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51.
Benzene removal evaluated using Fe304 nano continuous condition. A 44 initial benzene concentration, from aqueous solutions was magnetic particles (NM) in factorial design including NM dose, contact time and pH was investigated in 16 experiments (Taguchi OA design). The results indicated that all factors were significant and the optimum condition was: pH 8, NM dose of 2000 mg.L-1, benzene concentrations of 100 mg.L-1 and contact time of 14min. The maximum benzene uptake and distribution ratio in the optimum situation were 49.4mg.g-1 and 38.4L.g-1, respectively. The nano particles were shown to capture 98.7% of the benzene in optimum batch condition and 94.5% in continuous condition. The isotherm data proved that the Bmnauer-Emmett-Teller model fit more closely and produced an isotherm constant (b) less than one, indicating favorable adsorption. Regeneration studies verified that the benzene adsorbed by the NM could be easily desorbed by temperature, and thereby, NM can be employed repeatedly in water and wastewater management.  相似文献   
52.
Understanding communicational behavior of rangelands’ stakeholders is fundamental for effective development of rangeland management plans. This study aimed to understand differences between stakeholders’ relations among various actors involved in rangeland management using social network analysis (SNA). A survey was conducted on 334 stakeholders (89 extension agents, 110 researchers and 135 executive agents) in the Tehran province, Iran. Results showed that all the three groups of stakeholders are interested in making contact mainly within their own group. Furthermore, while the executive agents have shared the strongest technical and friendship relations with the two other groups, the extension agents established the strongest administrative interactions. The researchers, however, made a poor link especially with the extension agents. The study concluded that SNA could be an efficient tool to assess communicational behavior in rangeland management.  相似文献   
53.
In this study, the volume and the cash value of water loss, and reduction of water loss as a result of enforcement action during 2011–2013 in the drinking water network of villages in Kermanshah Province, Iran, have been investigated. Date collected by referring to the different parts of rural water and waste water company of Kermanshah Province and checklist were completed. The study showed the volume of produced water and sold water has increased and the water loss percentage has decreased. High cost of water production compared to revenue of sold water and water loss resulted in significant detriments in terms of the water production costs. Water loss level decreased from 33% to 30% as result of measures taken to reduce water loss but, it is still 15% higher than the world average level. Also the reduction in number of water resources and increase in the number and volume of reservoirs indicates a lack of water and a growing need. As result of high water loss, waste of costs in the contrast of water production cost and also because physical water loss accounts for most of the water loss of villages, necessary measures can be effective in reducing loss and have economic justification.  相似文献   
54.
This article explains that the nature of commodity price determination and the characteristics of the link between commodity prices and prices of manufactured goods are such that they have an inflationary and recessionary impact on the world economy. Subsequently, it argues that International Commodity Price Agreements (ICAs) and the Common Fund are not only in the interest of developing countries but are also in the vital interest of developed countries. They assist in stabilizing economic activities and sustaining recovery at a higher rate of growth of output and employment in these countries. Nevertheless, to be effective for these purposes, ICAs should cover a wide range of commodities and adequate financial resources should be available to the First Account of the Common Fund.  相似文献   
55.
Environment, Development and Sustainability - Water resources allocation policies can create cooperation or tension among different stakeholders in a large basin. Thus, integrated water resources...  相似文献   
56.
Environmental Science and Pollution Research - The possibility of using different densities of cherry tomato as a bio-filter in a simple media-based aquaponic system to recycle nutrients from pearl...  相似文献   
57.
Environmental Science and Pollution Research - In the developing world, rapid urbanization and industrialization produces an enormous volume of wastes daily. This study was aimed to explore the...  相似文献   
58.
Ammonia-oxidizing bacteria and phenol-degrading yeast were isolated in order to study the synergism effects of phenol-degrading yeast and ammonia-oxidizing bacteria for enhancing the nitrification in coke wastewater from the Isfahan Steel Company. The influent and effluent samples with approximately 600-1200 mg L(-1) ammonium and 550-2350 mg L(-1) phenol were collected aseptically in sterile flasks. The biodegradation of phenol and nitrification were studied with different treatments. The results showed that addition of Na2CO3 and autotrophic bacteria to wastewater increased the ammonium removal by 100%. Furthermore, the synergism effects of phenol-degrader yeast and autotrophic bacteria reduced the time for ammonium removal.  相似文献   
59.
Environmental Science and Pollution Research - There is ambiguity about the airborne transmission of the SARS-CoV-2. While a distance of 6 feet is considered a safe physical distance, new findings...  相似文献   
60.
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