Showing 7 results for Askari
A.r Rahmani, M Solaimany Aminabad, Gh Asgari, F Barjasteh Askari,
Volume 3, Issue 4 (8 2011)
Abstract
Backgrounds and Objectives: High level of nitrate ion in the water resources cause some health and environmental problems. The aim of this research is to study nitrate removal by Zero-Valent Magnesium (ZVM) and MgCl2-modified pumice from aqueous solutions.
Materials and Methods: The pumice granules were modified by MgCl2 . The removal of nitrate was studied in a batch system. The pH, initial nitrate concentration and sorbent mass parameters and the Langmuir and Freundlich models were studied in the sorption of nitrate onto the pumice. The ZVM was also used in a bach system and the previous parameters were studied.
Results: The removal efficiencies of nitrate by ZVM at the the initial pH of 3, 5 and 7 with controlling the pH were 70%, 40% and 30% ,respectively. These values are much higher than the values of the condition during which the pH was not controled. The nitrate removal efficiency increased by increasing of initial nitrate concentration in a constant molar ratio of Mgo/NO3. The removal efficiencies of nitrate by the modified pumice at the the initial pH of 3, 6.5 and 10 (when pH kept under control) were 49%, 29% and 16%, respectively. By increasing of the initial nitrate concentration the removal efficiency increased. The values of R2 for the Langmuir and Freundlich models were 0.944 and 0.810, respectively. The sorption process Fitted well the Langmuir model with a monolayer sorption capacity of 0.68 mg/g.
Conclusion: The modified pumice had lower efficiency than ZVM in the removal of nitrate ion and its usage is not considerably affected bye the pH in comparison with ZVM. The pH of the solution should be cansiderd as a main controling parameter to get an optimum efficiency in the nitrate-ZVM process.
A.r Rahmani, F Nazemi, F Barjasteh Askari, H Almasi, N Shabanloo, A Shabanloo,
Volume 9, Issue 1 (6-2016)
Abstract
Background and Objectives: Phenol is a toxic and persistent substance in the environment. The aim of this study was to evaluate the performance of silica aerogel synthesized using sodium silicate in the adsorption of phenol from aqueous solutions.
Material and Method: Silica aerogel was prepared by Sol-Gel process. The influence of effective variables such contact time, initial pH of the solution, adsorbent dose, and initial phenol concentration on the adsorption efficiency was investigated. The characterization of prepared silica aerogel and confirmation of phenol adsorption was determined through SEM, XRD analysis and NMR, FTIR spectra respectively. The adsorption data was evaluated via Langmuir and Freundlich isotherms and pseudo-first and pseudo-second-order kinetics.
Results: This research found that the phenol adsorption efficiency increased by increasing pH from 3 to 11, so that after 60 min, the absorption efficiency at the 100 mg/L initial phenol concentration and 0.5 g adsorbent obtained 84 and 96.4 % at pH 3 and 11, respectively. The SEM image and XRD patternof synthesized silica aerogel confirmed the creation of porous and amorphous structure. After the phenol absorption, the NMR and FTIR spectra of silica aerogel, confirmed the creation of new bands because of phenol molecule at the adsorbent structure. The absorption of phenol was compatible with Freundlich isotherm and pseudo-second-order kinetic. The maximum absorption capacity (qm) obtained was 47.39 mg/g.
Conclusion: Silica aerogel as an adsorbent, due to special characteristics in the structure and usage, can be a promising treatment process for adsorption of toxic and persistent substances.
N Naqshband, M Askari Hesni,
Volume 10, Issue 2 (9-2017)
Abstract
Background and Objective: Glyphosate is a non-selective, systemic herbicide that can control most plants, but it has harmful effects on organisms, especially aquatic animals. Static bioassays were made to determine acute toxicity of glyphosate and its effects on haematological parameters and behavior changes of common carp (Cyprinus carpio).
Materials and Methods: Common carp were exposed to different concentrations of glyphosate (5, 10, 20, 30 and 40 mg/L) and a control group for 96 h. After that, blood and plasma factors were measured in blood samples. Mortality rate and fish behavioral were recorded during the experiments. LC50, LOEC, NOEC and MATC were calculated by Probit software according to mortality rate in any treatment.
Results: In the early period of the experiment, fish in toxic media were jumping in water and showed high movements. Then after, the behavior such as breathing in surface, loss of balance, weakness and finally death were observed in the different treatments. LC50 value and 95% confidence limit of glyphosate in 24, 48, 72 and 96 h were 36.09, 30.46, 21.78 and 20.05 mg/L for common carp, respectively. The LOEC, NOEC and MATC were calculated as 6.66, 4.73 and 2.005 mg/L. The Significant changes that were observed in blood factors included RBC, WBC, Hct, Hb and plasma factors such as total protein, glucose, cortisol and other factors when the pesticide concentration was increased (p<0.05).
Conclusion: Results showed that glyphosate had a high effect on common carp and it its physiology and immune system. Haematological parameters may be used as an environmental health diagnostic test and stress indicator for agriculture pesticides in aquatic ecosystems.
Ar Mesdaghinia, S Nasseri, M Hadi, E Iravani, M Askari,
Volume 10, Issue 4 (3-2018)
Abstract
Background and Objective: Supply of safe drinking water to each community is one of the most important challenges in improving the general community’s health. Considering the importance of the research on water quality, identification of water quality research gaps was performed by reviewing the relevant studies through a systematic review for Iran.
Materials and Methods: In this study 638, 166, 300 and 1000 relevant articles were found on Scopus, SID, Magiran and Iranmedex databases, respectively. Out of 2104 articles, 1394 articles were excluded from the study. Finally, 710 articles were further reviewed.
Results: Monitoring of pollutants by a descriptive study was the main objective of the most studies (36.62%). Around 13% of the studies were performed on a laboratory scale. Organic pollutants in Iran have been concerned only in 17 provinces, and other provinces have not participated in this regard. Nitrate is studied in around one fifth of the total studies. Heavy metals were also considered as a parameter of concern in the studies carried out on monitoring drinking water resource quality.
Conclusion: This study reflects the research gaps and provides a basis for prioritizing water quality research in Iran. More actions and sound planning should be taken to monitor organic and inorganic pollutants. Chemical and microbial risk assessment, tracing the fate of pollutants and assessment of their ecological effects, investigations on advanced water purification processes, the use of bioremediation methods, identification of biological contaminant using biomarkers and molecular identification techniques are the most important research priorities that require more investigations.
M Kalhor, S Ghaleh Askari, M Bozorgi,
Volume 11, Issue 3 (12-2018)
Abstract
Background and Objective: Concentration prediction with Gaussian dispersion models is highly sensitive to meteorological data. The lack of sounding data station in developing countries may lead to large error and uncertainty in air pollution modeling results. In this paper, the effects of estimated upper air data on the model output concentration values were investigated.
Materials and Methods: AERMOD model was executed once with real upper air data and also with estimated upper air data separately. T-Student and LEVENE tests were used to evaluate the significant differences between concentrations in two modes of using actual and estimated upper air data.
Results: The results showed that large differences in concentration between the two methods. In long term modeling, there was up to 33% differences between real and estimated upper meteorological data and up to 63% differences for short term modeling. A large difference was also observed between boundary layer parameterization values in each case. The statistical analysis showed a meaningful difference (p=0.00) between the cases. The differences between ZICNV, DT/DZ, W* were 7.1%, 48%, and 19%, respectively.
Conclusion: The use of estimated upper meteorological data in comparison with measured data may lead to a large error. The AERMOD modeling results with estimated meteorological data must be expressed with appropriate uncertainties and confidence interval.
Mehrnoosh Abtahi, Mahmood Alimohammadi, Reza Saeedi, Ramin Nabizadeh, Masoomeh Askari, Babak Mahmoudi, Maryam Ghani,
Volume 14, Issue 2 (9-2021)
Abstract
Background and Objective: The aim of this study was to evaluate the chemical and microbial quality of bottled water in Iran and to calculate the water quality index (WQI).
Materials and Methods: Different brands of bottled water (4 samples from 71 brands) were randomly collected from the market. Chemical and microbial characteristics of the samples were examined and determined. Finally, the calculations related to the WQI index were performed and the water samples were classified as excellent, good, poor, very poor and unsuitable.
Results: None of the samples exhibited concentration of heavy metals beyond Iranian water standards, and the concentration of sulfate (SO4), chloride (Cl) and fluoride (F) did not exceed international standards. However, in some samples, nitrite (NO2) and nitrate (NO3) concentrations were higher than recommended standards. With Regard to other water quality parameters, 8% to 89% of the samples exhibited concentration higher than the values provided on the water bottle label. 5 species of different bacteria were found in 15 water samples. According to the WQI index, about 63% of the samples were of excellent quality. Also, the water quality of 34% and 3% of the samples fell in good and poor quality categories, respectively. None of the bottled water samples was of very poor quality.
Conclusion: The quality of bottled water investigated in this study was generally suitable, but due to the wide range of bottled water in Iran based on brand and seasons, continuous evaluation of water treatment methods in companies and careful monitoring of chemical and microbial quality of bottled water in all seasons is recommended.
Afsaneh Askari Zade Haghighi, Samaneh Abolli, Mahmood Alimohammadi,
Volume 15, Issue 1 (4-2022)
Abstract
Background and Objective: barbershops are one of the most important public places for beauty activities, which requires attention to health issues (personal and environmental), and non-compliance with health standards and procedures can be a threat to public health. The level of awareness and performance of employees can affect the management of waste production. This study aimed to investigate the level of knowledge of personnel about waste production and performance in southern Tehran in 2021.
Materials and Methods: This descriptive cross-sectional study was conducted in southern Tehran with a statistical sample of 330 places. In this study, a questionnaire was used which comprised of three sections; demographic information, the level of awareness and performance of personnel, and the information was completed after interviews with hairdressers. Data were analyzed by Kolmogorov-Smirnov, Chi-square, Pearson correlation coefficient, one-sample t-test, and Mann-Whitney using SPSS software (IBM-v.26).
Results: The average scores of awareness and performance of individuals in waste management were 43.18 and 48.27, respectively, and based on the results of qualitative analysis, the scores of awareness and optimal performance of individuals in waste management were 53.6% and 72%, respectively. Also, 46.6% and 28% of the participants obtained unfavorable scores on knowledge and practice in waste management, respectively. People's knowledge about the management of waste produced in hairdressers had a significant relationship with gender, history of health education, history of health crimes, education and performance of people about the management of waste produced in hairdressers with gender and history of health education. There was no significant relationship between knowledge and practice with other variables.
Conclusion: Barbershop is a place where paying attention to environmental health is effective in promoting community health and disease control. Ignoring this issue can lead to the spread of various diseases. In general, the results of this study showed that the level of awareness is effective in the performance of barbers regarding the management of waste production. Additionally, health education was known effective in the level of awareness and performance of hairdressers in this field, so the improtant roles of these variables should taken into consideration.
