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221.
Journal of Material Cycles and Waste Management - The accumulation of floatable litter load captured in gross pollutant trap (GPT) due to the hydrological runoff has become challenging due to rapid...  相似文献   
222.
There is a growing interest in analyzing the possibility for current nuclear power plants operation extension. In that sense, life management programs, considering safety components ageing, are being developed and employed. On the other side, the large uncertainties of the ageing parameters as well as the uncertainties associated with most of the reliability data collections are widely acknowledged.This paper deals with uncertainty analysis associated with specific ageing rates database. The analysis is conducted using an analytical unavailability model applied for a selected safety system in a nuclear power plant. The most important problem is the immense uncertainty associated to the component ageing data sets as well as the lack of the very data in general, which would correspond to the more detailed modelling of ageing.New probability distributions, encompassing the ageing rates available in the considered data set, are suggested. The obtained results indicate the extent to which the uncertainty of the considered ageing data set, given the inherently assigned probability distribution, influences the performed unavailability calculations. Additionally, comparative analysis regarding the insights gained out of the application of the suggested probability distributions is conducted.  相似文献   
223.
Produced water is a significant waste stream generated in association with oil and gas production. It contains high concentrations of hydrocarbon constituents and different salts. In this study, a membrane sequencing batch reactor (MSBR) was used to treat synthetic and real produced water. The MSBR was evaluated in terms of biodegradation of hydrocarbons in the synthetic produced water with various organic loading rates (OLR) (0.281, 0.563, 1.124, 2.248, and 3.372 kg COD/(m3 day)), cycle time (12, 24, and 48 h), and membrane performance. The effects of salt concentrations at different total dissolved solids (TDS) (35,000, 50,000, 100,000, 150,000, 200,000, and 250,000 mg/L) on biological treatment of the pollutants in the synthetic and real wastewater were studied. At an OLR of 1.124 kg COD/(m3 day), an HRT of 48 h and TDS of 35,000 mg/L, removal efficiencies of 97.5%, 97.2%, and 98.9% of COD, total organic carbon (TOC), and oil and grease (O&G), respectively were achieved. For the real produced water, removal rates of 86.2%, 90.8%, and 90% were obtained for the same conditions. However, with increasing salt content, the COD-removal efficiencies of the synthetic and real produced water were reduced to 90.4% and 17.7%, respectively at the highest TDS.  相似文献   
224.
225.
The Dublin SURGE (Soil Urban Geochemistry) Project is Dublin’s first baseline survey of heavy metals and persistent organic pollutants in topsoils and is part of a Europe-wide initiative to map urban geochemical baselines in ten cities. 1,058 samples were collected as part of a stratified random sampling programme in the greater Dublin area to give an overview of baseline conditions in the city. Samples were analysed for 31 inorganic elements including heavy metals. Analysis of results indicates that the concentrations of lead, copper, zinc and mercury are strongly influenced by human activities, with elevated concentrations in the city docklands, inner city and heavy industry areas. Sources of heavy metals in these areas may include historical industry, coal burning, re-use of contaminated soil, modern traffic and leaded paint and petrol. Concentrations of other inorganic elements in topsoil show patterns which are strongly related to regional bedrock parent material. The spatial distributions of heavy metals, in particular Pb and As, are explored in detail with respect to regional geology and the influence of historical industry on soil quality. Exploratory data, geostatistical and correlation analyses suggest that the concentrations of heavy metals tend to increase as the intensity of historical industrial activity increases. In particular, drinks production, power generation, oil/gas/coal, metals and textile historical industries appear to be the contamination source for several heavy metals. The data provide a geochemical baseline relevant to the protection of human health, compliance with environmental legislation, land use planning and urban regeneration.  相似文献   
226.
Adaptive brain architecture hypotheses predict brain region investment matches the cognitive and sensory demands an individual confronts. Social hymenopteran queen and worker castes differ categorically in behavior and physiology leading to divergent sensory experiences. Queens in mature colonies are largely nest-bound while workers depart nests to forage. We predicted social paperwasp castes would differ in tissue allocation among brain regions. We expected workers to invest relatively more than queens in neural tissues that process visual input. As predicted, we found workers invested more in visual relative to antennal processing than queens both in peripheral sensory lobes and in central processing brain regions (mushroom bodies). Although we did not measure individual brain development changes, our comparative data provide a preliminary test of mechanisms of caste differences. Paperwasp species differ in the degree of caste differentiation (monomorphic versus polymorphic castes) and in colony structure (independent- versus swarm-founding); these differences could correspond to the magnitude of caste brain divergence. If caste differences resulted from divergent developmental programs (experience-expectant brain growth), we predicted species with morphologically distinct queens, and/or swarm-founders, would show greater caste divergence of brain architecture. Alternatively, if adult experience affected brain plasticity (experience-dependent brain growth), we predicted independent-founding species would show greater caste divergence of brain architecture. Caste polymorphism was not related to the magnitude of queen-worker brain differences, and independent-founder caste brain differences were greater than swarm-founder caste differences. Greater caste separation in independent-founder brain structure suggests a role for adult experience in the development of caste-specific brain anatomy.  相似文献   
227.
Finding solutions for complex environmental, economic and social issues in organisations relies on coordinated actions among several social actors that are involved in the sustainable development web and demands that they learn new business methods. In this scenario, which involves multiple social actors, relationships, contexts and interests, social learning has emerged as a hybrid approach to resolving complex environmental and social problems. Such an approach marks a different situation for organisations whose focus is not only on supporting such problem resolution but also on transforming such crises into opportunities to generate sustainable products and services. Thus, this study discusses how one of the largest companies in Latin America’s chemical segment formed a network with 23 social actors and is socially learning to deal with the dialectic between return on investments for its shareholders and benefits for its stakeholders. Research was conducted based on Boje’s narrative analysis. The data was built through interviews, informal conversations, textual and audio-visual documents and non-participant observation. This paper discusses the concept and describes the social learning process for sustainability (in this case, for sustainable agriculture) from the viewpoint of a for-profit organisation. In this manner, this study contributes to strengthening the connection between social learning and sustainability.  相似文献   
228.
Female birds can influence offspring fitness by varying the relative quantities of egg components they deposit within and between clutches. Antimicrobial proteins (lysozyme, ovotransferrin, and avidin) are significant components of the avian albumen and likely aid in defense of embryos from microbial infection. Within clutches, females may enhance antimicrobial defense of early-laid eggs to protect them from the high risk of infection incurred before the onset of incubation. Among entire clutches, females may invest more resources in young sired by more attractive males because they have higher reproductive value. We tested these hypotheses by quantifying antimicrobial protein distribution within and among clutches in blue tit eggs. Contrary to our hypothesis, clutches showed no differential deposition of lysozyme or avidin within clutches, but eggs laid in the middle of the sequence had higher concentrations of ovotransferrin than eggs in the beginning and end. Consistent with our second hypothesis, we found that females produced eggs with higher concentrations of lysozyme (although not ovotransferrin or avidin) when mated to more attractive (more UV-reflective) males. Furthermore, females mated to polygynous males deposited less lysozyme than those mated to monogamous males. These data suggest that allocation of lysozyme at the clutch level may be a maternal effect mediated by male qualities.  相似文献   
229.
Lake Taihu is the third largest freshwater lake in China. It serves many social, economic, and ecological purposes in the drainage basin. Unfortunately, the water has been heavily polluted due to rapid industrialization and urbanization during the last two decades. Notwithstanding great efforts made so far to improve the water quality, the environmental situation is still far from being optimistic. The basin and the lake are facing a range of severe environmental challenges: rapid socio-economic development continues to place great pressures on the environment, current pollution control projects have many problems from the viewpoint of effectiveness and efficiency of their implementations, and the non-point sources of pollution such as agricultural fields, for which control is more difficult than for industrial point sources, have become the main contributors to serious eutrophication of the lake. Considering the characteristics of the environmental challenges and problems confronting the basin and the lake, we focus on integrated environmental management (IEM) as a promising and effective approach to overcome these predicaments. Current practices and problems of environmental management in the basin are examined, and potential future developments are discussed. Three aspects of the IEM are emphasized: institutional cooperation, public participation, and internalization of environmental externalities. We think these are the most critical for not only the basin but also for the whole of China to achieve a sustainable society.  相似文献   
230.
Russian Journal of Ecology - Methods of geometric morphometrics have been used to assess chronographic variation of morphofunctional traits in the same cenopopulations of the bank vole...  相似文献   
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