Hamidreza Rudi
Shahrokh Nazmara; fatemeh eslami; mehdi salari; Alireza beheshti; Mohsen Yazdani avval
Abstract
Background & objective: People commonly spend, on average, 5-6% of their time in a day in enclosed vehicles. Smoking in vehicles with little volume can result in potential harmful effects on children and other passengers. This study aimed to evaluate the concentrations of suspended particles produced ...
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Background & objective: People commonly spend, on average, 5-6% of their time in a day in enclosed vehicles. Smoking in vehicles with little volume can result in potential harmful effects on children and other passengers. This study aimed to evaluate the concentrations of suspended particles produced from smoking and the exposer time of passengers to the produced smoke. Materials & Methods: This cross–sectional study was performed in Tehran, 2014. The exposure to cigarette smoke was measured using Grimm11-A device that had 16 entrances with different sizes from 0.3 to 20 µm. The studied vehicle was Pejo 405 , andwindows condition were as following: 1 back window open, 2 back windows open, 1 front window open, 2 front windows open, 2 front and 1 back windows open, 4 windows open and 4 windows close. SPSS 16 software was used to make statistical analysis ( one-way ANOVA (p<0/05)). Results: Numerical concentrations of particles in small size row (PM2.5) were several LOGs higher than larger sizes row. In addition, it was observed that exposure time to particles in small size row had significant difference with large size row. The maximum exposure concentrations with a p-value<0.05, and the maximum exposure time with a p-valueConclusion: According to the gained results, the largest portion of cigarette smoke particles in vehicles belonged to the PM2.5. Different conditions of windows in their opened and closed states can be effective on ventilation. So that the more numbers of windows are opened the greater ventilation will occure. Generally, because of the limit space of vehicles and high exposure concentrations, the enactment of cigarette smoking prohibition legislation seems to be necessary.
Ali akbar Mohammadi; Hossein Alidadi; Mohammad Bagher Delkhosh; Seyede Horriey Fallah; Abdoliman Amouei; Hosseinali Asgharnia; Vahid Taghavi manesh; Monireh Ghorbani
Abstract
Background and purpose: Exposure to the environmental noise originated from traffic is common in urban areas, and can lead to the adverse health effects. Present study aimed to determine average Sound Level Index (SLI) and noise pollution in overcrowded areas of Neyshabur, Iran. Materials and methods: ...
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Background and purpose: Exposure to the environmental noise originated from traffic is common in urban areas, and can lead to the adverse health effects. Present study aimed to determine average Sound Level Index (SLI) and noise pollution in overcrowded areas of Neyshabur, Iran. Materials and methods: This cross-sectional study was accomplished over three primary months of 2015 in Neyshabour city. Six stations in main and crowded parts of Neyshabour including Imam Khomeini, Enghelab Square, Khayyam Square, Azadi Square, Beasat crossroad and Attar Street were applied to measure the SLA in three time period of a day. The measurements were carried out using SVAN953 mean. Statistical analyses of the obtained data were performed by SPSS 18 software. Results: The achieved results revealed that the average SLI at the aforementioned stations were (100.06 ±5.16), (93.38 ± 5.15), (86.58 ± 4.96), (93.38 ± 5.15), (97.38 ± 4.15) and (96.90 ± 2.17) dB respectively. The maximum and minimum Equivalent sound levels were 125.4 and 80.2 dB at the Imam Khomeini station (as a commercial area) in the morning and Beasat station (as a residential area) in the evening correspondingly. Conclusion: In all stations, the measured sound pressure levels were higher than its permission limit for residential and commercial areas. Regarding the adverse health effects of noise pollution, it needs to perform required investigations to reveal the effective factors.
Mohammad Soleimani; kivan khalili; javad Behmanesh
Abstract
Introduction : More than three decades, hydrologists , using multivariate models to describe complex data modeling. While recently the importance of multivariate models have been proposed in hydrology.Indeed, the results of multivariate models can improve the results of description, modeling, and prediction ...
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Introduction : More than three decades, hydrologists , using multivariate models to describe complex data modeling. While recently the importance of multivariate models have been proposed in hydrology.Indeed, the results of multivariate models can improve the results of description, modeling, and prediction of different parameters by involving other influential factors. Methods: In this study, univariate models (ARMA) and auto-correlated multivariate models with simultaneous autoregressive moving average model (CARMA) were evaluated for modeling EC and TDS parameters of the Southern stations of Urmia Lake Basin. In order to employ CARMA models, annual flow rate timeseries, EC, TDS, SAR, and pH values measured across 3 hydrometric stations (Kotar- Balqchy- Gerdyaghob ) within 1992-2013 were used. Findings: The results of the qualitative parameters of the West River basin of Lake Urmia Showed that in the period under review the flow of the studied rivers in the south of Lake Urmia decrease And the EC and TDS values have experienced an increasing trend. EC and TDS values modeling results showed that the average error (RMSE) EC in modeling values equal to 16/60 mho / cm into the teaching and 13/26 mho / cm in the testing phase and for the TDS parameter values 19/84 and 12/71 in the testing phase is the phase of training. The estimated values of the calculation error and accuracy of the model is located entirely within the confidence interval. Conclusion: The results of multivariate modeling EC and TDS values showed that the involvement of the parameters listed in the model , modeling accuracy will be satisfactory.
Ayoub Khosravi Fard; Ghorban Vahabzadeh; Leila Gholami
Abstract
Background: Water is considered as a vital element in the life cycle. Therefore, water safety in drinking and agricultural fields is one of the communities’ necessities to protect health of humans and environment. Objective: The main objective of the present study was to evaluate and classify ...
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Background: Water is considered as a vital element in the life cycle. Therefore, water safety in drinking and agricultural fields is one of the communities’ necessities to protect health of humans and environment. Objective: The main objective of the present study was to evaluate and classify the water quality of Ghorbaghestan and Doab Merk Stations in Kermanshah Province owing to the importance of their drinking and agricultural uses as well as recent droughts in Kermanshah province and Gharasoo watershed resulting in discharge reduction of Gharasoo river. Material & Methods: The studied parameters of water chemical quality in this study were salts residual, acidity, electrical conductivity, bicarbonate, chloride, sulfate, magnesium, calcium, sodium, potassium, sodium absorption ratio and total hardness. In this study, the obtained data placed in the XLSTAT software. Then, the homogeneity and Mankendal numbers were drawn using Homogeneity and Petit tests in a period of 40 years. Also, the Paiper, Duru, Shuler and Wilcox diagrams were drawn in Ghorbaghestan and Doabmerck stations using the Aqua Chem software. Results: The classification results of Wilcox in Ghorbaghestan and Doabmerck stations showed that the samples placed in the class slightly salty (C2S1);therefore, the river water in these stations was almost suitable for agricultural. The Shuler diagram showed that the water quality was inappropriate for drinking in Ghorbaghestan and Doabmerck stations. Conclision: For improving the quality of river water and its efficient use, point and non-point pollutants entry into the river water especially urban and non-urban sewage should be prevented with long-term plans.
Soheil Sobhanardakani; Samireh Mahmodnezhad; Masoumeh Heydari
Abstract
Background & Objective: Heavy metals being among the major pollutants of aquatic ecosystems are considered as high-toxicity pollutants for organisms due to the non-biodegradable and persistent potential in the environment. Therefore, this study was carried out to analyse the presence of heavy metals ...
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Background & Objective: Heavy metals being among the major pollutants of aquatic ecosystems are considered as high-toxicity pollutants for organisms due to the non-biodegradable and persistent potential in the environment. Therefore, this study was carried out to analyse the presence of heavy metals (Zn, Cd, Cr and Cu) in water of Marivan River in 2013. Material & Methods: In this cross-sectional study, forty samples were taken from five selected stations during spring and summer seasons in 2013. After taken samples preparation, the concentrations of metal ions were investigated by spectrophotometry with three replications. All statistical analyses were performed using the SPSS 19.0 statistical package (p<0/05). Results: The results showed that the mean concentrations of metals (µg/l) in water samples for spring season were equal to 26.20±11.34, 0.73±0.06, 1.50±0.11 and 121.10±14.05 for Zn, Cd, Cr and Cu, respectively and in water samples for summer season were equal to 27.10±24.72, 0.72±0.05, 1.50±0.16 and 123.80±31.27 for Zn, Cd, Cr and Cu, respectively. Also, the mean concentrations of the evaluated metals compared with WHO and Iran DOE permissible limits showed a significant difference (P<0.05). That is, the mean concentrations of Zn, Cd, Cr and Cu were significantly lower than the permissible limits in both spring and summer seasons. Conclusion: Although the water of Marivan River was not contaminated to heavy metals during the study period. But due to the establishment and development of industrial, urban and agricultural activities along the river and its uncontrolled discharges of wastewater into the river, pollution and decrease of water quality in the near future is not unexpected.
ghorban asgari; Javad Faradmal; Abdolmotaleb Seid-mohammadi; Halime Almasi; somaye akbari
Abstract
Background and objective: Industrialization has led not only to an increase in water demand, but also to an increase in water pollution due to the discharge of polluted industrial wastewaters with high salt content, and the organic compounds such as phenol into the water bodies. This ...
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Background and objective: Industrialization has led not only to an increase in water demand, but also to an increase in water pollution due to the discharge of polluted industrial wastewaters with high salt content, and the organic compounds such as phenol into the water bodies. This study aimed to investigate the efficiency of electrocuagulation and electro-Fenton processes in phenol removal from saline wastewater using Taguchi exprimental design method. Material and methods: This experimental study was performed in a reactor (1 liter) with synthetic phenolic saline wastewater. In this study for electrocoagulation process, the effects of five operation parameters on phenol removal efficiency including reaction time (20-80 min), electrolyte (1-4%), pH (3-5-7-9), initial phenol concentration (500-1000-1500-250 mg/L) and current density (4-16 mA/cm2) were investigated in four levels by Taguchi L16 orthogonal array. Also for electro-Fenton process, the effects of six operation parameters on removal efficiency in five levels including reaction time (20-80 min), electrolyte (0-4%), pH (2-3-4-6-8), initial phenol concentration (250-500-1000-1500-2000), current density ( 0-16mA/cm2) and hydrogen peroxide (50-300mg/L) were evaluated by Taguchi L25 orthogonal array. The concentration of phenol was determined according to the estandard method in spectrophotometric wavelength of 500 nm. Results: Experimental data showed that the optimum phenol elimination condition in electrocuagulation process was initial phenol concentration of 250 mg/L, pH = 5, electrolyt = 3%, curent density of 8 mA/cm2 and reaction time of 60 min. The most influential factor in removal efficiency was the initial concentration (63.2%), and the lowest effect belonged to the electrolyt (4.2%). The optimum phenol removal condition for electro-Fenton process was initial concentration of 250 mg/L, pH:3, electrolyt:2%, hydrogen peroxide:150 mg/L, current density of 8 mA/cm2 and 20 mine contact time. The most influential factor in elimination efficiency was the curent density (29.12%), and the lowest influence on response variable belonged to the reaction time (3.08%). Conclusion: This study showed the electro-Fenton process was effective in the removal of phenolthat can be used as an appropriate process in wastewater treatment.
mahin karbar; aliasghar najaf poor; hossein alidade; Habibollah Esmaily
Abstract
Introduction: Daily excreted large amounts of waste from human communities in different ways. A significant portion of this waste consists of organic material. The recycling of these materials and using them in different ways prevent the damage caused to the environment and conserve resources and energy ...
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Introduction: Daily excreted large amounts of waste from human communities in different ways. A significant portion of this waste consists of organic material. The recycling of these materials and using them in different ways prevent the damage caused to the environment and conserve resources and energy is human attention. One of the appropriate methods of disposal of these wastes, production of organic fertilizer, vermicompost is. Objectives & ( hypothesis OR questions): Given that the municipality Ghochan, rotted cow manure and dried leaves of the trees used to produce vermicompost In this study the vermicompost production of cow manure, fruit waste, paper, sawdust and leaves (as carbon source) and germination index vermicompost is examined To finally be able to obtain the best additive to produce vermicompost. Materials & Methods: 5 treatments that are used to carry out the plan include: cow manure- Fruit lesions- Sawdust- leaf- Paper- Composition of the waste. Results: Used waste includes waste sawdust, fruit, paper, leaf and composition of the waste is suitable for vermicomposting is Eisenia fetida earthworms and proper nutrition. Waste paper to produce vermicompost alone is not suitable and it is better to prepare vermicompost should be used in combination with other organic wastes.. Conclusion: Changes of ash and carbon and C / N ratio indicates the fact that virtually After 70 days, the bedding materials are firmly established.