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131.
In the present paper, the optimum design of a PV system used to operate a water pumping system was determined for Oman. The system design focused on the environmental conditions of Sohar city. The implementation and measurement of the designed system are presented to prove the effectiveness of the proposed system. The results show that the system can provide the required power at peak hours, leading to a substantial reduction in the sizing of the PV system. Consequently, the investment capital costs 2400 USD, and the cost of energy is equal to 0.309 USD/kWh. Furthermore, the results indicate that the system annual yield factor is 2024.66 kWh/kWp and that the capacity factor is 23.05 %, which is encouraging since the latter is typically 21 %. The system capital cost and the cost of energy are worth comparing to a diesel generator. A comparison is made between the proposed system and several others in the literature. The comparison indicated that the system cost of energy is promising.  相似文献   
132.
The occurrence of arsenic in drinking water and its detrimental effects have drawn much attention in recent years. Several studies have been conducted in the deltaic plains of River Ganga, NE part of the India, and in other countries, but no systematic study was conducted in South India on occurrence of arsenic in groundwater. The main aim of this study is to determine the level of arsenic in groundwater and to understand the relation with other geochemical parameters of groundwater in the south-eastern coastal aquifer at Kalpakkam region, India. This region is represented by three different lithologies, viz. charnockites, flood plain alluvium and marine alluvium. Twenty-nine representative samples of groundwater were collected and analysed for major ions, metals and isotopes such as 2H and 18O. In addition, geophysical method was also attempted to understand the subsurface condition. The spatial variation in arsenic (As) indicates that higher concentration was observed around the landfill sites and irrigated regions, which was supported by geochemical, statistical and isotopic inferences. The variation in the As with depth, lithology and sources has been clearly brought out. Though the values of As does not exceed the drinking water permissible limit (10 mg/l), it has reached a near permissible level of 8.7 ppb. Hence, it is essential to understand the geochemical behaviour of As for a proper future management of the water resource in the study area.  相似文献   
133.
Greening flood protection (GFP) is increasingly recognized as an adaptive and flexible approach to water management that is well suited to addressing uncertain futures associated with climate change. In the last decade, GFP knowledge and policies have developed rapidly, but implementation has been less successful and has run into numerous barriers. In this paper, we address the challenge of realizing green flood protection goals by specifically considering knowledge in the decision-making of a Dutch flood protection project in Lake Markermeer. In this project, an ecological knowledge arrangement and a traditional flood protection knowledge arrangement are compared and their interactions analysed. The analysis provides insight into the specific difficulties of implementing GFP measures and identifies ways to realize GFP goals. The primary challenge is twofold: First, a self-reinforcing cycle of knowledge production and decision-making in the flood protection domain inhibits the introduction of innovative and multifunctional approaches such as GFP; second, the distribution of power is severely unbalanced in terms of ecological enhancement and flood protection, favouring the latter. Implementation of GFP requires structural change and the integration of ecological and flood protection knowledge and policy. Potentially rewarding routes towards this integration are the exploration of shared interests in GFP and the creation of mutual dependency between knowledge arrangements. The case study and the insights it provides show that GFP is far from mainstream practice and that implementation requires serious effort and courage to break with historical practices.  相似文献   
134.
Due to increasing emphasis on sustainable practices, many organisations have attempted to leverage their supply chain performance towards balancing triple bottom line dimensions (economic, environmental and social perspectives). This paper, therefore, determines the priorities of sustainable supply chain management focusing on eco-design. Interpretive structural modelling (ISM) and Matriced’ Impacts Croise’s Multiplication Appliquée a UN Classement (MIMAC) are used to identify the hierarchical structure of the relationships among eco-design dimensions, and to analyse characteristics power of each dimension on supporting eco-design practices. The relationships and characteristics power of each dimension are used to determine indicators that are effective in enhancement of eco-design practice, evaluated through sustainable supply chain performance. Results indicate that product deployment is an important approach for improving eco-design practice towards sustainable supply chain management. This emphasises the purpose and impact of eco-design on sequential supply chain activities at deployment phase. Further research is required to make an overall assessment of eco-design practices across range of manufacturing industries, given the current research is based on inputs from a limited number of experts of selected organisations.  相似文献   
135.
Jonathan M. H. Green  Gemma R. Cranston  William J. Sutherland  Hannah R. Tranter  Sarah J. Bell  Tim G. Benton  Eva Blixt  Colm Bowe  Sarah Broadley  Andrew Brown  Chris Brown  Neil Burns  David Butler  Hannah Collins  Helen Crowley  Justin DeKoszmovszky  Les G. Firbank  Brett Fulford  Toby A. Gardner  Rosemary S. Hails  Sharla Halvorson  Michael Jack  Ben Kerrison  Lenny S. C. Koh  Steven C. Lang  Emily J. McKenzie  Pablo Monsivais  Timothy O’Riordan  Jeremy Osborn  Stephen Oswald  Emma Price Thomas  David Raffaelli  Belinda Reyers  Jagjit S. Srai  Bernardo B. N. Strassburg  David Webster  Ruth Welters  Gail Whiteman  James Wilsdon  Bhaskar Vira 《Sustainability Science》2017,12(2):319-331
Delivering access to sufficient food, energy and water resources to ensure human wellbeing is a major concern for governments worldwide. However, it is crucial to account for the ‘nexus’ of interactions between these natural resources and the consequent implications for human wellbeing. The private sector has a critical role in driving positive change towards more sustainable nexus management and could reap considerable benefits from collaboration with researchers to devise solutions to some of the foremost sustainability challenges of today. Yet opportunities are missed because the private sector is rarely involved in the formulation of deliverable research priorities. We convened senior research scientists and influential business leaders to collaboratively identify the top forty questions that, if answered, would best help companies understand and manage their food-energy-water-environment nexus dependencies and impacts. Codification of the top order nexus themes highlighted research priorities around development of pragmatic yet credible tools that allow businesses to incorporate nexus interactions into their decision-making; demonstration of the business case for more sustainable nexus management; identification of the most effective levers for behaviour change; and understanding incentives or circumstances that allow individuals and businesses to take a leadership stance. Greater investment in the complex but productive relations between the private sector and research community will create deeper and more meaningful collaboration and cooperation.  相似文献   
136.
The chemical composition of water conditioned by colonies ofMoina macrocopa and involved in the regulation of their life cycle was analyzed in comparison with water samples from natural water bodies. Dechlorinated tap water was used as the control medium. The results showed that metabolism of crustaceans leads to an increase in the concentrations of phosphorus and nitrogen in all forms, the appearance of protein and carbohydrate fractions, and changes in the composition of lipid fractions in the water conditioned by their colonies. The contents of all organic components are very low, which makes their identification difficult. Concentrations of substances identified in the conditioned water do not exceed those occurring in nature.  相似文献   
137.
The use of quantitative data for constructing prognostic maps of the dynamics of ecosystem degradation and restoration by nonlinear simulation methods is a topical field of landscape ecology. This method of dynamic cartography is based on fiberwise comparison of data on the state of Chernye Zemli (the Kalmyk Republic, Russia) in different years and the detailed analysis of the period on which the prognosis was based. For this purpose, materials of repeated aerial and satellite photography obtained during a long period (1954–1993) were used. Comparison of maps characterizing the dynamics of Chernye Zemli between 1958 and 1993 allows prognostic electronic maps for the next 10–15 years (with a five-year interval) to be drawn and land prognosis for the next 20–30 years (1998–2023) to be obtained. Deceased  相似文献   
138.
The data on the dynamics of population size and species composition of wasps from the families Pompilidae, Sphecidae, and Vespidae were obtained in the course of long-term studies carried out in successional pine forests of the Berezinskii Biosphere Reserve. The abundance and species diversity of wasps were significantly higher in a polewood forest (40 years) than in a young forest (20 years) and mature moss forest (70 years). In an overgrown ride in the moss pine forest, the composition of dominant wasp species remained relatively stable during the seven-year period of observations, although the number of species and their abundance varied significantly from year to year, depending on the weather.  相似文献   
139.
A coloured rain event originating from the Sahara Desert occurred on April 9, 2000 at Thessaloniki, Northern Greece (40 degrees 38'N, 22 degrees 58'E). The radioactive nuclides that were determined in a coloured rain dust sample were 137Cs of Chernobyl origin, 7Be of cosmogenic origin and 40K of terrestrial origin. Cesium-137 still remained 14 years after the Chernobyl accident, reaching 26.6 Bq kg-1 in the coloured rain dust.  相似文献   
140.
Radioactive contamination of wood and its products   总被引:1,自引:0,他引:1  
This paper presents research on radioactive contamination of the three most common kinds of wood in Croatia--beech, oak and fir as well as acorn. Gamma-spectrometric measurements carried out on the samples of bark and wood of beech, oak, fir and acorn have shown radioactivity contents ranging from 1.6 +/- 0.1 to 37.3 +/- 0.5 Bq/kg from deposited 137Cs, whose concentrations in the soil of Croatia have increased after the Chernobyl accident. Measurements have also shown the radioactivity originating from 40K and 214Bi, which are part of the natural composition of the soil. The distribution of the radionuclides in wood has been discussed, as well as the impact of radioactive contamination of wood by the artificial radionuclide 137Cs upon the forest ecosystem. According to the corresponding model, it has been calculated that a 10 h daily stay in a typical family house increases the annual radiation dose of the population, due to the deposited 137Cs in the structure or furniture, by 343 microSv.  相似文献   
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