فهرست مطالب yousef dadban shahamat

Contamination of soils and aquatic environments with heavy metals is a serious and growing problem. Some pollutants, such as heavy metals like lead, are persistent, and most of these metals have high toxicity and are a significant environmental concern. Therefore, the present study aimed to remove lead from aqueous solutions by layered double hydroxide (LDH) nanocomposite deposited on magnetically activated carbon.

This experimental laboratory study was conducted on a small scale in a laboratory setting, and the samples were synthetically prepared. In this study, the effect of pH (4-10), adsorbent concentration (0.1-3 g/l), contact time (10-120 minutes), and initial concentrations of lead (5-20 mg/l) on the removal of lead ions was investigated. Process performance was evaluated based on the percentage of lead ion removal responses. Determination of the number of experiments, statistical analysis of the data, and optimization of lead ion removal were performed using the central composite design and surface-response method.

The effect of exploitation indicators on lead removal efficiency according to the analysis of variance (ANOVA) table showed that, apart from lead concentration, the rest of the indicators were significant, and respectively, the intensity of the effect and the highest value of F included LDH concentration, contact time, and pH. Lead removal efficiency was obtained 96.11% in optimal conditions with pH = 6.73, a reaction time of 67.71 minutes, a concentration of LDH nanocomposite adsorbent of 2.10 g/l, and an initial lead concentration of 10.98 mg/l. In these conditions, the model's utility was 100%. Based on the results, the highest correlation of adsorption kinetics was observed with the quadratic model. This model was selected as the most suitable to describe the kinetic behavior of LDH adsorbent deposited on magnetically activated carbon in the adsorption of lead ions from aqueous media.

The LDH adsorbent deposited on magnetically activated carbon is a suitable material for removing lead ions from aqueous solutions. Moreover, the utilization of a central composite design and surface response methodology to optimize the key variables in the lead ion removal process through adsorption is commendable.

One of the problems in the health systems of the world today is the prescription or overuse of drugs. Among these, antibiotics are of particular importance. Antibiotics are a group of drugs that are widely used in medicine and veterinary medicine. Cefixime (CFX) is also one of these antibiotics. The aim of this study was to investigate the removal efficiency of cefixime from synthetic sample using catalytic ozonation with Mg-Al layered double hydroxides Doped with zeolite.

In this experimental and laboratory study MgAl-LDH/Zeolite nanocomposite was used in laboratory reactor and ozonation to remove cefixime. Effect of pH variables (5,6,7,8,9), amount of nanocomposite (0.5,1,1.5,2,2.5 g/L), initial concentration of cefixime (5,10,15,20,25 mg/L) and reaction time (5,18.75,32.5,46.25,60 min) were examined to find the maximum mineralization efficiency and response surface methodology based on central composite design (CCD) was used to design experiments, analyze data and achieve optimal conditions. Analysis of variance was also used to analyze the date. This research was done in 2021-2022.

The maximum mineralization efficiency of cefixime under optimal conditions (pH=8.70, nanocomposite value=1.76 g/L, initial concentration of cefixime=24.06 mg/L, contact time=40.76 min) is 78%, which increases the target efficiency with increasing pH and contact time.

Catalytic ozonation process with Mg-Al layered double hydroxides nanocomposite Doped with zeolite can be used effectively and efficiency to remove cefixime in aqueous media.

 Currently, recycling of secondary effluent can be used sustainably as a new water source to minimize the water consumption in areas which are exposed to water crisis. Hence, it is necessary to appraise hybrid advanced treatment technologies performance and to determine the best alternative for reusing secondary effluent of industrial park in full-scale. 

 The secondary effluent (biological-treated) of the centralized industrial park wastewater treatment plant (Aq Qala, Golestan province, Iran) is introduced into combined systems such as (1) sand filter (SF) and membrane bioreactor (MBR), (2) SF, MBR and granular activated carbon (GAC) (3) SF and GAC (4) SF, MBR, GAC, and reverse osmosis (RO), as the hybrid advanced scenarios. 

 The effluent of SF/MBR/GAC/RO showed the highest quality (>99% removal efficiency). In this scenario, pH, silica, manganese, iron, total suspended solids, turbidity, total coliform, and chemical oxygen demand (COD), alkalinity, hardness, total dissolved solids (TDS), chloride, and sulfate were determined 6.93 ± 0.19, 1.4 ± 0.6 mg/L, not detectable (ND), ND, <2 ± 0.2 mg/L, <1 Nephelometric Turbidity unit (NTU), ND and <2 ± 0.2 mg/L, 54.8 ± 1 2.5 mg/L, 50 ± 17 mg/L, 100 ± 14.89 mg/L, 68 ± 10.9 mg/L, and 44 ± 3.67 mg/L were observed in the range of product water standard for sensitive industries. Also, the maximum of efficiency of SF/MBR, SF/MBR/GAC, and SF/GAC systems was obtained 97.75% (as total coliforms), 62.65% (as COD), and 55.8% (as COD), respectively. Other parameters removed slight about 2% to 40%. However, hardness, alkalinity, and manganese concentrations not reduced after these systems (0% efficiency). 

 The hybrid system of SF/MBR/GAC/RO was produced a clean and suitable water supply for the sensitive industries (e.g., intermediate-pressure boilers, cooling water, textile, etc.) of Aq Qala industrial park according to the environmental protection agency standards.

Today, chlorine and its compounds are the most popular elements employed for disinfecting water and wastewater due to their flexibility, cost-efficiency, and ease of use. This research aimed to optimally produce active chlorine by the electrochlorination method using titanium and platinum/titanium electrodes.

This experimental study was conducted in a batch flow of an electro-chlorination cell. The experimental design was performed using the Box Behnken method with a sample size of 34 experiments. The production of active chlorine was evaluated and compared on various operating factors, including current density (10-60 A/dm2), sodium chloride concentration (50-250 g/L), reaction time (5-120 min), and two types of anode electrodes of titanium and platinum/titanium and 316 cathode steel.

The results showed all four operating parameters had a significant effect on the active chlorine production and the highest effectiveness was related to electrolysis time, followed by current density, sodium chloride concentration, and anode electrode in descending order. The optimal operating conditions provided by the model for chlorine production included the electrolysis time of 120 min, current density of 60 A/dm2, concentration of sodium chloride of 187 g/L, and type of platinum/titanium anode electrode and 316 cathode steel electrode, which resulted in active chlorine of 65.95 g/L.

This method can be used as an effective method to produce chlorine to disinfect water and wastewater in treatment plants, and if replaced with gas chlorination systems, the safety problems of chlorine gas capsules will be solved.

With the expansion of urbanization and the development of industry, environmental pollution, including sources of drinking water to heavy metals, has become a global problem. Therefore, the present study was conducted to measure the concentration of lead and cadmium in the water of Gorgan distribution network.

This is a descriptive cross-sectional study in which the concentrations of heavy metals lead and cadmium were measured in 25 different stations of the Gorgan drinking water distribution network from April to September 2018 by atomic absorption device. Statistical analysis was used from SPSS ver 22 software. Also, zoning maps based on the concentration of these two metals were prepared by Geographic Information System (GIS) software.

The results of measuring the lead and cadmium concentration showed that all measured values are less than national and international standards. In general, the average concentrations of lead and cadmium were 4.38 and 0.1 μg/L, respectively. The results of Kruskal-Wallis test showed that there was a significant difference (p <0.01) between the concentrations obtained from lead metal in different months. Additionally, the distribution map of this lead and cadmium exhibited that in the central areas and some border areas, the concentration of these two metals is higher.

According to the obtained results, it can be seen that the concentration of heavy metals lead and cadmium in the water of Gorgan distribution network is within the permitted standards.

The presence of many synthetic dyes in aqueous solutions can cause carcinogenesis and mutagenicity and affect human health. Reactive Red 198 is one of the types of azo dyes with complex structure, toxic, carcinogenicity, mutagenicity properties, and tolerable in the environment, which is discharged to the environment through the sewage of textile industries. This study was performed to determine the mineralization of 198 reactive red dyes by the hybrid advanced oxidation process UV/US/H2O2/O3 from colored wastewater using central composite design.

In this descriptive-analytical study several factors affecting on dye mineralization process including the presence of ozone gas and ultraviolet rays (UV) as well as the initial dye concentration, Ultrasound (US), contact time, pH, and hydrogen peroxide were investigated. Experimental design and optimization were performed by design of experiment software using central composite design and its optimal conditions were determined.

The maximum dye degradation efficiency of 100% was performed under optimal conditions including initial dye concentration of 200 mg/L, reaction time of 34 minutes, hydrogen peroxide concentration of 27 mg/L and pH=9 in the presence of ozone gas flow, ultraviolet rays and ultrasonic waves. Also, the influence of factors on dye removal including ozone, UV, initial dye concentration, US, contact time, pH, and peroxide were  58.8%, 19.3%, 2.3%, 1.5%, 1.1%, 0.6 %and 0.2 % ,respectively.

UV/US/H2O2/O3 hybrid process with advantages such as performance and high speed can be recommended for wastewater treatment in various industries.

Paraquat (PQ) is the third most widely used herbicide in the world. This herbicide has the potential to damage cell membranes by lipid peroxidation and free radical attack. In this study, ZnO /rGO (ZG) heterogeneous photocatalyst was used for oxidation of PQ herbicide in aqueous solution under ultraviolet light irradiation.

In this experimental study, EDS, FE-SEM, BET, XRD, and FTIR analyzes were performed to determine the characteristics of synthesized catalyst. Effect of operating parameters, including solution pH, catalyst concentration, rGO percentage loading, PQ concentration, and UV-light intensity on degradation of PQ was studied in batch mode. Residual concentration of PQ and type and toxicity of intermediate compounds were measured by HPLC and GC-MS, respectively and toxicity test was done by Daphnia Magna. Studies on reusability of catalysts, effect of radical scavengers, and inorganic anions were also performed.

Under optimum conditions (pH=7, catalyst loading=10%, catalyst concentration=0.5 g/l, PQ concentration= 10mg/l, and UV-light intensity=220 mw/cm2), degradation and mineralization rate were 91.61% and 51% in 120 minutes, respectively. Radical scavenger experiments showed electron as the most effective factor in PQ oxidation process in ZG/UV system. In samples of agricultural run-off, degradation efficiency was 58.27%. Biotoxicity test also showed that toxic unit in pesticide-containing samples was 61.72 in raw samples that decreased to 12.19 in treated samples after 96 hours.

ZG/UV process has high efficiency and excellent catalytic activity, so, it the can be successfully used to degrade organic pollutants, especially pesticides, in wastewater.

The purpose of present study was to study absorbent ability of organic pollutants from warm water fish farms by synthesized nano-composite adsorbent. study was performed at different physicochemical condition of pH (5-8), effluent concentration (25-100 mg/L), contact time (15-90) minutes. Adsorption isotherm studies were analyzed using Freundlich, Langmuir models and adsorption kinetics studies using pseudo-first-order and pseudo-second-order kinetic models. The Langmuir and Freundlich isotherms, first and second order adsorption kinetics were investigated. The Langmuir and Freundlich isotherms for nitrite (R2 = 0.9076, R2 = 0.5911), phosphate (R2= 0.9307, R2= 0.5755) and ammonia (R2 = 0.7288 and R2 = 0.7549), respectively obtained. According to the results, the data of nitrite and phosphate pollutants were more consistent with the Langmuir model, but the data of ammonia pollutants were more consistent with the Freundlich model. According to the results, the adsorption of phosphate pollutants was more consistent with pseudo-first order kinetic model and the adsorption of nitrite and ammonia pollutants was more consistent with the pseudo-second order kinetic model.

Ammonia in form of ammonium ions is toxic and could decrease the dissolved oxygen in water and endanger the aquatic life. The aim of this study is the removal of ammonium using oxidation and adsorption by catalytic ozonation and clinoptilolite zeolite, respectively.

The research method is Experimental. First, optimal pH of ammonium adsorption on carbon catalyst (5 g/L), Garmsar and Firoozkooh zeolites and oxidation were determine. Then, in catalytic ozonation process, the effect of other variables on ammonium removal efficiency such as the concentration of carbonic catalyst (0.5- 50 g/L) and the reaction time were investigated. Then the effect of retention time and adsorbent concentration on adsorption of the remaining ammonium and nitrate produced by the oxidation process using zeolites and their modifications were determined.

Resuts:

 The results showed that optimum pH for the ammonium adsorption process by carbon catalyst, catalytic ozonation and zeolite was 8, 9 and 8, respectively. However, the optimum pH 4 was determined for nitrate removal. The highest ammonium absorption capacity was related to natural Firoozookh zeolite and 18.5 mg/g, and the effect of ligand and acid modification decreased 12 and 14% of absorbed capacity, respectively. It is also, the highest nitrate removal efficiency was related to Garmsar ligand modified zeolite (98%) and an absorption capacity of 11.2 mg/g. In the COP/absorption process the concentration of ammonium was decreased to 0.6 m /L.

This method effectively eliminates ammonium, and the modification of zeolite with cationic surfactant increases the efficiency of nitrate removal and the concentrates of all pollutants are brought below standards.

Essential oils are volatile components which produced by different parts of the medicinal plants. These components have antibacterial potential and have been used throughout the world as a common, time-tested spice. The present study aimed to assess theantibacterial effects of cinnamon essential oil on several foodborne bacteria, including Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa.

Literature search was performed in databases such as PubMed, Google Scholar, SID, Scopus, ScienceDirect, and Elsevier to find the relevant articles published during 1987-2018 using keywords such as medicinal plants, cinnamon essential oil, foodborne diseases, and foodborne pathogens.

Cinnamon essential oil has been reported to have several antibacterial components, which could inhibit the growth of some foodborne pathogens. Therefore, it could be used in foods, cosmetics, and hygienic industries alone or in combination with other antimicrobial agents to reduce the risk of contamination and increase the shelf life of foods.

Proper doses of cinnamon essential oil can be applied as a food preservative in the food industry as long as the taste of the food is not affected.

Air pollution has been recognized as the most important environmental risk factor worldwide. Benzene which is one of the four pollutants attributed to BTEX (Benzene, Toluene, Ethylbenzene, and Xylene) has been proven to be a carcinogenic component. These pollutants can be easily absorbed and taken into the body via inhalation. With this background in mind, the present study aimed to investigate the concentration of benzene and its zoning in Tehran air using Geographic Information System (GIS)  within 2016-2017.

In the present study, 26 sampling stations were selected in different parts of the city and sampled in four seasons to determine benzene concentration, as well as other meteorological parameters, such as temperature, humidity, and wind velocity. Thereafter, the obtained data were analyzed in SPSS software (version 22) using the one-way analysis of variance and correlation. Subsequently, modeling of pollutant distribution was performed using ArcGIS software. 

The obtained results demonstrated that in terms of location, the maximum and minimum annual mean concentrations of benzene were calculated at 45.12±15 and 12.36±8 μg/m3, respectively, in the center and north of the city. Temporally, the maximum and minimum values were measured at 47±17 µg/m3 in autumn and 9.82±7 µg/m3 in spring, respectively. Statistical analysis revealed that emission of this pollutant showed a significant relationship with geographical direction and wind velocity (P<0.01).

The average annual concentration of benzene in different geographical areas of Tehran was higher than the standard values of clean air. Therefore, it is suggested that fundamental measures be implemented to control this chemical compound.

The discharge of untreated wastewater containing toxic and resistant compounds into the environment is a serious threat for ecosystems. Therefore, this study was conducted to evaluate the treatment of poison production factory wastewater using heterogeneous catalytic ozonation process
(COP).

Magnetic carbon nanocomposite was used as a catalyst at concentrations of 1, 2, and 4 g/L. Its effect on improving the treatment process was evaluated at reaction time of 30, 60, 90, and 120 minutes. At the end of each experiment, parameters including total organic carbon (TOC), chemical oxygen demand (COD), biological oxygen demand (BOD5), pH, electrical conductivity (EC), and turbidity were measured.

It was revealed that in single ozonation process (SOP), the maximum removal efficiencies of TOC, COD, and BOD5 were achieved at reaction time of 120 minutes as 56%, 40%, and 11.7%, respectively. By adding the catalyst to the wastewater, the treatment process was improved, so that the
maximum removal efficiencies of COD (91%), TOC (73%), and BOD5 (74%) were obtained at catalyst concentration of 4 g/L. Under this condition, BOD5/COD ratio increased from 0.22 to 0.64. Also, the results of analysis of ozone consumption per each mg of reduced COD showed that its amount sharply decreased from 2.1 mgO3/mg COD removal in the SOP, to 0.34 mgO3/mg COD removal in the COP. The results of kinetic reaction analysis also revealed that the rate constant increased from 0.007 to 0.02 min-1.

According to the results, it can be concluded that the COP at a catalyst concentration of 4 g/L, by decomposing resistant compounds and increasing the biodegradability, can be used as a suitable pre-treatment method for biological processes.

 In this study, the concentration of particulate matter (PM)2.5and PM10particles and volatile organic compounds (VOCs) was measured from July of 2016 to June of 2017 in Gorgan City and the values of the air quality index (AQI) for particles were calculated and investigated. 

 The concentrations of PM2.5, PM10, and VOCs were measured at eight stations in the city, and the relationship between different atmospheric conditions and the concentration of pollutants was assessed by statistical tests of variance analysis. Furthermore, the AQI values for the particles were measured, and based on the values of this index, using ArcGIS 10.3 software (ESRI Compony, USA), the zoning maps were prepared. 

 The average concentrations of PM2.5, PM10, and VOCs in the eight stations were 30.6 μg/m3, 41.3 μg/m3, and 0.82 ppm, respectively. The average concentration of PM2.5and VOCs is higher than Environmental Protection Agency and clean air standards. Analysis of variance test was showed that the concentration difference of particles in different stations was not significant (P > 0.05), but for VOCs concentration, there was a statistically significant difference between the station of Seyed Masoud restaurant and Terminal square (P < 0.05). Furthermore, the results were showed that the temperature has an inverse relationship with the concentration of pollutants. AQI values for PM2.5in the cold months of the year and in the central parts of the city were in the range of 101–150. The maximum AQI for PM10was equivalent to 55, which was in December 2016. 

 The air quality of Gorgan City was not in desirable conditions due to the high concentration of pollutants, especially PM2.5and VOCs, and should be taken control proceedings.

Previous epidemiological studies suggested a close correlation between suspended particles and the prevalence of respiratory diseases, cardiovascular problems, cancer, and mortality. Moreover, it was reported that the city space contains pollutions of motionless and moving sources. Therefore, the aim of this study was to determine the concentration and release status of PM10 and PM2.5 particles in the air of Gorgan, Iran in 2016-2017 and to provide effective solutions. In this descriptive cross-sectional study, the concentration of air pollutants in Gorgan was measured at eight stations in different parts of the city for one year during July 2016-June 2017. Afterwards, the results of monthly PM2.5 and PM10 measurements by the portable device were modeled following the calculation of the quality index and estimation of their effect on health in the Geographic Information System using the Air Quality Index (AQI) Calculator software. In addition, the measurements were compared with national and international standard values. Furthermore, solutions were provided for reducing pollution. Our findings demonstrated that the highest amount of PM2.5 and PM10 were recorded in December (116 and 76 μg/m3) and the lowest was in April (40 and 34 μg/m3). The results of one-way analysis of variance revealed a significant difference in the mean concentrations of the two particles between months. According to the results of this study, air inversion in cold seasons was effective in the concentration of these pollutants. The annual mean of PM10 and PM2.5 was reported as 41 and 30 μg/m3, respectively. The latter means were lower and higher than the EPA standards of 50 and 12 μg/m3, respectively. The results of the current investigation showed that the highest AQI was related to PM2.5 in the central regions of the city, Municipality Square, and Mazandaran Square. In addition, the highest PM10 pollution was measured in the central and southern parts of the city. This could be attributed to the high density of cars, which is the most important factor in the production of particles in cities.

One of the important problems in the management of waste is the health and environmental hazards of the leachate leakage of urban waste landfills to groundwater. This research aimed to investigate the improvement of the landfill properties using recycled polymer. In this study, PET: Polyethylene Terephthalate and clay were mixed with the ratio of 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 and 1 wt%. Moreover, Moreover, its effect on the quality parameters of clay, including consolidation, settlement, shear stress, adhesion, and infiltration were determined in soil mechanics laboratory located in the city of Gorgan. All experiments were conducted based on American Society for Testing and Materials. Results showed that the internal friction angle in clay and clay composed with polymer were 20.93 wt% and 30.3 wt%, respectively. Moreover, the compaction of clay decreased from 0.163 g/cm2 to 0.110 g/cm2. Permeability results showed that the use of PET decreased the permeability of soil from 1.82 E-3cm/min to 1.57 E-3cm/min. The use of recycled polymer can improve the soil conditions of landfills in terms of permeability and resistance to leaching, which could reduce the volume and the recycling process of waste. Moreover, this issue contribute to the quality and strength of the substrate to prevent environmental contamination as well as groundwater polution.

Ceftriaxone is widely used for healing the infectious diseases. Not being treated in hospital wastewater treatment systems, this antibiotic has the possibility of entering into the aqueous environmental and the danger of microbial resistance in these environments also increases. This study aims to examine the efficiency of catalytic ozonation process by using magnesium oxide nanoparticles to remove ceftriaxone from aqueous solutions. In this study, the effect of pH, ozone dose, reaction time, catalyst dose and initial antibiotic concentration for ceftriaxone removal were studied using a cylindrical-shaped experimental reactor through semi-batch method. The residual concentration of ceftriaxone was determined by spectrophotometer. The experiment was carried out based on the one factor at a time method and finally the optimum efficiency of ceftriaxone removal and its desired conditions were determined. The best condition of the reactor obtained in pH 11, the catalyst dose of 1g/l, ozone dose of 18.384mg/min, pollution concentration of 10mg/l and reaction time of 30 min which showed 86% of ceftriaxone removal. Due to an increase in ozone retention time, the use of magnesium oxide nanoparticles in ozonation process also increased the antibiotic removal. It leads to a decrease in treatment costs because of a decrease in ozone consumption in an industrial scale.

Background and Presence of natural organic substances in surface water supplies could be harmful and have adverse effects on drinking water treatment due to many practical and hygiene reasons. This study aimed at investigating the efficiency of catalytic ozonation process in removal and mineralization of humic substances in water resources in north of Iran.
Water treatment plants in Gorgan and Sari were studied (2017). First, the concentration of humic substances was measured in water. Then catalytic ozonation process (COP) of the water samples were performed using semi-continuous cylindrical reactor. The effects of some parameters such as reaction time (0-60 min) and catalyst dosage (0 and 3 g/L) on removal efficiency and mineralization of humic substances were investigated. After determining the kinetics constants of reactions, the removal efficiencies were compared between COP and single ozonation process (SOP).
The concentrations of humic substances in water samples in Sari and Gorgan were 15.22 ± 5.39 and 18.62 ± 6.16 mg/L, respectively. The efficiency of removal of humic acid and its mineralization in the COP process under optimal conditions for Naharkhoran, Sari Salim Bahram, and Alangdare water treatment plants, were 100, 84.21, 88.18%, and 100, 83.4, and 78.03%, respectively. The reaction kinetics were first-order and their rates were 2.6, 2.9, and 3.7 folds more than those of the COP process, respectively
Using magnetic activated carbon catalyst coupled with ozonation process, compared to SOP, is 40% more efficient in removal of humic substances. Also, by reducing the ozonation time and the easy recovery of the catalyst and improving the process efficiency it reduces the costs.

Background and Environmental pollution by heavy metals and their transfer to soil and crops are a growing global problem. This study aimed to measure the concentrations of heavy metals in wastewater and sludge wastewater treatment plant in Gorgan, Iran.
In this cross-sectional study, 176 samples of effluent, and returned and dried sludges were analyzed in wastewater treatment plant in Gorgan, during six months in 2016. The concentration of Pb, Cd, Ni, and Cr were determined using polarography (Metrohm797 AV) and furnace atomic adsorption spectroscopy (AA 240 Varian Co.) in the laboratory of Health Faculty in Golestan University of Medical Sciences.
The average concentrations of Pb, Cd, Ni, and Cr in the effluent were 0.105 ± 0.06, 0.0089 ± 0.008, 0.095 ± 0.108, and 0.102 ± 0.175 mg /L, respectively. The concentrations of Pb, Cd, Ni, and Cr in returned sludge were 323.48 ± 217.65, 2.44 ± 3.3, 354.14 ± 322.79, and 388.53 ± 252.59 mg /kg of dry weight, respectively. Also, in dried sludge, the average concentrations of lead, cadmium, nickel, and chromium were 58.48±2.67, N.D, 30.31±1.98, and 506.25±813.81 mg/kg of dry weight, respectively.
The concentrations of heavy metals in wastewater effluent and dried sludge, except in returned sludge, were below the standards. Due to long-term use of effluents, necessity of treatment of other parameters, and the effect of bioaccumulation of metals in sludge, caution should be taken for their agricultural application. Also, because of importance of this type of contaminants in soil and food products, continuous monitoring by water companies is highly necessary.

Water resources in karst areas are very important water supply from the aspects of quantity and quality in the world. Due to the wide scattering these resources in the country and in the province, this study was performed to determine the quality of karst water resources in Golestan province.
In this study the chemical and microbial quality of water of the most important Karst resources of Golestan Province (Iran) due to potability and irrigational consumption was performed in the Gorgan, Kalaleh, Azadshahr and Galikash cities, as a sectional manner within the two seasons of 2014-2015. For this purpose, 10 parameters of 12 water Karst resources were determined and qualitative classification of water was performed using Aq.qa software.
Results showed that the qualities of the total water resources are in the ranges of hard and very hard waters. The survey of water quality class showed that most of water samples were excellent in two seasons. Due to the Wilcox quality index, some of the resources as appropriate for agricultural use and some are not. All of samples are in middle class for drinking and no bacterial contaminants observed in water samples.
Generally, considering the importance of Karst resources in terms of proper quality and quantity compared with water dams in the country and the Golestan Province, comprehensive survey and study in quantitative and qualitative aspects of these resources should be done as a solution for supplying of agricultural irrigations and drinking waters.

Background and Phytic acid plays a major role in reducing the bioavailability of minerals in food. The aim of this study was to evaluate the effect of controlled sourdough fermentation on reduction of phytate content in dough and bread produced by whole wheat flour containing Lactobacillus plantarum and Lactobacillus brevis.
This experimental study was carried out as a joint project in Golestan University of Medical Sciences and Gorgan University of Agricultural Sciences and Natural Resources. After isolation of two dominant lactobacillus isolates from whole wheat sourdough and their molecular identification, the effect of controlled sourdough fermentation (dominant isolates were used as starter culture, under treatments (as separate or mixed with equal proportions) of 28, 32, 36 °C fermentation temperatures and 16, 24, 32 h fermentation times) was examined on phytate content of produced dough and bread, using a spectrophotometric assay based on the measurement of iron.
Sequencing of PCR products led to identification of Lactobacillus plantarum and Lactobacillus brevis as the dominant lactobacillus isolates from whole wheat sourdough. According to statistical analysis, by increasing fermentation time and temperature, the amount of phytate significantly decreased in dough and bread produced by each of dominant isolates (P≤ 0.05). Furthermore, mixture of lactobacillus as starter culture was more effective on phytate reduction compared with using them separately.
Our results showed that controlled fermentation of whole wheat sourdough have significant effect on reduction of phytate and increasing the bioavailability of bread minerals.

Background and Many conventional disinfection methods of effluents raise some health, efficiency and economic concerns. In order to increase the efficiency of disinfection of real effluent, in this study, the catalytic ozonation process was performed and economically compared with chlorination.
Magnetic activated carbon was used as acatalyst in a semi-continuous reactor for disinfection of effluent of municipal wastewater treatment plant in Bandargaz, Iran in 2015. The efficiency of disinfection was determined by thermo-tolerant coliform as indication, and the effect of parameters such as catalyst concentration (0, 0.5, 1, 2, and 5 g/L), initial number of coliforms, contact time (1, 2, 5, 10, 20 and 40 min) and catalyst reuse on disinfection process was evaluated. Finally economic comparison was done with the chlorination.
The results showed that the efficiency of disinfection was increased by increase in the concentration of carbon nano-composite and contact time; at 1 g/L concentration of Catalyst about 1.99 log reduction was observed after 2 min exposure time in which the effluent standards were obtained; while 1.91 log reduction of micro-organisms was measured for single ozonation. The first-order kinetics constant of single ozonation (0.42 min-1) showed an approximately 9-fold increase when the catalyst (2 g/L) was added to the solution. After 7 times reuse of nano-composite, the diminution of efficiency was negligible (1.5%); and more than 57% fall of the cost was observed in a 5-year operational period compared with chlorination.
The catalytic ozonation with the new catalyst of effluent could effectively disinfect the effluent in a short-contact-time, and due to economic considerations it can be used as an effective and economical method in wastewater treatment plants.

Background and Molasses is colored, toxic and non-biodegradable compound which is found in the wastewater of fermentation industries. This study investigated the kinetic and efficiency of molass dye removal and mineralization in the yeast wastewater using nanocomposite catalysts in ozonation process.
The catalytic ozonation process (COP) of colored effluent of biological treatment of yeast production factory was carried out using semi-continuous flow cylindrical reactor and the effects of operational parameters such as initial pH value (4-10) and reaction time (5-60 min) on removal efficiency of dye and mineralization were investigated. After determining the kinetic parameters of reaction, the effects of some other parameters such as adsorption and reuse of the catalyst were calculated and the efficiency was compared with single ozonation process (SOP) and granular carbon as catalyst.
The removal efficiency of dye of molass factories effluent and its kinetic, at the condition of initial dye concentration 4521 ADMI, catalyst concentration 2 g/L and 60 min reaction time were 95% and 0.045 min-1, respectively; while these parameters in SOP and granular activated carbon as catalyst were 71% with 0.018 min-1 and 86% with 0.028 min-1, respectively. But, the mineralization and its kinetic in COP were 74% and 0.023 min-1, respectively, in which initial TOC was decreased from 510 mg/L to 132 mg/L.
The nanocomposite was found to have the best efficiency in dye degradation and TOC removal and it is easy to recover and reuse over and over by magnet. The main mechanism of dye degradation in COP was chemical oxidation and less occurred by adsorption.

Selling of bottled water has been increasing around the world, because many people believe that this type of water is an ideal option for drinking particularly for the immunosuppressed people. Thus, we aimed to investigate fungal contamination in bottled water in Gorgan, Iran
Four-hundred bottled water samples belonging to 10 famous brands were collected from different retail outlets in Gorgan, from May 2014 to April 2015. Fungi identification was performed by Subdextroz agar and Potitodextroz agar. Data analysis was performed by chi-square test (P Findings: Rodotrolla fungal spp was identified in 164 (41%) of all tested samples. About 32% of contamination was related to 60 days after bottling, and its rate was the same in small and big bottles. All brands were tainted but the difference was not significant.
Based on the results, some water bottles have fungal contamination that is in contravention of bottled water regulation. Hence, it is a necessity to implement water safety plan to improve the quality of bottled water.

Background and 2, 4 dinitrophenol is the most important nitrophenol compound that is widely used in paints, adhesives, wood preservatives, solvents, pesticides, and explosive materials. Because of the high toxicity and non-biodegradability of 2, 4 DNP, must be prevented from entering the water body. The aim of this study was to evaluate the performance of ordered mesoporous carbon CMK-3 in adsorption of 2, 4 dinitrophenol from aqueous solutions and the effect of various parameters on the performance of this process.
In this experimental study, mesoporous carbon, CMK-3 was prepared using hexagonal SBA-15 mesoporous silica in a batch reactor. The synthesized materials were characterized by XRD, BET and TEM. After Synthesis of CMK-3, the effect of different parameters were investigated on adsorption process including pH (3-11), contact time (20 -180 min) initial concentration of 2, 4 dinitrophenol (10-500mg/L), and adsorbent dose (0.2-1.2 gr/L).
Removal efficiency increased when pH and initial concentration of 2, 4-dinitrophenol decreased and contact time and adsorbant doze increased. The optimum pH was 5 and the equilibrium time was 100 minutes. The optimal dose of CMK-3 was 0.4 g/L and the adsorption capacity of 2, 4 dinitrophenol by CMK-3 was 194 mg/g.
In general, mesoporous carbon CMK-3 showed high capacity in removal of 2,4 dinitrophenol from aqueous solutions. Therefore, it can be used in the treatment of wastewater containing 2,4 dinitrophenol.

Background and Quality of surface waters is important for different uses and identification of contaminated sites and pollutants leads to appropriate use of water. So, the aim of this study was to evaluate the quality of water Babolrood.
In this cross-sectional study, sampling was conducted in ten stations during summer 2013. Data was analyzed using National Sanitation Foundation Water Quality Index (NSFWQI) and SPSS, and then the river’s path was zoned by Geographic Information System (GIS).
Based on NSFWQI, the best status was found in second station (79, good) and the worst was observed in station 10 (52, moderate).
Based on NSFWQI, the quality of river was good in upstream and moderate in downstream, indicating human as the main responsible for low quality of water.