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This paper deals with the 2007 wildfires that hit Peloponnesus, the southern peninsula of Greece, presenting an overview of the impacts in terms of infrastructural damages and human injuries and losses. Network performance and components’ criticality analyses are used to assess the effects of the fires in vehicular traffic and the overall transport network. The crisis and emergency management of the event are discussed in depth, highlighting potential gaps and possibilities for future improvement. The paper concludes with a presentation of the adaptation measures that succeeded the event in terms of recovery plans, national efforts on fire prevention programs and wildfire management.  相似文献   
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The present study reports on the preliminary investigation of three low-cost natural materials with respect to their chromium(VI) removal efficiency from contaminated water. The tested materials were reed, in milled and chopped form, compost, and dewatered sludge from a municipal wastewater treatment plant. The chromium(VI) removal capacity of the aforementioned materials was investigated by simulating the physicochemical conditions prevailing in a stormwater outfall flowing into the Asopos River in Inofyta, Central Greece. Thus, batch and column experiments were carried out using solutions of 3–5 mg/L chromium(VI) and pH value 8.5 ± 0.5. The results showed that the tested materials were capable of removing 3 mg/L chromium(VI), however by allowing different contact times for each material. The chromium(VI) removal kinetics were studied through batch experiments, and reed was found to be the most efficient material. Therefore, at a second series of batch and up-flow column experiments, the effect of the liquid-to-solid ratio, pH, and contact time on chromium(VI) removal using chopped reed was investigated. Chromium(VI) removal took place through both reduction and adsorption mechanisms, while the released soluble organic matter from reed seemed to favor the reduction mechanism. As a result, reed is a potential biosorbent capable of treating heavily chromium(VI)-contaminated water flows, although a high mass of reed is required for a treatment process, such in the case of the stormwater discharged into Asopos River.  相似文献   
3.
This paper aims to reconcile discrepancies among reports of dechlorination performance in the presence of sulfate, by analyzing data from the literature, presenting results from laboratory experiments performed with mixed anaerobic microbial cultures, and synthesizing respective findings. A complete set of metrics for dechlorination progress was developed and used in the analysis of selected field and laboratory studies. When differences in site and experimental conditions are accounted for and definitions of dechlorination completeness are harmonized, the inverse relationship between dechlorination performance and sulfate concentration becomes clearer. This relationship was investigated in detail with laboratory experiments on mixed anaerobic microbial cultures enriched with the same concentration of trichloroethylene (TCE) and different sulfate concentrations, equal to near zero (considered as the baseline culture), 30, 400, and 1100 mg/L. In all experiments, sulfate reduction proceeded concurrently with dechlorination. The observed behavior was bimodal, indicating a transition in dechlorination performance between 30 and 400 mg/L. Under low donor to acceptor stoichiometry conditions, TCE dechlorination was incomplete in all experiments after 14 days, while the percentage of TCE moles reduced to vinyl chloride was lower by about 50% in the experiments with high sulfate concentrations. When donor was added in excess to stoichiometry needs for TCE reduction, TCE dechlorination was complete in the baseline culture, while only little ethene was detected in the high sulfate concentration cultures. When all studies are considered together, it appears that the presence of sulfate does not preclude complete dechlorination but rather delays it. Data analysis also suggests that the proposed upper limit of 500 mg/L for the range of initial sulfate concentration that is not problematic for dechlorination should be revised to a lower value.  相似文献   
4.
The post-starburst region B in M82 and its massive star cluster component have been the focus of multiple studies, with reports that there is a large population of coeval clusters of age ~1 Gyr, which were created with a Gaussian initial mass distribution. This is in disagreement with other studies of young star clusters, which invariably find a featureless power-law mass distribution. Here, we present Gemini-North optical spectra of seven star clusters in M82-B and show that their ages are all between 10 and 300 Myr (a factor of 3–100 younger than previous photometric results) and that their extinctions range between near zero and 4 mag (A V ). Using new HST ACS-HRC U-band observations we age date an additional ~30 clusters whose ages/extinctions agree well with those determined from spectroscopy. Completeness tests show that the reported ‘turn-over’ in the luminosity/mass distributions is most likely an artefact, due to the resolved nature of the clusters. We also show that the radial velocities of the clusters are inconsistent with them belonging to a bound region.  相似文献   
5.
Self-potential is a passive geophysical method that can be applied in a straightforward manner with minimum requirements in the field. Nonetheless, interpretation of self-potential data is particularly challenging due to the inherited non-uniqueness present in all potential methods. Incorporating information regarding the target of interest can facilitate interpretation and increase the reliability of the final output. In the current paper, a novel method for detecting multiple sheet-like targets is presented. A numerical framework is initially described that simulates sheet-like bodies in an arbitrary 2D resistivity distribution. A scattered field formulation based on finite differences is employed that allows the edges of the sheet to be independent of the grid geometry. A novel analytical solution for two-layered models is derived and subsequently used to validate the accuracy of the proposed numerical scheme. Lastly, a hybrid optimization is proposed that couples linear least-squares with particle-swarm optimization in order to effectively locate the edges of multiple sheet-like bodies. Through numerical and real data, it is proven that the hybrid optimization overcomes local minimal that occurs in complex resistivity distributions and converges substantially faster compared to traditional particle-swarm optimization.  相似文献   
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