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Background and Objectives: Staphylococcus aureus is an opportunistic pathogen that frequently leads to asymptomatic infections. Methicillin-resistant strains (MRSA) pose a significant threat as they are resistant to most commonly used antibiotics, complicating treatment efforts. This study aimed to develop chitosan nanogels loaded with vancomycin and IFN-γ and to assess the expression of the TNF-α gene in a cell line infected with MRSA. Materials and Methods: Following the synthesis and confirmation of the chitosan nanogels, vancomycin and IFN-γ were incorporated into these nanogels. The synthesis was validated using DLS, FTIR, TEM, and SEM. Subsequently, the antibacterial efficacy of the nanogels was assessed. Finally, four groups of cell lines were designed: control, MRSA, chitosan nanogels and IFN-γ-vancomycin chitosan nanogels. After infection of the groups (except control) with MRSA, 5 μg/mL of nanogels, and nanogels (drug and IFN-γ) were added to groups 3 and 4, respectively. Then the expression of TNF-α gene in each group was analyzed by RT-PCR at 6 and 24 hours. Results: At pH 6.5 and 7.4, the MIC of 1 μg/mL was obtained for free vancomycin, whereas that of IFN-γ-vancomycin nanogels at both pHs was respectively 8 and 64 μg/mL. The IC50 of chitosan nanogels and nanogels loaded with vancomycin-IFN-γ on RAW264.7 cells were 2.37 and 4.15 μg/mL in 24 hours, respectively. In group 4 in comparison to the MRSA group, TNF-α expression decreased significantly following 24 hours. Conclusion: Loading of vancomycin and IFN-γ in the chitosan nanogel can reduce TNF-α gene expression on MRSA infected cell lines.

Abstract Conventional wastewater treatment processes are often unable to remove antibiotics with resistant compounds and low biological degradation. The need for advanced and sustainable technologies to remove antibiotics from water sources seems essential. In this regard, the effectiveness of a spinning disc photocatalytic reactor (SDPR) equipped with a visible light-activated Fe3O4@SiO2-NH2@CuO/ZnO core–shell (FSNCZ CS) thin film photocatalyst was investigated for the decomposition of amoxicillin (AMX), a representative antibiotic. Various characterization techniques, such as TEM, FESEM, EDX, AFM, XRD, and UV–Vis-DRS, were employed to study the surface morphology, optoelectronic properties, and nanostructure of the FSNCZ CS. Key operating parameters such as irradiation time, pH, initial AMX concentration, rotational speed, and solution flow rate were fine-tuned for optimization. The results indicated that the highest AMX decomposition (98.7%) was attained under optimal conditions of 60 min of irradiation time, a rotational speed of 350 rpm, a solution flow rate of 0.9 L/min, pH of 5, and an initial AMX concentration of 20 mg/L. Moreover, during the 60 min irradiation time, more than 69.95% of chemical oxygen demand and 61.2% of total organic carbon were removed. After the photocatalytic decomposition of AMX, there is a substantial increase in the average oxidation state and carbon oxidation state in SDPR from 1.33 to 1.94 and 3.2, respectively. Active species tests confirmed that ·OH and ·O2 − played a dominant role in AMX decomposition. The developed SDPR, which incorporates a reusable and robust FSNCZ CS photocatalyst, demonstrates promising potential for the decomposition of organic compounds.

In recent years, the use of a horizontal spinning disc reactor (SDR) as a photocatalytic reactor for the degradation of various pollutants in aqueous solutions has increased. This study was searched based on the PRISMA method. Two autonomous researchers carried out for the relevant studies using Scopus, Web of Science (WOS), and Science Direct databases. The search terms expanded focusing on the performance of horizontal spinning disc photocatalytic reactor (SDPR). In this review article, the main objective of the effect of operational factors on the efficiency of the degradation of pollutants with changes in the type of light source (range of visible light and UV radiation), disc rotational speed, flow rate, initial concentration of pollutants, pH, type of disc structure and flow regime are considered. Current challenges in SDPR include issues such as limited mass transfer, uneven light distribution, and difficulties in scaling up. To overcome these challenges, improvements can be made by optimizing reactor design for better mass transfer, enhancing light distribution through advanced light sources or reactor configurations, and developing scalable models that maintain efficiency at larger scales. Additionally, the use of innovative materials and coatings could improve the overall performance of SDPR.

Abstract Background and objectives Due to an increased rate of inflammation in generalized anxiety disorder (GAD), insight into the mediating factors in the onset and recurrence of the inflammatory response can help to achieve novel treatments for alleviating the risk of GAD. In the current study, we aimed to evaluate the possible relationship between visceral adipose tissue (VAT) as an important intermediary in inflammation pathways and GAD in participants of the Employees’ Health Cohort Study of Iran (EHCSIR). Method We analyzed the data from 3889 included participants aged > 18 years in the EHCSIR study, which were collected from 2017 to 2020. Lifetime and 12-month GAD were assessed using the Composite International Diagnostic Interview (CIDI-2.1) questionnaire. The adjusted prevalence ratio was computed to evaluate the association between GAD and visceral adiposity index (VAI), GAD and visceral fat area (VFA), GAD and body mass index (BMI) and ultimately GAD and waist circumference (WC) in males and females using STATA software. Results Log-binomial analysis showed a higher prevalence ratio of 12-month GAD associated with VFA in women [PR: 1.42, CI: 1.07–1.87, P: 0.015]. The prevalence of lifetime GAD was higher in obese women (BM1 > 30) [PR: 2.35, CI: 1.07–5.13, P:0.03] than in women with normal BMI. Women with higher VAI were also significantly more likely to suffer lifetime GAD [PR: 1.25, CI: 1.05]. 1.48, P:0.01]. In males, the prevalence of lifetime diagnosed GAD per 1 standard deviation increase in VFA was 0.65 [CI: 0.46–0.91, P: 0.01]. Conclusion Visceral adiposity as a positive agent was associated with GAD prevalence in women. The presence of GAD symptoms showed no relationship to VFA in men.

Background: Antibiotics are among the environmental pollutants with stable effects during consumption, they are rarely completely metabolized in the body and 30-90% of them are excreted through urine and feces and enter into the environment. The present study was conducted to evaluate the degradation of cefixime pollutant by photocatalyst Fe3O4@SiO2@TiO2@rGO + UV in the presence of persulfate (PS) from synthetic wastewater. Methods: Fe3O4@SiO2@TiO2 (F@ST) photocatalyst was synthesized by co-precipitation method, and then fixed on reduced graphene oxide (rGO). The structural properties of magnetic photocatalyst were evaluated using FESEM, XRD, TEM, VSM techniques. The effect of variables such as solution pH, catalyst dosage, persulfate concentration and initial pollutant concentration on the performance of the FS@T/rGO/PS/UV process in the degradation of cefixime pollutant was investigated. After determining the optimal conditions, the influence of interfering ions and scavengers on the process, as well as the amount of recovery and reuse of the catalyst were investigated. Results: The synthesized photocatalyst had features such as excellent magnetic properties, crystalline and relatively spherical structure in nano size, high purity, photocatalytic properties in both ultraviolet and visible ranges. Under optimal conditions (pH=6.5-7, PS= 2mM and photocatalyst dosage= 0.1 g/L), after 60 min of oxidation time, cefixime antibiotic with a concentration of 50 mg/L and TOC, respectively, with efficiency > 98% and 55.7% were removed. The performance of the process was affected by the presence of organic scavengers (TBA, NaN3, KI and CH3OH) and interfering ions (Cl-, SO4-2, NO3- and CO3-2); so that the pollutant degradation efficiency decreased in the presence of organic scavengers and interfering ions. The effective reaction species were included h⁺, 1O2, OH• and SO4•⁻ in the degradation of cefixime by photocatalytic process in the presence of PS. The synthesized photocatalyst could be used for 4 consecutive steps, and in the fourth step, cefixime was degraded with an efficiency of 70.1%. The behavior of the photocatalytic degradation of cefixime antibiotic per unit time was a function of the pseudo-first-order kinetic model. Conclusion: : FS@T/rGO/UV/PS photocatalytic process with features such as high efficiency in antibiotic degradation, easy and fast separation, pollutant mineralization, production of side products with simple molecular structure and good performance on the real wastewater sample could be used as a suitable method for industrial wastewater post-treatment as well as pre-treatment in order to reduce organic load and increase biodegradability.

Bio-leaching is a non-invasive, relatively affordable and environmentally friendly method through which toxic compounds are decomposed with the help of microorganisms and with the help of enzymatic reactions. This study was conducted in order to use biological leaching in order to rehabilitate soil contaminated and resistant to biological decomposition by heavy metal lead and phenanthrene around the south Tehran oil refinery. The design of the experiment was done with the response surface method. In the bioleaching method, the purified strain (Pseudomonas aeruginosa) was isolated from the soil of the refinery. Environmental pH (3, 5, 7, 9, 11), pollutant to biomass ratio (7.50, 15, 22.50, 30, 37.5 mg/g) and retention time (1, 2, 3, 4, 5 hours) were considered as main variables. pH was the most important parameter influencing the removal of lead and phenanthrene from soil. The highest percentage of lead removal with 96.79% pH is equal to 8, pollutant ratio to Live current equal to 30 W/W and time 2 hours was obtained. In the case of phenanthrene, the highest percentage of phenanthrene removal (97.4%) in pH was equal to 7, the pollutant to living organism ratio was equal to 22.5 W/W and the time was measured for 1 hour. The results of this study showed that the use of bacteria increased the efficiency of the removal process compared to the cleaning process without bacteria (42% for phenanthrene and 67% for lead).

Abstract Environmental destruction, water crisis, and clean energy are among the very important challenges worldwide based on sustainable development goals. Photocatalytic fuel cell, a potential candidate for converting chemical energy into electrical energy through a pollution-free method, holds promise in addressing these challenges. In this regard, we investigated the response of a photoanode covered with UiO66-NH2-TiO2/NiF on a porous nickel foam as an attractive electrochemical response to remove antibiotics from aqueous solution and simultaneously produce electricity using a one-step hydrothermal synthesis. Nickel foam with its fine structure provides a suitable space for the interaction of light, catalyst, and efficient mass transfer of reactive molecules. It appears that it can be used as a competitive electrode in fuel cells. In order to investigate the properties of the photocatalyst, structural analyses including XRD, FESEM, FTIR, and UV–vis DRS were utilized. Additionally, polarization and electrochemical tests such as chronoamperometry and EIS were measured to further examine the electrochemical features of the PFC photoanode system. The obtained results under optimal conditions (SMZ concentration = 20 ppm, pH = 6, irradiation time = 120 min) were as follows: removal efficiency of 91.7%, Pmax = 16.98 μW/cm2, Jsc = 96.75 μA/cm2, Voc = 644 mV. The light-induced current flow in UiO66-NH2-TiO2/NiF exhibited prominent and reproducible photocurrent responses, indicating efficient and stable charge separation in TiO2/NiF composite materials, which is a promising strategy for pollutant removal and simultaneous electricity generation.

Residual pharmaceuticals in the environment are a class of emerging pollutants that endanger human health. Tetracycline's family, including oxytetracycline (OTC), are known as one of the most produced and consumed antibiotics worldwide. The g-C3N4/Fe3O4 nanocomposite with high level of catalytic efficiency features suitable performance in water/wastewater treatment. Therefore, in the present study, this nanocomposite was applied to remove the oxytetracycline from the aqueous environment. In this research study, g-C3N4/Fe3O4 nanocomposite (serving as catalyst) was initially synthesized by a simple hydrothermal method. The effect of key operating parameters such as initial solution pH, dose of catalyst, contact time and initial concentration of OTC in aqueous solutions was investigated under UV irradiation. In addition, COD and TOC tests, the kinetics and the effect of radical scavengers on the applied photocatalytic process were all evaluated. The maximum removal efficiency of OTC (99.8 %) was achieved under the following conditions: neutral solution pH 7; catalyst dose, 0.7 g/L; and an initial OTC concentration of 5 mg/L. The data showed that the kinetics of the reaction followed the first-order model with R2 of 0.9755. The respective COD and TOC efficiency values for the applied photocatalytic process were determined to be 87 and 59 %, respectively. In addition, the lowest removal efficiency of OTC was observed in the presence of tert-butanol radical scavengers, and OH radicals played a main role. The UV/g-C3N4/Fe3O4 photocatalytic process proved to be highly efficient for the removal of OTC antibiotic and could be potentially applied for the removal of other pollutants from aqueous solutions.

Abstract Antibiotics are resistant compounds with low biological degradation that generally cannot be removed by conventional wastewater treatment processes. The use of yolk-shell nanostructures in spinning disc photocatalytic reactor (SDPR) enhances the removal efficiency due to their high surface-to-volume ratio and increased interaction between catalyst particles and reactants. The purpose of this study is to investigate the SDPR equipped to Fe3O4@void@CuO/ZnO yolk-shell thin film nanostructure (FCZ YS) in the presence of visible light illumination in the photocatalytic degradation of amoxicillin (AMX) from aqueous solutions. Stober, co-precipitation, and self-transformation methods were used for the synthesis of FCZ YS thin film nanostructure and the physical and chemical characteristics of the catalyst were analyzed by XRD, VSM,, EDX, FESEM, TEM, AFM, BET, contact angle (CA), and DRS. Then, the effect of different parameters including pH (3–11), initial concentration of AMX (10–50 mg/L), flow rate (10–25 mL/s) and rotational speed (100–400 rpm) at different times in the photocatalytic degradation of AMX were studied. The obtained results indicated that the highest degradation efficiency of 97.6% and constant reaction rate of AMX were obtained under LED visible light illumination and optimal conditions of pH = 5, initial AMX concentration of 30 mg/L, solution flow rate of 15 mL/s, rotational speed of 300 rpm and illumination time of 80 min. The durability and reusability of the nanostructure were tested, that after 5 runs had a suitable degradation rate. Considering the appropriate efficiency of amoxicillin degradation by FCZ YS nanostructure, the use of Fe3O4@void@CuO/ZnO thin film in SDPR is suggested in water and wastewater treatment processes.

The systematic review conducted in this study aimed to investigate the effect of biological methods of slaughterhouse wastewater treatment (SWWT) on reducing carbonaceous pollution concentration in the effluent. The researchers performed a comprehensive search for relevant articles in databases such as Scopus, PubMed, Web of Science, and Embase, focusing on studies published up to January 2022. After screening the retrieved records, the researchers identified 71 relevant articles that contained data on the removal efficiency of carbonaceous pollutants in slaughterhouse wastewater. These pollutants included total chemical oxygen demand, chemical oxygen demand, soluble chemical oxygen demand, biochemical oxygen demand, five-day biochemical oxygen demand, organic material, soluble organic compounds, and total organic carbon. The results of the qualitative synthesis indicated that certain SWWT methods exhibited higher removal efficiencies for carbonaceous pollutants. These methods were characterized by long hydraulic retention times, the use of polymeric filter media, attached growth processes, and operation at maximum organic loading rates. It's important to note that specific details regarding the individual studies and their findings are not provided in the given information. However, the systematic review suggests that certain biological treatment methods can effectively reduce carbonaceous pollution concentrations in slaughterhouse wastewater.

Background and Objective: Pharmaceutical compounds can cause potential risks to aquatic and terrestrial organisms. So far, different methods have been used to eliminate these pollutants, photocatalytic processes are one of the most efficient processes to eliminate pharmaceutical compounds. In this study, the efficiency of a novel MOF-based nanocomposite, PMo/UiO-66 as a photocatalyst for amoxicillin degradation under visible light irradiation was evaluated. Materials and Methods: The study of the chemical decomposition of amoxicillin using the PMo/UiO-66 system was conducted at different stages. First, the PMo/UiO-66 MOF nanocomposite was synthesized using the solvothermal method, then the properties of the synthesized nanocomposite were investigated using XRD, FTIR, and SEM techniques. The effect of different operational parameters such as pH (3, 6, and 9), catalyst concentration (15, 20, 25, and 30 %w/w), initial concentrations of amoxicillin (20, 30, 40, and 50 mg/L) at different times on the removal efficiency was investigated. The reusability of the catalyst for four cycles was assessed. Results: The results showed that PMo/UiO-66 nanocomposite at pH 6, 25 %w/w nanocomposite concentration, and the amoxicillin concentration of 20 mg/L led to complete decomposition of amoxicillin after 120 min. The kinetic of amoxicillin removal followed the first-order model. Reusability tests showed that the photocatalytic efficiency of the synthesized catalyst was not substantially reduced after four cycles. Conclusion: The current study confirmed that the PMo/UiO-66 system has an appropriate efficiency for photocatalytic removal of amoxicillin under optimized test conditions.

Abstract In this study, toluene and ethylbenzene were degraded in the photocatalytic-proxone process using BiOI@NH2-MIL125(Ti)/Zeolite nanocomposite. The simultaneous presence of ozone and hydrogen peroxide is known as the proxone process. Nanocomposite Synthesis was carried out using the solvothermal method. Inlet airflow, ozone concentrations, H2O2 concentrations, relative humidity, and initial pollutants concentrations were studied. The nanocomposite was successfully synthesized based on FT-IR, BET, XRD, FESEM, EDS element mapping, UV–Vis spectra and TEM analysis. A flow rate of 0.1 L min−1, 0.3 mg min−1 of ozone, 150 ppm of hydrogen peroxide, 45% relative humidity, and 50 ppmv of pollutants were found to be optimal operating conditions. Both pollutants were degraded in excess of 95% under these conditions. For toluene and ethylbenzene, the synergistic of mechanisms effect coefficients were 1.56 and 1.76, respectively. It remained above 95% efficiency 7 times in the hybrid process and had good stability. Photocatalytic-proxone processes were evaluated for stability over 180 min. The remaining ozone levels in the process was insignificant (0.01 mg min−1). The CO2 and CO production in the photocatalytic-proxone process were 58.4, 5.7 ppm for toluene and 53.7, and 5.5 ppm for ethylbenzene respectively. Oxygen gas promoted and nitrogen gas had an inhibitory effect on the effective removal of pollutants. During the pollutants oxidation, various organic intermediates were identified.

Alkaline batteries are one of the most used types of household batteries. The annual consumption of billions of alkaline batteries produces battery wastes that are not recycled in most countries. In this study, alkaline battery waste management status was investigated by defining an economic model based on cost-benefit analysis. Scenarios for improving the current situation by combining battery waste reduction methods and developing battery waste recycling units were compared using this financial model. The results showed that 24 tons of solid wastes from three sizes of alkaline batteries were landfilled annually, which caused 4.52 tons of zinc to leak into the environment. The cost-benefit of zinc recovery from the alkaline batteries was estimated by 73.1 USD/kg. Based on this, the study estimates that the linear management of alkaline battery waste results in an annual financial potential loss of 198,832 USD. 30% reduction in battery wastes by replacement of rechargeable batteries and the development of battery waste processing units to 50% of the current potential will reduce the annual release of zinc to the environment by 0.9 tons and the annual net income will be equivalent to 131,229 USD. Changing the management of alkaline battery wastes from a linear economy to a material recovery cycle will have a positive financial balance in addition to reducing environmental damage.

Abstract This study investigated the recycling of freshly-smoked cigarette butts (FCBs) and unsmoked cigarette filters (UCFs) into a cellulose acetate (CA) membrane. The both samples were prepared by means of a combination of seven cigarette brands, and the phase inversion method was used to recycle each sample into a membrane using N-methyl-2-pyrrolidone. The efficiency of the prepared membranes for the removal of chromium, cadmium, and lead from an aqueous solution in a forward osmosis reactor was investigated. The results showed that the both membranes had a smooth surface and macrovoids. The flux of the prepared membranes from the UCFs and FCBs recycling were 14.8 and 13.2 LMH, respectively. The porosity and reverse salt of the UCFs membrane were 61% and 3.5 gMH, while those for FCBs membrane were 58% and 3.9 gMH. The observed metal removal efficiency of the both membranes was in the range of 85 to 90%. However, increasing the concentration of metals up to five times caused a slight decrease in the removal efficiency (less than 5%).

Background and Objective: Double-glazing is one of the methods of sound control. The use of materials other than gas inside double-glazing can develop sound transmission loss. The present study aims to make a double-glazing filled with A200 hydrogel at different ratios and measure the sound transmission loss. Materials and Methods: In the present study, 4 samples of double-glazing were made with water and A200 hydrogel. The mixing ratios of hydrogel with water were 1:20, 1:75, and 1: 150. The sound transmission loss of each sample was measured three times by AvaSina impedance tube using the sound pressure level through two microphones installed on both sides of the sample according to ISO 10534-1. Then, the results were analyzed by SPSS software (version 24) and repeated measures test. Results: According to the results, the highest amount of sound transmission loss was related to the water sample at 250 and 500 Hz and the A200-1:20 sample at 1000 and 2000 Hz. Meanwhile, the A200-1:75 sample had the lowest sound transmission loss at 250, 500, and 1000 Hz, and the water sample at 2000 Hz. Conclusion: The present study indicated that filling empty space of double-glazing with hydrogel increases transmission loss in high frequencies and decreases it in low frequencies compared to that of the water sample. Also, transmission loss of the air sample was found significantly different from all other samples except the A200-1:150 sample by comparing the water and hydrogel samples with the air sample as a control.

Introduction: Nitrophenol compounds are toxic compounds found in industrial wastewaters. 2,4-dinitrophenol is the most dangerous compound among phenolic compounds. The aim of this study was to evaluate the removal of 2,4-DNP from wastewater by microwaved dried sludge adsorbent. Materials and Methods: The results of 2,4-DNP removal were discontinuously obtained by the high performance liquid chromatography (HPLC) at a wavelength of 360 nm with various effective factors, such as contact time, pH, initial concentration of 2,4-DNP, and microwaved sludge dose. Finally, the results were analyzed using the kinetics and isotherm models. The equilibrium time was obtained 120 min. The maximum removal rate was obtained at pH 7. Results: The findings indicated that the removal efficiency increased by increasing the adsorbent dose and decreasing the 2,4-DNP concentration. It was revealed that the removal of 2,4-DNP by microwaved sludge was 86%. The correlation coefficient value of linear and non-linear regression showed that kinetic studies follow the pseudo-second order model and isotherm studies follow the Freundlich isotherm model. The adsorption method relied entirely on pH and affected the adsorbent area attributes, ionization rate, and Delete percentage. When the pH was high, there was competition for the adsorption sites between hydroxide ions (OH) and 2,4-DNP molecules. At first, the adsorption process was high speed and gradually reached a stable level, because after a while, the adsorption sites become saturated. Conclusion: As the absorbent dose increases, the efficiency of the adsorption process increases, because larger amounts of adsorbent cause higher adsorption places.

Abstract Contamination of water with bacteria is one of the main causes of waterborne diseases. The photocatalytic method on the basis of bacterial inactivation seems to be a suitable disinfectant due to the lack of by-products formation. Herein, g-C3N4/Fe3O4/Ag nanocomposite combined with UV-light irradiation was applied for the inactivation two well-known bacteria namely, E. coli and B. subtilis. The nanocomposite was prepared by a hydrothermal method, and subsequently it was characterized by XRD, FT-IR, SEM, EDX and PL analyses. The optimum conditions established for the inactivation of both bacteria were as follows: nanocomposite dosage 3 g/L and bacterial density of 103 CFU/mL. In the meantime, the efficient inactivation of E. coli and B. subtilis took 30 and 150 min, respectively. The results also revealed that inactivation rate dropped with an increase in the bacterial density. It is also pointed out that OH˚ was found out to be the main radical species involved in the inactivation process. Finally, the kinetic results indicated that the inactivation of E. coli and B. subtilis followed the Weibull model. It is concluded that C3N4/Fe3O4/Ag nanocomposite along with UV-light irradiation is highly effective in inactivating E. coli and B. subtilis bacteria in the aqueous solutions.

Here, a combined pretreatment oxidation process (O3/H2O2) was investigated to enhance the biodegradability of raw landfill leachate (RLL) and biomethane potential (BMP) in anaerobic reactors. The central composite design (CCD) and response surface methodology (RSM) were employed to optimize the operational parameters influencing on RLL bioavailability in O3/H2O2 process: pH, Oxygen Flow rate, Reaction Time, and H2O2 concentration. The findings revealed that the O3/H2O2 increased biodegradability index (BOD5/COD) of RLL from 0.41 to 0.68 under optimized condition (pH=8, Oxygen flow= 0.25 L.min−1, Reaction Time= 25 min, H2O2 concentration= 2.5 g.L−1). Furthermore, the effects of O3/H2O2 process on BMP of RLL were surveyed under mesophilic anaerobic reactors (Temperature: 37 ± 1 °C) in viewpoints of operational performance and methane yield in a batch mode for incubation period of 24 days. The results showed that O3/H2O2 process simultaneously improve the BMP by 2.99 times higher in a shorter lag-phase period (5 days) compared with control. The pretreatment O3/H2O2 and mesophilic anaerobic digestion process revealed a feasible and efficient method for enhance BMP of RLL.

In the present study, electrospun zeolitic imidazolate framework-8/poly(lactic acid) nanofibers were successfully synthesized and characterized as a potential nanosorbent for the pipette-tip micro-solid phase extraction of chlorpropham, pirimicarb, carbaryl, and methiocarb carbamate insecticides from environmental water samples. The extraction procedure was followed by gas chromatography/mass spectrometry separation and determination of the target analytes. All the effective parameters of the extraction procedure were optimized through the one variable at-a-time method. Thanks to the very simple extraction procedure as well as the application of electrospun nanofibers with high surface area, the four analytes were efficiently extracted with as lowest extraction times as practicable. Under the optimal conditions, the calibration plots of the analytes were obtained within broad linear dynamic ranges of 0.5 – 150 ng mL−1 for chlorpropham and pirimicarb plus 1.0 – 175 ng mL−1 for carbaryl and methiocarb, respectively. Besides, limits of detection as low as 0.2 and 0.15 ng mL−1 for chlorpropham and pirimicarb, respectively, as well as 0.5 ng mL−1 for carbaryl and methiocarb indicate the favorable sensitivity of the analytical procedure. The applicability of the developed method was evaluated by quantitative determination of the target analytes in four different environmental water samples. Relative recoveries higher than 88.0% shows the acceptable accuracy of the method in the quantitative determination of the four carbamate insecticides.

Background and purpose: Emerging pollutants such as antibiotics are resistant to biodegradation. The aim of this study was to compare the effect of photocatalytic and Ozonation photolysis on decomposition of Sulfonamide antibiotics (Sulfacetamide, Sulfathiazole, Sulfamethoxazole, and Sulfadiazine) in aquatic environments. Materials and methods: In this study, experiments were conducted discontinuously. The effect of some parameters, including pH, initial antibiotic concentration, ozone concentration, contact time, and concentration of TiO2 on degradation of Sulfonamide antibiotic was investigated. Characteristics of this catalyst were analyzed using FTIR, XRD, SEM, and EDX techniques. The concentrations of antibiotics were measured by an HPLC analyzer equipped with a UV detector at a wavelength of 270 nm. Results: The highest percentage of sulfonamide removal under optimal conditions (pH 5, initial concentration of antibiotics= 10 mg/l, ozone concentration= 0.22 g/h, and catalyst concentration= 1 g/l) were obtained by photocatalytic and photolysis processes (92.1% and 100%, respectively). Intermediate products produced under these conditions included acetic acid, butyric acid, and low molecular weight products. TOC removal efficiencies of sulfonamides by photocatalytic and ozonation photolys were 80% and 79.6%, respectively. Conclusion: The study showed that the rate of ozonation photolysis reaction in the removal of sulfonamides was 2.6 times faster than the photocatalytic process.

Phenanthrene as the hazardous PAHs-component are extensively detected in industrial wastewater. However, the impacts of bioelectrostimulation process on Phenanthrene degradation in aerobic reactors remained unclear. Here, a novel bioelectrostimulation process equipped with carbon cloth as electrodes was developed to investigate the removal efficiency of Phenanthrene and ATPase enzyme activity in the synthetic wastewater. The results obtained from the present study indicated that a complete Phenanthrene degradation (100%) can be achieved using microbial electrostimulation systems steel mesh coated with carbon cloth (MES-CC) as anode under optimal operational conditions (electrical current: 4 mA, HA concentration: 15 mg L−1) within 18 h. The conductive carbon cloth provides a biofilm carrier to easily transfer the electrons between electrodes and microbial communities. In addition, the highest ATPase enzyme activity (5176 U) was observed when the aerobic MES-CC reactors were operated with electrical current 4 mA. Furthermore, the COD removal efficiency in MES-CC increased from 49% to 96% when the C: N ratio decreased from 20 to 5. The highest value of Vmax in MES-CC for suspended and attached growth were determined to be 2.87 and 0.54 g COD g−1 biomass. Overall, the results demonstrated that MES equipped with carbon cloth and continuous electrical current mode has good potential for efficient Phenanthrene wastewater treatment.

Considering the importance of onions consumption in the household diet, controlling of heavy elements' concentration in foodstuffs is important to ensure the safety of an individual's health. This study aimed to evaluate the risk of heavy metals through onion consumption on human health. In this cross-sectional experimental study, 22 onion samples with varieties red, yellow, and white in the two autumn and winter seasons in 2020 were randomly collected from the different provinces of Kurdistan, Hamedan, and Kermanshah. The concentrations of heavy metals were evaluated with an atomic absorption spectrometer. The risks of human health were evaluated by the hazard quotient (HQ) and the obtained results were analyzed with one-way ANOVA and one sample t-test. The obtained findings demonstrated that all collected samples contained heavy metals. For example, the cadmium (Cd) concentration in onion samples in the province of West Azerbaijan, Kurdistan, Hormozgan, Isfahan, and Zanjan was 526.49, 274.49, 69.77, 67.39, 65.69 µg kg−1, respectively. While the standard specified in Iran for the concentration of Cd in onions is 50 μg kg−1. However, the rate of lead (Pb) contamination in samples collected from Isfahan, Hormozgan, Zanjan Khuzestan, Tehran (Varamin) was 296.50, 266.71, 261.49, 215.64, 106.19 µg kg−1, respectively, which less than maximum allowable limit recommended by WHO-FAO (300 µg kg−1). The HQ for non-cancerous diseases for Cd and Pb were 8.6 × 10−2 and 1.6 × 10−1, respectively, and the probability of carcinogenic risk for Pb (8.1 × 10−4) was at the level of acceptable. There is no concern about the non-carcinogenic diseases and carcinogenic risk of consuming heavy metals in onion. Therefore, for optimal management and prevention of further pollution, it is recommended to study the origin and determine the amounts of heavy metals for their potential contamination of foodstuffs from the region's soil, water, and dust.

The contamination of water by organic pollutant viz. 2,4 DNP compound is recognized as most common environmental concern due to their highly toxic nature, worldwide. Adsorption has attracted much attention as a new technique to remove these contaminants from water and wastewater. The purpose of this study was to introduce an inexpensive adsorbent, dried waste sludge, for removal of 2,4 DNP compound. Material & Methods: At first, sludge was dried at temperature 60 °C. Next, CaCl2 was used to improve adsorption capacity. The removal efficiency of 2,4 dinitrophenol were determined by HPLC at wavelength of 360 nm. In addition, the effects of influencing factors including pH, initial pollutant concentration, contact time, and adsorbent dose were examined. The equilibrium binding were described by Langmuir or Freundlich isotherms and kinetic models. Results: The results obtained from adsorption process indicated that was 60 min is the equilibrium time. The optimum pH for adsorption for both adsorbents was found to be 7. The optimum concentration of 2,4-DNP was found to be 10 ppm. The results obtained from the present research showed that the removal of the contaminant using modified sludge sorbent was increased from 40.4% to 77.9% when dosage increased from 0.1 to 1.5 g. Equilibrium adsorption data for 2,4 DNP were fitted by using Langmuir, Freundlich and Freundlich adsorption isotherms model, respectively. Also it has been found that adsorption kinetics can be described according to the Pseudo-second order model. Conclusion: According to results, chemically modified waste sludge showed reasonable adsorption capacity. Therefore, it and can be used as a native alternative to 2,4 DNP compound removal from aqueous environments.

Background: Ibuprofen is one of the most widely used non-steroidal anti-inflammatory drugs that enter the water resources through manufacturing plants and disposal of hospital effluents and even domestic wastewater. The aim of this study was to removal of ibuprofen using biodegradation process by Saccharomyces Cerevisiae yeast fixed on alginate substrate from aqueous solutions. Method: This research was an experimental-laboratory study. The effect of parameters including yeast concentration (0.1-0.3 g/100ml), Initial concentration of ibuprofen (50-350 mg/l), contact time (1-30 hours), initial pH (4-7) on the biodegradation of ibuprofen with stabilized yeast on alginate substrate was investigated. Experiments were designed and optimized using response surface methodology in Design Expert 7 software. Results: The findings of this study showed that the maximum removal of ibuprofen by fixed yeast on alginate at pH = 5.5, yeast concentration 0.2 (g /100ml), time 30 hours, and initial concentration of ibuprofen=50 mg/L was 93.5%. Conclusion: Based on the results of this study, it can be concluded that the fixed Saccharomyces cerevisiae is capable to biodegradation of ibuprofen at low cost and high efficiency and this cost-effective method can be used for the treatment of pharmaceutical wastewater.

Backgrounds and objectives: Today chr('39')s World is faced with the environmental problems associated with heavy metal contamination as one of the main issues of concern. Mercury, known as one of the most toxic heavy metals, has gained a lot of attention due to its sustainability and bioaccumulation in the food chain as well as having detrimental health problems such as kidney failure and gastrointestinal damages. This study is centered on the removal of Hg (II) ions from aqueous solutions using a magnetite/biosilica/sodium alginate nanocomposite as an efficient adsorbent. Materials and methods: Within this study, the magnetite/biosilica/sodium alginate nanocomposite was successfully synthesized via a co-precipitation method. The structure and morphology of the prepared adsorbent were confirmed by SEM, XRD and VSM analyses. The parameters affecting the adsorption process such as pH, contact time, adsorbent amount, temperature and initial concentration of Hg (II) ions were all evaluated. Findings: The optimum conditions obtained were as follows: pH 5, adsorbent dosage 0.2 g/L, contact time 80 min, temperature 45 °C. The results revealed that the removal efficiency dropped by increasing Hg(II) concentration. The adsorption of Hg (II) obeyed the Langmuir isotherm (R2 0.9998) and pseudo-second kinetic model (R2 0.9997). Additionally, the thermodynamic studies demonstrated that the adsorption process is of endothermic and spontaneous nature. Conclusions: All in all, the synthesized adsorbent was applied for the removal of Hg (II) ions from the aquatic environment. Ease of separation from the aqueous solution due to its magnetic properties as well as high level of Hg (II) recovery are amongst the unique feature of the adsorbent.

Background & Objectives: Ceftriaxone is an antibiotic which is extensively used to treat a number of various infections. It is mainly accumulated in water and sewage resulting in the environmental and health problems. This study is centered on the evaluation of the efficiency of a photocatalytic process using Fe3O4@SiO2@TiO2 in the removal of ceftriaxone from aqueous solutions. Methods: This research was based on an experimental-practical study. Fe3O4 @ SiO2 @ TiO2 was initially synthesized via a sol-gel method and characterized by SEM, XRD and EDX analyses. The effects of variables such as pH, catalyst concentration, ceftriaxone concentration, contact time, reusability tests (n=7) and degree of mineralization were separately assessed in a laboratory scale. The concentration of ceftriaxone was measured by HPLC at 240 nm. Results: Based on the results obtained, the highest process efficiency of 96.7% was obtained under the following optimal conditions: concentration of ceftriaxone 10 mg/L, pH=3, the catalyst dosage of 2 g/L and a time contact of 120 min. At the end of the process, the degree of mineralization was determined to be 83.7%. Additionally, the data regarding the reusability of the nanocatalyst demonstrated that a 5.2% loss in the removal efficiency was observed after 7 times of reuse. Finally, the results revealed that the removal process of ceftriaxone follows the first-order kinetic model. Conclusion: The results demonstrated that the photocatalytic process using the magnetic nanocatalyst (Fe3O4 @ SiO2 @ TiO2) could be effectively used for the removal of ceftriaxone from aqueous media.

Background: Organophosphates are one of the most common pesticides in the world. One of the most commonly used toxins in this group is malathion, which is classified by the EPA as Group III carcinogenic substances. Therefore, due to the high consumption of this pesticide and its pathogenicity, it should be eliminated in an appropriate manner. One of the elimination ways is the use of advanced oxidation processes. The aim of this study was to determine the photocatalytic removal of malathion pesticide by g-C3N4/Fe3O4/Ag nanocomposite. Method: In this study, g-C3N4/Fe3O4/Ag nanocomposites synthesized by hydrothermal method were used for photocatalytic removal of malathion. The variables studied were pH, nanocomposite dose, and contaminant concentration. Furthermore, the radical effects of ammonium oxalate, tert-butanol, and benzoquinone were analyzed on the experiment procedure. Results: The best removal efficiency of malathion at pH = 7, the dose of 0.5 g/l, and contaminant concentration 10 mg/l at 60 min was 100%. By increasing the catalyst dose up to 0.5 g/L, the efficiency increased. However, with increasing contaminant concentration, the removal efficiency decreased. Additionally, the removal efficiency of malathion in the presence of ammonium oxalate, tert-butanol, and benzoquinone radicals was 93.36%, 44.78%, and 90.71%, respectively, and the reaction kinetics followed the first equation with R2 = 0.9852. Conclusion: Therefore, g-C3N4/Fe3O4/Ag has a high potential for malathion removal moreover can be used to remove various pollutants from aqueous solutions.

Background & aim: The discharge of pharmaceutical effluent containing antibiotics into water resources is a great of concern associated with environmental pollution. In addition, conventional treatment systems are not capable of eliminating these antibiotics which commonly used in dealing with treatment of humans. Furthermore, over-consuming of antibiotics over the past few decades has forced researchers to find new techniques in order to deal with this environmental issues of great concern. In the present work, TiO2 was employed as a catalyst in the non-homogenous catalytic ozonation process for removal of Ceftazide antibiotics from synthetic sewage. Materials and Methods: This fundamental-practical study was conducted in a pilot scale. The magnetic TiO2 nano-sized particles were synthesized through a sol-gel method. The properties of magnetized titanium dioxide nanoparticles as catalyst were characterized using SEM, XRD and EDX. The effects of variables: pH, catalyst dose, reaction time, pollutant concentration on the performance of catalytic process were investigated. The residual concentration of Ceftazide was analyzed by a high performance liquid chromatography (HPLC). Results: The findings of present study indicated that the high removal efficiency of Ceftazide occurs in alkaline conditions and a direct relation was observed between removal efficiency and pH. The catalyst dose of 2 g/l was determined as optimum dosage and the Ceftazide removal efficiency was improved by decreasing the initial concentration as time proceeded. The results showed that the removal of Ceftazide by this catalytic process are fitted with the first-order model. Conclusion: The results show that the catalytic ozonation process with magnetized titanium dioxide nanoparticles has high efficiency for removal of Ceftazide from aqueous media. The catalytic ozonation process can be considered as an effective way to remove Ceftazide antibiotics from aqueous environment.

Reduction of matrix effect seems to be a great challenge for the development of a practical method in bioanalysis. In this regard, a simple and efficient DLLME procedure along with a back-extraction step (DLLME-BE) was developed for the preconcentration of four common non-steroidal anti-inflammatory drugs (NSAIDs) in various biological fluid samples. Briefly, the analytes of interest were initially transferred into the extraction solvent followed by the back-extraction into an immiscible basic methanol (as an acceptor phase) for further preconcentration and clean-up. The main purpose of the work is reducing the matrix effect and sensitive determination of target molecules in the complex matrices. Following on, the separation and determination of the analytes were carried out using GC–MS (in-port derivatization) and HPLC-DAD instrument. The influential parameters affecting the DLLME-BE method were evaluated in detail and the best extraction conditions were established. Under the optimum conditions, low method detection limits in the range of 0.1–1.0 and 0.1–6.0 µg L−1 were obtained for GC–MS and HPLC-DAD analysis, respectively. Additionally, fair intra-day precisions of 2.7–14.5 and 2.8–7.8% as well as inter-day precisions of 3.9–14.5 and 3.5–8.1% were achieved for the GC–MS and HPLC-DAD analysis, respectively. Finally, the method was successfully applied for the determination of four common NSAIDs in different biological fluid samples. Keywords: Dispersive liquid–liquid microextraction, Back-extraction, Non-steroidal anti-inflammatory drugs, Gas chromatography, High performance liquid chromatography

Background and Aims: Nowadays, soil pollution with total petroleum hydrocarbons (TPH) is one of the major environmental issues caused serious problems to human and other living organisms. One of the best and most reliable methods of bioremediation is the use of earthworms known as vermin-remediation. In this study, bioremediation of gasoline-contaminated soil using Eisenia Fetida, the mixture of activated sludge and compost was evaluated. Materials and Methods: In order to determine the efficiency of bioremediation to removal gasoline from contaminated soil, cow compost and urban sewage sludge with a weight ratio of 1: 0.35:0.25, was used. Experiments were carried out in 6 reactors with different concentrations of diesel (10 and 30 g / kg soil), a different number of Eisenia Fetida earthworm (10 and 20) at ambient temperature during 90 days. To compare the performance of biodegradation of gasoline using Eisenia Fetida earthworm, two control reactors that contained only contaminated soil with two ratios of gasoline, vermicompost and activated sludge, were used. The (TPH) decomposition rate was measured by GC-FID. Results of this study were analyzed by Minitab version 17 software. Results: Results indicated reactor No.3 has the best removal efficiency of light hydrocarbons during 90 days. the removal efficiency of average hydrocarbons was 70% and heavy hydrocarbons with the highest removal efficiency of 68% in reactor No. 4 with characteristics Soil polluted with 10 g / kg of soil + 20 number of Eisenia Fetida, With a significant difference of other reactors. Conclusion: Based on the results of this study, the degradability of hydrocarbons has increased significantly with the addition of organic modifying materials and the increase in the number of earthworms.

Background: Cr (VI) is a highly toxic and carcinogenic contaminant and that are used in the steel industry and other chemical industries such as the leather industry, pigment production, electroplating of metals and the production of anticorrosive compounds. Its waste enters the environment and subsequently enters the water and food sources. Therefore, in order to protect the environment as well as human health, it is necessary to remove this pollutant from the environment, including soil, using appropriate methods. Material and Methods: Chromium resistant bacteria were isolated from the chromium contaminated soil and adapted by serial culture in Cr (VI) concentrations of 50-400 mg/L and microorganism growth and Cr (VI) reduction were measured. Then the soil was artificially contaminated at the laboratory by Cr (VI) compound (CrO3) and Organic compounds were added to soil at the Specified amount. Finally, a separated bacterial mix was added to the soil to initiate the bioaugmentation process. Results: After 3 stages of sampling and data analysis, the results of the study showed that Cr (VI) reduction efficiency by the bacterial mix reduced decrease by Cr (VI) concentration increase. So, under similar conditions, the efficiency of Cr (VI) reduction of soil, at a concentration of 50 , 200 and 350 mg / l, is about 86%, 51% ,and 26% respectively .Organic compound adding also increase bioaugmentation efficiency. Conclusion: The results of this study showed that optimizing soil conditions could improve the biodegradation process, especially in low concentrations of contaminants.

Background: Aniline is a toxic compound characterized by high solubility in water (3.5 percent; 35000 mg/l) leading to increased presence risk of aniline in wastewater. The presence of this compound in the blood causes the formation of met hemoglobin and prevent oxygen uptake and plays a key role in chemical asphyxiation, moreover, it has been thought as a carcinogenic risk factor to humans. Therefore, this study aims to synthesizes chitosan graphene oxide and determine the usefulness of using this absorbent to remove aniline from aqueous solutions. Methods: Chitosan Graphene Oxide (CGO) which was prepared from graphite powder by adapting the procedure used by Hummer, doped with chitosan and the characterization of CGO were determined by Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Powder Diffraction (XRD). To optimize the conditions, parameters including adsorbent dosage (g / L 0/2, 0/4, 0/6, 0/8, 1, 1/25,1/5), pH (2, 4, 6, 8, 10), contact time (5, 15, 30, 45, 60, 90, 120 min) and aniline concentrations (mg/L 50, 100, 150, 200, 300) were evaluated in a total of 126 tests. Finally Chitosan Graphene Oxide was used for aniline removal from aqueous solutions. Results: The results of present study showed that with increase in contact time and absorbent dosage and with decrease in aniline concentration, removal efficiency tend to increase. PH=6, time=30min, absorbent dose=1 g/l and concentration of aniline=50 mg/l were obtained as optimum conditions. Under optimum condition (pH=6, time=30min, absorbent dose=1 g/l and concentration of aniline=50 mg/l) the highest efficiency of aniline removal is %93.14. The adsorption isotherm showed that absorption process correlates well with Langmuir adsorption isotherm (R2>0.9996). Reaction kinetics complies with Pseudo-second order model with correlation coefficient of (R2=0.9799). In the study of thermodynamics, negative values of ΔH0 and ΔG0 respectively illustrate that reactions are exothermic and spontaneous. Conclusion: chitosan graphene oxide composite has the ability to remove aniline effectively from aqueous solutions. And also it can be used as an efficient adsorbent for related aqueous solutions.

Benzene is one of the hazardous environmental pollutants which have harmful effects on human, animal and environmental health. the goal of this study was to synthesize a carbon/alumina aerogel with large surface area, which is easily recoverable and can be used as an adsorbent for benzene removal from the polluted air flow. The composite aerogel was dried at ambient temperature for 48 h and at 120 °C for 48 h in a sequential way. The characteristic properties of the composite aerogel were analyzed using Brunauer-Emmett-Teller (BET), Scanning Electron Microscopy (SEM), Barrett-Joyner-Halenda (BJH) method and energy-dispersive X-Ray (EDX) techniques. The findings of this study showed that, with increasing of the inlet flow rate from 0.2 l/min to 0.5 and 0.8 l/min, the breakthrough time decreased from 13 h to 7 and 3 h, respectively., Besides, the amount of adsorption capacity on aerogel nanocomposite decreased from 126.73 mg g−1 to 84.5 and 38 mgg−1 with increasing the inlet benzene concentration from 100 ppmv to 200 and 300 ppmv, respectively. In addition, the a carbon/alumina aerogel can be exploited for removing other pollutants from air and water.Recently, the adsorption process has attracted many research attentions for Benzene removal from different applications due to some inherent characteristics such as low-cost and high feasibility. • The results indicated that the synthesis of the composite aerogel have been successfully performed. • The composite aerogel was synthesized by combining Novollac with alumina, which had high surface area and suitable benzene adsorption ability. Method name: Benzene removal from flow gas by aerogel nanocomposite Carbon-Alumina (C/Al2O3), Keywords: Benzene adsorption, Aerogel, Carbon-Alumina, Nanocomposite

Background: Laccase enzyme is capable of oxidizing many resistant and non-biodegradable environmental pollutants, so it has been studied frequently in recent years and is widely used in biodegradation of contaminants. Despite its abundant applicability, due to its short life span, nonrecovery, thermal instability and instability in organic environments, its widespread use is very limited. The present study aimed to increase the stability of laccase by immobilizing it on silica coated iron oxide nanoparticles. Materials and Methods: Fe3O4 nanoparticles were synthesized based on the co-precipitation method and after coating with silica, their surface was modified by amine groups. The enzyme was then immobilized by covalent binding using glutaraldehyde. Specifications of synthesized nanoparticles and immobilized enzyme were investigated using X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), and Energy-dispersive X-ray spectroscopy (EDX). Results: Results of successful laccase immobilization on nanoparticles showed that laccase immobilization significantly increased storage and thermal stability, maintaining activity in a wider range of temperature and pH than free laccase. Conclusion: The immobilization of laccase on silica-coated iron oxide nanoparticles can reduce the barriers and challenges of various enzymes by increasing its efficiency and stability.

Introduction and purpose: Chlorophenol is known as one of the toxic and dangerous pollutants in industrial wastewaters that’s a essential to it’s removal from industrial wastewaters and ground waters. The aim of this study was to investigate the efficiency of 4-Chlorophenol (4-CP) degradation using Ultraviolet/Hydrogen Peroxide process (UV/H2O2). Methods: The variables of the present study included initial concentration of pollutant, contact time, pH, and H2O2 concentration on 4-Chlorophenol removal on a laboratory scale. The concentration of residual 4-Chlorophenol was determined using UV/Visible at a wavelength of 280nm. In addition, the amount of mineralization in optimal conditions was evaluated using the measurement of total organic carbon (TOC) removal range according to the standard method 5310- B. Synthetic models of the process were also investigated. Results: The optimum removal efficiency of 4-CP by UV/H2O2 process regarding the concentration of hydrogen peroxide was 580 mg/L. pH of 3 and initial 4-CP concentration was obtained as 380 mg/L, and the presence of UV rays with a wavelength of 254 nm during 30m contact was 84.92% . In addition, 84.69% of the TOC was removed under the optimal condition. Moreover ,it was found that the data followed the first-order synthetic models. Conclusion: Considering the growing use of UV radiation in water treatment processes and the considerable efficiency of UV/ H2O2 process in removing 4-CP, this method can be proposed for the elimination of 4-CP after performing cost-benefit analyses. It can be concluded that with regard to purification goals and standards for wastewater treatment, UV/ H2O2 process can be used as a pre or final treatment.

Lead is one of the heavy metals that have harmful effects on the human health and environment. In this study, a new magnetic/biosilica/sodium alginate adsorbent (MBSA) made by the coprecipitation method was used to remove lead from aqueous solutions. It was an experimental study conducted at laboratory scale. The properties of MBSA were analyzed by scanning electron microscope (SEM), XRD, and FTIR analyses. The influences of various parameters such as contact time (0–80 min), pH (3–11), initial lead concentration (10–80 mg/L), temperature (298–318 ºK), and adsorbent dosage (0.5–4 g/L) on the sorption process were investigated. The equilibrium isotherm and kinetic models were used to evaluate the fitness of the experimental data. The results showed that lead removal using MBSA was obtained at an optimum pH of 11, contact time of 80 minutes, adsorbent dosage of 4 g/L, lead concentration of 10 mg/L (46.29 g/g), and temperature of 318 ºK. Investigating the isotherm and kinetic equations showed that the experimental data of the lead adsorption process correlate with the Langmuir model (R2 = 973) and intraparticle diffusion kinetic model, respectively. The values of the thermodynamic parameters (ΔΗ°, ΔG°, ΔS°) indicated that the sorption of Pb (II) ions on MBSA was spontaneous and endothermic in nature. Due to the good removal efficiency, low cost of the process, and lack of production of harmful substances for the environment, this adsorbent can be used to remove lead from the industrial wastewater.

Background and purpose: Photocatalysis process with TiO2 is a well-known method for removal of pollutants from water. However, the small particle size of TiO2, and therefore difficulty in its separation after treatment impede its commercialization. The aim of this study was to synthetize the Fe3O4@SiO2@TiO2 magnetic nanoparticles (NPs) and evaluation of its efficiency in removal of metronidazole (MNZ) from aqueous solutions. Materials and methods: The NPs were synthetized via sol-gel method, and characterized using SEM, XRD, VSM, and BET analysis. Then, the effect of operational parameters, including catalyst dosage, pH, and initial concentration of MNZ on removal efficiency were examined. The order of reaction and kinetic model, as well as the reusability potential of the catalyst were all investigated in the optimum run. Finally, comparison was made between the adsorption, direct photolysis, application of commercial Degussa P25 TiO2 (p25), and Fe3O4@SiO2@TiO2 NPs. Results: The so-synthesized catalyst showed good superparamagnetic properties. The optimum conditions for the MNZ removal were pH=8, the catalyst dosage=1.5 g/L, and initial concentration of MNZ=40 mg/L under 180 min UV irradiation time. The kinetic study revealed that the photocatalytic degradation of MNZ followed the pseudo- first order (R2= 0.9912) and the Langmuir-Hinshelwood model (R2= 0.9976). Conclusion: According to the results, the Fe3O4@SiO2@TiO2 NPs were almost as effective as commercial catalyst Degussa P25 TiO2 in removal of MNZ (P> 0.05). Due to the simple separation with external magnetic field and reusability potential, Fe3O4@SiO2@TiO2 NPs can be considered as a suitable alternative for Degussa P25 TiO2.

Abstract In this study, modeling and degradation of diazinon from contaminated water by advanced oxidation process together with a new test for effluent bioassay using E. coli were investigated. The experiments were designed based on response surface methodology. Nanoparticles (NPs) were synthesized using the sol–gel method. The shape characteristics and specifications of elements in the nanoparticles were characterized using scanning electron microscope and energy dispersive X-ray, respectively. Diazinon was measured using high performance liquid chromatography device and by-products due to its decomposition were identified by gas chromatography-mass (GC–MS). In the present study, effluent bioassay tests were conducted by defining the rate of dehydrogenase enzyme reducing alamar blue method. According to statistical analyses (R2 = 0.986), the optimized values for pH, dose of NPs, and contact time were found to be 6.75, 775 mg/L, and 65 min, respectively. At these conditions, 96.06% of the diazinon was removed. Four main by-products, diazoxon, 7-methyl-3-octyne, 2-isopropyl-6-methyl-4pyrimidinol and diethyl phosphonate were detected. According to the alamar blue reducing (ABR) test, 50% effective concentration, no observed effect concentration, and 100% effective concentration (EC100) for the mortality rate of E. coli were obtained as 2.275, 0.839, and 4.430 mg/L, respectively. Based on the results obtained, it was found that mentioned process was high efficiency in removing diazinon, and also a significant relationship between toxicity assessment tests were obtained (P

Background and purpose: There are several methods for removing oil contaminations from the polluted environments. Bioremediation could be considered as one of the best and most practical methods in the removal of oil contaminations. The aim of this research was to determine the bioremediation efficiency for soils contaminated with diesel by the biological stimulation of bioreactors containing vermicompost and activated sludge. Materials and methods: In an experimental study, the soil samples were collected from an area which was free of any oil pollution and 5 reactors containing one kilogram of soil were contaminated with diesel at the mass concentration of 1%. Two reactors were mixed with vermicompost at 15% and 20% mass concentrations and two reactors were mixed with activated sludge at 5% and 10% mass concentrations. Additionally, one control reactor was used to control the process. The pH of the reactors was between 7.5 and 8 and the C:N:P ratio was 100:5:1. The amount of TPH was measured at seven retention times within three months with two repetitions. The total removal of petroleum hydrocarbons (TPHs) was evaluated by GC-FID device. Results: The highest removal efficiency of TPH (40.24%) was observed in bioreactors containing vermicompost at a 20% mass concentration. In this reactor, the highest percentage of removal was observed in lighter hydrocarbons (50.49%). In reactors containing activated sludge, the average percentage of TPH removal was 32% which was observed in the reactor containing the 10% concentration of sludge. In this reactor, the highest percentage of removal (44.86%) was also observed in lighter hydrocarbons. Conclusion: Vermicompost and activated sludge can be used in the bioremediation of soils contaminated with diesel. In current study, the performance of vermicompost was found to be more efficient. Also, the results showed that by increasing the concentration of biological modifiers, the removal rate would increase.

Background: According to the Qur’an, man is the servant and the successor of Allah, the representative of prosperity on earth, and has the responsibility for the universe. This approach will create a constructive human interaction with the environment. Environmental degradation is against the will of Allah. It originates from ignorance, human selfishness, passions, and evil temptations, manifest in greed, arrogance, and extravagance. If humans control these abnormal factors and follow Qur’an teachings, they will enjoy a healthy environment that is a universal right. This paper seeks to study the anthropological theory of the Qur’an and its role in reducing environmental degradation. Methods: Based on the descriptive-analytical design, we explored 70 verses of the Holy Qur’an in which the words samā’, ‘ard, mas’ūl, khalīfah, shaytān, and those are cognate with the Arabic verbs sa-khkha-ra, ha-ra-sa, sa-ra-fa, ki-ba-ra, ha-wā, ‘a-ba-da, and ‘a-ma-ra, as well as the related articles, books, and philological and exegetical sources. We investigated the Qur’an to find the effect of awareness and more attention of human beings to the dimensions of man’s creation to reduce environmental degradation. These issues will be discussed in two parts: 1) the anthropology and the dimensions of human creation in the Qur’an, and 2) the causes of environmental degradation. Results: This study showed that the survival of life and human enjoyment of a healthy environment depends on enough knowledge of oneself, seeking help from Allah, and following the Qur’anic guidelines. These facts effectively control internal and external causes of environmental degradation, including ignorance, egoism, selfishness, and evil temptations. These actions destroy the roots of greed, arrogance, and extravagance in human beings. For this reason, Allah demands humans to develop earth, care for and rescue it from any destruction, avoid extravagance, and observe justice. Conclusion: Meditating in the Qur’an, the man knows his creative dimensions and environmental degradation factors that are incompatible with nature and are rooted in some of the inner and outer dimensions of human personality. Hence, he will consciously enjoy sustainable development and maintaining a healthy environment. This behavior will then reduce anomalies in the environment on his part.

Background and purpose: Phenol is amongst the dangerous environmental pollutants with wide applications in today’s life and industry. Nanoparticles have recently received attention for decomposition of these organic compounds. The aim of this study was to evaluate the efficiency of silver doped titanium dioxide stabilized on concrete bed via photocatalytic process Ag-TiO2/UV in removal of phenol from synthetic wastewater. Materials and methods: In this experimental-applied study, the volume of sample was 1000 ml. Initial concentrations were 10, 20, 50, and 100 mg/l and the samples were separately investigated under the effect of UV radiation and Ag-TiO2. The experiment was then performed under both conditions simultaneously. The variables included pH, initial phenol concentration, storage time, and photocatalyst loading. Phenol analysis was carried out by direct light metering with 4-aminoantipyrine reagent at 500 nm wavelength spectrophotometer according to standard method D5530. We studied the pH in three ranges (5, 7, and 10) and photocatalyst in three regions (20, 60, and 80 g/m2). Results: Based on the results, the highest levels of phenol decomposition were achieved by initial concentrations of 10 and 20 mg/l in optimal pH (3) at 40 and 80 minutes (100%), and initial concentrations of 50 and 100 mg at 180 and 200 minutes retention time in optimal pH (65% and 50%, respectively). The optimal photocatalyst loading rate was 80 g/m2. Conclusion: This study showed that the Ag-TiO2 nanophotocatalyst stabilized on a concrete bed, is efficient in phenol decomposition in presence of UV light.

Background and purpose: Antibiotics are extensively used in treatment of diseases. Metronidazole is an antimicrobial agent and is a nitroimidazole derivative, which is widely used in treatment of infectious diseases caused by bacteria and protozoa. This compound is irrefrangible, toxic, carcinogenic, mutagenic, and has high solubility in water. Advanced oxidation process is an effective method for removal of metronidazole from aqueous solutions. The aim of this study was to evaluate the efficacy of advanced oxidation process based on persulfate (UV / Na2S2O8) to remove metronidazole from aqueous solutions. Materials and methods: In this research, the effect of some variables such as pH, persulfate concentration and contact time was studied by a UV-C lamp (16 watts). Also, the remaining concentration of metronidazole was measured by UV-Vis spectrophotometer Cecil model CE7400. Results: The optimum conditions in this study were obtained at pH=9، persulfate concentration of 0.7 mmol/l, and contact time of 30 min. The removal of metronidazole by advanced oxidation process based on persulfate (UV / Na2S2O8) followed the first-order kinetic model. Conclusion: Persulfate-based advanced oxidation process (UV/Na2S2O8) is an effective method for removal of metronidazole from aqueous solution. It is recommended as an effective and efficient process that could be used for purification of aqueous solutions.

Background &Objective: the advantage of choosing Household water treatment over tap water for drinking is based on the human health assurance of health risks with these devices. The Hazard Analysis Critical Control Points system (HACCP) is a framework that identifies and manages significant hazards at the source to point of use in the process of producing drinking water. This study can be aimed at introducing of HACCP systems as a model to identify the most important potential hazards and control these risks in the flow diagram of RO-based Household Water Treatment in Tehran. Methods: The possible hazards identified at each step of water production by household water treatment. According to the principle of Seven HACCP, Critical Control Point (CCP) is selected and determined critical limits, monitoring, and corrective action. Sampling water is taken from each critical control point. Physicochemical and microbiological parameters were measured by standard methods. Results: Results of CCP Risk assessment have confirmed that the parameters of pH, nitrate, total organic carbon, and total coliform and fecal coliform were in the critical limits for defined CCPs. While, the total hardness, fluoride, and HPC were in the critical limit only at the CCP1. Conclusion: The results showed that the HACCP system can be used to reduce the risks, increase the safety of the output water of the household water treatment. To this end, regular monitoring must be carried out in the specified period by the appropriate operator.

Abstract Contamination of water resources by acetamiprid pesticide is considered one of the main environmental problems. The aim of this study was the optimization of acetamiprid removal from aqueous solutions by TiO2/Fe3O4/SiO2 nanocomposite using the response surface methodology (RSM) with toxicity assessment by Pseudomonas aeruginosa BCRC. To obtain the optimum condition for acetamiprid degradation using RSM and central composite design (CCD). The magnetic TiO2/Fe3O4/SiO2 nanocomposite was synthesized using co-precipitation and sol–gel methods. The surface morphology of the nanocomposite and magnetic properties of the as-synthesized Fe3O4 nanoparticles were characterised by scanning electron microscope and vibrating sample magnetometer, respectively. In this study, toxicity assessment tests have been carried out by determining the activity of dehydrogenase enzyme reducing Resazurin (RR) and colony forming unit (CFU) methods. According to CCD, quadratic optimal model with R2 = 0.99 was used. By analysis of variance, the most effective values of each factor were determined in each experiment. According to the results, the most optimal conditions for removal efficiency of acetamiprid (pH = 7.5, contact time = 65 min, and dose of nanoparticle 550 mg/L) was obtained at 76.55%. Effect concentration (EC50) for RR and CFU test were 1.950 and 2.050 mg/L, respectively. Based on the results obtained from the model, predicted response values showed high congruence with actual response values. And, the model was suitable for the experiment’s design conditions.

Background and purpose: Paraquat (PQ) is a bipyridinium herbicide that is very soluble in water. This non-selective contact herbicide is widely used in agriculture for weed control. In addition to the environmental impact, paraquat affects the entire body, especially the respiratory system, central nervous system and lymph nodes. In this study degradation of paraquat was investigated using Fenton and Fenton like processes. Materials and methods: This research was an experimental study in laboratory scale batch reactor (1L). During these processes, the effects of pH, Fenton and Fenton like agent concentrations (Fe2 +, Fe3+and H2O2) and initial concentration of paraquat in the removal efficiency were studied. The residual PQ concentration and the amount of organic carbon removal were measured by HPLC (259nm) and TOC measurement device, respectively. Results: Fenton like and Fenton processes could remove 86.44% and 84.53% of paraquat under optimal condition (pH=3, H2O2=29.4 mM, Fe=0.9 mM, PQ=0.194 mM) in 120 minutes, respectively. The TOC removal in Fenton like and Fenton processes was 52.15% and 45%, respectively. The PQ removal by Fenton and Fenton like process followed a pseudo-first order reaction kinetic model. Conclusion: Fenton process showed better performance in removal of PQ than Fenton process. So, it can be used as an appropriate and a supplementary treatment process in removing PQ from aqueous solution or final purification in a longer reaction time.

Background: Nonmelanoma skin cancers are the most frequently occurring skin cancers. Vitamin A is involved in epithelial cell differentiation and may control skin tumor development. Vitamin E is a powerful lipophilic antioxidant that can quench and scavenge reactive oxygen species. However, there is little consistent evidence considering micronutrients and the development of basal cell carcinoma (BCC). Therefore, we aimed to investigate the possible difference between retinol and α-tocopherol in BCC patients and controls in Iranian population. Methods: This case-control study was conducted on adults with newly diagnosed BCC referred to Razi Hospital, Tehran, Iran in 2015. Serum and subcutaneous fat tissue retinol and α-tochopherol were measured by HPLC method. Results: Overall, serum retinol level was lower significantly in BCC patients (0.237±0.01 µg/ml) in comparison with control group (0.27±0.02 µg/ml, P-value: 0.038). However serum ɑ-tocopherol level was not significantly different between BCC patients (4.41±0.33 µg/ml) and control subjects (4.06±0.35 µg/ml, P-value=0.18). Subcutaneous adipose tissue retinol was lower significantly in BCC patients (38.60±3.30 ng/mg) compared with control group (54.78±3.49 ng/mg, P-value=0.002). Furthermore, results revealed lower subcutaneous adipose tissue ɑ-tocopherol in BCC patients (4.41±0.33 µg/ml) in comparison with control group (4.06±0.35 µg/ml, P-value=0.18). Conclusion: Skin tissue concentration of retinol and ɑ-tocopherol and serum retinol level was lower in BCC patients in comparison with control group but serum ɑ-tocopherol was not different between groups.

The aim of the data were to increase the treatment efficiency of pyrene from soil using Nano catalysts magnetite iron oxide (Fe3O4) and combined with electro kinetic. Soil provided with 100 mg/kg concentration and removal of pyrene done with EK-Fenton process. Nano catalyst was synthesized via a facile co-precipitation method and characterized by FTIR, XRD, SEM, EDX, VSM techniques. The effects of some operational parameters include catalyst dosage, pH, hydrogen peroxide concentration and the voltage were studied on the removal efficiency of pyrene. Results indicated the removal efficiency was obtained 87% under optimal conditions (pH = 3, Nano catalyst dosage= 1 g/l, H2O2=10 mM and voltage 30 V). Electrokinetic Fenton process can be as efficient and effective method for the removal of pyrene from contaminated soil using Nano Catalyst Fe3O4 introduced in optimal conditions. Keywords: EK-pseudo-Fenton process, Soil, Fe3O4 nanoparticle

Uranium separation and removal are important from environmental, public health, and strategic veiwpoints. Scientits have put great efforts to develop technologies for uranium removal and regeneration because of its important applications and beneficial uses. In this study, efforts have been made to synthesize a modified form of Fe3O4@SiO2 and benzamide uranium complexes that can be exploited to remove and adsorb uranium onto an adsorbent that can be recycled. In the first step, Fe3O4@SiO2 was synthesized and later modified with trimethoxysilane. The adsorbent was subsequently characterized by SEM and FTIR. In a second step, experiments were performed to determine optimum stirring speed, contact time, ion strength, and adsorbent reusability. Finally, the performance of the adsorbent was tested in samples of real wastewater. SEM and FTIR analyses confirmed the satisfactory synthesis and modification of Fe3O4@SiO2 Nps. Statistical analyses revealed that although contact time, ion strength, and stirring speed were effective in adsorbent performance, they only led to a removal enhancement of 5% and a decrease of only 17% with increasing RPM to 250 and the enhancement of ion strength to 1.5M. The highest U(VI) removal efficiency in the synthetic solution was found to be 97%, which reduced to 49% in real wastewater samples. It was concluded that the nano-composite C14/SiO2_Fe3O4 adsorbent with its magnetic core and resistant surface not only offers the possibility for easy separation of urnaium from solutions but is also reusable and is only slightly affected by changes in stirring speed or ion strength. It, therefore, has a good capability for use as a U(VI) adsorbent in wastewater treatment.

Background and Purpose: Parabens are a group of Para-hydroxy Benzoic acid alkyl esters which extensively used as preservative in personal care products. Parabens have been recently found in wastewater, rivers, soil and dust. Therefore, the purpose of this study aimed to Monitor the occurrence of parabens from selected wastewater treatment plants (Shahrak Ghods and south of Tehran) and evaluate the performance of different treatment methods for removing these compounds. Methods: In this study, the samples from influent and effluent were collected from Shahrak Ghods and South of Tehran wastewater treatment plant as Seasonal and Three samples per season. Concentration of Para-hydroxy Benzoic acid esters was determined by HPLC, CECIL, 4100 at 242 nm. Result: After sampling in the different seasons from the west and south treatment plants, two selective paraben concentrations (Methyl paraben and Ethyl paraben) were measured. The results showed that average concentration of Methyl paraben (MeP) and Ethyl paraben) EtP( respectively were 740.7 and 277.7 ng/L in the Influent and 179.3 and 45.8 ng/L in the effluent of Shahrak Ghods treatment plant. Also, the average concentration of MeP and EtP respectively were 835.3 and 295.3 ng/L in Influent and 132.8 and 29.7 ng/L in the effluent of South of Tehran treatment plant. In the next step, Risk assessment of effluent treatment plants discharging to environment with comparing the studies was done. According to the paraben concentration in the effluent of both treatment plants, discharge of effluent treatment plants whit selective contaminants, have little biological effects on ecosystems. Conclusions: The removal efficiency of Shahrak Ghods treatment plant in removing parabens, was lower than the South of Tehran. But the effluent quality of both treatment plant was less than the Effluent discharge standard. So both of treatment plant have appropriate performance to removal contaminants.

Background and objective: The chemical industries develepment causes discharge of synthetic chemical compounds such as organic esters and plasticizers into the environment. Phthalic acid esters (PAEs) are refractory, hazardous, and emerging compounds that they produce dysfunction in hormones and endocrine, reproductive problems and cancer. Also this compounds enter into the environment through industrial effluent and causing environmental problems. The purpose of this study was evaluating the the application of UV/ Na2S2O8 / Fe2+ for DMP removal from aqueous solution. Materials and Methods: In the present study, effects of variables including, pH, persulfate concentration, Fe2+ concentration and time were studied as laboratory scale in batch method. Residual concentrations of DMP were determined by HPLC at 254 nm. The impacts of in dependent parameters on DMP removal percent were evaluated with Multi simplex and the response level(box Behnken method). Results: In this study, pH = 11, persulfate concentration of 0.51 Mmol/L, Fe2+ concentration 0.08 Mmol/L for 90 minutes, as conditions were optimized. The results showed that the DMP removal by UV/ Na2S2O8 / Fe2+ process follows first order reaction. Conclusion: The obtained results showed that UV/ Na2S2O8 / Fe2+ process for removing DMP from aquatic environments, has high efficiency (98% removal under optimal conditions). According to the results of study, the UV/ Na2S2O8 / Fe2+ can be used as an effective method for removing DMP from the chemical industries.