraction, and extracts were analyzed via gas chromatography−mass spectrometry. The DCM extracts generally contained the highest concentrations of organic compounds, indicating the existence of additional hydrocarbons within the coal matrix that were not mobilized during supercritical CO 2 extractions. Concentrations of aliphatic and aromatic compounds measured in supercritical CO 2 extracts of core plug samples generally are lower than concentrations in corresponding extracts of dry, ground coal samples, due to differences in particle size and moisture content. Changes in the amount of extracted compounds and in surrogate recovery measured during consecutive supercritical CO 2 extractions of core plug samples appear to reflect the transition from a water-wet to a CO 2 -wet system. Changes in coal core plug mass during supercritical CO 2 extraction range from 3.4% to 14%, indicating that a substantial portion of coal moisture is retained in the low-rank coal samples. Moisture retention within core plug samples, especially in low-rank coals, appears to inhibit accessibility of supercritical CO 2 to coal matrix porosity, limiting the extent to which hydrocarbons are mobilized. Conversely, the enhanced recovery of some surrogates from core plugs relative to dry, ground coal samples might indicate that, once mobilized, supercritical CO 2 is capable of transporting these constituents through coal beds. These results underscore the need for using intact coal samples, and for better characterization of forms of water in coal, to understand fate and transport of organic compounds during supercritical CO 2 injection into coal beds. ■ INTRODUCTIONThe physical properties of coal have important applications to quantifying the potential for hydrocarbon generation, retention, and expulsion from coal beds, understanding interactions of injected CO 2 with coal during geologic CO 2 storage (sequestration), and recovering hydrocarbons, such as during enhanced coalbed methane recovery. Coal generally is described as a three-dimensional, cross-linked polymer containing fluid phases within network porosity, i.e., cleats (fractu...