Iranian Journal of

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Background and Objectives: Weather pollution, caused by Ozone (O3) in metropolitans, is one of the major components of pollutants, which damage the environment and hurt all living organisms. Therefore, this study attempts to provide a model for the estimation of O3 concentration in Tabriz at two pollution monitoring stations: Abresan and Rastekuche.
Materials and Methods: In this research, Artificial neural networks (ANNs) were used to consider the impact of the meteorological and weather pollution parameters upon O3 concentration, and weight matrix of ANNs with Garson equation were used for sensitivity analysis of the input parameters to ANNs.
 Results: The results indicate that the O3 concentration is simultaneously affected by the meteorological and the weather pollution parameters. Among the meteorological parameters used by ANNs, maximum temperature and among the air pollution parameters, carbon monoxide had the maximum effect.
Conclusion: The results are representative of the acceptable performance of ANNs to predict O3 concentration. In addition, the parameters used in the modeling process could assess variations of the ozone concentration at the investigated stations.

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Background and Objectives: The development a low-cost and high efficiency water treatment technology to decolorize the organic dye effluents is desirable due to overwhelming discharge of organic synthetic dyes into the natural water cycle during the dying process. In this study, the decolorization of Acid Black 26, as the model organic contaminant, was investigated using immobilized nano-sized TiO2 particles as the photocatalyst. Material and Methods: Sackcloth fiber was used as a support to immobilize TiO2 nanoparticles. The structural properties of the immobilized photocatalysts were characterized by XRD and SEM. UV-Vis absorption spectroscopy and the measurement of the chemical oxygen demand (COD) were also used for the process performance studies. Moreover, we investigated the effects of the oxidant H2O2, initial dye concentration, the presence of anion and pH on the photocatalytic degradation efficiency. Results: The XRD results did not show significant changes in the structure of TiO2 as a consequence of the immobilization procedure. The formation of titania crystallites in the sackcloth fiber was confirmed by SEM. Experimental results showed that after 60 min, the degradation percentage of Acid Black 26 with the immobilized TiO2 particles was about 60%, which was higher than that with TiO2 slurry. Based on the COD results, after 3 h, the TiO2-coated sackcloth fiber effectively decomposed 94% of the organic compounds presenting in dye solution during the degradation of Acid Black 26. Conclusion: The titania nanoparticles immobilized on the sackcloth fiber can be used as an effective and environmental friendly photocatalyst in the degradation of colored wastewater.

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Background and Objectives: Among the heavy metals cadmium is of considerable environmental and health significance because of its increasing mobilization and human toxicity. The objectives of this research were to synthesize SDS modified magnetite nanoparticles (Fe3O4) and to determine its efficiency in cadmium removal from aqueous solutions. Materials and Methods: Modified magnetite nanoparticles were synthesized and the effects of pH and contact time on cadmium removal efficiency were investigated in batch system. Then kinetics and isotherm models coefficients were determined in the optimum pH and equilibrium time conditions. Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infra red (FTIR) were used to characterize the modified magnetite nanoparticles synthesized. Results: The SEM results showed that the diameter of the particles is 40-60 nm. It was found that the optimum pH value for maximum adsorption of 10 mg/L cadmium by 0.1 g adsorbent in 12 hr was 6. Kinetic study showed that the equilibrium time was 30 min. The adsorption kinetics fitted well using the Ho pseudo second-order kinetic model however, the adsorption isotherm could be described by the Freundlich model. The maximum adsorption capacity of modified magnetite nanoparticles for Cd2+ was found to be 9.604 mg/g. Conclusion: The results of this study indicated that the modified magnetite nanoparticles can be employed as an efficient adsorbent for the removal of cadmium from contaminated water sources

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Background and Objectives: Soil pollution by oil compounds is a serious environmental and ground water problem throughout the world. Total petroleum hydrocarbons (TPH) are a combination of many distinctive compounds. Some of these compounds in exposure with human and animal can cause cancer, disorder central nervous system, liver and lungs affects. The objective of this research was to investigate gasoline removal (C10 – C 28) using Brij 35 and Tween 80 from polluted soil. Materials and Methods: In this experimental study, the efficiency of soil washing with nonionic surfactants (Brij 35, Tween 80) for remediation of gasoline polluted soils was studied. The effects of soil washing time, agitation, surfactant concentration, and pH on the removal efficiency were studied. Results: The results showed that gasoline removal efficiency increased with increasing agitation speed and washing time. In addition, it was found that removal efficiency of gasoline was decreased by increasing surfactant concentration. But, increasing pH did not have remarkable effect on removal efficiency of gasoline. The efficiencies of Tween 80 and Brij 35 for removal of gasoline under optimal condition were 70 -80 and 60- 65% respectively. Conclusion: The results showed that soil washing with non ionic surfactants was effective in removal of gasoline from polluted soil and it can be recommended for treating surface soil polluted.

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Background and objectives: In this research, an innovative drinking water quality index for assessing water resources as “modified drinking water quality index (MDWQI)” was developed and applied for evaluating all of the groundwater resources utilized for community water supply in urban areas of Iran during 2011. Materials and methods: Twenty-three water quality parameters and relevant Iranian standards for drinking water quality were selected as input parameters and benchmarks respectively. The MDWQI is calculated using three factors including the number of parameters that excurse benchmarks, the number of measurements in a dataset that excurse benchmarks and the magnitude of excursions. The MDWQI scores range from 0 to 100 and classify water quality in five categories as excellent (95-100), good (80-94), fair (65-79), marginal (45-64), and poor (0-44). Results: According to the MDWQI value, about 95% of the groundwater resources were in the good condition and the others were in the fair or marginal condition also the best and the worst water quality of water resources were observed in Ardebil Province and Qom Province respectively. The three parameters of fluoride, magnesium, and nitrate recorded the highest rates of violation to be 74, 32, and 13% respectively. Conclusion: The nationwide average score of the MDWQI was 85 (good description). This study indicated that the MDWQI and its sub-indices could describe the overall water quality of water bodies easily, reliably and correctly and have the potential suitability for extensive application all over the world.

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Background and Objectives: On August 2012, two earthquakes measured 6 and 6.2 on the Richter scale took place in Eastern Azerbaijan province. Environmental Health Department is accounted as one of the main units for providing and supervising environmental sanitation services at the emergencies, therefore, the objective of this study was allocated to assess environmental health response performance in recent earthquake. Material and Methods: Through multi-stages stratified sampling, we selected 8 and 4 villages from the earthquake zones of Heris and Varzaghan respectively. The collecting data tools in this research were the WHO checklist in 7 categories, 14 subcategories, and 37 environmental health activities and also the minimum standards of Sphere Project checklist. The status of environmental health in each village was assessed using the mentioned checklists. This study was carried out with attendance of research team in earthquake zones 21 days after the occurrence of earthquake. Results: Among the 37 environmental health activities, 7 activities were the joint ones, which Environmental Health Department had to carry it out with the coordination of other related organizations. In other words, the environmental health has the supervising role in these activities. Totally, such activities had more nonconformities compared with the activities in which environmental health was administered as the main responder. The details of results have been expressed in the full text. Conclusion: Providing intra-sector coordination, prioritizing the needs of the affected population and considering the principles of community based management in the natural disaster are proposed as the recommendations of this study.

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Background and Objectives: Toxicity assessment of material related to nanotechnology is necessary before excess development of this industry. On the other hand, specific characteristic of nanomaterials can be used in disinfection of other material. In this study toxicity and antibacterial properties of nano-TiO₂ and nano-CuO were investigated with four bacterial species in solid media.

Material and Methods: Stock suspension of nanoparticles (10g-TSS/L) was diluted using Muller Hinton Agar to achieve 5-6000mg-TSS/L concentration. We prepared three Petri dishes for each concentration and refined bacteria were cultured on these Petri dishes. After culturing of these bacteria on the media containing nanoparticles, growth inhibition was determined. According to this data, 50% growth inhibition (EC₅₀), no observed effect concentration (NOEC) and 100% growth inhibition were determined.

Results: Our results showed that toxicity of TiO₂ is more than CuO in solid media. In this regard, nano-TiO₂ EC₅₀ for Escherichia coli, Bacillus subtilis, Staphylococcus aureus, and Pseudomonas aeruginosa was calculated 181, 571, 93 and 933mg-TSS/L respectively. These figures for nano-TiO₂ were 2550, 1609, 946, and 1231mg-TSS/L respectively.

Conclusion: This study showed that compared with other bacteria studied, E. aureus due to high sensitivity and E. coli due to high resistance to both TiO₂ and CuO nanoparticles are more proper as bioindicator in toxicity test and antibacterial test respectively.

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Background and Objectives: Water is essential for sustaining life & adequate safe supplies must be accessible to the public. Nowadays, people prefer to purchase bottled water for reasons including taste, convenience, following fashion, and its safety and sanitary conditions. According to the WHO guideline, it is of great importance to control the bottled water because of keeping it for longer period of time and at higher temperature in comparison with the water of distribution networks, reusing containers and bottles without adequate washing and disinfecting, and more growth of microorganisms having less important in the terms of health. The aim of this study was to investigate the microbial and physicochemical quality of bottled water in the stores of Qazvin City and to compare the aforesaid features with national standards and to check the quality with the bottles label.
 Materials and Methods: In this cross-sectional study, 51 samples of 11 bottled water brands with different production date were obtained. The features were studied in accordance with Standard Methods. Then, the data were analyzed by T-Test and one way ANOVA analysis using SPSS software. Eventually, the results were compared with the national standards, the WHO guidelines, and the product labels.
Results: Results showed lack of microbial contamination of the samples. Physically and chemically, all the parameters measured were below the national standards level. Study of conformity of the variables to the label indicated that mostly there was a significant difference between the values measured and the values listed on the product labels. Conclusion: Although the concentration of microbial, physical and chemical features of samples were in the extent of national standards, there was a meaningful difference between labels and measured values so that the average concentration of TDS, TH, SO4-2, Ca2+, Mg2+ and Na+ would be more than the label values and the average of the other parameters was lower than the label values.

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Background and Objectives: Kidney patients in each dialysis cycle are exposed to extremely large volume of water, which is in direct contact with the patient’s blood. Hence, the occurrence of any type of contamination in the water used can be very toxic to patients. Thus, quality of water plays an important role in patient well-being. The aim of our study was to investigate the quality of water used for hemodialysis in Kashan Akhavan hospital.
Materials and Methods: This cross-sectional descriptive study was conducted on water quality used for hemodialysis in Kashan Akhavan hospital during Oct.-Nov., 2011. During the study a total of 26 water samples were taken from the raw water and inlet of hemodialysis instrument. Collected water samples were analysed for Heterotrophic plate count, residual chlorine, pH , K⁺, SO₄^2- , Na⁺, F- ,Ca²⁺ , mg²⁺ ,No^3- , Hg⁺ , Cd²⁺, Cr⁶⁺, Zn²⁺, Cu²⁺, Se²⁺ ,Co²⁺,Ag ⁺and As²⁺ according to the standard methods for water and wastewater examination.
Results: Our results showed that the concentration of copper, zinc, cadmium, lead, chromium, and silver were 0.4, 0.6, 0.07, 0.05, 0.08, and 0.04 µgL^-1 respectively. In addition, concentration of the chemical elements and heavy metals did not exceed the standard level in any cases. Moreover, no microbial contamination was observed in the samples analyzed.
Conclusion: Based on the results obtained, all water quality parameters in hemodialysis ward of Kashan Akhavan Hospital were compatible with AAMI (Association for the Advancement of Medical Instrumentation) water quality Standards and no health risk threatens the kidney patients.

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Background and Objectives: Increasing waste tiers production has made the recycling of this solid waste a critical issue in the world. On the other hand, it seems contamination of groundwater to the petroleum pollutant like gasoline is a great threat to the health of societies in developing countries. The main objective of this study was gasoline removal from aquatic environment by waste tire derived activated carbon. Materials and Methods: In this study for preparation of activated carbon from waste tires, KOH was used for chemical activation process. We used argon gas to prevent precursor oxidation . We applied N2 gas and BET isotherm for characterization of the prepared activated carbon texture. Isothermal and kinetic models were used for defining gasoline adsorption characteristic to adsorbent, and thermodynamic studies were used to determine the effect of temperature. Results: Characterization results revealed that SBET and VTOTAL were 111.702m2/g and 0.124cc/g respectively. Langmuir and pseudo-second order models were the best isotherm and kinetic models for prediction of the adsorbent behaviors to adsorb gasoline. The Gibbs free energy changes were negative at all temperatures applied. Conclusion: Produced activated carbon has desired surface area and adsorptive capacity for gasoline adsorption in aquatic environments and it seems preparation activated carbon from waste tiers is cheap, effective and environment friendly.

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Background and Objectives: In arid and semi-arid regions, wastewater reuse has become an important element in agriculture. However, irrigation with this resource can be either beneficial or harmful, depending on the wastewater characteristics. The aim of this research was to investigate the soil bacterial and crops quality irrigated with treated wastewater. Material and Methods: This research was conducted on a maize field near the wastewater treatment plant in Shahr-e-kord in summer,2011. Plots were arranged in a randomized complete block design in 3 replications and 2 treatments, well water (W1) with fertilizer and effluent (W2). Results: At the end of growth season, soil samples were collected from depth of 0-5 and 5-15 cm and plant samples consisting of old and new leaves and seeds were collected for bacteriological analysis. According to bacteriological analysis, total number of positive lactose bacteria, total and fecal coliforms in depth of 0-5 cm was 42% more than depth of 5-15 cm. In the case of old leaves, total number of coliform and fecal coliform was 88 and 40 MPN/100 mL respectively. Moreover, for new leaves, it was 38 and 2 MPN/100 ml respectively. Conclusion: According the results, number of indicator bacteria in soil is decreased (about 35%) by passing time.

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Background and objective: Metal pollution has always been a major cause of contamination of environment and is considered as a major concern for food health. Worldwide, sturgeons are an important source of food and income. In this study, the human health risk due to consumption of caviar and muscle of Persian sturgeon (Acipenser persicus) were evaluated by measuring the concentrations of cadmium, nickel, vanadium and zinc in caviar and muscle samples. Material and Methods: A total number of 24 samples of Persian sturgeon were collected from two important sturgeon fishery zones in Guilan and Mazandaran Provinces and were stored at −20°C until chemical analysis. About one gram of each sample dried was added to 10 ml of concentrated (65%) supra-pure HNO3 (Merck, Darmstadt, Germany) in a Teflon PTFE tube and then it was incubated for 1 h at 40 °C in a hot block digester, followed by heating at 140 °C for 3 h. The samples digested were diluted to a measured volume using double deionized water. Samples were filtered through Whatman No. 1 filter paper, and the filtrate was stored until metal determination. Results: Mean Cd, Ni, V and Zn concentrations in muscle tissues were 0.005 ± 0.002, 0.06 ± 0.03, 0.13 ± 0.04 and 7.49 ± 3.07 µg/g wet weight basis respectively. The mean Cd, Ni, V and Zn concentrations in caviar samples were 0.007 ± 0.006, 0.09 ± 0.07, 0.12 ± 0.15 and 21.23 ± 5.75 µg/g wet weight basis respectively. Conculation: The mean concentrations of Zn, Cd and V in caviar and muscle samples were less than the permissible limits proposed by the United Kingdom's Ministry of Agriculture, Fisheries and Food (MAFF 2000) and World Health Organization (W.H.O.). The guidelines for Cd, V and Zn are 0.2, 0.5 and 50 µg/g wet weight respectively. Therefore, the measured concentrations for these particular metals are below the published guidelines, and the levels would appear not to constitute any threat to the human population that may consume sturgeon or caviar obtained from these study locations.

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Background and Objectives: Modelling and specifying mathematical equations to predict and estimate a bioprocess is one of the important applications of bioengineering. Objective of this study was to identify proper and exact equations to describe various changes in biodegradation of heavy fuel oil through investigating kinetic models and third parametric equation of Ch. Materials and Methods: To submit an exact and perfect enough statement, two different experimental conditions were used in which isolated indigenous bacteria from environment were employed. Experiments were carried out during ten days and microbial growth, mazut concentration, pH, and electric potential curves were drawn. Fitting data onto kinetic models and Ch equation resulted accuracy and their constants. Results: We found that kinetic models were not capable to present an accurate and appropriate statement under different conditions. On the other hand, Ch equation by extending very accurate equations could satisfyingly illustrate mazut, pH, and electric potential changes based on time and microbial growth. Conclusion: Ch equation by reason of using two variables for computation of third variable and correctly selecting variables could describe various changes in mazut biodegradation under different conditions via mathematical statements. Moreover, it is possible that this equation can be used to study other various phenomena in future.

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Background and Objectives: Rivers are the most important resources supplying drinking, agricultural, and industrial water demand. Their quality fluctuates frequently due to crossing from different regions and beds as well as their direct relationship with their peripheral environments. Thus, it is essential to be considered the surveying and predicating changes in the water qualitative parameters in a river. In this study, in order to estimate some of the qualitative parameters (Total dissolved solids, electrical conductivity and sodium absorption rate) for Tehran Jajroud and Kermanshah Gharasu rivers, we used wavelet-artificial neural network (W-ANN) hybrid model during a statistical period of 24 years. Methods: We compared W-ANN model with ANN model in order to evaluate its capability in detecting signals and separating error signals for estimating water quality parameters of the abovementioned rivers. The evaluation of both models was performed by the statistical criteria including correlation coefficient, the Nash-Sutcliffe model efficiency coefficient (NS), the root mean square error (RMSE) and the mean absolute error (MAE). Results: The results showed that the optimized W-ANN with correlation coefficient of 0.9 has high capability to estimate SAR parameter in the stations studied. Moreover, we found that W-ANN had less error and higher accuracy in the case of EC and TDS parameters rather than ANN model. Conclusion: W-ANN proved high efficiency in forecasting of the water quality parameters of rivers, therefore, it can be used for decision making and assurance of monitoring results and optimizing the monitoring costs.

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Background & Objectives: The aim of the study was to design and implement integrated solid wastes management pattern in Shahroud industrial area, to evaluate the results, and to determine possible performance problems. Materials & Methods: This cross - sectional study was carried out for 4 years in Shahroud industrial area and the implementation process included: 1. qualitative and quantitative analysis of all solid wastes generated in the area, 2. determining the current state of solid waste management in the area and identifying programs conducted, 3. designing and implementation of integrated management pattern including design and implementation of training programs, laws, penalties and incentives, and illustrating and implementing programs for all factories, and 4. monitoring the implementation process and determining the results. Results: Annually, 1,728 tons of solid waste is generated in the area including 1603 tons of industrial waste and 125 tons of municipal wastes. By implementing this pattern, two separated systems of collection and recycling of domestic and industrial waste were launched in this area. Moreover, consistent with the goals, the amount of solid waste generated and disposed in 2011 was 51.5 and 28.6 kg per 100 million Rials production respectively. In addition, 42 and 40% of the industrial waste and paper were recycled. Conclusion: Results showed that implementation of this pattern, i.e. running source separation, training programs, capacity building, providing technical services, completing chain of industries and strengthening the cooperation between industrial estate management and industrial units could greatly reduce the waste management problems.

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Background and Objectives: bisphenol A and nonylphenol are xenoestrogen materials used as a monomer of plastics in widely volume in the production of plastic materials especially mineral water bottles and disposable plastic containers. In this study, we investigated the potential of migration of bisphenol A and nonylphenol from disposable plastic containers into water at different temperatures and also from mineral water into water at different temperatures. Materials and Methods: We conducted bisphenol A and nonylphenol extraction from each sample through liquid-liquid extraction. For identification and quantitative determination of bisphnol A and nonylphenol, we used gas chromatography equipped with mass detector, and for quantitative determination of these two compounds, we used high-performance liquid chromatography equipped with fluorescence detector. Results: We found that increasing temperature increased significantly the rate of migration of these two compounds in the water. Moreover, it was revealed that only the presence of bisphenol A in water of mineral water bottles was detected and the increase in temperature also increases the rate of migration bisphenol A into water. Conclusion: In general, results of this study showed that improper storage of mineral water bottles and also use of disposable plastic containers for hot drinks would result in increasing consumer exposure to these compounds.

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Background and Objectives: Biosorption is a new and inexpensive technique in heavy metals removal and recovery from aqueous solutions. In order to evaluate the potential of this method for the removal of nickel ions, biosorption of nickel ions from aqueous solution was studied using Cystoseira indica biomass in a packed bed column. Materials and Methods: The uptake capacity of nickel ions was investigated using protonated biomass at different influent concentrations and flow rates. In addition, the experimental breakthrough curve obtained under definite experimental conditions was modeled using Thomas, Yoon & Nelson, Dose-Response, and Belter models. Results: It was found that increasing influent concentration from 58 to 100 mg/l led to the increase of driving force for mass transfer and uptake capacity raised from 55.84 to 95.69 mg/g. The investigation of flow rate effect showed when the process is intraparticle mass transfer controlled, a slower flow rate favors the sorption. In the case of external mass transfer control, a higher flow rate decreases the film resistance and leads to an increase in mass transfer. Modeling the experimental data revealed that the abovementioned models were suitable to predict the breakthrough curves, especially Dose-Response. Measurement of pH of the effluent solution indicated that ion exchange is one of the main mechanisms of nickel biosorption using this biosorbent. Conclusion: The results of this study are complementary of the batch equilibrium sorption experiments. Therefore, from process viewpoint, this biomass can be proposed in the sorption columns as a sorbent for nickel ions.

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Background and Objectives: Development of cosmetics industry has increased the affinity to use these products by people especially women for makeup and toilet. Due to the presence of metals such as lead and cadmium as preservative and colored element in these products, concentrations of these metals in sunscreen cosmetics, lipstick and hair color were determined. Materials and Methods: Different brands of cosmetics were analyzed to determine Cd and Pb concentration (in µg/kg dry weight) using graphite furnace atomic absorption (AA-670). Results: We found that generally mean concentration of Cd was lower than Pb. There was no significant difference of Cd level between different brands of sunscreen and lipstick (p>0.05), whereas, a significant difference of Pb between the brands studied was observed (p<0.05). No significant difference was obtained between concentration of Cd and Pb in various brands of hair color (p>0.05). Conclusion: Though levels of Pb and Cd in selected brands of cosmetics were lower than standard limits, their low concentration in compared with the results of previous research works could induce serious hazards on human health and the possibility of occurrence or exacerbation of disease including allergy, inflammation, skin diseases, cancer and so on. Hence, preparation and use of these products must be done according to current standards.

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Background and Objective: Various industries such as petrochemical, oil refinery, pharmaceutical, plastics, paper, steel and, resin produce a substantial of phenol and its derivatives. Wastewaters containing phenol need careful treatment before discharging into the environment due to their poor biodegradability and high toxicity. The objective of this study was to remove phenol by multiwall carbon nanotubes from aqueous solution. Materials and Methods: Adsorption process was implemented in a laboratory-scale batch with emphasis on the effect of various parameters such as contact time (5 to 120 minutes), pH (3- 11), initial concentration of phenol (5 - 50 mg/l) and the sulfate and chloride ions (20 - 200 mg/l) on adsorption process. To achieve a better realization of adsorption process, sorption kinetics and equilibrium isotherms were also determined. Results: The results indicated that maximum adsorption capacity occurred at concentration 50 mg/L and t =30 minutes. The uptake fluctuated very little in the pH range of 3–9, and at greater than 9 the absorption decreased suddenly. Moreover, the presence of sulfate and chloride ions had no effect on the process. It was found that adsorption kinetics and equilibrium data follow a pseudo-second-order kinetics model and a Freundlich isotherm model respectively. Conclusion: It is concluded that carbon nanotubes being effective in a wide range of pH, short time to reach equilibrium and the absence of competing ions on the absorption process can be used effectively in removing phenol from aqueous solution.

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Background and Objectives: Optimization of mazut biocracking with different variables is one of the bioengineering applications in petroleum industry. The purpose of this study was to optimize biocracking of mazut by native microorganisms. Materials and Methods: To optimize mazut cracking, using Taguchi method we run 32 experiments using seven factors including amount of microbial inoculation, initial pH, surfactant, glucose, phosphor source, nitrogen source and sea salt each of them with four levels and factor of microorganism type with two levels for design of experiment using that 32 experiments were designed by them. Results: Results showed that microbial mixture, 0.016 OD600 microbial inoculations, pH 8.3, Tween80 concentration of 2 g/L, glucose concentration of 4 g/L, phosphate concentration of 5 g/L, ammonium concentration of 9 g/L and sea salt concentration of 0.5 g/L were optimized conditions for biocracking of mazut process. Conclusion: Optimized level for each factor was not essentially inevitably the highest or the lowest level. Based on the analysis of variance, phosphor source with 15.8% and pH with 14.8% had the highest effect among other factors however overally, error factor with 31.6% had the highest influence. Amount of microbial inoculation with 0.63% had the lowest effect on optimizing biocracking of mazut.