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71.
Green spaces considered natural remnants in urban environments play a key role in promoting environmental quality and forming a sustainable city. Nowadays, development of urban spaces has taken a hasty growth. In the meanwhile, the natural green spaces are severely damaged. The current study aims at investigating the trend of changes in green space of Tabriz City, the second large industrial city in Iran, on the basis of landscape ecology principles. In order to prepare the land-cover maps, Landsat TM and IRS LISS-III of the years 1989 and 2006 were applied. Alongside, landscape percentage metrics, the largest patch index, number of patches, patch density, edge density, total edge, class area and landscape shape index were also used to analyse the changes. Metric analysis of the landscape within the studied years revealed that a large part of the region has enjoyed a rapid growth (equivalent to 64.5 %) in constructions. As the obtained results showed, the smallest landscape percentage (3.9 %) in the study area is belonged to the municipal green space, while the largest landscape percentage (66 %) is allocated to the barren land. This shows that the constructions have not balanced with creation of new green spaces, and the lack of green space per capita continues to be felt.  相似文献   
72.
The influence of the various preparation methods of Cu-SAPO-34 nanocatalysts on the selective catalytic reduction of NO with NH3 under excess oxygen was studied. Cu-SAPO-34 nanocatalysts were prepared by using four techniques: conventional impregnation (IM), ultrasound-enhanced impregnation (UIM), conventional deposition precipitation (DP) using NaOH and homogeneous deposition precipitation (HDP) using urea. These catalysts were characterized in detail by various techniques such as N2-sorption, XRD, TEM, H2-TPR, NH3-TPD and XPS to understand the catalyst structure, the nature and the dispersed state of the copper species, and the acid sites for NH3 adsorption. All of the nanocatalysts showed high activities for NO removal. However, the activities were different and followed the sequence of Cu-SAPO-34 (UIM) > Cu-SAPO-34 (HDP) > Cu-SAPO-34 (IM) > Cu-SAPO-34 (DP). Based on the obtained results, it was concluded that the NO conversion on Cu-SAPO-34 nanocatalysts was mainly related to the high reducibility of the isolated Cu2 + ions and CuO species, the number of the acid sites and the dispersion of CuO species on SAPO-34.  相似文献   
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This research studied the application of fish bone as a low-cost adsorbent for the removal of two basic dyes (C.I. Basic Blue 41 and C.I. Basic Yellow 28) from textile wastewaters. The surface morphology and functional groups of the fish bone was studied by scanning electron microscopy and Fourier transform infrared, respectively. The experiments were designed in two methods: classical method and response surface methodology (RSM). The effect of operating parameters including pH, initial dye concentration, adsorbent dosage, and inorganic salts was investigated by both methods. The optimum conditions to satisfy 75 % of dye removal for both dyes were predicted by RSM method and the results were very close to the experimental values. So, it was concluded that the fish bone can be used as a low-cost adsorbent for dye removal from effluents.  相似文献   
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Environment, Development and Sustainability - The tourism sectors consume a high amount of electrical power, which in most cases is supplied by the electrical grid and diesel generator. As a...  相似文献   
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Environmental Science and Pollution Research - In this study, simultaneous removal of an organic matter (diazinon, DIZ) and an inorganic substance (chromium, Cr) was used. Breaking down of organic...  相似文献   
79.
Root and shoot lead concentrations and the impact of chelating agents on these were investigated in two populations of the novel metallophyte Matthiola flavida. Plants were exposed in hydroponics to Pb(NO3)2, supplied alone, or in combination with citric acid, or EDDS. When supplied at concentrations expected to bind about 95% of the Pb in a solution containing 1-μM Pb (1000 μM citrate or 3.1 μM EDDS, respectively), the root and shoot Pb concentrations were dramatically lowered, in comparison with a 1-μM free ionic Pb control exposure. A 1-mM EDDS + 1-μM Pb treatment decreased the plants’ Pb concentrations further, even to undetectable levels in one population. At 100 μM Pb in a 1-mM EDDS-amended solution the Pb concentration increased strongly in shoots, but barely in roots, in comparison with the 1-μM Pb + 1-mM EDDS treatment, without causing toxicity symptoms. Further increments of the Pb concentration in the 1-mM EDDS-amended solution, i.e. to 800 and 990 μM, caused Pb hyperaccumulation, both in roots and in shoots, associated with a complete arrest of root growth and foliar necrosis. M. flavida seemed to be devoid of constitutive mechanisms for uptake of Pb-citrate or Pb-EDDS complexes. Hyperaccumulation of Pb-EDDS occurred only at high exposure levels. Pb-EDDS was toxic, but is much less so than free Pb. Free EDDS did not seem to be toxic at the concentrations tested.  相似文献   
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Prediction of groundwater depth and elevation is important in quantitative water management especially in arid areas. There are several basins in southwest of Iran, in Zagross Mountain, in which the water wells are distributed along a narrow elliptic ring band around the region. To find the most applicable interpolation method, both of the groundwater depth and elevation are predicted by different kriging methods. It is found that the groundwater elevation and depth can be predicted by different methods. Furthermore, it is found that the methods in which the trend is eliminated predicted the groundwater elevation and depth in central part of the region is with less standard error. Furthermore, the methods with no trend elimination, predicted the groundwater depths with less error near the water wells. Dividing the area to hydro-geologically homogeneous sub-areas improved the interpolation precision.  相似文献   
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