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31.
Due to the increased urgency with which environmental issues are currently being prioritized, business sectors such as construction, that have been identified as one of the largest consumers of raw materials and energy, are actively involved in research aiming to optimize construction processes and products in terms of environmental impact. Although researchers have pointed out various issues and aspects of a construction project’s delivery process that can significantly affect its environmental impact, the extent to which these issues can influence the total environmental impact of the project is unclear. The current research aims to investigate and eventually quantify the influence of a number of such parameters, utilizing an existing steel-framed building as the basis for the necessary calculations. The conclusions drawn illustrate the actual extent of the influence of the examined life cycle parameters, while also offering specific insight in regard to the determination of criteria that can be used as the basis for recommendations for similar projects.  相似文献   
32.
Mountains of the northern Mediterranean basin face two major threats under global change. Aridity and available fuel are both expected to increase because of climatic and land-use changes, increasing fire danger. There may already be signs of such effects in the case of the Pinus nigra and Abies cephalonica forests on Mt. Taygetos (southern Greece). We reconstructed climate (mid- to late-fire-season drought) using tree-rings for the last 150 years and compared it with the mountain’s fire history reconstructed from P. nigra fire scars. Seven, out of the ten, large fires Mt. Taygetos experienced were associated with below-normal precipitation (P) or above-normal maximum temperature (T max). The largest fires occurred in late summer of 1879, 1944, 1998, and 2007. However, only the recent fires (1998 and 2007) had both low P and high T max, also confirmed from long-term meteorological data. The synergy between climate and fuel availability may explain the very high intensity of 1998 and 2007 fires that burned mostly as stand-replacing crown fires. The other two large fire events (1879 and 1944) most likely occurred under reduced availability in burning fuel and were related to above-normal T max. Our findings are among the first based on long-term and site-specific empirical data to support the prediction that Mediterranean mountainous areas will face a very large threat from wildfires in the twenty-first century, if socioeconomic changes leading to land abandonment and thus burning fuel accumulation are combined with the drought intensification projected for the region under global warming.  相似文献   
33.
This paper focuses on the environmental monitoring of radon in soil as a potential trace gas in the search of earthquake precursors. The paper reports the following: (a) Pre-monitoring experiments. (b) Set-up of methods and devices. (c) Active and passive monitoring results concentrating on two extremely-strong radon anomalies (~ 500 kBq m(-3)). (e) Discussion regarding the employed ± 2σ technique for identifying radon disturbances. (f) Application of wavelet-power-spectrum fractal analysis for detecting power-law behaviour. The strong anomalies exhibited anti-persistent power-law-beta-values (b = (1.8 ± 0.2), b = (1.8 ± 0.3)) significantly higher than those of the baseline. Persistent b-values were also detected. The findings comply with a self-organised-critical pre-earthquake state. (h) Discussion on models that interpret the radon anomalies focusing on the recently-proposed asperity-model. (i) Application of a recent technique which showed that the two strong disturbances were proportional to the strain change. It was concluded that the strong radon disturbances may be linked to the strong earthquake of 8/6/2008, M = 6.5, occurred 29 km away from the installed instrumentation.  相似文献   
34.
Despite the long-time application of organic waste derived composts to crops, there is still no universally accepted index to assess compost maturity and stability. The research presented in this article investigated the suitability of seven types of seeds for use in germination bioassays to assess the maturity and phytotoxicity of six composts. The composts used in the study were derived from cow manure, sea weeds, olive pulp, poultry manure and municipal solid waste. The seeds used in the germination bioassays were radish, pepper, spinach, tomato, cress, cucumber and lettuce. Data were analyzed with an analysis of variance at two levels and with pair-wise comparisons. The analysis revealed that composts rendered as phytotoxic to one type of seed could enhance the growth of another type of seed. Therefore, germination indices, which ranged from 0% to 262%, were highly dependent on the type of seed used in the germination bioassay. The poultry manure compost was highly phytotoxic to all seeds. At the 99% confidence level, the type of seed and the interaction between the seeds and the composts were found to significantly affect germination. In addition, the stability of composts was assessed by their microbial respiration, which ranged from approximately 4 to 16 g O2/kg organic matter and from 2.6 to approximately 11 g CO2–C/kg C, after seven days. Initial average oxygen uptake rates were all less than approximately 0.35 g O2/kg organic matter/h for all six composts. A high statistically significant correlation coefficient was calculated between the cumulative carbon dioxide production, over a 7-day period, and the radish seed germination index. It appears that a germination bioassay with radish can be a valid test to assess both compost stability and compost phytotoxicity.  相似文献   
35.
The aim of this paper was to study the variations of radon and daughter nuclei during treatment in the thermal spas of Lesvos Island (Greece). For this purpose, in the thermal spas of Lesvos we have measured the radon concentrations of thermal waters, as well as indoor radon, daughter and coarse particle (>500 nm) concentrations. Various instruments and procedures were employed for measurements. Radon concentrations of thermal waters were found to lie in the range 10 Bq l(-1) and 304 Bq l(-1). Concentration peaks both for radon, radon daughter and coarse particle, were found to appear during filling of baths in the treatment process. The doses delivered to the bathers during treatment were in the range of 0.00670-0.1279 mSv per year, while the doses delivered to personnel were below 20 mSv per year.  相似文献   
36.
In Europe, the establishment of the Natura 2000 network is one of the main actions that has been undertaken to contribute to the maintenance of biodiversity. However, the management system of sites included in the network is under question. The aim of this study was to assess the natural resource management applied to the National Park of the wetlands Kotychi-Strofylia, southern Greece, an important site belonging to the European ecological network Natura 2000, and the Ramsar convention. The methodological approach applied follows the general framework of International Unit for Nature Conservation/World Committee for Protected Areas (IUCN/WCPA) for the evaluation of protected areas, and it was based on field monitoring data with a view of providing information in achieving the stated management objectives. Two levels of indicators were used: the first concerned the evaluation of the management process and the second the evaluation of the management outputs and outcomes. The assessment of the natural resources management in the National Park showed that the management of the area is oriented towards biodiversity conservation and lies within the scope of the habitat directive and the ecological network Natura 2000. The framework applied and the methodological approach followed in this study appear to provide a useful basis for designing and conducting management evaluation. The indicators used at local scale can be integrated at regional- and national-scale projects of management evaluation, and, at the same time, the evaluation results can help local managers to improve management by taking the appropriate management measures. The analytical hierarchical conceptual flow suggested seems to be considered as an essential tool for evaluating natural resource management.  相似文献   
37.
The photo-induced degradation of naphthalene, 1,4-naphthoquinone, 1-naphthol and 1-NO2 naphthalene, adsorbed on silica gel, and with the addition of nitrogenous air pollutants e.g. NO2 (as KNO2) was investigated. Results indicate that compounds adsorbed onto a solid carrier are degraded when irradiated with UV light (λ > 290 nm) in the presence of nitrites. The key species initiating the naphthalene degradation is the OH-radical which is generated through the photolysis of NO2. Reaction products identified were 2-formyl-cinnamaldehyde, 1,4-naphthoquinone, nitronaphthol, o-phthaldialdehyde, phthalide and nitronaphthalene. A mass balance between 40–50% was achieved. Under the same irradiation conditions, 1-NO2 naphthalene is mainly degraded by direct photolysis while degradation of 1-naphthol and 1,4-naphthoquinone proceeds via the reaction with OH-radicals. Identified products were hydroxy-nitro-nitroso- and quinones compounds.  相似文献   
38.
The current examination dealt with the development of a methodology to produce quercetin, a multifunctional bio-flavonoid, by designing task-specific, highly acidic deep eutectic solvents, based on glycerol and natural organic acids. The purpose was to achieve a simultaneous hydrolysis of spiraeoside, the major quercetin glycoconjugate occurring in onion solid wastes, and quercetin extraction. After an initial performance screening, the combination of glycerol/oxalic acid was identified as the highest-performing system, and further investigation showed that the most efficacious molar ratio was glycerol/oxalic acid 3:1. Further study of hydrolysis/extractions conditions suggested 30 min, at 130°C, to be the best operating conditions, giving the highest yield of 19.65 mg quercetin per grams of dry mass. The extract obtained under these conditions displayed significantly enhanced antiradical activity, compared to control extracts prepared with water or aqueous ethanol. On the other hand, results on the ferric-reducing power were rather contradictory. It is proposed that such a methodology may be implemented to valorize onion solid wastes, for the production of extracts significantly enriched in quercetin, with increased antiradical properties.  相似文献   
39.
The use of biopurification systems can mitigate the effects of pesticide contamination on farms. The primary aim of this study was to evaluate the effect of pesticide dissipation on microbial communities in a pilot biopurification system. The pesticide dissipation of atrazine, chlorpyrifos and iprodione (35 mg kg?1 active ingredient [a.i.]) and biological activity were determined for 40 days. The microbial communities (bacteria, actinomycetes and fungi) were analyzed using denaturing gradient gel electrophoresis (DGGE). In general, pesticide dissipation was the highest by day 5 and reached 95%. The pesticides did not affect biological activity during the experiment. The structure of the actinomycete and bacterial communities in the rhizosphere was more stable during the evaluation than that in the communities in the control without pesticides. The rhizosphere fungal communities, detected using DGGE, showed small and transitory shifts with time. To conclude, rhizosphere microbial communities were not affected during pesticide dissipation in a pilot biopurification system.  相似文献   
40.
Emitted pollutants from the Agios Dimitrios lignite-fired power plant in northern Greece show a very strong linear correlation with the free calcium oxide content of the lignite ash. Dust (fly ash) emissions are positively correlated to free calcium oxide content, whereas sulfur dioxide (SO2) emissions are negatively correlated. As a result, at present, the Agios Dimitrios Power Plant operates very strictly within the legislative limits on atmospheric particulate emission. In the present study, the factors to be considered in assessing the impact of lignite combustion on the environment are presented and evaluated statistically. The ash appears to have a remarkable SO2 natural dry scrubbing capability when the free calcium oxide content ranges between 4 and 7%. Precipitator operating problems attributable to high ash resistivity can be overcome by injecting sulfur trioxide to reduce the ash resistivity, with, of course, a probable increase in operating costs.  相似文献   
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