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671.
Ali Azizi Amineh Ghorbani Bahram Malekmohammadi Hamid Reza Jafari 《Journal of Environmental Planning and Management》2017,60(10):1785-1808
Although mismanagement of groundwater resources has resulted in their destruction over centuries, climate change is speeding up this process more than ever. On the one hand, urgent action by government bodies is needed to address the challenge. On the other hand, a vast body of literature proves that bottom-up collective action, although requiring a longer time period, is a better solution to manage such resources. This research aims to address this dilemma. The groundwater resource in Ardabil plain in Iran, which has long been managed solely through government intervention, has been chosen as a case study to explore the opportunities and limitations of managing a critically endangered area from a common pool resource perspective. Our study suggests that managing Ardabil groundwater resources should be conducted on two scales. The bottom-up institutional agreements should take place at village scale while the government should stay in charge of the overall organization at plain scale. 相似文献
672.
Manel Haddar Ahmed Elloumi Ahmed Koubaa Chedly Bradai Sebastien Migneault Foued Elhalouani 《Journal of Polymers and the Environment》2017,25(3):617-627
Deinking paper sludge (DPS)/high density polyethylene (HDPE) composites with and without coupling agent (3 % of maleated polyethylene (MAPE)) were manufactured by twin-screw extrusion followed by injection molding with high percentages of DPS (0, 20, 30 and 40 %). The effects of DPS content and MAPE on the mechanical, thermal, and morphological properties of the DPS/HDPE composites were investigated. Increasing DPS content in composites increased the tensile and flexural modulus (E; MOE), tensile and flexural strength (Rm; MOR), while decreased elongation at break and Un-notched impact resistance due to a poor adhesion between the DPS and HDPE. The addition of DPS also improved the thermal stability and increased the composites crystallinity. High content of DPS (40 %) and 3 % MAPE achieved good interfacial adhesion between fibres of DPS and HDPE. Therefore, an increase is observed for Rm, MOR, ductility, and impact toughness. 相似文献
673.
Meor Othman Hamzah Ali Jamshidi Zulkurnain Shahadan 《Journal of Cleaner Production》2010,18(18):1859-1865
Warm-mix asphalt (WMA) has been gaining popularity in the asphalt industry primarily because of its ability to lower the energy required to blend asphalt mixes, which in turn results in less fuel consumption, slower aging of the asphalt binder and reduced emission of greenhouse gases. This paper evaluates the effects of different quantities of a WMA additive known as Sasobit® on the required heat energy and the amount of CO2 produced to increase the temperature of two aggregates from three sources and one binder from 25 °C to the point of mixing. The results showed that incorporating 1% Sasobit® can potentially reduce the required heat energy and amount of CO2 produced by 2.8% and 3.0%, respectively, for all aggregate types and sources investigated. The paper also presented design charts that enable energy policy makers and engineers to select the appropriate Sasobit® content to produce the most cost effective asphalt mixture with less environmental impact. The design charts show that 1.6% Sasobit® content is the most suitable proportion to be blended into the asphalt binder without compromising pavement resistance against fatigue failure. Two similar aggregates from different sources may exhibit similar specific gravities, but their specific heat capacities can vary widely. These differences have a significant effect on the required heat energy, asphalt production cost and the amount of emissions released into the environment. 相似文献
674.
675.
Heterospecific matings are generally assumed to be unconditionally disadvantageous due to reduced viability or fertility of
hybrid offspring. For female collared flycatchers (Ficedula albicollis) mated to male pied flycatchers (Ficedula hypoleuca), the cost of heterospecific pair formation is reduced due to high levels of conspecific extra-pair paternity and a male-biased
offspring sex ratio. In order to investigate whether these cost-reducing mechanisms are the result of female mating strategies,
rather than being a by-product of species incompatibilities, we manipulated the plumage of male collared flycatchers before
pair formation to make them resemble male pied flycatchers. Since species incompatibilities are absent in this design, any
systematic effect of manipulation on sex ratio or paternity would indicate a role of female mating strategy. Paternity was
determined by means of a likelihood approach that controls the errors made in assigning a chick to be ‘within-pair’ or ‘extra-pair’.
Neither the sex ratio nor the male share of paternity was affected by the manipulation in a systematic manner. We therefore
conclude that our experimental data provide no support for the suggestion that female behavioural strategies are markedly
adjusted in response to formation of mixed-species pairs.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
676.
677.
The alkaline conditions for extraction of natural dye from Henna leaves were optimized and the resulting extract was used to further optimize its dyeing conditions on cotton by exhaust method. Dyeings without any mordant were compared with those obtained with premordanting and postmordanting with alum and iron. It was found that dyeings produced with alkaline extracts of Henna leaves have better colour strength than the dye extracts obtained in distilled water. Furthermore, dyeings with alkaline extracts have moderate to good fastness properties and that mordanting did not result in any significant improvement in fastness properties. Finally, in comparative studies between synthetic and this natural dye, it was inferred that natural dye has good potential to act as co-partner with synthetic dye. 相似文献
678.
Ali Guney M. Ibrahim Poyraz Olgac Kangal Firat Burat 《Waste management (New York, N.Y.)》2013,33(9):1795-1799
Plastics have become the widely used materials because of their advantages, such as cheapness, endurance, lightness, and hygiene. However, they cause waste and soil pollution and they do not easily decompose. Many promising technologies are being investigated for separating mixed thermoplastics, but they are still uneconomical and unreliable. Depending on their surface characteristics, these plastics can be separated from each other by flotation method which is useful mineral processing technique with its low cost and simplicity.The main objective of this study is to investigate the flotation characteristics of PET and PVC and determine the effect of plasticizer reagents on efficient plastic separation. For that purpose, various parameters such as pH, plasticizer concentration, plasticizer type, conditioning temperature and thermal conditioning were investigated. As a result, PET particles were floated with 95.1% purity and 65.3% efficiency while PVC particles were obtained with 98.1% purity and 65.3% efficiency. 相似文献
679.
Mohammad Hossein Keshavarz Somayeh Moradi Ali Reza Madram Hamid Reza Pouretedal Karim Esmailpour Arash Shokrolahi 《Journal of Loss Prevention in the Process Industries》2013,26(4):650-659
This work presents a novel, reliable and simple method of estimating the flash point of various types of flammable amines, which are important for safety measures in industrial processes. Different amines include aliphatic amines such as primary, secondary, tertiary and cyclic amines as well as aromatic amines and hetero arenes containing nitrogen heteroatom. The proposed correlation is based on the contribution of some specific molecular moieties and functional groups, which can easily be used for any types of amines. Intermolecular forces are important in the new method, which are counted by two increasing and decreasing parameters. The root mean square (rms) deviation is 18 K for different classes of amines including 133 diverse compounds. The estimated flash points have been compared with one of the best available predictive methods, which gives much lower value of the rms deviation. 相似文献
680.
Ahmet Karaburun Ali Demirci I-Shian Suen 《Environmental monitoring and assessment》2010,166(1-4):267-277
This article reports findings of a study that examined the impacts of urban growth on forest cover in Istanbul between 1987 and 2007. Four Landsat images from 1987, 1990, 2000, and 2007 were classified with maximum likelihood supervised classification method by using ERDAS IMAGINE 9.1. Forest and urban areas were given highest importance in the classification, while other land-use characteristics, like agriculture and bare soil, were grouped into a third class as others. The study revealed that rapid increase in population and accompanying unplanned urban growth in Istanbul resulted in significant changes in land use after 1987. Urban areas have expanded 87.9% from 1987 to 2007, while forest areas declined 5.4% in the same period. One of the most significant results of the study was that total forest areas in Istanbul have increased 0.3% between 2000 and 2007. This suggests that progress has been made in Istanbul not only in having sustainable urban growth, but also in preserving, restoring, and even expanding forest areas, especially after the year 2000. 相似文献