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Incineration is the main option for residual Municipal Solid Waste treatment in France. This study compares the environmental performances of 110 French incinerators (i.e. 85% of the total number of plants currently in activity in France) in a Life Cycle Assessment perspective, considering 5 non-toxic impact categories: climate change, photochemical oxidant formation, particulate matter formation, terrestrial acidification and marine eutrophication. Mean, median and lower/upper impact potentials are determined considering the incineration of 1 tonne of French residual Municipal Solid Waste. The results highlight the relatively large variability of the impact potentials as a function of the plant technical performances. In particular, the climate change impact potential of the incineration of 1 tonne of waste ranges from a benefit of ?58 kg CO2-eq to a relatively large burden of 408 kg CO2-eq, with 294 kg CO2-eq as the average impact. Two main plant-specific parameters drive the impact potentials regarding the 5 non-toxic impact categories under study: the energy recovery and delivery rate and the NOx process-specific emissions. The variability of the impact potentials as a function of incinerator characteristics therefore calls for the use of site-specific data when required by the LCA goal and scope definition phase, in particular when the study focuses on a specific incinerator or on a local waste management plan, and when these data are available.  相似文献   
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In the goal of finding efficient scavengers for radioiodide in conditions (pH, pE) close to those encountered in deep geological sites, sorption of iodide ions on cuprous sulfide minerals (especially roxbyite, Cu(1.75)S) has been studied. Surface analysis by X-ray photoelectron spectroscopy has shown that commercial cuprous sulfides are covered by an oxidized overlayer (mainly in the form of CuSO(4)). Therefore, a synthetic procedure to get roxbyite (typically by mixing Na(2)S with an aqueous suspension of commercial Cu(2)O) was applied to produce pure samples with clean surfaces. Batch equilibration of cuprous sulfide particles suspended in aqueous solutions containing iodide species has revealed significant consumption of iodide. The sorption mechanism involves the formation of a surface complex via the exchange of surface hydroxyl groups by iodide anions, as highlighted by a transient pH increase during the immobilization process. Other copper and mixed copper-iron sulfides (e.g. CuS, CuFeS(2)), which are stable over wide pH and potential ranges are also likely to accumulate iodide species. Because of the specific interaction between iodide and copper(I) centers on the minerals, high distribution coefficients (>1000 ml/g) were observed.  相似文献   
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Summary In parasitoid wasps, self-superparasitism (oviposition into a host already parasitized by the female herself) often contributes less to the reproductive success of the parasitoid than oviposition into a host previously parasitized by a conspecific (conspecific superparasitism). It could therefore often be profitable for parasitoids to avoid self-superparasitism. This requires a mechanism for either (1) the avoidance of previously searched areas and/or (2) the rejection of hosts containing eggs laid by the searching female. We investigated whether the solitary parasitoid Epidinocarsis lopezi is able to avoid self-superparasitism. We show that visits to previously searched patches were shorter than visits to unsearched patches and conclude that E. lopezi females leave a trail odour on patches they have searched. No differences were found between the time on patches previously searched by the wasp itself and on patches visited by conspecifics. However, E. lopezi superparasitizes fewer hosts previously parasitized by itself than hosts parasitized by a conspecific. Thus, they recognize an individual-specific mark in or on the host. We discuss how patch marking and host marking enable E. lopezi to avoid self-superparasitism.  相似文献   
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Summary Seventeen red squirrels (Tamiasciurus hudsonicus) were displaced and released about 600 or 2000 m from their home site, and the routes they followed during several hours after release were recorded. The analysis of these routes shows that, in their first attempts to leave the release site area, the squirrels' orientation is non-random with respect to the home direction (Fig. 2a). However, after a few hundred meters in this initial direction, the animals tend to go back to the release site area, and then to perform a series of radial forays centered on the latter.The results suggest that, in the conditions of the experiment, the squirrels have some information on the direction, but not on the distance to the home site. Their behavior appears to be governed by two complementary (but occasionally conflicting) strategies, one being to use the directional information available, the other not to proceed further than a distance which corresponds to the distance normally covered in spontaneous exploratory trips. It is argued that this double strategy is appropriate for spontaneous homing trips consecutive to an exploratory foray.  相似文献   
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Vertical profiles of physical, chemical and phytoplanktonic parameters are described, at the level of the thermocline, in the area of Banyuls-sur-Mer, France. The results show that the thermocline divides two masses of water: (1) Mediterranean surface water with low nutrient concentrations and a salinity below 38.00 ‰; (2) deep, nutrient-rich upwelled water (N?NO3 >3 μat-g·l-1, P?PO4>0.3 μat-g·l-1, >38.30 ‰ S), which comes from the upper limit of the Mediterranean intermediate water, usually located at the 200 m level. Consequently, conditions are suitable for high production rates at the bottom of the thermocline, where Chl a is above 0.5 mg·m-3; dominant species are Nitzschia delicatissima and N. pungens. A diagram is presented explaining the different effects of the pycnoclines on primary production: eutrophication at the pycnocline levels is the result of passive accumulation of phytoplankton and organic matter during sedimentation, and/or of reduced diffusion of nutrients from deep waters towards the surface.  相似文献   
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Jacques Henry 《Disasters》2011,35(1):220-242
For some time, disaster researchers have looked for social change and mostly found continuity. This paper argues that shifting the focus from investigating social change to documenting continuity may enhance the understanding and planning of post‐disaster situations especially in industrialised societies like the United States. Drawing from qualitative data from post‐Katrina New Orleans, it proposes using the concept of continuity as an analytical device both to identify the axes of continuity and evaluate the likelihood and possible dimensions of social change. The analysis of long‐term recovery plans, along with field observations and interviews with evacuees, suggest that despite the well‐documented emergence of conflict in post‐Katrina New Orleans, the likelihood of social change appears limited.  相似文献   
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Demolition wastes are generally disposed of in unlined landfills for inert waste. However, demolition wastes are not just inert wastes. Indeed, a small fraction of demolition waste contains components that are hazardous to human health and the environment, e.g., lead-based paint, mercury-contained in fluorescent lamps, treated wood, and asbestos. The objective of this study is to evaluate the release potential of pollutants contained in these hazardous components when they are mixed with inert wastes in unlined landfills. After identification of the different building products which can contain hazardous elements and which can be potentially pollutant in landfill scenario, we performed leaching tests using three different lysimeters: one lysimeter containing only inert wastes and two lysimeters containing inert wastes mixed with hazardous demolition wastes. The leachates from these lysimeters were analysed (heavy metals, chlorides, sulphates fluoride, DOC (Dissolved Organic Carbon), phenol index, and PAH). Finally, we compared concentrations and cumulative releases of elements in leachates with the limits values of European regulation for the acceptance of inert wastes at landfill. Results indicate that limit values are exceeded for some elements. We also performed a percolation column test with only demolition hazardous wastes to evaluate the specific contribution of these wastes in the observed releases.  相似文献   
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