رضا شکوهی

Amoxicillin antibiotic is one of the antibiotics which is used in medicine and veterinary medicine to treat bacterial infectious diseases. In this study, a special electrochemical cell design was used as it could integrate the process units and the operation units to reduce COD and amoxicillin antibiotic residues from the wastewater of Alimoradian Hospital. Also, to optimize the operational parameters, the central composite design of response surface methodology (RSM) was used.

This experimental study was conducted in two parts. In the first stage, synthetic wastewater was prepared from Amoxicillin antibiotics to investigate the effect of various parameters such as reaction time, initial antibiotic concentration, current density, and pH on the efficiency of the method. In the second stage, the efficiency of the method in removing the antibiotic and reducing COD from the actual wastewater of Alimoradian hospital was evaluated.

Using the RSM, the optimal conditions of the laboratory findings were determined as follows: reaction time = 30 min, pH = 7.5, current density = 2.31 mA/cm2, and initial concentration of amoxicillin = 54.66 mg/L. Under these conditions, the removal amount of amoxicillin was 90.56%. The results also showed that under optimal conditions, the removal rate of COD and TOC from synthetic wastewater is 65.5% and 44.5%, respectively, and in the effluent of Alimoradian hospital is 47.7% and 38%, respectively. The reason for this difference is probably due to the presence of some resistant compounds in the real wastewater.

This experimental study showed that the combined electrocoagulation process can be a more effective method in removing the amoxicillin antibiotic and COD from aqueous solutions and hospital wastewater.

In this paper, the variations of particles distribution function (DF) in a one-dimensional collisionless plasma expansion are studied. It is shown that, for the self-similar cases the initial Maxwellian distribution function of ions gradually converse to a δ-like one. So, the dynamic of the ions could be considered with fluid equations. On the other hand, for the effects of charge separation that occurs assuming the expansion of finite plasma, the process of plasma expansion imposes variations on electrons DF which causes it to change from Maxwellian to a non-Maxwellian one. In order to investigate the electrons DF at each moment, a particle simulation is used. In this simulation, the electrons dynamic is determined by Vlasov equation. Ions dynamic is given by fluids equations. Finally, it is indicated that, the higher energy tails of electrons DF in the main body of plasma are descended due to the motion of high energy electrons into vacuum and the electrons DF transforms to a super-Maxwellian DF. In the opposite side, at ion front zone which is the place of high energy electrons presence, electrons DF transform from Maxwellian to Lorentzian case with the high energy tails

Considering the importance of alkalinity in pH regulation and its buffering role, in this study, the effect of inlet wastewater alkalinity on the efficiency of the anaerobic unit of the wastewater treatment plant. Moreover, a superior chemical compound in providing alkalinity to wastewater was investigated.

This study was performed in the treatment plant to determine the relationship between input alkalinity and removal efficiencies of COD, BOD5 and TSS. In order to determine the optimal alkali material for superb anaerobic wastewater performance, four common chemical substances including, NaOH, Na2CO3, Ca(OH)2 and MgO were selected and examined using One Factor At Time (OFAT) test method.

According to the results maximum removal efficiencies were obtained 62, 66.6 and 71.2% for COD, BOD5 and TSS, respectively under alkaline condition of 1260 mg/L CaCO3. Furthemore, the optimal dose to supply one unit of alkalinity by Na2CO3, Ca(OH)2 and MgO were 0.53, 0.54 and 0.3 mg/L, respectively. These values were obtained 5 min contact time and mixing rate of 150 rpm. However, for NaOH the optimal dose supply was obtained 0.35 mg/L for 3 min contact time and mixing rate of 100 rpm.

In conclusion, the performance of anaerobic baffled reactor is highly related to the supply of influent alkalinity to the reactor. In addition, the use of MgO can be considered as a suitable alkaline substance to neutralize acidic wastewater and provide alkalinity for ABR system.

Expansion of one-dimensional collisionless plasma into vacuum is studied in absence of magnetic field. In this paper, expansions of plasmas containing initial Maxwellian and modified Lorentzian (r,q) velocity distributions and the effect of q and r parameters on expansion are investigated and then compared by use of simulation of kinetic theory equations. In this simulation code, the electrons dynamic is determined by Vlasov equation and the ions dynamic obeys fluid equations. It is shown that the plasmas containing different initial velocity distributions for the electrons will be expand with different velocities. The results show that in the cases which initial electron distribution has more energy, then the ions will have more velocity.

The release of dyestuff wastewaters produced in textile industry into receiving waters affects both human health and the environment. The aim of this study was to investigate the efficiency of a photocatalytic UV/persulfate process in removal of methylene blue and acid green 3 dyes from aqueous solutions.

The current study was an experimental study, in which the effects of the most important operating variables including pH (3,5,7,9,11), contact time (5, 10, 20, 50, 70, and 90 min), Na2S2O8 dose (0.1, 1, 3, and 5 mM/L) as well as acid green 3 and methylene blue concentrations (10, 25, 50, 75, 100, 200, and 500 mg/L) were investigated to determine the optimal condition for dye removal in a batch cylindrical photoreactor equipped with a 9-W UV-C lamp, in laboratory scale. The concentration of target dyes in aqueous solution was detected using UV/Vis spectrophotometer.

The results showed that, under the optimum condition for studied variables, i.e. pH 7, persulfate concentration 1 mM/L, initial dye concentration of 50 mg/L, and contact time of 20 min, the removal efficiency of acid green 3 and methylene blue were 93.91 and 95.44%, respectively. In addition, at the aforementioned condition, the removal rate of COD and TOC were 67.35 and 53.30 % for acid green 3 as well as 70.74 and 56.99 % for methylene blue, respectively. Experiments were carried out under optimal condition for real wastewater, in which the removal rates of MB and AG Dyes were 76.11 and 72.51%, respectively, indicating the effectiveness of developed method.

The findings showed that the integrated UV/S2O8 process is a promising method for removing the methylene blue and acid green 3 dyes from aqueous solutions and it can be applied as an effective alternative for treatment of dyes-containing solutoins in large-scale applications.

Consumption of dissolved oxygen by organic substances in water resources result in undesirable environment for living organisms. The aim of this study was to evaluate the efficiency of natural wastewater treatment systems and activated sludge for municipal wastewater treatment.

This one year-cross-sectional study was conducted on wastewater treatment plants in Kermanshah province. During the study, sampling of raw sewage and effluent of treatment plant was carried out and the efficiency of treatment plant was evaluated by measuring TSS, BOD5 and COD. All the sampling and testing procedures were adopted from the standard method.

The results showed that the annual average of BOD5 in effluent for Wetland, stabilization pond, extended aeration and conventional activated sludge was 55, 25, 21 and 23 mg/l respectively. Also the annual average was 143, 43, 40 and 40 mg/lfor COD, and 47, 101, 40 and 33 mg/l for TSS, respectively. For COD removal the conventional activated sludge (86.97%) and Wetland (61.6%) were the most efficient and least efficient systems. For BOD5 removal the stabilization pond (85.18%) and Wetland (72.01%) were the most efficient and least efficient systems. The BOD5 / COD ratio in influent were respectively 0.56, 0.62, 0.59 and 0.55 in these systems.

In all of the mentioned wastewater treatment systems, the effluent parameters comply with the Iran environmental protection agency standards and it can be reused or discharged to water bodies. Also it can be concluded that, for above-mentioned parameters the removal efficiency of natural systems was more than activated sludge.

Antibiotics are potentially harmful contaminants, which can cause harmful effects on environmental equilibrium of ecosystems and the food chain. The aim of this study was to investigate the removal of ceftriaxone antibiotic by Saccharomyces Cerevisiae biosorbent from aquatic environments.

This experimental study was conducted in a lab-scale batch reactor as discontinuous. The fungus strain was collected from the “Persian Type Culture Collection of Iran”. After activating fungus strain, the plates were placed in incubator for 7 to 10 days at 25°C. Fungus cultures were transferred to a potato dextrose agar medium (PDA) in the form of dry ice and subsequently cultivated in potato dextrose broth (PDB) medium. In order to determine the adsorption efficiency of ceftriaxone from aqueous solutions, the impact of variables effected on adsorption including pH, initial concentration of antibiotic, biosorbent dose, contact time and temperature were investigated. The physical, structural and surface properties of produced biosorbent were determined by FTIR, SEM and BET techniques. Also, thermodynamic parameters, adsorption isotherms and adsorption kinetics were studied. Ceftriaxone concentrations were measured by UV-Visible spectrophotometer in 276 nm wavelength.

The results showed that the maximum absorption of ceftriaxone was 78% at pH=6, the initial ceftriaxone concentration of 10 mg/L, the absorbent dose of 0.75 g, the contact time of 120 min and temperature of 25°C. The surface adsorption of Ceftriaxone on biosorbent was followed by Langmuir isotherm (R2=0.903), and kinetic processes were more correlated with the Pseudo-second order model (R2=0.961).

It can be concluded from present study that the biosorbent produced from baker's yeast can be used as an effective and inexpensive adsorbent for ceftriaxone removal from aqueous solutions.

Urinary tract infection is the second most common cause of infection in the human body. Among the causes of urinary tract infection, Escherichia coli is the most common bacteria causing the urinary tract infection in both genders (male and female). Therefore, the aim of this study was to determine the antibiotic resistance pattern of bacteria causing urinary tract infection in the urine culture samples of the Shahid Beheshti Hospital Laboratory in Hamadan during 2016-2017. This descriptive cross-sectional study was conducted based on a purposive sampling for 16 months from April 2016 to July 2017 in Shahid Beheshti Hospital, Hamadan. In this study, urine specimens were collected by Midstream Clean Sugar method and then cultured in two Blood Agar and EMB culture mediums using standard loop. The results showed that, out of 1400 urine samples from outpatients referring to Shahid Beheshti Hospital in Hamadan, 235 were positive, of which 105 cases (44.7%) were related to men and 130 cases (55.4%) were women. Escherichia coli isolated with 141 (60%) cases was the most common organisms. Most of Escherichia coli isolates (126 cases) were resistant to ciprofloxacin antibiotic and only 1 case of resistance to Carbenicillin was observed. In general, the results showed that the most common bacterial agent of urinary tract infection was Escherichia coli and the highest cases of this isolate were resistance to ciprofloxacin. In addition, the highest antibiotic susceptibility was related to Nitrofurantoin.

In this paper, the effects of initial temperature of ions on the expansion of a one-dimensional collisionles plasma into vacuum is studied using kinetic theory. The particle dynamics is determined by the Vlasov equation for the electrons and ions based on a simulation code. In this simulation code, the Vlasov equation is solved by the characteristics method. The initial temperature effects of ions with comparison of different temperature ratio ions per electrons (Ti/Te), is investigated in the simulation. The results show that, the increase in the temperature of the ions leads to the higher velocity of the ions which cause the proximity of ions to electrons and then the faster decrease of the electric field. In addition, due to the initial temperature of the ions, the rate of expansion of plasma will increase.

Due to increasing the water demand and the lack of its resources, the reuse of effluents is considered as a useful option in the water resources management. The aim of this study was to evaluate the possibility of the reuse of effluents from the extended aeration process in the wastewater treatment plant of the Bojnoord city for agricultural uses.
This is a descriptive-analytical study which performed in 2013 on the quality of effluents in the wastewater treatment plant of the Bojnoord city by measuring the parameters of Electrical Conductivity (EC), Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD), nitrogen, phosphorus, Total Suspended Solids (TSS), Total Dissolved Solids (TDS), Sodium Adsorption Ratio (SAR), sodium percentage, magnesium ions, potassium ions, calcium ions, sodium ions and chloride.
The results shown that, the removal efficacy of BOD and COD were 88% and 89%, respectively, and it was higher than 85 percent for TSS and VSS factors; thus, the average residual concentration of BOD, COD, TSS and phosphate in the outflow were 27, 61, 26 and 11.34 mg, respectively. The average values of pH and EC in treated effluent were obtained 7.45 and 1940 μs/cm, respectively. Moreover, the values of chloride and SAR for the effluent of the wastewater treatment plant of the Bojnoord were achieved 3.89 meq/L and 221 mg/L, respectively.
based on the results, it can be concluded that the effluents of the wastewater treatment plant of the Bojnoord city can be valuable for use in agriculture; but, due to the high concentration of chloride in treated effluent, it is recommended that this effluent used for semi-sensitive plants. Furthermore, this effluent is not suitable for feeding to groundwater and for discharging into the surface water and it is needed to advanced treatment based on the standards.

Introduction and Aims: Pharmaceutical pollutants in aqueous can cause a number of health problems for people and other creatures. In this study, a survey of Dexamethasone removal from synthetic aqueous solutions was investigated by using UV/S2O8 and UV/H2O2 methods.
This experimental study carried out at lab scale at a reactor with the batch flow. In this study, the parameters of time (5- 60 min), pH (3, 7 and 11), dose of S2O8 (0.1-7.5 mM), dose of H2O2 (0.1- 7.5 mM), and Dexamethasone concentration (5- 20 mg/L) were studied to specify their effects on Dexamethasone removal. Furthermore, the remaining concentration of dexamethasone was determined by spectrophotometer DR (model 5000) in the 241 nm wavelength.
Results showed that with the increasing amount of parameters of pH, retention time, and a dose of H2O2 and S2O8 and with decreasing parameter of dexamethasone concentration, removal efficiency raised. Removal efficiencies of dexamethasone in the optimum condition of time=40, pH=3 and dexamethasone concentration = 5 mM was obtained 47, 59, 82, 91, and 98 percent for UV/S2O8 concentrations of 0.1, 0.5, 1.5, 5, and 7.5 mM, and 19, 49, 61, 65, and 72 percent for UV/H2O2, respectively.
According to higher removal efficiencies of UV/S2O8 method than UV/H2O2, easier storage and moderate stability of S2O8 and also more oxidation ability of SO4- than OH°, it is better to apply UV/S2O8 method to degradation of dexamethasone.

Malathion known as one of the most used organophosphates, with contact, digestive, fumigants and non-systemic properties has detrimental effects on ones nervous system. Recently use of photocatalyctic processes has grown widely because of its desirable ability to remove organic pollutants. In this study efficiency of photocatalytic process with persulfate and hydrogen peroxide for the removal of malathion was studied.
this study was carried out in laboratory scale and in batch flow reactors of steel which the low-pressure mercury vapor lamps of 55 watts was placed in it. The influence of parameters such as pH(3-9), H2O2(1-8Mm/l), perslfate dose(0.01-0.05 gr/l), and malathion (1-60 mg/l) was investigated. The malathion concentration in solution has been determined with the HPLC.
the results of this study showed that the discussed process has high efficiency in compare with other done studies, so that in optimum conditions – pH=3, concentration of persulfate 0.03 gr, consumed hydrogen peroxide 3mM and initial concentration of malathion 30mg/l – this process after 30 and 60 minutes, removed respectively 99.94% of malathion and 88.31% of COD.
photocatalytic process with persulfate and hydrogen peroxide as one of the advanced oxidation process alternatives has a high potential in reducing pollution load of different industries, including manufacture of pesticides and can be effective as a method for wastewater treatment and reduce the environmental problems.

Due to their polycyclic and toxic structure, dyes have a high ability in causing adverse acute and chronic effects on human exposed to them. In present study, the decolorization of acid green3 from aqueous solution by UV/ H2O2 method was investigated
This is an applied-experimental study. Parameters of pH in the amount of 3,7 and 11, contact time in 5,15, 30, 45 and 60 min, dose of H2O2 in 10, 30 and 50 mg/l and initial concentration of acid green3 in 50, 100 and 150 mg/l were examined to reveal the optimum amounts of these parameters. In order to emit the UV radiation, photo reactor with a 2-lit volume was applied, also to measure remaining concentration of dye, spectrophotometer device, model DR 5000 was employed. Chemical oxygen demand (COD) test based on 5220C method (standard method book) was used for determining amount of oxidation.
Results showed that contact time = 60 min, pH=7, acid green concentration=50 mg/l and dose of H2O2 =30 mg/l are optimum condition at which the removal amounts of dye and COD were obtained about 97 and 85%, respectively.
In the study, it is observed that parameters of contact time, pH, initial concentration of dye, and dose of H2O2 have a significant influence on the removal of the dye by UV/H2O2 process. Due to acceptable results of UV/H2O2 in the oxidation of the dye and the reduction of COD, this method can be introduced as reliable process to remove of acid green 3 from industrial wastewaters.

Dyes are one of the most important pollutants in textile wastewater, which are often carcinogenic, mutagenic and non-biodegradable, so it is important to remove them from the wastewater in terms of the environment. Therefore, the purpose of this study is to evaluate the efficiency of the compilative process of US/S2O8-2 in Eosin Y Dye removal from Aqueous Solutions. In this experimental study, it was possible to remove Eosin Y dye using ultrasonic waves alone and with persulfate oxidants. All reactions were performed in a 1000 ml cell of the ultrasonic bath. The effects of different parameters such as molar persulfate concentration (0.005-0.001 mol/l), dye concentration (100-100 mg/l) and pH (11-11) were investigated. To measure Eosin Y dye, UV/Vis-DR 5000 spectrophotometer was used at 515 nm wavelength. The results of this study showed that by increasing the oxidant concentration, the removal efficiency increased significantly, then a steady trend was observed in removing Eosin Y dye. The process used (US/S2O8-2) at pH=3, the persulfate concentration of 0.200 mol/l, and the time of 60 min had the highest removal efficiency (99.03%). Ultrasonic alone had little effect on the removal of this dye. The results of the effect of ion changes from calcium chloride on the performance of the process of US/S2O8-2 were ineffective for Eosin Y dye. Finally, the kinetic results showed that the US/S2O8-2 process followed a first-order reaction. The results of the use of the US/S2O8-2 process in the removal of Eosin Y dye indicated that this process has the proper ability to remove dyes and can be used as an effective method to remove Eosin Y from industrial wastewaters.

Petrochemical wastewater contains some kinds of toxic substances but if the effluent is treated properly, its reuse will be possible. This study aimed to evaluate the efficiency of wastewater treatment of Shazand Petrochemical Corporation and feasibility of its effluent reuse in green space irrigation and cooling towers.
In this descriptive study, the results of tests conducted by the laboratory of Shazand Petrochemical Corporation in 2016 were evaluated and analyzed, and then the feasibility of its effluent reuse in irrigation of green spaces and cooling towers was investigated. So the amount of chemical oxygen demand (COD), total suspended solid (TSS), Fecal Coliform, Total Coliform, turbidity and free chlorine in effluent of pond chlorination and also the amount of silica, alkalinity, calcium hardness, sulphate, COD, electrical conductivity and iron in the effluent of reverse electrodialysis unit were measured.
The results showed the maximum efficiency of wastewater treatment in the removal of COD was 98 percent. The amount of parameters in the effluent of chlorination pond was in accordance with the environmental standards for irrigation of green spaces and treated wastewater in the electrodialysis unit that with having maximum 0.12 mg/L iron, 126 mg/L sulfate ,and electrical conductivity 695 ϻs/cm was suitable for use in cooling towers.
The results of this study demonstrate that the effluent of chlorination pond can be used for irrigation of green space and also the treated wastewater in reverse electrodialysis unit can be used in cooling towers.

Polyvinyl alcohol is a persistent and water-resistant compound found in effluent of many industries and can be harmful to human health. Its presence in water supplies may cause problems in the process of settlings and removing heavy metals. This study aimed to determine the efficiency of Mn3O4 / H2O2 process to remove PVA.
This laboratory-scale research done to study the effects variables influencing process of Mn3O4/H2O2 including pH, hydrogen peroxide concentration, concentration of Mn3O4 nanoparticle, reaction time and concentration of PVA. To determine structural characteristics of nanoparticles XRD, BET SEM, and FTIR analyzes were used. Maximum absorption of contaminant by spectrophotometer was determined at 690 nm and the concentrations of PVA were determined by calibration curve.
BET analysis showed size of 19 nm for nanoparticles. Laboratory results showed that removal efficiency for Mn3O4/H2O2 process is 67.98% at; pH=3, Mn3O4 concentration= 0.4 g/l, concentration of hydrogen peroxide=20 mmol/l, reaction time=120 minutes, initial concentration PVA=100 mg/l. Removal efficiency decreased by increasing initial concentration of PVA and maximum efficiency of 71% observed for Mn3O4/H2O2 processes at initial concentration of 25 mg/l. UV radiation increased the efficiency of the process to 100% after 40 minutes.
In accordance with the results hydrogen peroxide activated by Mn3O4 catalyst is a suitable option for pre-treatment of waste water containing polyvinyl alcohol.

Nitrophenols are among the most common and toxic compounds in industrial effluents that 2, 4 dinitrophenol (2, 4-DNP) is the most toxic compound in this group. The object of this study was to optimize the removal of 2, 4-DNP by thermally activated persulfate using a central composite design.
This study was performed on a batch thermal reactor with a volume of 4 L. In this study, a central composite design (CCD) with RSM method was used for designing and optimizing the operation parameters such as initial pH of solution, potassium persulfate concentration and temperature. The effect of 2, 4-DNP concentration and reaction time at optimum conditions were also investigated.
The results indicated that the degradation rate of 2, 4-DNP was enhanced by increasing the concentration of persulfate and reducing temperature and pH. The optimum conditions for the highest degradation efficiency (99%) were as initial concentration 10 mg/L, reaction time 30 min, temperature 60 °C, Potassium persulfate concentration 10 mmol/L, and pH 5. At the optimum conditions, when 2, 4-DNP concentration was increased to 50 mg /L, the 2, 4-DNP degradation rate decreased to 73%.
This study indicated that the heat-activated PS oxidation could be an efficient approach for decomposition of 2, 4-DNP. Temperature was the most influential variable in this regard (P-value

Cadmium is considered as one of the most hazardous heavy metals, a non-essential, non-beneficial and highly toxic element to people. In the current study, the ability of aspergillus terreus fungi biomass was surveyed in the removal of cadmium from aquatic solutions.
This cross-sectional study was carried out in 2015 using fungal biomass culture on a shake flask. The dead biomass of aspergillus terreus fungi was applied as an adsorbent for the treatment of aquatic solution under the conditions of cadmium concentrations: 20, 40, 60, 80, 100 and 120 mgþ/l, pH: 3, 5, 7 and 9, retention time: 15, 30, 45, 60, 90, and 120 min and adsorbent dose: 0.1, 0.2, 0.5, 1 and 2 g. The remained concentrations of cadmium after adsorption were determined by atomic absorption spectrophotometer.
Results indicated that under condition of retention time: 90 min, pH: 7, initial cadmium concentration: 20mgþ/l and adsorbent dose: 1g, the biomass had a removal efficiency of 94%. Moreover, Adsorption process fitted to Freundlich isotherm with R2=0.9463 and first order kinetic with R2=0.9935.
In current study, it was observed that the factors of pH, retention time, dose of aspergillus terreus fungi and initial cadmium concentration had a noticeable effect on the adsorption amount. with regard to the high adsorption capacity of the biomass in comparison to other adsorbents in the removal of cadmium, this biomass can be used as a good adsorbent in wastewater treatment.

Chromium (VI) is one of the very toxic heavy metals and is known as a carcinogenic, mutagenic and teratogenic agent. In this study, the ability of dead Aspergillus Terreus fungus biomass in the removal of chromium (VI) from aqueous solutions was investigated.
The suspension of AspergillusTerreus was cultivated in Potato Dextrose Agar and Potato Dextrose Broth mediums. The biomass was then boiled in 0.5 N NaOH solution. The ability of obtained biomass to absorb Chromium (VI) was studied with respect to various variables including time (15 to 120 min), pH (3 to 11), chromium (VI) concentration (20 to 120 mg/L) and absorbent dosage (0.1 to 0.8 g). Chromium concentration was determined using an atomic absorption of. All ethical issues and citations were taken into consideration in conducting the study.
Results showed that the maximum removal of chromium (89%) was obtained at contact time 90 min, pH=7, chromium concentration 20 mg/L and adsorbent dosage 0.6 g. The adsorption isotherm was best fitted by Freundlich with a high correlation coefficient (R2=0.952). Furthermore, the adsorption kinetics fitted well to the pseudo-first-order model with a correlation coefficient of 0.9775.
The results of present study indicated that the studied variables have an incredible effect on sorption efficiency, as in the optimum condition, the biomass of AspergillusTerreus obtained an acceptable efficiency and adoration capacity compared to other adsorbents. So, this compound can be introduced as a practical natural adsorbent for chromium removal and also other heavy metals form aqueous solutions.

Organic compounds are one of the most important quality characteristics in wastewater treatment. The aim of this study is to make comparison of the efficiency of wetland and extended aeration activated sludge in the removal of organic compounds from sanitary wastewater based on response surface methodology.
In this experimental study 100 mixed samples were taken from wetland and extended aeration reactors. According to type of wastewater treatment and operating time, COD, BOD5 and TSS were measured. Sampling, transportation, storage and measurement performed according to standard methods. Experiment setting, modeling, removal equation of organic compounds and optimal condition was obtained by response surface methodology.
Maximum removal of COD, BOD5 and TSS (in summer) in wetland were 95.67, 93.4 and 87.41%; in extended aeration was 97, 65.1 and 80.2%, respectively. Efficiency of extended aeration was better than wetland in all seasons and all parameters. R2: 0.8- 0.89 confirms the effect of operating time on wastewater treatment efficiency. Validity and accuracy in wetland and extended aeration were 12.64-17.65 and 16.01-19.37, respectively. Removal model in both wetland and extended aeration was linear.
Efficiency of extended aeration is more than wetland. Response surface methodology properly describes organic compound removal efficacy by extended aeration and wetland.

Background and Bisphenol A is an estrogenic substance that can cause endocrine dysfunction, which extensively enters water resources due to its large use in industry. The aim of this study was to synthesis modified magnetic nanoparticles with sodium alginate and study of its efficiency for removal of Bisphenol A from aqueous solutions using heterogeneous fenton process.
In present study, sodium alginate magnetic beads were synthesized by nanotechnology and chemical precipitation method and the removal of Bisphenol A was evaluated in a pilot-scale batch reactor. In addition, the effect of environmental factors, including pH, reaction time, catalyst dosage, initial concentration of Bisphenol A, and the concentration of H2O2 on removal efficiency of Bisphenol A was studied. The concentration of Bisphenol A in samples was measured by spectrophotometry instrument and the XRD method was applied to identify the characteristics of modified nanoparticles.
In this study synthesized modified magnetic nanoparticles with sodium alginate had complete magnetism properties, and XRD analysis confirmed the presence of Fe3O4. The results showed that the highest removal efficiency of Bisphenol A was obtained at pH=5, reaction time= 120 min, catalyst dose= 5 g/L, and initial concentration= 20 mg/L which was about 95%.
According to our results, the magnetic nanoparticles modified with sodium alginate in a heterogeneous Fenton oxidation process are highly efficient in removing Bisphenol A.

Background and Using catalysts to enhance the efficiency of the ozonation process (known as catalytic ozonation process) has received much attention in recent years. This study aimed at examining the overall feasibility of using catalysts ozone as catalyst in ozonation process for decolorization and mineralization of a real textile wastewater in presence of persulfate.
This experimental study was conducted on a laboratory scale reactor using a semi-batch mode. The effect of persulfate, ozone flow rate, reaction time and catalytic dose in dye and COD was investigated in an optimal state of textile wastewater. To obtain optimization test, the experiment was performed by fractional factorial method at three-level factorial (3k−p) with a high resolution (VI).
In this study, 15 min contact time (P = 0.006) and 0.5g/L dose of catalyst (P=0.029) had the best effect on color removal. Moreover, the interaction of these parameters were found to be significant (P= 0.025). The optimum condition for color removal was achieved at 15 min reaction time, ozone flow rate of 2 L/min, 1.5 mM persulfate and catalyst dosage of 0.5 g/L. Optimum efficiency removal for color and COD in textile wastewater were 96% and 75%, respectively.
Application of nano-magnesium oxide with ozone in presence of persulfate showed synergistic effect and buffering property in decolorization and mineralization of textile wastewater. It also increases the efficacy of color removal and improves mineralization so, there would be no need for pH adjustment.

Expansion of one dimensional collisionless plasma into vacuum is studied under different initial ions temperature. In this study, a simulation code is used, in which the electrons dynamic is determined by Vlasov equation and the ions dynamic is determined by fluids equations. Finally, the effect of initial ions temperature on the expansion of plasma into vacuum is investigated and the obtained results are compared with self-similar solutions associated with plasma expansion including thermal ions. It is shown that in the area behind the ion front, in which quasi-neutrality conditions exists, the self-similar solutions coincide with the simulation results.

Background Endocrine-Disrupting Compounds are emerging group of trace contaminants detected in wastewater and water resources worldwide. Bisphenol A (BPA) is one of the compounds that can cause serious health problems.
Materials and Methods In this study, the removal of BPA from aqueous solutions by multi-walled carbon nanotubes was investigated. Experiments were performed in batch reactor and changing effective factors such as pH, contact time, concentration of carbon nanotubes, and concentration of BPA. The concentrations of BPA were measured using UV-VIS spectrophotometer at wavelength of 280 nm.
Results The results showed that maximum removal efficiency was 95% at a concentration of 400 mg/L of carbon nanotubes, pH=7, retention time of 60 minutes and BPA concentration of 20 mg/L. The maximum adsorption capacity was found to be 111.6 mg/g and the adsorption data were best fitted to the Freundlich isotherms and pseudo-second order.
Conclusion The results showed that carbon nanotubes have a high ability to adsorb BPA in the aquatic environment and can be used as a suitable adsorbent from aqueous solution.

Ciprofloxacin is an antibiotic vastly administrered for the treatment of infections. A major paortion of the drug remains non-metabolized and is excreted to find its way ultimately into water environments through discharge into wastewater. Although carbon nanotubes have been widely employed for the removal of contaminants, ciprofloxacin still poses problems against its proper removal. It is the objective of the present study to synthesize magnetite Fe3O4/MWCNTs and to evaluate its performance in ciprofloxacin removal via the heterogeneous Fenton process. For this purpose, the performance of the synthesized nanocomposite was evaluated while the effects of the following parameters were also investigated on the heterogenous Fenton process under lab conditions: pH, 4‒10); adsorbent quantity, 1‒3 g/l; initial antibiotic concentration, 30‒200 mg/l; contact time, 15‒300 min; and H2O2 concentration, 5‒25 μmol/l. Moreover, the synthesized Fe3O4/MWCNTs was morphologically and microstructurally characterized using Transmission Electron Microscopy (TEM) and X-ray diffraction (XRD) while the formation of carboxylic functional groups was verified by Fourier transform infrared spectra (FT-IR). It was found that the efficiency of the heterogeneous Fenton process for the removal of ciprofloxacin at a concentration of 30 mg/l was 95% in approximately 180 minutes and a molar ratio of 1 ml H2O2/2g Fe. Based on the results obtained, the Fe3O4/MWCNTs magnetite nanocomposite is well capable of removing ciprofloxacin from aqueous solutions in the heterogeneous Fenton process.