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Survey of PAC Performance for Removal of Turbidity, COD, Coliform Bacteria, Heterotrophic Bacteria from Water of Karoon River
A Mirzaei, A Takdastan, N Alavi Bakhtiarvand,
Volume 4, Issue 3 (1 2011)
Abstract

Backgrounds and Objectives: Selection of  proper coagulants for turbidity removal and determination of effective methods to reduce coagulants dose and related costs in water treatment plants is of critical importance. The present study investigates the effect of returned sludge on improving the performance of poly-aluminum chloride (PAC) in turbidity, coliform bacteria, heterotrophic bacteria removal from drinking water during rapid mixing phase.
Materials and Methods: In order to determine the optimal returned sludge volume injected during rapid mixing with PAC for turbidity, total coliform and hetrophic bacteria, experiments were conducted based on variables such as injected silt volume (from 0 - 125 ml), and varying turbidities from 58 - 112 NTU. At the end of each JAR experiments, remaining turbidity , microbial parameters of samples were measured . Coagulant efficiency in turbidity removal and microbial parameters were determined by Covariance, Duncan analyses and graphs were drawn by MS Excel . The results statistically showed significant among variables (P<0.05).
Results: The results showed that the maximum turbidity removal efficiency of 98.92 at 30 ppm was 10 ml while the maximum turbidity removal efficiency of 98.31 at 10 ppm was 4 ml. The maximum total coliform removal efficiency  of 95.68 obtained for 10 ppm in 10 cc injected sludge volume.
Conclusion: This study shows that addition of returned sludge to flash mixing can reduce the turbidity of samples.


Distribution Survey of Electric and Magnetic Field intensity  at a High Voltage Electricity Post in Zanjan City  using GIS Technology
Faramarz Majidi, Somaieh Alavi, Reza Azimi Pirsaraei, Abdollah Heidary, Farhad Asgari,
Volume 5, Issue 3 (21 2012)
Abstract
MicrosoftInternetExplorer4 Background and Objectives: Electric and magnetic fields in the workplace are one of the detrimental factors of power plants, transmission lines, electrical wires, and electrical equipments, therefore, exposure to these fields might be harmful for human health. This study aimed to provide information about intensity of the electromagnetic fields at the high voltage electricity posts and its comparison with the threshold limit value (TLV). 
Materials and Methods: The study was conducted at one of the high voltage electricity post in Zanjan City having 63, 230, and 400 KV power transmission lines. After identifying  stations and measuring the intensity of these fields, GIS maps were prepared and the values were compared with permissible values.
Results: The measured magnetic flux density at different parts of the high voltage post showed that the lowest and  highest intensity were 1.69 and 153.7 mG respectively which were lower than the ACGIH TLVs.The lowest and  highest intensity of the electric field  were 0.008 and 38.07 KV/m respectively. The highest value belonged to the 400 KV line, which exceeds the recommended ACGIH TLV (25 KV/m).
Conclusion: According to the results, the magnetic field intensity was below the TLVs, but the intensity of electric field measured in the 400 KV line was greater  than its TLVs. Thus, the strategies and recommendations for reducing exposure should be taken.

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Assessment of Phytoremediation Efficiency on reducing oilhydrocarbons from clay-silt soil using Aeluropus littaralis
Sn Alavi Bakhtiarvand, M Ahmadimoghadam, I Parseh, N Jafarzadeh, M Chehrazi, Mostafa Chorom,
Volume 7, Issue 1 (7-2014)
Abstract

Background and Objectives: Soil polluted with total petroleum hydrocarbon (TPHs) is a great threat to human health. Phytoremediation, the use of vegetation for treatment of contaminated soils, is an attractive and cost-effective alternative to reduce pollutant from soil. This paper evaluates the effects of the plant and nutrients on the removal of TPHs from soil. Material and methods: Soils were collected at depth of 0-30 cm, and then polluted with 1 and 2.5 % w/w of crude oil. After preparing the experimental pots, Rhizosphere microbial number, plant biomass, and residual TPHs were determined. TPHs and heterotrophic bacterial number were measured by GC and HPC method respectively. Data were analyzed using the Statistical Package for Social Sciences (SPSS 17 for Windows) software and Excel. Results: It was found that the average percent of TPH removal in planted soil (28.42%) was higher than that in unplanted soil (12.2%) (p<0.05). Moreover, the average percent of TPH removal in treatments received nutrient and free nutrient treatments was 35.5and 17.7% respectively. Conclusion: Generally compared with the other studies, high clay and salinity of the experimental soil had a negative effect on phytoremediation efficiency. Finally, regarding to the high clay and salinity of the experimental soil, the phytoremediation efficiency was relatively desirable.


Experimental study of adsorption of amoxicillin residue from water samples using nanocomposite based on zirconium metal-organic frameworks and porous polymers
Yadollah Yousefzadeh, Vida Izadkhah, Soheil Sobhanardakani, Bahareh Lorestani, Sedigheh Alavinia,
Volume 16, Issue 4 (3-2024)
Abstract
Background and Objective: Antibiotics as emerging pollutants are harmful to environmental health. Therefore, this study was conducted to investigate the efficiency of Uio-66-NH2@CS-Iso-Gu nanohybrid for the removal of amoxicillin (AMX) from aqueous solutions.
Materials and Methods: In this study, for the first time, guanidine and isocyanate monomers are cross-linked with chitosan. The combination of this polymer with organometallic compounds contributes to its chemical/thermal stability and reusability. Uio-66-NH2@CS-Iso-Gu nanohybrid was characterized using X-ray diffraction (XRD), Scanning electronic microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA), and BET methods. Also, the effects of pH, initial concentration of AMX, contact time, and temperature were evaluated. Moreover, isotherm, kinetic and thermodynamics studies were performed.
Results: The results of TGA analysis showed that Uio-66-NH2@CS-Iso-Gu nanohybrid was resistant to temperatures up to 400 °C. Also, optimal adsorption of AMX occurred in the first 25 min. The synthesized nanohybrid has a surface area of 101.2 m2/g and a type IV isotherm. Acidic groups were present on the synthesized nanohybrid surface based on the pHpzc = 4.7. Langmuir (for 25 °C and 45 °C) and Freundlich (for 65 °C) isotherm models and pseudo-second-order kinetic models are more appropriate to fit the adsorption data with the experimental data. The maximum adsorption capacity of the synthesized nanohybrid was equal to 56.49, 40.65, and 0.382 mg/g at temperatures of 25°C, 45°C, and 65°C, respectively. Based on the findings, Uio-66-NH2@CS-Iso-Gu nanohybrid could be used for up to five cycles without significantly reducing their performance.
Conclusion: The results showed that Uio-66-NH2@CS-Iso-Gu nanohybrid has a significant efficiency for removing AMX and could be used as an effective adsorbent for the treatment of wastewater containing pharmaceutical residues.
 

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