Showing 10 results for Alizadeh
Z Farahmand Kia, M.r Mehrasbi, M.s Sekhawatju, A.sh Hasanalizadeh, Z Ramezanzadeh,
Volume 2, Issue 4 (9 2010)
Abstract
Backgrounds and Objectives : Heavy metals in dust can enter to the human body through ingestion andinhalation. They can pollute the water and soil resources via atmospheric precipitation and accumulate in the plants tissue and enter human body by water and food. The aim of this study was measurement of the heavy metals in wet and dry atmospheric precipitation and effects of pollution sources at the ground surface on the concentration of heavy metals in the atmospheric precipitations.
Materials and Methods: In this study the zanjan city was divided into 5 zones and wet and dry precipitations were collected in autumn, winter and spring (2008- 2009) from zones. The concentrations of Pb, Cd, Cr and Zn the collected precipitations were determined by Atomic Absorption spectroscopy method.
Results: The averages of concentrations of Pb, Cd, Cr and Zn were 0.082, 0.286, 0.018, and 0.009 (mg/m 2.d)respectively. The correlation coefficients between Pb-Zn was 0.8 (P<0.01) and for Cr-Cd, Cd-Pb, and Cr-Pb were 0.89, 0.58 and 0.61 respectively.
Conclusion: The results showed that the industrial sources of heavy metals play the main role in concentration of heavy metals in wet and dry atmospheric precipitation in Zanjan.The correlation coefficients showed that the lead and zinc result from a common source. This source can be the lead and zinc factories locating around the city. The measurement of heavy metals in atmospheric precipitation shows the effects of anthropogenic sources in air quality. The heavy metals concentration in atmospheric precipitation can be use as air pollution index.
A. Alizadehdakhel, A. Ghavidel, M. Panahandeh,
Volume 3, Issue 1 (3 2010)
Abstract
Backgrounds and Objectives: The dispersion of particulate matter has been known as the most serious environmental pollution of cement plants. In the present work, dispersion of the particulate matter from stack of Kerman Cement Plant was investigated using Computational Fluid Dynamics (CFD) modeling.
Materials and Methods: In order to study the dispersion of particulate matter from the stack, a calculation domain with dimensions of 8000m × 800m × 400m was considered. The domain was divided to 936781 tetrahedral control volumes. The mixture two-phase model was employed to model the interaction of the particulate matter (dispersed phase) and air (continuous phase). The Large Eddy Simulation (LES) method was used for turbulence modeling.
Results: The concentration of particulate matter in the whole calculation domain was computed. The predicted concentrations were compared to the measured values from the literature and a good agreement was observed. The predicted concentration profiles at different cross sections were analyzed.
Conclusion:The results of the present work showed that CFD is a useful tool for understanding the dispersion of particulate matter in air. Although the obtained results were promising, more investigations on the properties of the dispersed phase, turbulent parameters and the boundary layer effect is needed to obtain more accurate results.
H Khorsandi, A Mohammadi, F Kariminejad, M Haghighi, R Alizadeh,
Volume 7, Issue 4 (1-2015)
Abstract
Background & Objectives: Entering LAS through the wastewater plant’s effluent to water resources causes taste and odor changes, aquatics death, oxygen transfer limitation, and disorders in water treatment processes. Therefore, the study objective was to determine optimum conditions for fenton oxidation process to remove linear alkyl benzene sulfonate from aqueous environments using taguchi method and its requirement evaluation for additional treatment of Biolac effluent. Materials &Methods: LAS removal using Fenton oxidation was evaluated in a 500 mL laboratory-scale batch reactor. In order to save the costs, to determine the optimum conditions of the Fenton oxidation, 25 runs were computed using Taghuchi method by Minitab 16 software. Sampling and required tests were performed based on standard methods examination for water and wastewater. For evaluation of Biolac process sufficiency in LAS removal, biolac efficiency in Urmia Wastewater Treatment Plant was studied in 2012. Results: Based on the LAS removal and chemicals required, Minitab software (Ver. 16) recommended the optimum conditions of Fenton oxidation at 900 mg/L H2O2, 170 mg/L Ferrous ion, pH of 4, and reaction time of 20 minutes. It was found that the Fenton oxidation for LAS removal had 86.5% efficiency under optimum condithions and it was second order reaction with the rate coefficient of 0.0152 L/mg.min. Biolac process does not need any additional treatment due to meeting LAS standard in municipal wastewater treatment. Thus, this process decreased annually mean LAS from 5.28 mg/L to 0.734 mg/L in municipal wastewater. Conclusion: Although the Fenton oxidation appears as a chemical process with high efficiency in the removal of LAS, the low efficiency of COD corresponding to the LAS indicated partial decomposition of linear alkyl benzene sulfonate by Fenton oxidation.
M Malakootian, A. H Mahvi, H Jafari Mansoorian, M Alizadeh, A.r Hosseini,
Volume 8, Issue 2 (8-2015)
Abstract
Background and Objective: Phenol and phenol derivatives in industrial wastewater are among the pollutants with priorities. The high cost and low efficiency of some routine treatment processes of industrial wastewater has limited their use. One of the new methods under consideration is, nowadays, adsorption using carbon nanotubes. This study was conducted in order to evaluate the application of alumina-coated multiwall carbon nanotubes in eliminating phenol from synthetic wastewater. Materials and Methods: This study was performed in laboratory at batch scale. Multi-wall carbon nanotubes were coated with Alumina. The concentration of phenol was determined by spectrophotometer through photometry. The effect of pH changes, dosage of adsorbent, contact time, the initial concentration of phenol, temperature, and the concentrations of different salts on the efficiency of absorption was evaluated. Then, the absorption results were described using the Langmuir and Freundlich isotherms and the synthetics of absorption. Results: It was found that absorption efficiency increased significantly by decreasing the initial concentration of phenol and pH and by increasing the carbon nanotube dosage, temperature, and contact time. On the other hand, the maximum elimination of phenol from the solution (98.86%) occurred at 4 mg/l phenol concentration, under acidic conditions (pH=3), at adsorbent dosage of 0.05 g/l, at temperature of 45°C, and contact time of 10 min. Evaluation of the regressions isotherms showed that the process follows the Langmuir model and second-degree synthetic absorption. Conclusion: The high efficacy (98%) of the adsorption process in this study showed that alumina-coated multiwall carbon nanotubes have a good capability in eliminating phenol and can be used as an appropriate and new method for eliminating phenol and its derivatives from wastewater.
S Valizadeh, Z Shekari,
Volume 8, Issue 2 (8-2015)
Abstract
Background and Objective: Significant increase in population and as a result, the production of excessive waste has recently made attention to municipal solid waste management a necessary issue. The objective of this study was to use matrix-based EIA process in order to determine best waste management option in Birjand City and to suggest appropriate solutions to managers and planners of this city. Materials and Methods: Assessing the environmental impacts of waste management options was done using Iranian Leopold Matrix. Through this method, the environmental impacts of waste management options were determined in the Birjand City. The options were Open dumping, Recycling, Composting, and Sanitary damping. Results: The results indicated that Open dumping with a final score of -3.06 had the highest environmental impact and was introduced as the fourth preference. In addition, composting with final score of -2.34 has the lowest environmental impact compared with other options. Conclusion: About 76.95% of the composition of municipal solid waste of Birjand City is household waste therefore, putrescible organic materials are the predominant waste. Thus, according to the results of the Iranian Leopold matrix method, composting option was introduced as the first priority and the most logical option for waste management in the Birjand City.
A Gholampour, Ms Hassanvand, R Nabizadeh, Z Alizadeh, Ah Mahvi,
Volume 9, Issue 3 (12-2016)
Abstract
Background and Objective: The present study was carried out to determine the amount and ionic characterization of TSP and PM10 aimed at identifying the potential emission sources of particulates in the ambient air of Tabriz.
Materials and Methods: TSP and PM10 samples were collected by two high volume samplers during September 2013 to August 2014. Water-soluble ions in particulate matter were extracted using ultrasonic method and were identified by ion chromatography. Using Stata12 software, linear regression analysis was performed between the ions to determination of the major ionic component of the particulates. In addition, in order to identify the potential emission sources of PM10, the rotation varimax model was used.
Results: Total measured water-soluble ions in TSP and PM10 of the urban sampling site were 20.33±20.77 and 16.04±14.08 µg/m3, respectively. Among all detected ions, sulfate (8.69±5.79 µg/m3) and nitrate (8.47±7.9 µg/m3) were the dominant constituents followed by calcium and sodium.
Conclusion: The modeling results revealed that the soils of surrounding ground together with secondary PM and also resuspension of PM from polluted soil account for 80 percent of PM10 mass.
Zeinab Alizadeh, Kavoos Dindarloo, Mohsen Heidari,
Volume 14, Issue 3 (12-2021)
Abstract
Background and Objective: Heavy metal (HM) pollution of settled dust on the interior surfaces of elementary schools may affect the health of young students; hence, the health risk of such pollution should be assessed. Therefore, the aims of this study were to measure the content of heavy metals in the settled dust in the indoor of elementary schools in Bandar Abbas and to assess the attributed health risks.
Materials and Methods: In this study, dust samples were collected from the interior surfaces of elementary schools in Bandar Abbas. Settled dust samples were digested using aqua regia solution and then their metals contents were measured using ICP-OES. To assess the health risk attributed to this pollution, daily intake doses through ingestion, inhalation and skin absorption routes were estimated. Then, non-carcinogenic and carcinogenic risks were calculated considering the daily intake doses and toxicity factors.
Results: The average concentrations of arsenic, cadmium, cobalt, chromium, nickel and lead in settled dust were 5.45, 0.58, 11.44, 69.72, 83.95 and 66.72 mg/kg, respectively. The non-carcinogenic risk level for all metals was below threshold, while the carcinogenic risk level for arsenic (2.18×10-6) exceeded the threshold.
Conclusion: This study showed that the settled dust in elementary schools of Bandar Abbas is polluted with various levels of heavy metals. Health risk assessment showed that the exposure to dust containing heavy metals in the elementary schools of Bandar Abbas does not pose significant non-carcinogenic risk, but the carcinogenic risk of As exceeded the threshold limit and should be considered.
Samira Sheikhi, Aran Moshiri, Hassan Aslani, Shamseddin Alizadeh,
Volume 15, Issue 4 (3-2023)
Abstract
Background and Objective: One of the main ways of transmitting diseases is drinking water, so the safety of drinking water is an important issue for consumers, water suppliers, operators, and health officials. This study was conducted to identify and semi-quantitative evaluation and prioritization of risks in the drinking water supply system of Bostan Abad city.
Materials and Methods: In order to evaluate and document the key elements of WSP and identify the steps that need improvement, the quality assurance tool of the water safety plan (WSP-QA TOOL software) was used, and then based on the guide of the water safety plan from the WHO and the International Association Water safety, WSP team formed. Then the water supply system of Bostan Abad city from the farthest point of the basin to the last consumption point was inspected and described.
Results: The results showed that the highest number of risks are in the water supply sources, distribution network, and point of consumption, respectively. Also, the most vulnerable part of the system was identified as the disinfection unit and storage tanks due to biological and chemical contamination caused by equipment failure and improper preparation of chlorine solution.
Conclusion: In summary, it can be said that carrying out the necessary reforms can play an effective role in reducing the risk potential in times of crisis, which should be given serious attention by water industry officials.
Somayeh Alizadeh Attar, Alireza Pardakhti, Khosrow Ashrafi, Mohammad Sadegh Hassanvand,
Volume 18, Issue 1 (5-2025)
Abstract
Background and Objective: Black carbon is a byproduct of the incomplete combustion of fossil and biomass fuels. Long-term exposure to black carbon has been linked to an increased risk of lung cancer and cardiovascular diseases. This study aims to evaluate the carcinogenic and non-carcinogenic risks associated with black carbon exposure in the ambient air of Tehran.
Materials and Methods: Hourly black carbon concentrations were collected from the air quality monitoring stations operated by Tehran's Air Quality Control Company and averaged to calculate annual means for 2021, 2022, and 2023. The risk assessment for black carbon exposure in Tehran was conducted using the US EPA model.
Results: The findings reveal that in Tehran, the carcinogenic risk index (CR) due to black carbon exposure in ambient air is higher for adults than for children. The non-carcinogenic risk quotient (HQ) for both age groups remains below the threshold value of one, indicating a low and negligible non-carcinogenic risk. However, children demonstrate a higher HQ compared to adults. The lifetime cancer risk associated with black carbon exposure is calculated to be 1.4 × 10-3, while the annual cancer risk is estimated at 0.02 × 10-3.
Conclusion: The results indicate that the carcinogenic risks associated with black carbon exposure exceed acceptable levels for both adults and children. Adults face a cancer risk six times greater than children, though the non-carcinogenic risk is assessed as low. Reducing black carbon emissions is critical for improving public health in traffic-congested cities, and further research on this topic is strongly recommended.
Mahmood Alizadeh Sani, Arezou Khezerlou, Mohammad Rezvani-Ghalhari, Gholamreza Jahed-Khaniki,
Volume 18, Issue 3 (12-2025)
Abstract
Background and Objective: Melamine is a chemical compound commonly used as an adulterant in food products. In this study, a fluorescence-based sensor utilizing an aluminum metal-organic framework (Al−MOF) was developed for the detection of melamine in milk powder.
Materials and Methods: In this study, Al-MOF was employed as a sensing material due to its high fluorescence properties and strong ability to adsorb melamine. Using fluorescence techniques, the sensitivity and selectivity of the sensor towards melamine were evaluated over a concentration range of 0 to 400 nanomolar (nM).
Results: The melamine concentration was determined based on the reduction in the fluorescence intensity of the Al-MOF. The effects of different parameters such as pH, reaction time, and concentration, on the performance of the designed sensor were evaluated. Under optimized conditions (pH = 9, reaction time < 1 min, and Al–MOF concentration of 30 mg/L), a good linear relationship (R2 = 0.99) was observed between fluorescence intensity and melamine concentration in the range of 0–400 nM, with a detection limit of 38.5 ppb. However, the limit of detection (LOD) for HPLC method was approximately 90 ppb, indicating that the designed sensor has higher sensitivity (about 2.3 times). The sensor also exhibited good selectivity for melamine. The recovery percentage and relative standard deviation (RSD) were found to be 97-103% and 1.2-2.8%, respectively.
Conclusion: This sensor can serve as an effective tool for quality control in dairy products due to its simplicity and rapid detection capabilities.
