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Monitoring of SO2 column concentration over Iran using satellite-based observations during 2005-2016
2019
Salmabadi, H. | Saeedi, M.
For the first time, sulfur dioxide concentration was monitored between 2005 and 2016 over Iran which is among the countries with a high SO2 emission rate in the world. To that end, SO2 column concentration at Planetary Boundary Layer (PBL) from Ozone Monitoring Instrument (OMI) was analyzed. OMI is a sensor onboard the Aura satellite which can measure daily SO2 concentration on the global scale. From OMI maps, 19 notable SO2 hotspots were detected over Iran. The results indicate that the most elevated level of SO2 among these 19 hotspots belong to Khark Island and Asaluye in Bushehr province, southwest of Iran. Annual trend analysis shows that SO2 concentration has been slightly augmented during 2005-2016 over this country. Distribution analysis of SO2 concentration over Iran showed that the most polluted provinces are Bushehr, Khuzestan and Ilam lied in the southwest of Iran. On the contrary, the lowest level of SO2 has observed over northwest of Iran at West and East Azerbaijan and Ardabil provinces. The correlation coefficient between total energy production in Iran and SO2 concentration from 2005 to 2016 is as high as ~0.7. Hence, it can be derived that energy production, most notably production of crude oil, plays a pivotal role in SO2 concentration over Iran.
اظهر المزيد [+] اقل [-]Stabilization of Filter Cake and its Leaching Behaviour: A Case Study with Cementitious and Soluble Phosphate Additives
2019
Shirdam, R. | Nourigohar, A. | Mohamadi, S.
Filter cake is one of the main waste products of zinc processing industries and it contains a high amount of toxic heavy metals. In this research in order to reduce heavy metals leachability in filter cake, Portland cement, natural pozzolan, diammonium phosphate (DAP), triple superphosphate (TSP), lime, zinc oxide and ground granulated blast furnace slag (GGBFS) have been used. This research’s results suggest that even though leachability of lead in the filter cake is quite low, it should be noted that limestone doubles the solubility level of Pb due to the mineralogical nature of the waste, by converting its sulphate form (PbSO4) to its carbonate form (PbCO3), which is more soluble. TSP was the only additive capable of reducing the leachability of metal elements in the filter cake as well as stabilizing the amounts of Pb and Cd in TCLP extracts within the limit. Although all additives were able to reduce Cd leachability, TSP and ZnO had the most remarkable efficiency. According to XRD results, the main factor in lead stabilization using TSP was a reduction in the amount of PbSO4 (with high Ksp) and an increase in PbS (with low Ksp), which ultimately reduced lead leachability. The Pozzolan which was used for the first time as a stabilizer demonstrated a good performance in reducing the leachability of Cd, Ni and Cu. In addition, due to the pseudo-cementitious properties of Pozzolan, it can reduce leachability of metal elements, along with other additives such as cement, by increasing the solidification efficiency.
اظهر المزيد [+] اقل [-]Evaluation of Ecological Vulnerability in Chelgard Mountainous Landscape
2019
Darabi, H. | Islami Farsani, S. | Irani Behbahani, H.
Although complexity and vulnerability assessment of mountain landscapes is increasingly taken into consideration, less attention is paid to ecophronesis-based solutions so as to reduce the fragile ecosystem vulnerability. The main propose of this study is to provide an insight of mountain complex landscape vulnerability and propose ecophronesis-based solutions in strategic planning framework for reduction of vulnerability. The study has been carried out by following five steps in Chelgard Mountain landscapes (center of Iran): First, it determines the evaluation framework on basis of rapid literature review. Second, the vulnerability is assessed, using Analytic Hierarchy Process (AHP), in accordance with experts’ opinion. In the third step, the results provide a zoning map of vulnerability. Afterwards, the study suggests a strategic plan to manage the area environmentally and, finally, the solutions are proposed, based on ecophronesis, in order to not only solve the plight but also reduce the vulnerability. Results from the vulnerability assessment indicate that anthropogenic stressors intensify the vulnerability. While local ecological wisdom is shaped over time in the area, its application faces challenges as a result of rapid and immense socio-economic changes. It seems that sustainability of mountain ecosystem needs to regenerate social structures on basis of socio-ecological capital. Main characteristics of these adopted social structures include their balance with the ecosystem and adoption with new lifestyles.
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