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The aim of present study was to improve compost quality as well as to achieve an optimum C/N ratio in compost, reduction in heavy metal content and increased water‐holding capacity of composting piles in arid areas. Four windrow compost piles were prepared by mixing sawdust at various dosages with municipal solid waste (MSW). The sawdust was mixed with MSW at 0% (MSW0), 16% (MSW16), 32% (MSW32), and 70% (MSW70) on dry weight basis. The compost piles were monitored daily by recording the temperature, while, weekly measurement was done on C/N ratio, moisture, pH, and electrical conductivity (EC). The addition of 16% sawdust increased the initial C/N to the optimum level and decreased N loss during the composting process. The MSW16 and MSW32 exhibited better temperature dynamics and their composting period seemed to be shorter than that of MSW0 and MSW70. Moreover, addition of sawdust caused lowering of moisture loss from the composting piles. Sawdust admixtures also produced lowering of pH and EC values and led to lower heavy metal content in final products. The quality of the final compost makes it possible to propose the use of this experimental procedure for building up a novel mass reduction of the initial composted waste mixtures. 相似文献
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M. Malakootian Ph.D. N. Yousefi A. Fatehizadeh 《International Journal of Environmental Science and Technology》2011,8(1):107-114
Water supply for consumption is one of the crucial objectives of water supply systems. Using of excessive fertilizer is a main source of nitrate content in water. The high amounts of nitrate in water have a determinable effect on the environment which must be removed due to drinking and industrial water standards. The purpose of this study is nitrate removal from aqueous solution by Electrocoagulation process. The applied pilot was comprised of a reservoir, electrode and power supply. In this study pH, electrical potential difference, nitrate initial concentration, total dissolved solid, kind of electrode, electrode connection methods and number of electrode were studied. Moreover, obtained optimum conditions were tested on Kerman water. The results showed that the electrocoagulation process can reach nitrate to less than standard limit. pH, electrical potential difference, total dissolved solids and number of electrodes have direct effect and initial concentration of nitrate has reverse effect on nitrate removal. This study also showed that under optimum condition, nitrate removal from Kerman water distribution system was 89.7 %. According to the results, Electrocoagulation process is suggested as an effective technique in nitrate removal. 相似文献
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The prediction of production rate in ornamental stones sawing is very important in cost estimation and process planning of the rock sawing plants. The main aim of this paper is finding a mathematical correlation between production rate and rock brittleness indexes. The utilized data have been collected from several stone factories in Iran. Seventeen different granite and carbonate rocks have been experienced sawing conditions with large-diameter circular saws. The laboratory tests such as uniaxial compressive strength and tensile strength, were carried out on the rock samples which were collected from these factories. The ratio of compressive strength to tensile strength (B 1), the ratio of compressive strength minus tensile strength to compressive strength plus tensile strength (B 2), and the area under the line of compressive strength and the line of tensile strength (B 3) were used as brittleness indexes in this study. Then, the relationships between these brittleness indexes and production rate were investigated by using a regression analysis. The results show that, there is not a good relationship between the production rate and B 1 and B 2. However, the production rate correlates with B 3 very well. Therefore, there is a reliable prediction for ornamental stones production based on B 3 as a brittleness indexes. 相似文献
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Mohammadmahdi Rezaei Yousefi Babak Salehi Kasmaei Abdolhossein Vahabie Caro Lucas Babak Nadjar Araabi 《Solar physics》2009,258(2):297-318
Various phenomena with solar origin and their mutual dependence must be studied in order to predict behaviors in solar – terrestrial
system. Linear statistical methods prevalent in analyzing natural systems may not be able to detect nonlinear dependencies
among solar and geomagnetic processes. When relations, whether linear or nonlinear, between indices and their changes over
time are revealed, better predictions can be made through appropriate modeling techniques. Selection of nonredundant input
variables to build suitable models for prediction of solar and geomagnetic activity is of utmost importance. Mutual information
is a tool that is capable of capturing all dependencies for detecting nonlinear relations and selecting the best subset of
input variables by means of an applicable algorithm that maximizes information about the output and minimizes the shared information
between inputs. High generalization power and improved interpretability of the selected inputs are the consequences of this
analysis. 相似文献
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Abbas Afshar Farzaneh Feizi Ameneh Yousefi Moghadam Motahareh Saadatpour 《Environmental Earth Sciences》2017,76(23):803
Intentional and/or accidental volatile organic compound (VOC) spill into water bodies may lead to severe contamination and health problems in water infrastructures. The importance and widespread use of petroleum products and the threats posed by these products on surface water resources in Iran necessitates the access to numerical hydrodynamic and water quality simulation models with appropriate capabilities. Simulation the fate and transport of VOC in both flowing and standing water bodies is a fairly complex problem. In this research, CE-QUAL-W2 model is modified to simulate the fate and transport of VOC [i.e., Methyl tert-butyl ether (MTBE), benzene] in standing and flowing water bodies. The performance of the modified CE-QUAL-W2 model is evaluated in a MTBE pollution spill at Khalife-Tarkhan river along the headwaters of Gheshlagh reservoir, Kordestan, Iran. The results show the modified CE-QUAL-W2 model’s capability to depict the spatial and temporal variation of MTBE in comparison with recorded data from MTBE spill event of Gheshlagh reservoir. Based on the simulation results of modified CE-QUAL-W2 model, reservoir cleanup time in different meteorological and hydrological scenarios is evaluated. The results show Gheshlagh reservoir cleanup time reduced in scenarios that included air temperature reduction, wind speed increasing, and high inflow condition. 相似文献
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R. Bagheri S. Mehregan A. Yousefi E. Mirrezaei 《International Journal of Environmental Science and Technology》2017,14(11):2443-2450
In this work, accumulation of cosmogenic radionuclide 7Be in seven species of lichens was determined using HPGe detectors in autumn season. Ramsar city which is located in the north of Iran as one of the high-level natural radiation areas in the world was considered. Lichen species represented good potential in accumulation of 7Be radionuclide. The foliose species of Xanthoria parietina with the highest activity concentration value of 112.8 ± 1.8 Bq kg?1 was introduced as bioindicator for accumulation of 7Be radionuclide. Cladonia rangiformis species has got minimum concentration of 64.5 ± 0.8 Bq kg?1. Also from thallus morphology viewpoint, results showed that 7Be accumulation in foliose species is higher than in fruticose and crustose lichens species. Also there was relatively large positive correlation between 7Be and 226Ra activity concentrations in lichens species. 相似文献
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Mahyar Yousefi 《Natural Resources Research》2017,26(4):429-441
In this paper, a pixel-based mapping of geochemical anomalies is proposed to avoid estimation errors resulting from using interpolation methods in the modeling of anomalies. The pixel-based method is a discrete field modeling of geochemical landscapes for mapping lithogeochemical anomalies. In this method, the influence area of each composite rock sample is the whole area covered by a pixel where the materials of the sample were taken from. In addition to the pixel-based method, because delineation of mineral exploration target areas using geochemical data is a challenging task, the application of metal zoning concept is demonstrated for vectoring into porphyry mineralization systems. In this regard, different geochemical signatures of the deposit-type sought were mapped in a model. Application of the proposed pixel-based method and the metal zoning concept is a powerful tool for targeting areas with potential for porphyry copper deposits. 相似文献
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Mohammady Majid Pourghasemi Hamid Reza Yousefi Saleh Dastres Emran Edalat Mohsen Pouyan Soheila Eskandari Saeedeh 《Natural Resources Research》2021,30(6):4861-4884
Natural Resources Research - Habitat suitability modeling and mapping are important aspects of long-term strategies for sustaining plant ecosystems. In this study, seven state-of-the-art machine... 相似文献