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This study was aimed to assess the leachate properties of the treated municipal solid waste by potassium carbonate (K2CO3) obtained from a landfill located in Barmshour, Iran. Consequently, two bioreactors were filled with the same waste in the laboratory. Potassium carbonate was added to one of the reactors and then both bioreactors were cured under the same conditions for 6 months. The physico-chemical properties of the produced leachate such as the volume, pH, COD, BOD, metals and non-metal ion concentration were measured at different time intervals. Results indicated that the applied K2CO3 initially increased the leachate volume; however, it decreased the volume of leachate by 72.7% after 6 months. The pH of the control sample observed to be acidic (

Antibiotics are considered among the most non-biodegradable environmental contaminants due to their genetic resistance. Considering the importance of antibiotics removal, this study was aimed at multi-objective modeling and optimization of the Fenton-like process, homogeneous at initial circumneutral pH. Two main issues, including maximizing Ciprofloxacin (CIP) removal and minimizing sludge to iron ratio (SIR), were modeled by comparing central composite design (CCD) based on Response Surface Methodology (RSM) and hybrid Artificial Neural Network-Genetic Algorithm (ANN-GA). Results of simultaneous optimization using ethylene diamine tetraacetic acid (EDTA) revealed that at pH ≅ 7, optimal conditions for initial CIP concentration, Fe

In this study, an electro-Fenton (EF) process with auto generation of Fenton`s catalyst (Fe2+) was proposed and its applicability in degradation and mineralization of Ciprofloxacin (CIP) antibiotic was examined. A graphite-felt sheet was used as cathode for continuous electro-generation of H2O2 and a trifle stainless steel plate (AISI 304) was used as sacrificial anode to provide ferrous catalyst. Effect of various operating parameters including current intensity (5–100 mA), reaction time (5–25 min), initial CIP concentration (10–150 mg/L) and initial pH (2–7) was investigated using Response Surface Methodology (RSM). Central Composite Design (CCD) under RSM was utilized to model the two main responses, namely, CIP and COD removals. Simultaneous optimization of responses under current intensity of 75 mA, treatment time of 20 min, initial CIP concentration of 45 mg/L and initial pH of 5 showed that 95.1% and 57.4% of CIP and COD removal efficiency could be achieved, respectively. High coefficients of determination (R2), for CIP and COD removal efficiency (0.92 and 0.94, respectively) indicated strong predictive capability of the models. BOD5/COD ratio, as an index of biodegradability, increased sharply from 0 to 0.42 under optimal condition. Two energy models, Electrical Energy Consumption (EEC) and EEC per unit COD removal, were introduced and the effect of operating parameters on them was evaluated. The intermediates of CIP degradation in aqueous solution were identified using ion chromatography and liquid chromatography coupled with mass spectrometry (LC–MS).

Polycyclic aromatic hydrocarbons (PAHs) distributed in air and soil are harmful because of their carcinogenicity, mutagenicity, and teratogenicity. Biodegradation is an environmentally friendly and economical approach to control these types of contaminants and has become an essential method for remediating environments contaminated with petroleum hydrocarbons. The bacteria are isolated and identified using a mineral nutrient medium containing PAHs as the sole source of carbon and energy and biochemical differential tests. Thus, this study focuses on some bacteria and fungi that degrade oil and hydrocarbons. This study provides a comprehensive, up-to-date, and efficient overview of petroleum hydrocarbon contaminant bioremediation considering hydrocarbon modification by microorganisms, emphasizing the new knowledge gained in recent years. The study shows that petroleum hydrocarbon contaminants are acceptably biodegradable by some microorganisms, and their removal by this method is cost-effective. Moreover, microbial biodegradation of petroleum hydrocarbon contaminants utilizes the enzymatic catalytic activities of microorganisms and increases the degradation of pollutants several times compared to conventional methods. Biological treatment is carried out in two ways: microbial stimulation and microbial propagation. In the first method, the growth of indigenous microorganisms in the area increases, and the pollution is eliminated. In the second method, on the other hand, there are no effective microorganisms in the area, so these microorganisms are added to the environment.

Despite the advances that have been achieved in developing wound dressings to date, wound healing still remains a challenge in the healthcare system. None of the wound dressings currently used clinically can mimic all the properties of normal and healthy skin. Electrospinning has gained remarkable attention in wound healing applications because of its excellent ability to form nanostructures similar to natural extracellular matrix (ECM). Electrospun dressing accelerates the wound healing process by transferring drugs or active agents to the wound site sooner. This review provides a concise overview of the recent developments in bioactive electrospun dressings, which are effective in treating acute and chronic wounds and can successfully heal the wound. We also discuss bioactive agents used to incorporate electrospun wound dressings to improve their therapeutic potential in wound healing. In addition, here we present commercial dressings loaded with bioactive agents with a comparison between their features and capabilities. Furthermore, we discuss challenges and promises and offer suggestions for future research on bioactive agent-loaded nanofiber membranes to guide future researchers in designing more effective dressing for wound healing and skin regeneration.

This study was aimed at the synthesis and characterization of ( δ -FeOOH)/MWCNTs nanocomposite as the catalyst for Ciprofloxacin (CIP) removal through a heterogeneous Fenton-like process. The proposed experimental design applies the central composite design (CCD) as a response surface methodology (RSM). The effect of influential parameters, including initial CIP concentration, catalyst dose, H 2 O2 concentration, initial pH, and reaction time on removal, were investigated. ( δ -FeOOH)/MWCNTs nanocomposite was synthesized using a single-step co-precipitation technique. Besides, nano-feroxyhyte and nanocomposite properties were characterized by transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), energy dispersive X-ray analysis (EDX), particle size analysis (PSA), X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and field emission scanning electron microscopy (FESEM). The inhibitory hale experiment was performed by Escherichia coli (E. coli) to evaluate the antibacterial activity. The optimal CIP removal efficiency (86.9%) was achieved by 131.6 min reaction time, CIP concentration of 10.0 mg/L, catalyst dosage of 23.5 mg, H2O2 concentration of 20.6 mM, and initial pH of 5.3, with a biodegradability index (BOD5/COD) of 0.35 Based on the results, ( δ -FeOOH)/MWCNTs showed a significant catalytic activity for CIP removal, which can be attributed to the simultaneous effects of advanced oxidation and absorption.

In this research, optimization of Homogeneous Fenton process was performed using Multi-Criteria Decision Analysis (MCDA) and Taguchi method to remove Ciprofloxacin (CIP) from an aqueous phase. Analytic Hierarchy Process (AHP) is one of the most comprehensive systems designed for multi-criteria decision making. In this study, paired comparisons based on the AHP method were performed for three criteria including (i) CIP removal, (ii) COD removal and (iii) Sludge to iron ratio (SIR) to select the best catalyst among FeSO4.7H2O and FeCl2.4H2O. Taguchi method was used to optimize parameters and their levels via Minitab16 Software. Influence of different parameters including initial CIP concentration, Fe (II) concentration, H2O2 concentration, pH, and reaction time on CIP removal from the aqueous phase were investigated. Using Expert Choice Software, and based on sensitivity analysis results, importance percentages for FeCl2.4H2O and FeSO4.7H2O were estimated as 63% and 37%, respectively. Taguchi optimal analysis indicated that a high S/N response ratio may be obtained with an initial CIP concentration of 10 mg/L, Fe2+ concentration of 50 mM, H2O2 concentration of 20 mM, pH of 3.5, and a reaction time of 20 min; making significance levels of the parameters as 81.63, 76.13, 75.13, 75 and 79.25, respectively. Analysis of variance (ANOVA) under Taguchi method showed that CIP concentration has the most impact on CIP removal with the highest sum of squares and lowest p-values (0.004). The maximum removal efficiency for two objectives, the antibiotic and COD, were 89.5% and 48%, respectively.

The main purpose of this experimental study was to optimize Homogeneous Fenton oxidation (HFO) and identification of oxidized by-products from degradation of Ciprofloxacin (CIP) using hybrid AHP-PROMETHEE, Response Surface Methodology (RSM) and High Performance Liquid Chromatography coupled with Mass Spectrometry (HPLC–MS). At the first step, an assessment was made for performances of two catalysts (FeSO4·7H2O and FeCl2·4H2O) based on hybrid AHP-PROMETHEE decision making method. Then, RSM was utilized to examine and optimize the influence of different variables including initial CIP concentration, Fe2+ concentration, [H2O2]/[ Fe2+] mole ratio and initial pH as independent variables on CIP removal, COD removal, and sludge to iron (SIR) as the response functions in a reaction time of 25 min. Weights of the mentioned responses as well as cost criteria were determined by AHP model based on pairwise comparison and then used as inputs to PROMETHEE method to develop hybrid AHP-PROMETHEE. Based on net flow results of this hybrid model, FeCl2·4H2O was more efficient because of its less environmental stability as well as lower SIR production. Then, optimization of experiments using Central Composite Design (CCD) under RSM was performed with the FeCl2·4H2O catalyst. Biodegradability of wastewater was determined in terms of BOD5/COD ratio, showing that HFO process is able to improve wastewater biodegradability from zero to 0.42. Finally, the main intermediaries of degradation and degradation pathways of CIP were investigated with (HPLC-MS). Major degradation pathways from hydroxylation of both piperazine and quinolonic rings, oxidation and cleavage of the piperazine ring, and defluorination (OH/F substitution) were suggested.

Optimization methods are used to study and survey the optimal values for input factors and effect of optimized parameters on response variables. In this study, the effect of different factors on ciprofloxacin (CIP) removal of water soluble was studied. In this regard, a multi-objective optimization was performed utilizing the Taguchi method based on a grey relational analysis. Optimum levels of factors were determined to optimize three responses simultaneously with grey Taguchi. Meanwhile, grey relational analysis was applied to model and optimize three target responses, namely, CIP removal, chemical oxygen demand (COD) removal, and sludge to iron ratio. Multi-objective optimization results obtained based on grey relational analysis showed that the optimal value of the input factors were CIP concentration of 100 mg/L, H2O2 concentration of 100 mM, Fe(II) concentration of 10 mM, pH of 3, and a reaction time of 15 min. To confirm the results, the values obtained through a confirmation test were examined. Multi-objective optimization results from process factors were determined by analysis of variance (ANOVA) analysis and grey Taguchi method. Based on ANOVA analysis for the grey relational grade, Fe(II) concentration and H2O2 concentration were found to be the most influencing factors.

In this article, the recent applications of different types of magnetic nanoparticles such as α-Fe2O3 (hematite), γ-Fe2O3 (maghemite), Fe3O4 (magnetite), hexagonal (MFe12O19), garnet (M3Fe5...

Lack of fresh water has been a major obstacle to development and flourishing in human history. Desalination provides a new vision toward fresh water production in the upcoming future. The study has proposed a simple mathematical equation and ANN models to simulate eight types of sea water RO membranes. The Artificial Neural Network (ANN) models have been developed to simulate TDS corresponding to the temperature (T, °C), flow rate (gpm) and recovery percentage. The feed data was generated by ROSA software. The model developed using a simple rational mathematical method. ANN models were trained using feed-forward back propagation algorithm with two hidden layers and various numbers of neurons in each layer. The model verification analysis proved both mathematical and ANN models to be highly accurate, reliable and practical for analyzing, designing, operating and optimizing of RO systems. The correlation coefficients (R) of 0.96 and 0.97, respectively, confirmed that the equation and ANN models resulted in this study are in good agreement with the measured data.

River water quality monitoring using traditional water sampling and laboratory analyses is expensive and time-consuming. The application of artificial neural network (ANN) models to simulate water quality parameters is cost-effective, quick, and reliable. This study provides two methods of mathematical and ANN modeling to simulate and forecast five important river water quality indicators (DO, TDS, SAR, BOD5, HCO3) correlated with variables such as EC, temperature, and pH which can be measured easily and almost with no cost. The mathematical method is based on polynomial fitting with least square method and the neural network model was developed using a feed-forward algorithm. The 35 years’ data were collected from 7 monitoring stations and 5 rivers located in southwest of Iran. DO concentration was simulated using an equation and a neural model. Two equations were calibrated for estimating TDS while SAR is simulated using a mathematical and neural model. Another two neural models were developed f...

Investigations indicated that the scorpions are scattered in all parts of Iran. Few researches have been carried out to identify and study morphology of the scorpions of Iran. In the present investigations, several species of scorpions from Kerman Province ( Iran ) have been identified. The scorpions usually live under the stones. To obtain the scorpions, heavy materials including stones, clod and so on, were moved by crow bar and woods. The specimens were captured with a tongs. To study the morphological characters and identify the scorpions, Olympus Lica 2000 stereo microscope and key identify to scorpions, were used. In the present research a species of scorpions belonged to Hottentotta genus and Buthidae family, is reported for the first time from Kerman Province (Iran). This species is called Hottentotta schach and has been collected from Manoujan area, situated in the south and southwest of Kerman Province. The H. schach is a rare species, it is shaggy and some parts of it'sbody are dark. This species lives in height over 1000 meter and also is found in mountainous areas. Beside of this species, 6 other species called: Compsobuthus matthiesseni,Androctonus crassicauda, Odontobuthus doriae, Mesobuthus eupeus, Sassanidotus gracilis, Orthochirus farzanpayi, from this family, are found in the mentioned area. In taxonomy, the scorpions are order belonging to arachnida class, phylum arthropoda, super phylum invertebrate sub kingdom of metazoan and kingdom of animal. The weather in south of Kerman Province is warm and relatively humid.

Food contamination by heavy metals can lead to the accumulation of these elements in the body of consumers and the contraction of diseases. Accordingly, heavy metal concentration in common carp fishes consumed in Shiraz, Iran was determined in the present study. The mean concentrations of Pb, Cd, Zn, and Cu were 0.23, 0.07, 0.47, and 0.59 mg/kg (dry weight), respectively. The average concentration of heavy metals in the muscle of common carps consumed in Shiraz was less than the permissible standard of the WHO and FAO. The estimated weekly intake (EWI) of the studied metals was below the provisional tolerable weekly intake (PTWI). The maximum and minimum relative risk (RR) equaled 48.93 and 0.55% of the total risk for Cd and Zn, respectively.

Today, due to the increase in the population, the growth of industry and the variety of chemical compounds, the quality of drinking water has decreased. Five important river water quality properties such as: dissolved oxygen (DO), total dissolved solids (TDS), total hardness (TH), alkalinity (ALK) and turbidity (TU) were estimated by parameters such as: electric conductivity (EC), temperature (T), and pH that could be measured easily with almost no costs. Simulate water quality parameters were examined with two methods of modeling include mathematical and Artificial Neural Networks (ANN). Mathematical methods are based on polynomial fitting with least square method and ANN modeling algorithms are feed-forward networks. All conditions/circumstances covered by neural network modeling were tested for all parameters in this study, except for Alkalinity. All optimum ANN models developed to simulate water quality parameters had precision value as R-value close to 0.99. The ANN model extended to simulate alkalinity with R-value equals to 0.82. Moreover, Surface fitting techniques were used to refine data sets. Presented models and equations are reliable/useable tools for studying water quality parameters at similar rivers, as a proper replacement for traditional water quality measuring equipment's.

In this study, a qualitative and quantitative change of groundwater resources of Damghan Basin was analyzed. Fifty-four active piezometric wells was used in the region which mostly suffer from shortage of drinkable water standard. Physical properties of 59 quality wells have been evaluated in order to determine the quality of groundwater by measuring factors such as pH, hardness, chloride content, electrical conductivity and total dissolved solid (TDS). By physical/chemical analyses, it was concluded that results for selected resources of Damghan Basin have been more comprehensive during 2008–2009 in comparison with other periods because scattered data cover all areas of the basin. By comparing the results with drinking water quality standards (WHO), assessment of water resources were conducted as acceptable to unsuitable. Hydrochemical perspective drawn using Piper diagram indicates that most of the selected water resources in the area contain chloride constituents. However, Na% values indicate that just 83 % of samples are permissible for using in irrigation purposes.

In the world’s water scarce regions, groundwater as an important and strategic resource needs proper assessment. An accurate forecasting needs to be performed in order to make a better identification of fluctuating nature of groundwater levels. In this study, groundwater level fluctuations of Kabudarahang aquifer was synchronized and verified. Investigation was conducted with usage and application of time series models. Groundwater level data during 2003–2014 are used for calibration and analyses were performed using Box-Jenkins models. Residual error analysis and comparison of observed and calculated groundwater levels were performed. Then a prediction model for groundwater level in Kabudarahang aquifer developed. The model was used for predicting the groundwater level during 2014–2017. Model results showed that the groundwater level in this aquifer will endure a 5 m decline for the next three upcoming years.

The Pharmaceutical contaminants specialist antibiotics into environment can create problems for both human health and environment. Ciprofloxacin (CIP), an antibiotic Fluoroquinolones group, has recently been used widely for infections treatment. The main purpose of the research was to develop a Full factorial method for degradation of CIP in aqueous solution by Fenton Homogenous process (Fe2+/H2O2). In order to compare the effects of the four parameters considered in the optimization of the oxidative process, a two level Full factorial experimental design (24) was utilized using JMP® software. These parameters were concentration of CIP ( ), concentration of Fe2+ ( ), concentration of H2O2 ( ) and time ( ) at ambient temperature and an acidic pH. In the optimal conditions of the initial concentration of CIP 80 mg/l, Fe2+ concentration of 5 mM, and H2O2 concentration of 51.2 mM degradation efficiency of CIP was 76% within 15 min. Under these conditions, the highest correlation coefficient proved between observed and predicted degradation efficiencies with R2= 0.996 and Adj-R2= 0.968. The reaction intermediates have been identified by LC-MS and BOD5/COD ratio for study biodegradability enhanced from zero to 0.32, showed that the Fenton Homogenous process was agreeable to biological treatment. Based on the results, this may be concluded that Fenton Homogenous process by Full factorial experimental design could be used to degrade CIP from aqueous solutions efficiently.