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261.
In this study, photocatalytic (photo-Fenton and H2O2/UV) and dark Fenton processes were used to remove ethylenethiourea (ETU) from water. The experiments were conducted in a photo-reactor with an 80 W mercury vapor lamp. The mineralization of ETU was determined by total organic carbon analysis, and ETU degradation was qualitatively monitored by the reduction of UV absorbance at 232 nm. A higher mineralization efficiency was obtained by using the photo-peroxidation process (UV/H2O2). Approximately 77% of ETU was mineralized within 120 min of the reaction using [H2O2]0 = 400 mg L?1. The photo-Fenton process mineralized 70% of the ETU with [H2O2]0 = 800 mg L?1 and [Fe2+] = 400 mg L?1, and there is evidence that hydrogen peroxide was the limiting reagent in the reaction because it was rapidly consumed. Moreover, increasing the concentration of H2O2 from 800 mg L?1 to 1200 mg L?1 did not enhance the degradation of ETU. Kinetics studies revealed that the pseudo-second-order model best fit the experimental conditions. The k values for the UV/H2O2 and photo-Fenton processes were determined to be 6.2 × 10?4 mg L?1 min?1 and 7.7 × 10?4 mg L?1 min?1, respectively. The mineralization of ETU in the absence of hydrogen peroxide has led to the conclusion that ETU transformation products are susceptible to photolysis by UV light. These are promising results for further research. The processes that were investigated can be used to remove pesticide metabolites from drinking water sources and wastewater in developing countries.  相似文献   
262.
农村小型生活污水处理技术研究进展   总被引:3,自引:0,他引:3  
针对农村的实际情况,寻找高效低耗的农村生活污水处理技术是很有实际意义的。本文主要从活性污泥法、生物膜法、人工湿地和组合工艺这几方面介绍了农村小型生活污水的处理现状,介绍了近几年来国内外的一些农村小型生活污水处理的研究发展情况。采用生物生态组合工艺,操作管理简单,投资和运行费用较低,适宜在农村小型生活污水处理中应用。  相似文献   
263.
An intense waste management (WM) planning activity is currently undergoing in England to build the infrastructure necessary to treat residual wastes, increase recycling levels and the recovery of energy from waste. From the analyses of local WM strategic and planning documents we have identified the emerging of three different energy recovery strategies: established combustion of residual waste; pre-treatment of residual waste and energy recovery from Solid Recovered Fuel in a dedicated plant, usually assumed to be a gasifier; pre-treatment of residual waste and reliance on the market to accept the ‘fuel from waste’ so produced. Each energy recovery strategy will result in a different solution in terms of the technology selected; moreover, on the basis of the favoured solution, the total number, scale and location of thermal treatment plants built in England will dramatically change. To support the evaluation and comparison of these three WM strategy in terms of global environmental impacts, energy recovery possibilities and performance with respect to changing ‘fuel from waste’ market conditions, the LCA comparison of eight alternative WM scenarios for a real case study dealing with a large flow of municipal wastes was performed with the modelling tool WRATE. The large flow of waste modelled allowed to formulate and assess realistic alternative WM scenarios and to design infrastructural systems which are likely to correspond to those submitted for approval to the local authorities. The results show that all alternative scenarios contribute to saving abiotic resources and reducing global warming potential. Particularly relevant to the current English debate, the performance of a scenario was shown to depend not from the thermal treatment technology but from a combination of parameters, among which most relevant are the efficiency of energy recovery processes (both electricity and heat) and the calorific value of residual waste and pre-treated material. The contribution and relative importance of recycling and treatment/recovery processes change with the impact category. The lack of reprocessing plants in the area of the case study has shown the relevance of transport distances for recyclate material in reducing the efficiency of a WM system. Highly relevant to the current English WM infrastructural debate, these results for the first time highlight the risk of a significant reduction in the energy that could be recovered by local WM strategies relying only on the market to dispose of the ‘fuel from waste’ in a non dedicated plant in the case that the SRF had to be sent to landfill for lack of treatment capacity.  相似文献   
264.
城镇化的发展使不透水面积不断增加,往往导致地区的水文过程发生较为明显的改变。以太湖上游西苕溪流域内的安吉城镇化实验小区为例,在对研究流域50多a长系列水文气象资料和区域城镇化特征作较详细分析的基础上,结合2005~2008年短时间尺度降雨径流观测实验,通过雨量、水位以及下垫面等数据分析,选用Storm Water Management Model这一暴雨洪水管理模型对该地区的典型洪水过程进行了模拟,对其降雨径流规律进行了分析。结果表明:该模型对该区域的模拟效果较好,误差较小,可以用于该城镇化地区的降雨径流过程模拟和洪水规律定量分析;分析该实验小区降雨径流过程可知,城镇化使该地区洪水上涨过程明显加快,6场典型洪水的峰型系数均值为305,洪峰流量增大而滞时缩短,较快的汇流速度使该地区的防洪压力较大。实验观测方法及模拟分析成果将有助于对太湖地区小流域城镇洪水过程特征与规律的认识,对我国东部城镇地区的防洪、规划与管理也具有重要的借鉴意义  相似文献   
265.
Deepening understanding of public responses to large-scale renewable energy projects is of academic and practical importance, given policies to lessen fossil fuel use in many countries. Although the NIMBY (Not In My Back Yard) concept is commonly used to explain public opposition, the concept has been extensively critiqued. This study applies an alternative approach based upon the notion of disruption to place attachment, and the theory of social representations, with a focus upon the symbolic meanings associated with a proposed project and the places affected by it. Empirical data is provided from a case study of a proposed 750 MW offshore wind farm in North Wales, using group discussions and questionnaires distributed to local residents in two coastal towns (n = 488). Results indicate significant differences between each town's residents in their responses to the project, and how opposition arises from nature/industry symbolic contradictions: between a place represented in terms of scenic beauty that provides a restorative environment for residents and visitors, and a wind farm that will industrialise the area and ‘fence’ in the bay. In one of the towns, the data suggests that contradiction between project and place was experienced as a threat to identity for those with strong place attachment, leading to negative attitudes and oppositional behaviour. Levels of trust in key actors moderated the relation between place attachment and negative attitudes to the wind farm. The results provide further evidence of the role of place attachment in shaping so-called ‘NIMBY’ responses to development proposals, and challenge the assumption that offshore wind farms will prove less controversial than those onshore.  相似文献   
266.
Recent research on the effects of personal threat suggests that perceived threat might enhance pro-environmental behavior when pro-environmental norms are in focus. In three experiments we found support for the latter assumption, showing that mortality salience and salience of pro-environmental norms interacted in predicting pro-environmental attitudes and information search (Study 1), sustainable behavior in a forest management game (Study 2), as well as pro-environmental intentions and behavior (Study 3). Specifically, mortality salience increased pro-environmental conduct only when pro-environmental norms were salient. Moreover, norm salience only had an effect on pro-environmental attitudes and behavior when the threat of personal mortality was salient. We discuss the implications of these results for both terror management theory and the promotion of pro-environmental behaviors.  相似文献   
267.
Lindehoff, Elin, Edna Granéli, and Patricia M. Glibert, 2010. Influence of Prey and Nutritional Status on the Rate of Nitrogen Uptake by Prymnesium parvum (Haptophyte). Journal of the American Water Resources Association (JAWRA) 46(1):121-132. DOI: 10.1111/j.1752-1688.2009.00396.x Abstract: We studied how the specific nitrogen (N) uptake rates of nitrate (NO3), urea, and the amino acids, glutamic acid and glycine, by Prymnesium parvum were affected by (1) the change from N-deficient status to N-sufficient status of the P. parvum cells, (2) presence of prey from a natural Baltic Sea plankton community, and (3) the composition of prey as affected by additions of terrestrial originated dissolved organic matter (DOM) or inorganic nutrients. Nitrogen-deficient P. parvum (16 μM NO3 and 4 μM PO4, molar N:P ratio of 4:1) were mixed with a natural Baltic plankton community and given PO43− and (1) NO3 (control) or (2) high molecular weight DOM, >1 kDa concentrated from sewage effluent (+DOM), in a molar N:P ratio of 9-10:1. With additions of 15N-enriched substrates, rates of N uptake from NO3, urea, and the amino acids glycine and glutamic acid were measured every 24 h for 72 h. Initial N-deficient P. parvum were highly toxic (3.7 ± 0.9 × 10−4 mg Sap equiv/cell) and toxic allelochemicals were released into the medium causing the natural plankton community to lyse. Rates of N uptake differed between the “control” and the “+DOM” treatments over time; total (sum of the N substrates measured) absolute uptake rates (ρcell, fmol N/cell/h) at ambient culture conditions were significantly higher (ANOVA, p < 0.05) in the more toxic “control” treatments compared with the “+DOM” treatments after 48 h. In the “control” treatment, the total ρcell increased significantly (ANOVA, p < 0.01) from time 0 to 48 h, while in the “+DOM” treatment there was no significant increase. Released organic nutrients from the lysed plankton cells may have increased uptake rates of amino acids and urea by P. parvum. All uptake rates declined in all treatments by 72 h. Total dissolved N uptake rates at ambient culture conditions were estimated to make up about 10% of the N P. parvum are potentially capable of ingesting from particulate prey.  相似文献   
268.
The imperative to further constrain extractive uses of natural resources will strengthen as resources degrade through over-use or exposure to climate changes. Here, we explore an approach to increase the support for marine conservation among coral reef fishers. We explore the proposition that resource dependency in the Egyptian Red Sea can act as a barrier to conservation. We administered face-to-face surveys to 49% of the fishing industry to: (i) identify the level of compliance to the local marine protected area (MPA), (ii) assess the level of dependency on marine resources in the region and (iii) examine the relationship between resource dependency and conservation attitudes. Only 11.4% of fishers were aware of the MPA. Fishers were mostly limited in their social flexibility and livelihood options. Results suggest that resource dependency is highly and negatively correlated with conservation attitudes suggesting that management efforts need to seriously focus on reducing dependency if conservation goals are to be met.  相似文献   
269.
Is there a place for social capital in the psychology of health and place?   总被引:1,自引:1,他引:0  
The field of environmental psychology is primely placed to further understanding of the way in which social capital influences or is influenced by the context and characteristics of neighbourhood environments, but has been one of the quieter voices in the cacophony of social capital discourse over the last decade. While there is increasing research interest in area and neighbourhood variations in social capital, the mechanisms and causal pathways through which physical environments, social capital and health may be related are not yet clear. More refined unpacking of the relationship between social capital and neighbourhood design, features and settings is required to identify practical intervention points for preserving, fostering and harnessing social capital within communities. Through a review of literature, this paper explores whether there is a place for social capital in the psychology of place and considers the contribution that environmental psychology and related disciplines could make to future social capital research and applications.  相似文献   
270.
This study incorporated identity constructs into the theory of planned behaviour (TPB) to investigate intentions to engage in environmental activism. First year students and participants of a students of sustainability conference (n=169) were administered a questionnaire survey that measured standard TPB constructs as well as environmental group membership and self-identity as an environmental activist. Consistent with predictions, environmental group membership and self-identity were positive predictors of intentions. Thus, greater involvement in environmental groups and a stronger sense of the self as an environmental activist were associated with stronger intentions to engage in environmental activism. There was also evidence that self-identity was a stronger predictor of intentions for participants with low rather than high environmental group membership. In accordance with the standard TPB model, participants with more positive attitudes toward and a greater sense of normative support for environmental activism also had greater intentions to engage in the behaviour. The implications for groups seeking to harness support for activities to protect the environment are discussed.  相似文献   
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