Showing 74 results for Rat
A Koolivand, K Naddafi, R Nabizadeh, A Jonidi Jafari, M Yunesian, K Yaghmaiean, S Naseri,
Volume 9, Issue 3 (12-2016)
Abstract
Background and Objective: The performance of in-vessel composting process, as one of the most effective methods of oily sludge treatment, depends on factors such as nutrients and temperature. Therefore, it is crucial to investigate the trend of changes of these factors. The aim of the present study was to investigate the trend of changes of organic carbon, nitrogen, phosphorus, and temperature during the composting of bottom sludge of crude oil storage tanks.
Materials and Methods: The sludge was mixed with the immature compost at the various ratios of sludge to compost including 1:2, 1:4, 1:6, 1:8, and 1:10 with the initial C/N/P of 100/5/1 and then was composted for a period of 10 weeks. The process of mixing and moisture adjustment of the mixtures was done 3 times a day during the composting period. Sampling and analysis were performed every week for organic carbon, nitrogen, and phosphorus and every day for temperature.
Results: The research indicated that the concentrations of organic carbon, nitrogen, and phosphorus were decreased sharply during the first weeks of the process and then they were decreased gently. At the final stage of the composting, the ratios of C/N and C/P increased from 20:1 and 100:1 to 26:1 and 166:1, respectively. In addition, the temperature of the reactors was kept in the mesophilic range during the process period.
Conclusion: The similar trend of decrease of organic carbon, nitrogen, and phosphorus in the composting reactors is an indication of decreasing the activity of the microorganisms involved in petroleum hydrocarbons degradation.
M Heydari, R Nabizadeh Nodehi, M Ali Mohammadi, K Yaghmaeian,
Volume 10, Issue 1 (6-2017)
Abstract
Background and Objective: Bottled water consumption is rapidly increasing in recent years for various reasons.The main aim of this study was to survey the geological origin of Iranian bottled water and determine compliance or lack of compliance with the experimental data obtained through sampling 71 brands of drinking bottled water and mineral water.
Materials and Methods: In this study the coordinates of access points as a georef of the chosen points were launched on the "Iran geological map" and "Iran mineral and warm water map." The compliance of laboratory data and water types with the geological data were evaluated and compared with the important ionic ratios of the extracted water through using awh software.
Results: In examining 71 brands of the bottled water, 28% of the brands did not agree with the laboratory results, reflected by observing higher levels of bicarbonate in 50% of the bottled waters than those of the geological data.. Additionally, 70% of water types were calcic bicarbonate. In the bottled waters from North Alborz range with coastal Time deposits around the Caspian Sea, there was a source of brine or sea water that was about 55% of this amount.
Conclusion: Water pass through different geological structures and the dissolution phenomenon might be an important factor for the observed disagreement. Because chemical treatment and use of additives on mineral waters are not allowed it prompts further studies to determine the cause and origin of this issue through sampling from the factory and water source.
N Pourang, F Esmaeili, M Ranjbarian,
Volume 10, Issue 1 (6-2017)
Abstract
Background and Objective: Identification of potential risks in laboratories and trying to create safe conditions for the staff is very important from different aspects. The main objective of this study was to evaluate the potential risks in the laboratories of three research centers affiliated to Iranian Fisheries Science Research Institute.
Materials and Methods: In order to assess and classify risks associated with working in the laboratories (11 laboratories of the Persian Gulf and Oman Sea Ecological Research Center, 9 laboratories of National Shrimp Research Center and 2 laboratories of National Aquatic Organisms Processing Center), the method of "Failure Mode Effects Analysis" (FMEA) as well as statistical methods (concerning compare means) were used.
Results: The risk levels in all the laboratories of the Persian Gulf and Oman Sea Ecological Research Center, except for benthos laboratory, could be evaluated as moderate or high. Only in the case of the sample preparation laboratory, significant differences between the values of RPN before and after corrective action was observed. However, in this case the corrective actions have not been effective in decreasing the risk level. In most laboratories of National Shrimp Research Center, the corrective actions were effective in reducing the risk levels (with the exception of three laboratories). In both laboratories of National Aquatic Organisms Processing Center, after the corrective actions, the risk levels were sharply reduced.
Conclusion: Considering the high level of risk in many evaluated laboratories, appropriate corrective actions were proposed. But after the second-stage evaluation, it was realized that the proposed corrective measures in some laboratories (especially in the Persian Gulf and Oman Sea Ecological Research Center) were notperformed sufficiently and hence the risk still was remained at critical or semi-critical level
S Mazloomi, A Esmaeili - Sari, N Bahramifar, M Moeinaddini,
Volume 10, Issue 2 (9-2017)
Abstract
Background and Objective: Street dust is considered as one of the important sources of particulate matters and heavy metals in the atmosphere. The goal of this study was to assess the heavy metals pollution in street dust of Tehran and evaluate their ecological risk.
Materials and Methods: The sampling of street dust was carried out in two areas at the east and west of Tehran. After preparation of samples, the concentration of heavy metals was measured by ICP-MS. The pollution level of heavy metals in the street dust was assessed using geo-accumulation index (Igeo), pollution index (PI), integrated pollution index (IPI), enrichment factor (EF) and ecological risk index (RI).
Results: The results of the calculations of the indices showed that the street dust in both studied areas was non-polluted with Li, Al, Ti, V, Cr, Mn, Fe, Ni, Sr and Ba. The origin of these elements was mainly natural sources. However, Cd, Cu, As, Zn, Sn and Pb had medium to high level of contamination. These elements had a very high to extremely high enrichment in both areas. Their origin was mainly anthropogenic sources. The ecological risk index indicated a moderate ecological risk for the east and a low ecological risk for the west area.
Conclusion: The higher level of lead in the East is the main reason of higher ecological risk of this area. Therefore, the heavy metals pollution of the street dust, especially lead and its enterance into the environment, should be considered in this area.
R Bagheri, S Sobhanardakani, B Lorestani,
Volume 10, Issue 3 (12-2017)
Abstract
Background and Objective: In countries such as Iran that are facing with water scarcity and water crisis, paying attention to the quantity, quality and sustainable use of water resources is very significant. Petrochemical processes discharge pollutants into the environment, contaminating surface water resources. Therefore, treatment of the wastewater of these industries is necessary. Due to the capabilities of AHP process such as generalization, consideration of various parameters, multi-dimensional selection and quantifying the qualitative parameters by experts, the current study was carried out to select the best wastewater treatment alternative for HDPE plant of petrochemical research and technology company-Arak center based on AHP in 2016.
Materials and Methods: In this study, both sequencing batch reactors (SBR) and extended aeration activated sludge (EAAS) systems based on environmental, technical-functional, economic and management criteria's according to the expert's opinion were weighted. Then, the paired comparisons of the selected wastewater treatment systems for each criterion were developed. Finally, the results were analyzed to select the best wastewater treatment systems for HDPE unit of petrochemical industries using Expert Choice 11 Software.
Results: The results showed that the SBR wastewater treatment system was the best method for the wastewater treatment of HDPE plant of petrochemical research and technology company-Arak center as compared with the ESSA system. Also, consistency ratio was ranged from 0 to 0.10 in all emphases. Based on the results of the sensitivity analysis, the SBR system had the highest priority of economic and environmental criteria. The ESSA system had the highest priority of technical-functional and management criteria.
Conclusion: Based on the results, although ESSA method requires more maintainance and management than the SBR method, due to increasing requirement for the compliance of the output effluent quality with permissible limits and the need for less land for the establishment of the treatment plant, the SBR method was selected to be the most suitable process for HDPE plant wastewater treatment.
A Nazarpour, N Ghanavati, T Babaenejad,
Volume 10, Issue 3 (12-2017)
Abstract
Background and Objective: The aim of the present study was to investigate the concentration, enrichment factor, Nemrow integrated pollution index, and potential ecological risk of heavy metals including (Pb, Ni, Cu, Zn, Cd, V and Cr) in surface soils of Ahvaz oil filed.
Materials and Methods: For this purpose, 49 soil samples with a systematic scheme from Ahvaz oil field were analyzed by atomic absorption method.
Results: The mean concentration of heavy metals was as follow: Pb (251.20), Ni (94.6), Cu (75.80), Zn (132.84), Cd (0.69), V (4.97) and Cr (141.48) (mg/kg). The average value of enrichment factor in the soil samples decreased as Pb>Ni>Cu>Cr>Zn>Cd>V. Nemrow integrated pollution index (NIPI) indicated high level of pollution for the studied heavy metals except V. The Potential ecological risk of the studied heavy metals showed a low potential ecological risk for V, Cd, Zn and Cr; Cu showed a moderate risk and Ni and Pb indicated a considerable ecological risk. The mean value of the risk index indicated that 27 (55.10%) of the soil samples with a moderate risk, 21 (42.85%) with a considerable risk and one sample (2.05%) with a high ecological risk.
Conclusion: The obtained results from the enrichment factor, Potential ecological risk, and risk index indicated that the main source of heavy metals in the study area were anthropogenic sources such as oil drilling activities.
K Ezimand, Aa Kakroodi,
Volume 10, Issue 4 (3-2018)
Abstract
Background and Objective: Ground level ozone (O3) is one of most dangerous pollutants for human health in urban areas. The aim of this study was to identify the factors affecting the formation of ozone and modeling the spatial and temporal variations of ozone concentration in Tehran metropolitan area.
Materials and Methods: The data used in this research included meteorological data and pollution concentration data for 2014. First, we studied the impact and correlation of parameters to ozone concentration using the coefficient of Pearson, and then we did modeling of ozone concentration using a multivariate linear regression method.
Results: The developed model had the ability to describe 79% of the data changes for 2014. The temporal analysis of the ozone concentration showed that the best coefficient of determination of the model was R2 = 0.771 in the summer and R2 = 0.778 in July. These results also showed that among the air quality monitoring station of Tehran, station 4 had the lowest coefficient of determination (R2 = 0.6) and Aqdasieh station had the highest coefficient of determination (R2 = 0.79). Finally, the spatial distribution of the estimated ozone concentration was consistent with the measured ozone concentration at the station level.
Conclusion: According to the results, all the parameters related to air pollution concentration and meteorological parameters were effective parameters on modeling of ozone concentration on the ground level. The spatial distribution of ozone concentration in Tehran showed a greater concentration of ozone in the South and East than the North and West of the city.
R Farahmandfar, S Rashidaei Abandansari , E Maghsoudlou, M Asnaashari,
Volume 11, Issue 1 (6-2018)
Abstract
Background and Objective: Wheat is one of the most important cereals due to the supply of much of the flour used in bread making in most countries, such as Iran. Wheat contamination with mycotoxins is subject to different production and maintenance conditions. As a carcinogen and mutagen, monitoring the amount of mycotoxins in imported wheat and prevention of the entry of low quality wheat to the food chain are essential. Therefore, this study was conducted to determine the contamination of the wheat imported to Mazandaran province.
Materials and Methods: Samples of the wheat imported from Caspian Sea countries were evaluated for moisture content and mycotoxins contamination (ochratoxin A, zearalenone and deoxynivalenol). Mycotoxins contamination was determined by HPLC method via purifying with immunoaffinity column for ochratoxin A and zearalenone, and DONSPE column for deoxynivalenol.
Results: The results of this study showed that the average of ochratoxin A, zearalenone, and deoxynivalenol in the samples were 2.24, 133.50 and 181.66 ng/g, respectively.
Conclusion: All the samples were within the acceptable level for mycotoxin according to the permissible limits of Iran National Standard. Additionally, a direct relation between deoxynivalenol and moisture content of the samples (-0.092) was not observed and the correlation between moisture content and ochratoxin A and zearalenone was 0.104 and 0.168, respectively.
N Farrar, Sr Golestaneh, S Rasoulian,
Volume 11, Issue 3 (12-2018)
Abstract
Background and Objective: The sewer system is one of the important and suitable areas for the growth and reproduction of American Cockroach Periplaneta americana (L.) in Bushehr. This project was implemented for considering the high cost of spraying and environmental pollution.
Materials and Methods: In this study some commonly insecticides were tested in different doses to evaluate the effectiveness on cockroaches in sewer system. Three treatments including the combination of the insecticide with class B diatomaceous earth, solid silica gel and boric acid were evaluated in manholes of sewer system. In this regard, the Bushehr city was divided into ten clusters based on its sewer system and then, ten manholes were selected randomly from each area to survey and conduct field experiments. A random-cluster sampling method was used to generalize the results of the whole system. The mortality rate was corrected on control mortality with the Henderson-Tilton formula.
Results: Experimental insecticides spraying controlled up to 100 percent of cockroaches in the laboratory. However, using insecticide alone reduced the mortality rate in manholes over time. The results of statistical tests showed that the most effective method in destroying cockroach was the usage of the compounds of insecticide, mineral and non-chemical substances which caused mortality rate more than 90% up to 12 months.
Conclusion: As little as 50 g/manhole of a dust consisting of 5% silica gel, 35% boric acid, 60% diatomaceous earth with a commercial insecticide such as Deltamethrin sprayer provided more than 98% control for 12 months.
H Nik Nejad, H Pasalari, M Yegane Badi, J Abolghasemi, R Ghasem Nejad, M Farzadkia,
Volume 12, Issue 1 (5-2019)
Abstract
Background and Objective: Clinics, laboratories and health care centers are considered as one of the main waste generating sources in solid waste management. The problems associated with the generated health-care waste in clinics, laboratories and health care centers have been rarely investigated in Iran. Therefore, the present study was developed to investigate the status of health care waste in clinics, laboratories and health care centers of Mahmoudabad, Mazandaran in 2017.
Methods and Materials: This cross-sectional study was conducted to determine the status of solid waste management in 117 medical centers in Mahmoudabad, Mazandaran, 2017. The solid waste data in terms of waste generation rate, storage, collection, and disposal were surveyed through interview and questionnaire that were validated by Iran’s ministry of health.
Results: The average health-care waste generation in medical centers in Mahmoudabad was found to be 248 g/day. The mean and standard deviation for environmental health criteria in all medical centers were 248.3 and 41.1, respectively. In addition, there was a statistically significant difference between the amount of waste generation in private and governmental medical centers (p=0.111).
Conclusion: The results obtained from the present research indicated that the medical waste management in Mahmoudabad, particularly in private centers, face serious problems. Improper waste collection technology, mixing municipal and medical waste, requirement for training the personnel in medical waste management and surveillance can be considered as important concerns in health-care waste management in Mahmoudabad.
E Hassani Moghaddam, Ar Bazdar, M Shaaban,
Volume 12, Issue 1 (5-2019)
Abstract
Background and Objective: Nitrate is one of the most important factors in determining the quality of vegetables. Today, due to the excessive use of nitrogen fertilizers to accelerate vegetative growth, many vegetables have a high percentage of nitrates in human diet. The purpose of this study was to investigate the concentration of nitrate in four vegetable species cultivated in Poldokhtar and Khorramabad cities.
Materials and Methods: In this research, the nitrate content of four vegetables including Iranian leek, Basil, Mint and Radish (tuber and leaves) cultivated from olericulture field on Khorramabad and Poledokhtare were measured. A 2kg edible portion of vegetables was randomly collected for each species in triplicate and carried out to the laboratory. The nitrate content was measured according to the instructions of the Institute of Water and Soil of Iran. For this purpose, after preparation of the samples, a spectrophotometer was used to measure absorption at 580 nm. The nitrate content in different vegetables was estimated using a standard curve.
Results: The nitrate mean concentration of the studied vegetables from khorramabad city was 27017 mg/kg for Radish tuber, 9500 mg/kg for Basil, 8408 mg/kg for Iranian leek, 98231 mg/kg for Radish leaves and 5450 mg/kg for Mint. The values for the samples taken from Poledokhtare city were 12933 mg/kg for Radish tuber, 9063 mg/kg for Basil, 6708 mg/kg for Iranian leek, 6296 mg/kg for Radish leaves and 5454 mg/kg for Mint (5454 mg/kg). The values were all higher than the recommended doses for consumption. In control field, the nitrate mean concentration were 1586, 1134, 906, 794 and 662 mg/kg for Radish tuber, Basil, Iranian leek, Radish leaves and Mint, respectively. The values were within the range of recommended doses.
Conclusion: The amounts of nitrate measured in 100g of green tissue in Radish tuber, Basil, Iranian leek, Radish leaf and Mint were 7.36, 3.37, 2.74, 2.64, and 1.98 times more than the daily allowance limit, respectively. Given the high nitrate content in the studied vegetables, it is recommended that cautious is taken for consumption of the vegetables and nitrate content of the vegetables produced in Lorestan province in different seasons should be monitored.
A Jonidi Jafari, F Ghorbannezhad, A Rastegar,
Volume 12, Issue 2 (9-2019)
Abstract
Background and Objective: Humans are always exposed to ionizing radiation that could potentially have harmful effects. The aim of this study was to evaluate the background gamma dose rate, the estimated annual effective dose, and the excess cancer risk assessment in Dargaz.
Materials and Methods: This study was a cross sectional study which was conducted in January- March and July – September 2016. In this study, 5 stations (4 in the main geographical directions and 1 in the center city) were selected based on the map of the city to determine the dose rate of background gamma radiation in outdoor areas. A dosimeter was used (Geiger Müller detector STEP OD-02 with sensitivity of 0-2000 mSv/h) to measure gamma rays. The device was designed to monitore X-rays, gamma rays and beta rays.
Results: The results showed that the maximum and minimum mean values of background gamma dose rate were 147±12 nSv/h and 113±11 nSv/h in the center and west-direction of the city, respectively. The annual effective dose for Dargaz residents in outdoor was determined to be 0/15 mSv/yr, and the amount of excess lifetime cancer risk was estimated as 0.6×10-3.
Conclusion: The results indicated that there are significant differences between the rates dose in the center and other parts of the city (p≤0.05).
Z Farahbakhsh, A Akbarzadeh, P Amiri, A Naji,
Volume 12, Issue 2 (9-2019)
Abstract
Background and Objective: Heavy metals enter to water resources through various ways, causing dangers such as illness, cancer, and, in general, a disorder in the body of living organisms. Mullet (Liza aurata) is highly consumed by the people living in Guilan province, Iran. Therefore, the amount of heavy metals included copper, zinc, and nickel was investigated in the muscle tissue of mullet.
Materials and Methods: A total number of 11 mullet were obtained from Bandar Anzali. After a preparation step, the fish samples were digested using chemical digestion, and the amounts of heavy metals were determined by atomic absorption.
Results: The average concentration of copper, zinc, and nickel in muscle tissue was 10.07±0.93, 28.39 ±3.99, and 4.01 ± 0.55 μg/g dry weight, respectively. The concentrations of the studied metals were lower than the FAO, WHO, FDA, NHMRC and UKMAFF international standards, except for the nickel. The daily absorption rates of the studied metals (EDI) for children and adults were lower than the reference dose set by the EPA and the TI provided by the FAO / WHO Organization. The risk potential (THQ) of seven days, three days and one day consumption per week of Golden grey mullet for both adults and children were found less than 1. The hazard index (HI) of 7 days a week consumption of mullet for children was greater than 1.
Conclusion: According to the results of the present study, the consumption of this fish has a harmful effect on consumer health in children age group.
K Naddafi, A Mesdaghinia, M Abtahi, Ms Hassanvand, R Saeedi,
Volume 12, Issue 2 (9-2019)
Abstract
Background and Objective: Environmental burden of disease (EBD) studies are one of the most important needs for determining the current situation, increasing the effectiveness of health policies and programs and prioritizing environmental health interventions. This review article was evaluated the status of the EBD in Iran based on the results of the latest Global Burden of Disease (GBD) Study, other international studies and national estimates in the country.
Materials and Methods: In this study, the researches on the EBD in Iran were identified by searching in the international and national scientific databases and the search results were studied and analyzed.
Results: The review of the EBD studies showed that based on the results of the GBD study, the share of environmental risk factors in the total burden of diseases in the country in 2017 according to the disability-adjusted life years (DALYs) and deaths were about 8 and 13%, respectively. According to the results of the GBD study, the contributions of environmental risk factors in the attributable DALYs in the country in 2017 (a total value of 1,648,329) were as follows: ambient air PM2.5 for 45.0%, occupational risk factors for 25.1%, exposure to lead for 19.4%, unsafe water source for 5.0%, tropospheric ozone for 1.7%, lack of access to handwashing facility for 1.5%, unsafe sanitation for 1.4%, residential radon for 0.6%, and household air pollution from solid fuels for 0.3%. The total DALY rate and death rate attributable to solar ultraviolet radiation in Iran in 2000 were estimated to be 46.2 and 0.7, respectively. The DALY and the DALY rate attributable to elevated levels of fluoride in drinking water due to dental fluorosis in the country in 2017 were 3,443 and 4.14, respectively. The evaluation of the effect of water fluoridation as an environmental protective factor showed that the intervention by reducing the risk of dental caries could fall the DALY and DALY rates in the country by 14,971 and 18.73, respectively. In the period of 2005-2017, the DALY rate (per 100,000 people) attributable to ambient air PM2.5, tropospheric ozone, residential radon, and occupational risk factors rose that the result increases the importance of the preventive measures and controls of these risk factors.
Conclusion: There was a considerable difference in the burden of disease attributed to each risk factor in various international studies as well as between national and international studies. The results of national studies on the burden of diseases attributable to environmental risk factors are considered to be more reliable and practical due to the application of more detailed data and conducting subnational evaluations; therefore, the strengthening and continuing these studies at the national and sub-national levels with regard to priorities, needs, and spatiotemporal trends using domestic reliable data and information are necessary and strictly recommended.
K Jafari, N Hafezi Moghaddas, Ar Mazloumi, A Ghazi,
Volume 12, Issue 3 (12-2019)
Abstract
Background and Objective: Groundwater resources are the most valuable resources of each country. Development of agricultural activities in Ardabil plain and over-use of fertilizers and pesticides, improper disposal of municipal sewage and industrial areas are responsible for groundwater pollution. Clean-up of groundwater resources is very difficult and expensive. One of suitable method in preventing groundwater contamination is determination of the vulnerable zones of an aquifer to manage water resources and sustainable development.
Materials and Methods: In this study for determining of vulnerability of aquifer Ardebil, information of 52 observational wells, 43 pumping tests, average of annual precipitation of 8 stations, 45 logs of exploration wells, land use map, topographic map and geological map have been gathered. Then, data layers of groundwater depth (D), Recharge (R), Aquifer media (A), Soil media (S), topography (T), impact of vadose zone (I) and hydraulic conductivity of aquifer (C) were prepared and overlaid based on DRASTIC method in ArcGIS software.
Results: Zoning map of DRASTIC method showed that DRASTIC index varied between 63 to 195 units. Areas with high vulnerability potential were characteristic with shallow depth groundwater, coarse-texture soil, thin soil and gentle topographic slope. Accuracy of the zoning map was evaluated by nitrate concentration map which showed the increase of DRASTIC index with nitrate concentration.
Conclusion: Northwestern and central parts of the Ardabil plain showed high vulnerability. The results of this study could help to reduce the environmental impact of contaminants on groundwater resources of the study area in future.
Kh Faraji Mahyari, Sh Rafiee, Ar Keyhani, Z Faraji Mahyari,
Volume 12, Issue 3 (12-2019)
Abstract
Background and Objective: Knowledge about the quantity of municipal solid waste (MSW) generation plays a key role in formulating policies of waste management. So far, different methods have been applied to estimate the quantity of waste generation. In this study, eight specific forms of mathematical functions were evaluated to predict waste generation by the regression analysis method based on population.
Materials and Methods: The significance test of each model and the existence necessity of predictor parameters were performed using the F- and t-statistic, respectively. The statistical indicators of determination coefficient ( ), adjusted determination coefficient ( ), root mean square error (RMSE), mean bias error (MBE) and mean percentage error (MPE) were used for model’s goodness of fit. The predicted determination coefficient ( ) was calculated to assess the predictive ability of models by method of Leave-one-out cross validation.
Results: The results showed that polynomial models of second order and more are not significant (at 0.01 level) despite good accuracy and are not suitable for long-term prediction. Linear, power and exponential models are best with equal to 0.942, 0.932 and 0.936 and equal to 0.904, 0.893 and 0.898 respectively. However, the uncertainty was greater in the exponential model.
Conclusion: The status of waste generation was investigated in four scenarios based on growth rate of population (increasing, fixing and decreasing births) at Tehran metropolis in 2021-2051. In all scenarios, annual generation and per capita of waste are increased to 2051. The daily waste generation will increase to 12317 ton in 2051.
Alireza Mohaghegh, Mahdi Valikhan Anaraki, Saeed Farzin,
Volume 13, Issue 1 (4-2020)
Abstract
Background and Objective: In the present study, EC and TDS quality parameters of Karun River were modeled using data-mining algorithms including LSSVM, ANFIS, and ANN, at Mollasani, Ahvaz and Farsiat hydrometric stations.
Material and Methods: Eight different inputs including the combination of Cl-1, Ca+2, Na+1, Mg+2, K+1, CO32-, HCO3, and SO42- with discharge flow (Q) were selected as non-random and random calibration inputs for these algorithms. Then, in order to guarantee the accuracy of the results, the simulation was performed by random calibration and the results of the two methods were compared. In the next step, the EC and TDS parameters were modeled based on the four parameters of Na+1, Cl-1, Ca+2, and Q and a lag time of zero to three months.
Results: Modeling results indicated that Na+1, Cl-1, and Ca+2 have the highest influence on modeling of EC and TDS parameters. The LSSVM algorithm was the most accurate in modeling EC and TDS parameters. Among the studied stations, the highest precision for EC and TDS modeling belongs to Ahvaz and Mollasani station, which has 16% and 36% higher coefficient of determination. LSSVM has highest accuracy in modeling the oscillation and peak EC and TDS parameters in during times.
Conclusion: The methods and models applied in the present study especially the LSSVM algorithm, can be a useful decision-making tool for predicting and qualitative management of rivers, including rivers in the Karun catchment area. The results of modeling the quality parameters of the rivers were reliable and usable by using both non-random and random calibration methods. However, the accuracy of the random calibration method was slightly higher.
Akram Fatemi Ghomsheh, Sareh Nezami,
Volume 13, Issue 1 (4-2020)
Abstract
Background and Objective: Much of the nitrate consumption by humans in the daily diet comes from vegetables. The high concentration of nitrate in edible parts of vegetables causes toxicity, anemia for children and nitrous amine production in adults. Nitrous amine may results in cancer. Samples were collected from four main vegetable markets in Kermanshah city in summer 2019 to investigate the concentrations of these compounds in edible vegetables with high consumption.
Materials and Methods: After preparation of the samples in a laboratory, the nitrate were extracted and its concentration was determined by a spectrophotometer at wavelength 410 nm.
Results: The results showed significant differences in nitrate concentrations for the vegetable samples taken from the different markets (p>0.05). The highest concentration of nitrate were observed in the leafy, tuberous, and fruit-bearing vegetables. The highest nitrate concentration among the leafy vegetables was observed in cress with an average of 2052.14 mg/kg Fresh Weight; among tuberous vegetables was potato with an average of 127.01 mg/kg Fresh Weight; and among fruit-bearing vegetables was cucumber with an average of 37.20 mg/kg Fresh Weight.
Conclusion: The nitrate concentrations for celery, and red onion at the Azadi market were higher than the permissible limit, according to the national standard. Also, the nitrate concentrations in sugar beet leave and potato at the Toopkhaneh Market and nitrate concentration in cress at all the markets were higher than the permissible limit. It is recommended that the concentration of nitrate of edible vegetables should be determined at regular time intervals as well as during different seasons.
Reza Nazarpoor, Masumeh Farasati, Abolhasan Fathaabadi, Mohamad Gholizadeh,
Volume 13, Issue 1 (4-2020)
Abstract
Background and Objective: Synthetic wetlands are engineering systems that use natural plants, soils and organisms to purify municipal polluted water and remove nitrate.
Materials and Methods: In this study, three systems were considerd as soil culture, three systems as plant cultivation on floating plates and three other systems without plant and porous bed as. The experiments were done three times within six months. The hydraulic retention times were 1, 3 and 5 days. The experimental design consisted of a factorial split-plot design. The analysis of variance showed that the efficiency of nitrate removal was affected by the type of constructed wetland, HRT, and temperature changes (p≤0.01).
Results: At the HRT of 1 day, the average efficiency of nitrate removal by the soil culture, plant cultivation on floating plates and control were 14.34%, 12.09% and 10.51%, respectively. At the HRT of 3 days, the average efficiencies were 17.62%, 15.76% and 13.54%, respectively. At the HRT of 5 days, the efficiencies were increased and they were 17.75%, 17.66% and 16.08%, respectively.
Conclusion: The results showed that the soil culture were more efficinet in removing nitrate .Also, the Cyperus alternifolius plant has the potential of nitrate phytoremediation.
Sahar Rostami, Farhad Darvishi Se Talani,
Volume 13, Issue 3 (11-2020)
Abstract
Background and Objective: Nowadays, the development of green entrepreneurship plays an important role in sustainable employment, reducing environmental issues, economic development, and moving towards sustainable development. Thus, the present study has been carried out aiming to identify and analyze the factors facilitating the green entrepreneurship process in the field of urban waste using a mixed (quantitative-qualitative) method.
Materials and Methods: The present study was carried out with a mixed approach (exploration projects). For this purpose, using theoretical sampling logic, 14 experts were selected by snowball technique and the required data were collected through semi-structured in-depth interviews to achieve theoretical saturation. In the quantitative section, data were collected through interaction questionnaires handed out to 26 experts who were selected through purposive sampling, and the integrated DEMATEL-ISM technique was employed to build a regular hierarchical structure.
Results: Layer-by-layer model was displayed in 4 levels using DEMATEL-ISM technique. The first layer consists of improving laws and regulations and designing a suitable landscape as the most infrastructural, the second layer includes improving infrastructure issues, expanding supportive issues, culturalization and increasing public awareness, the third layer includes exploiting the potentials of the region and attracting private sector participation, and the fourth layer comprises of entrepreneurial management.
Conclusion: The results show that the first step in creating a facilitator environment for green entrepreneurship process in the field of urban waste is to improve the macro structures that should be facilitated mainly by the central government, the second step is related to the proper infrastructure and preparation of public space governing the society. In the third step, it was found that the development and utilization of the region’s potential increases its operational effectiveness. Finally, with entrepreneurial management, all activities that occurred at previous levels can be used effectively.
