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Showing 7 results for Jamal
Effect of Pretreating Waste Activated Sludge with Ozone on the Performance of Aerobic Digestion Process
G Moussavi, A Jamal, H Asilian,
Volume 1, Issue 2 (10 2009)
Abstract

Background and Objectives: A conventional treatment to stabilize the excess activated sludge is the aerobic digestion process but due to long aeration time, it requires large equipments as well as high investment cost. Because of high oxidation potential of ozone, sludge ozonation enhances stabilization rate and reduces sludge treatment equipment size and cost. Therefore, in this study, the combination of pretreatment with ozone and aerobic digestion processes were investigated.
Materials and Methods: The experimental set-up consisted of an ozone generator and ozonation reactor with the total volume of 2 L. Removal percentages of TSS, VS, total and soluble COD, HPC, fecal coliform and settable solids were measured in integrated process compared to the single ones.
Results: The results of this research indicated that the aerobic digestion of waste activated sludge during 10 days could reduce 38% of volatile solids and thus obtaining the EPA standard. Also, the results of combined ozonation and aerobic digestion revealed that the pre-ozonation at 0.25 g O3/g TS or 0.5 g O3/g TS with 6 or 3 days aeration, respectively, could achieve 38% reduction in VS and hence the requirement set by EPA. Therefore, integration of pre-ozonation with aerobic digestion can significantly reduce the digestion time to attain the standards.
Conclusion: The sludge pre-ozonation with low dose of ozone due to solids disintegration can enhance the efficiency of aerobic digestion in waste activated sludge stabilization, and consequently decrease size of equipments, air requirement, investment and probably operation cost.


Comparative Study of Bottled Water Microbial and Physicochemical Quality with National Standards and its label ( A Case Study in Qazvin City, Iran)
Akbar Eslami, Hamzehali Jamali, Shirin Naderi,
Volume 6, Issue 2 (9-2013)
Abstract
Background and Objectives: Water is essential for sustaining life & adequate safe supplies must be accessible to the public. Nowadays, people prefer to purchase bottled water for reasons including taste, convenience, following fashion, and its safety and sanitary conditions. According to the WHO guideline, it is of great importance to control the bottled water because of keeping it for longer period of time and at higher temperature in comparison with the water of distribution networks, reusing containers and bottles without adequate washing and disinfecting, and more growth of microorganisms having less important in the terms of health. The aim of this study was to investigate the microbial and physicochemical quality of bottled water in the stores of Qazvin City and to compare the aforesaid features with national standards and to check the quality with the bottles label.
 Materials and Methods: In this cross-sectional study, 51 samples of 11 bottled water brands with different production date were obtained. The features were studied in accordance with Standard Methods. Then, the data were analyzed by T-Test and one way ANOVA analysis using SPSS software. Eventually, the results were compared with the national standards, the WHO guidelines, and the product labels.
Results: Results showed lack of microbial contamination of the samples. Physically and chemically, all the parameters measured were below the national standards level. Study of conformity of the variables to the label indicated that mostly there was a significant difference between the values measured and the values listed on the product labels. Conclusion: Although the concentration of microbial, physical and chemical features of samples were in the extent of national standards, there was a meaningful difference between labels and measured values so that the average concentration of TDS, TH, SO4-2, Ca2+, Mg2+ and Na+ would be more than the label values and the average of the other parameters was lower than the label values.
Investigation of Electro-Fenton process in degradation of phenol from aqueous solutions
Alireza Rahmani, Jamal Mehralipoor, Amir Shabanlo,
Volume 7, Issue 2 (10-2014)
Abstract

Background and Objective: Electrochemical methods as one of the advanced oxidation processes (AOPs), have been applied effectively to degrade recalcitrant organics in aqueous solutions. In the present work, the performance of electro-Fenton (EF) method using iron electrodes on the degradation of phenol was studied. Materials and Methods: In this study, a lab-scale EF batch reactor equipped with four electrodes and a DC power supply was used for removing phenol. The effect of operating parameters such as pH, voltage, H2O2 and initial phenol concentration and operating time were evaluated. We added H2O2 manually to the reactor while iron anode electrode was applied as a ferrous ion source. Results: It was found that initial pH of the solution, initial H2O2 concentration, applied voltages were highly effective on the phenol removal efficiency in this process, so that 87% of phenol after 15 min of reaction at pH=3.0, voltage 26 V and H2O2 100 mg/L was removed. Phenol removal efficiency decreased with increasing pH, so that at pH 10, after 15 min, efficiency was 11%. To remove 99.99% phenol at pH 3, 100 mg/L concentration of H2O2 and voltage 26 V for 60 min was required. Conclusion: Electro-Fenton process using iron electrodes for phenol degradation and remediation of wastewater could be a promising process.


Designing a Satisfaction Level Questionnaire for Using in Sewage Collection Network: Evaluation of Validity and Reliability
Rs Hajimirmohammad Ali, H Karyab, Ha Jamali, Mm Emamjome, F Ansari Maleki, A Arezomand,
Volume 9, Issue 4 (3-2017)
Abstract

Improper and incorrect implementation of sewage collection networks can cause environmental and health problems. It also causes dissatisfaction in urban residents. The purpose of this study was to design a questionnaire for evaluating satisfaction level of urban residents from sewage collection network. Face validity index, content validity ratio and Cronbach-coefficient were used to evaluate validity and internal consistency. The evaluated indexes were assessed in acceptable levels. The designed tool that was included 25 variables can be used to assess satisfaction level by researchers and wastewater companies.


A managerial analysis of Iran’s renewable energy development strategies to reduce greenhouse gases and improve health
Sara Ordoo, Reza Arjmandi, Abdolreza Karbassi, Ali Mohammadi, Jamal Ghodosi,
Volume 14, Issue 4 (3-2022)
Abstract
Background and Objective: The present research has been performed to investigate the opportunities and challenges facing the Iran’s renewable energies development to reduce climate change and improve health and represent managerial solutions in power generation sector by SWOT-AHP analysis models.
Materials and Methods: Using literature reviews and survey, the SWOT was applied to identify internal factors includeding strengths (S), and weaknesses (W), and external factors includeding opportunities (O), and threats (T). The strategies were drived to develop renewable energy in Iran. The proposal strategies were ranked by using the SWOT matrix and analytic hierarchy process (AHP) model.
Results: According to the SWOT matrix calculations, total scores of internal and external factors were found as  4.1 and 4.4 of 5, respectively, which show high potentials of internal factors and opportunities. The most importannt factor of strengths (S) was found to be the great potentials of solar energy sources in Iran. The main priority of opportunities (O) is supportive laws to encourage the private sector. The most important weakness (W) was lack of comprehensive knowledge of managers and politicians about the benefits of renewable energy. The main threats (T) were low tendency of private invests, unpredictable inflation in Iran, and low prices for fossil fuels.
Conclusion: The results of this research represent in four categories of SO, ST, WT, WO strategies. The important SO strategy is increasing guaranteed electricity purchase tariffs (GEPTs), and creating the renewable energy market. The most important strategies of ST were establishment of the renewable energy fund and assessment of exporting electricity by the private sector. The most dominant strategy of WT was modifying guaranteed electricity purchase contracts. The strategies of WO were found to be as following; convincing government agencies to provide the necessary infrastructure and support for knowledge-based companies. 
 

Contamination and source apportionment of iron, zinc, cadmium and chromium elements in surface soil of Khorramabad county, Iran
Masoumeh Selahvarzi, Soheil Sobhanardakani, Amir Hooman Hemmasi, Lobat Taghavi, Jamal Ghoddousi,
Volume 15, Issue 4 (3-2023)
Abstract
Background and Objective: Soil contamination with heavy metals is the most important challenge and common environmental, economic, and public health issue in the world. Therefore, this research was conducted to evaluate the contamination and source identification of Fe, Zn, Cd, and Cr in the surface soils of Khorramabad county, west of Iran in 2020.
Materials and Methods: In this descriptive study, after dividing the study area into 11 homogeneous units, a total of 65 surface soil samples were collected. After preparing the samples, the content of the elements was determined using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Also, enrichment factor (EF), pollution factor (CF), and Nemrow integrated pollution index (NIPI) were calculated. Statistical analyses of the data were performed using SPSS statistical software.
Results: The results showed that the average content of Fe, Zn, Cd, and Cr (mg/kg) in soil samples were 3.14, 1.13, 0.021, and 0.529, respectively. The EF values showed that the enrichment of Zn, Cd, and Cr was "extremely severe" and the average values of EF for the elements followed the descending order of Cd > Cr > Zn. The average values of CF and NIPI varied from 3.30×10-5 to 0.182 and 0.043-0.136, respectively, indicating the level of "low pollution" and quality conditions of "no pollution" in all the studied stations. Based on the results of multivariate statistical analysis (PCC, PCA and HCA), Fe has a geological origin; while, Zn, Cd, and Cr mainly originated from a combination of geological processes and anthropogenic activities.
Conclusion: Although the average values of CF and NIPI showed that the study area has an acceptable soil quality, the values of EF indicated the impact of anthropogenic activities on soil contamination. Therefore, regular and periodic monitoring of soil samples as well as management and control of pollutant emission sources is recommended for maintaining environmental and human health.

Evaluation of the implementation of the nosocomial infection control program in the emergency department of teaching hospitals of Gorgan, Iran
Mehrnaz Asghari Mahforujaki, Ailar Jamalli, Saeed Golfiroozi, Ali Shahryari,
Volume 16, Issue 1 (6-2023)
Abstract
Background and Objective: In hospitals, the emergency department is a complex healthcare environment, and it is necessary to attention to nosocomial infections. This study aimed to evaluate the implementation of nosocomial infection program in the emergency department.
Materials and Methods: This descriptive study was conducted in hospitals of Gorgan, Iran, in 2022, using the WHO checklist with 96 questions in 9 section staff; patients, environment, equipment, drug, prevention of infections wound, urinary, respiratory, and blood. Data were collected via observation and interviews. A checklist containing 45 questions was used to determine the impact of staff awareness on the infection control program, in 4 sections oftheoretical knowledge, performing procedures, immunization, and environmental hygiene.
Results: The results show that 82.46% of the infection control program was satisfactory. The percentage of scores for different sections of nosocomial infection program including staff, patients, environment, equipment, drug, infection prevention of wound, urinary, respiratory and blood  was 79.31, 77.78,  81.25,  83.34, 100, 44.34, 75.00, 87.88 and 100, respectively. Moreover, the percentage awareness score for emergency medicine specialists, general practitioners, medical interns, and nurses was 100, 95.83, 87.5, and 79.92, respectively.
Conclusion: The implementation quality of the infection control program was acceptable and satisfactory. However, some factors were lower than the desired level, which could be dangerous for medical staff, patients, and visitors. The medical staff believed that the support of the senior managers of the University was essential for the implementation of an infection control program, and also holding training courses, and accelerating data sharing.
 

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