996 resultados para Oil shales


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Thousands of the world's offshore oil and gas structures are approaching obsolescence and will require decommissioning within the next decade. Many nations have blanket regulations requiring obsolete structures to be removed, yet this option is unlikely to yield optimal environmental, societal and economic outcomes in all situations. We propose that nations adopt a flexible approach that allows decommissioning options to be selected from the full range of alternatives (including 'rigs-to-reefs' options) on a case-by-case basis. We outline a method of multi-criteria decision analysis (Multi-criteria Approval, MA) for evaluating and comparing alternative decommissioning options across key selection criteria, including environmental, financial, socioeconomic, and health and safety considerations. The MA approach structures the decision problem, forces explicit consideration of trade-offs and directly involves stakeholder groups in the decision process. We identify major decommissioning options and provide a generic list of selection criteria for inclusion in the MA decision process. To deal with knowledge gaps concerning environmental impacts of decommissioning, we suggest that expert opinion feed into the MA approach until sufficient data become available. We conducted a limited trial of the MA decision approach to demonstrate its application to a complex and controversial decommissioning scenario; Platform Grace in southern California. The approach indicated, for this example, that the option 'leave in place intact' would likely provide best environmental outcomes in the event of future decommissioning. In summary, the MA approach will allow the environmental, social, and economic impacts of decommissioning decisions to be assessed simultaneously in a transparent manner. © 2013 Elsevier Ltd.

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This study provides the first assessment of fish associations with oil and gas structures located in deep water (85-175 m) on Australia's north-west continental shelf, using rare oil industry video footage obtained from remotely operated vehicles. A diverse range of taxa were observed associating with the structures, including reef-dependent species and transient pelagic species. Ten commercially fished species were observed, the most abundant of which was Lutjanus argentimaculatus, with an estimated biomass for the two deepest structures (Goodwyn and Echo) of 109 kg.

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In this paper, we investigate the psychological barrier effect induced by the oil price on firm returns when the oil price reaches US$100 or more per barrel. We find evidence of the negative effect of the US$100 oil price barrier for: (a) the entire sample of 1559 firms listed on the American stock exchanges; (b) both foreign and domestic firms, with domestic firms significantly more affected; (c) the 10 different sizes of firms, with the smaller firms less affected compared to the larger firms; and (d) 17 sectors of firms, with firms in the utilities, mining, and administration sectors being the least affected.

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The microencapsulation of tuna oil in gelatin-sodium hexametaphosphate (SHMP) using complex coacervation was optimised for the stabilisation of omega-3 oils, for use as a functional food ingredient. Firstly, oil stability was optimised by comparing the accelerated stability of tuna oil in the presence of various commercial antioxidants, using a Rancimat™. Then zeta-potential (mV), turbidity and coacervate yield (%) were measured and optimised for complex coacervation. The highest yield of complex coacervate was obtained at pH 4.7 and at a gelatin to SHMP ratio of 15:1. Multi-core microcapsules were formed when the mixed microencapsulation system was cooled to 5 °C at a rate of 12 °C/h. Crosslinking with transglutaminase followed by freeze drying resulted in a dried powder with an encapsulation efficiency of 99.82% and a payload of 52.56%. Some 98.56% of the oil was successfully microencapsulated and accelerated stability using a Rancimat™ showed stability more than double that of non-encapsulated oil.

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This chapter focuses on the specific case of the Iraqi Federation of Oil Unions (IFOU), Iraq’s largest and most powerful independent workers’ union. Leaving aside IFOU’s resistance of foreign occupation and its fight against privatisation, this chapter focuses on the tensions between IFOU and the Maliki government and examines the extent to which IFOU has served as a bulwark against the state’s rising authoritarianism. The chapter begins with a brief history of Iraqi trade unions under the Baathist regime and concludes by arguing that examples of civil society movements such as IFOU are perhaps Iraq’sonly real hope for genuine democratisation.

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Superhydrophilic and superoleophobic materials are very attractive for efficient and cost-effective oil-water separation, but also very challenging to prepare. Reported herein is a new superamphiphobic coating that turns superhydrophilic and superoleophobic upon ammonia exposure. The coating is prepared from a mixture of silica nanoparticles and heptadecafluorononanoic acid-modified TiO2 sol by a facile dip-coating method. Commonly used materials, including polyester fabric and polyurethane sponge, modified with this coating show unusual capabilities for controllable filtration of an oil-water mixture and selective removal of water from bulk oil. We anticipate that this novel coating may lead to the development of advanced oil-water separation techniques.

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Partial hydrolysis of emu oil was performed using Thermomyces lanuginosus lipase to remove some shorter chain fatty acids. Then eicosapentaenoic acid (EPA) was incorporated into the modified emu oil using either Lipozyme RMIM or Lipozyme TLIM to produce new EPA enriched structured lipids. Using Isooctane as a reaction solvent increased the level of EPA incorporation, which was higher with RMIM than with TLIM. TLIM incorporated EPA almost exclusively into the sn-1,3 positions, whereas RMIM incorporated EPA at sn-1,3 and sn-2 positions in an almost statistical ratio. Both structured lipids were less oxidatively stable than emu oil.

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 The author isolated and characterized several Thraustochytrid strains from Indian and Australian marine biodiversity and compared these strains for their application in biodiesel and DHA production depend on their fatty acid profile. Strain having best productivity was further optimized for the coproduction of DHA and biodiesel.

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The current study introduces the water-soluble complexes containing hydrophobically associating copolymer and a series of surface activity imidazolium-based ionic liquids (CnmimBr, n=6, 8, 10, 12, 14 and 16). The polymer, denoted as PAAD, was prepared with acrylamide (AM), acrylic acid (AA) and N,N-diallyl-2-dodecylbenzenesulfonamide (DBDAP). And the hydrophobic associative behavior of PAAD was studied by a combination of the pyrene fluorescence probe and viscosimetry. Incorporation of CnmimBr (n=10, 12, 14 and 16) in PAAD leaded to the white thick gel, while the pellucid solutions were obtained in complexes of PAAD and CnmimBr (n=6 and 8); addition of C6mimBr around critical micelle concentration resulted in a large decrease in viscosity of solution. Therefore, we particularly investigated the performance of PAAD/C8mimBr complex. The interfacial tension of PAAD/C8mimBr complex solution and crude oil under different conditions was examined. Moreover, PAAD/C8mimBr complex exhibited superior temperature resistance and shear reversible performance for enhancing oil recovery (EOR) by rheological test. The promising EOR of 21.65% can be obtained by PAAD/C8mimBr complex showing high potential to utilize this kind of new complex in EOR processes.

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The recommendations on the intake of long chain omega-3 polyunsaturated fatty acids (n-3 LC-PUFA) vary from eating oily fish ("once to twice per week") to consuming specified daily amounts of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) ("250-500 mg per day"). It is not known if there is a difference in the uptake/bioavailability between regular daily consumption of supplementsvs. consuming fish once or twice per week. In this study, the bioavailability of a daily dose of n-3 LC-PUFA (Constant treatment), representing supplements, vs. a large weekly dose of n-3 LC-PUFA (Spike treatment), representing consuming once or twice per week, was assessed. Six-week old healthy male Sprague-Dawley rats were fed either a Constant treatment, a Spike treatment or Control treatment (no n-3 LC-PUFA), for six weeks. The whole body, tissues and faeces were analysed for fatty acid content. The results showed that the major metabolic fate of the n-3 LC-PUFA (EPA+docosapentaenoic acid (DPA) + DHA) was towards catabolism (β-oxidation) accounting for over 70% of total dietary intake, whereas deposition accounted less than 25% of total dietary intake. It was found that significantly more n-3 LC-PUFA were β-oxidised when originating from the Constant treatment (84% of dose), compared with the Spike treatment (75% of dose). Conversely, it was found that significantly more n-3 LC-PUFA were deposited when originating from the Spike treatment (23% of dose), than from the Constant treatment (15% of dose). These unexpected findings show that a large dose of n-3 LC-PUFA once per week is more effective in increasing whole body n-3 LC-PUFA content in rats compared with a smaller dose delivered daily.

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Herein, we report a novel acrylamide copolymer with antimicrobial property as an enhanced oil recovery chemical. The copolymer was synthesized from acrylamide (AM), acrylic acid (AA) and 2-((2-(acryloyloxy)ethyl)dimethylammonio)ethyl sulfite (ADMES) using oxidation-reduction initiation system. Subsequently, the copolymer AM/AA/ADMES was evaluated and characterized on several aspects such as IR, 1H NMR, intrinsic viscosity, and dissolubility. The AM/AA/ADMES solution exerted remarkable thickening ability, salt tolerance ability and viscoelasticity. In addition, the rheological properties, temperature resistance ability and long-term stability of AM/AA/ADMES were investigated systematically in the presence of sulfate-reducing bacteria and relatively low viscosity loss could be obtained compared to partially hydrolyzed polyacrylamide. On the basis of core flooding experiments, AM/AA/ADMES was found to be a valuable prospect with 10.5 resistance factor, 4.6 residual resistance factor and up to 11.0% enhanced oil recovery.

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Oil spills cause serious damage to the aquatic ecosystem and require quick cleanup. Herein we report high internal phase emulsion (HIPE) xerogels for the first time as oil absorbents for enhanced oil spill recovery. The HIPE xerogels absorb diesel from the water-oil mixture in 20-30 seconds. The absorption capacity of the HIPE xerogels ranges from 20 to 32 times for different kinds of oils, and the oils can be recovered simply by being squeezed out, with a recovery rate around 80%. They can be reused at least 40 times without obvious deterioration in oil separation properties from 0 to 45 °C. These novel xerogels are suitable for practical use in oil spill reclamation and wastewater treatment.

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This paper investigates the price volatility interaction between the crude oil and equity markets in the US using 5-min data over the period 2009-2012. Our main findings can be summarised as follows. First, we find strong evidence to demonstrate that the integration of the bid-ask spread and trading volume factors leads to a better performance in predicting price volatility. Second, trading information, such as bid-ask spread, trading volume, and the price volatility from cross-markets, improves the price volatility predictability for both in-sample and out-of-sample analyses. Third, the trading strategy based on the predictive regression model that includes trading information from both markets provides significant utility gains to mean-variance investors.