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A preliminary study for a source–sink match for application of Carbon Capture and Storage (CCS) in Portugal is presented. The location of the main CO2 emission sources in Portugal, existing and planned, was analysed and three main source clusters, emitting a total of 26.8 Mt/year, were defined. The three source clusters are connected by a natural gas pipeline network.CO2 storage reservoirs are likely to be restricted to deep saline formations. Potential storage formations are described in the Porto, Lusitanian and Algarve sedimentary basins. Due to the large continental shelf, composed mainly of sedimentary rocks, it is important to consider offshore opportunities. A Geographical Information System (GIS), including information on the stratigraphy, seismicity, neotectonics and geothermal features, was used for prioritising the areas where reservoir identification and characterization studies should be conducted. Despite not showing the most promising geological conditions, the area around the deepwater harbour of Sines is given the highest priority, since sources in the area account for more than 40% of point source emissions in Portugal.  相似文献   
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The aim of this article is to analyze how the implementation of the environmental management system (EMS) in accordance with the ISO 14001: 2004 standard has been carried out in organizations having more than one standardized Management System (MSs). In particular, four implementation aspects will be discussed, namely the different management system standards (MSSs) used for registration, for example ISO 14001, ISO 9001, OHSAS 18001, ISO 27001 and SA 8000, the order in which they were implemented, the time required for each implementation, as well as the scope of integration of these MSSs into a single Integrated Management System (IMS).In order to do so, some of the results of a survey carried out in 176 organizations registered to, at a minimum, both ISO 14001: 2004 and ISO 9001: 2000 standards for environmental and quality management, respectively, are presented. As one of the few existing empirical studies regarding the integration of multiple MSs, this research reveals the importance of the different possibilities which organizations can opt for when considering EMS implementation. For example, while most respondents implemented ISO 9001 before ISO 14001, others did so simultaneously or even applied ISO 14001 first. Furthermore, although a large majority of organizations integrated their EMS with additional standardized MSs, a small percentage did not. Apart from illustrating the survey outcomes, the article contains a detailed case analysis of four specific organizations with high environmental awareness that have implemented quality and other standardized MSs.  相似文献   
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Given a differential game, if agents have different time preference rates, cooperative (Pareto optimum) solutions obtained by applying Pontryagin’s maximum principle become time inconsistent. We derive a set of dynamic programming equations in continuous time whose solutions are time-consistent equilibria for problems in which agents differ in their utility functions and also in their time preference rates. The solution assumes cooperation between agents at every time. Since coalitions at different times have different time preferences, equilibrium policies are calculated by looking for Markov (subgame perfect) equilibria in a (noncooperative) sequential game. The results are applied to the study of a cake-eating problem describing the management of a common property exhaustible natural resource. The extension of the results to a simple common property renewable natural resource model in infinite horizon is also discussed.  相似文献   
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Microcystis aeruginosa is a species of freshwater cyanobacteria which can form harmful algal blooms in freshwater water bodies worldwide. However, in spite its sporadic occurrences for short periods of time in estuarine waters, their influence on zooplankton populations present in these ecosystems has not been extensively studied. In this work, Artemia franciscana was used as test organism model, studying mortality against several strains of M. aeruginosa with different degrees of toxigenicity, measuring whole-live cells and homogenate extracts. Results were compared with microcystin-LR equivalent content, measured by immunoassay. The results show that there were no significant differences between both exposure models (whole cells and extracts), and there are significant differences respect to the toxigenicity of cyanobacterial blooms depending of the M. aerugionosa strain involved in the process. Analysis of microcystin-LR equivalent concentration test immediately below the lowest significant concentration in all M. aerugionosa strains was used to determine the potential risk associated with the cell densities during a bloom. Comparison among the selected M. aerugionsa strains show that these factors have influence in the results obtained, and thus, several differences have been evidenced depending of the microcystin-LR equivalent production and the strain type involved.  相似文献   
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Benzene is a carcinogenic air pollutant for which European legislation has set an annual limit and criteria for the number of fixed monitoring sites within air quality networks(AQMN). However, due to the limited number of fixed sites for benzene measurement, exposure data are lacking. Considering the relationship between benzene levels and other variables monitored within an AQMN, such as NO2, O3, temperature, solar radiation, and accumulated precipitation, this study propo...  相似文献   
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