فهرست مطالب mohammad hassan mahmoudian

Street foods are ready-to-eat foods and drinks prepared and sold by vendors on the streets and other public places for immediate consumption or consumption at other times without any processing steps and are welcomed by a wide range of people for reasons such as the economy and easier access. This study aimed to investigate the status of heavy metals such as lead (Pb), cadmium (Cd), aluminum (Al), arsenic (As), and manganese (Mn) in the most common street foods in Qom City, Iran, (Falafel, shoulders and wings) according to the particular cultural, social, pilgrimage, and tourism conditions of the city.

After preparing and collecting 18 samples of Falafel and 18 samples of shoulders and wings in the summer via quota stratified sampling method from supply and distribution centers in the city, the samples were transferred to the instrumental analysis laboratory of the faculty of health. After crushing, grinding, and weighing 2g of the samples, dry ashing was performed while maintaining the temperature program. White ash was dissolved in 5% nitric acid, and finally, the concentrations of Pb, Cd, As, Al, and Mn in the samples were measured by graphite furnace atomic absorption spectrometry (GFAAS).

According to this study, Mn, Al, and Pb metals had the highest concentrations in falafel, shoulder, and wing samples. Mean concentrations of Al, As, Cd, Pb and As in falafel samples were 10.07±9.82, 0.0005±0.0002, 0.0007±0.0003, 2.65±1.33, 24.50±11.91 µg/g, respectively, and in the shoulder & wing samples 11.12±7.70, 0.0009±0.0006, 0.050±0.018, 1.62±1.24, 18.50±14.64 µg/g, respectively. Also, the concentrations of Al, Pb, and Mn were higher than the standard level in all samples. The results showed that the mean concentration of As and Cd in Falafel, shoulder, and wing samples were less than the standard level.

According to the results of this study, the concentration of aluminum, lead, and manganese in all samples is higher than the standard level; it seems that if the necessary hygienic measures are not taken during the various stages of production and supply of these foods, it will seriously threaten the health of consumers. The usefulness and enjoyment of street food are essential factors in encouraging consumers to purchase this type of food, so with the widespread acceptance of this type of food by society, essential strategies should be adopted by health authorities to create a proper food culture in society by emphasizing the correct understanding of food safety hazards and the quality of food consumed.

Background & Aims of the Study: Pharmaceutical compounds have a variety of forms and applications. Specific amounts of toxic organic compounds in the process of their manufacturing and utilization cause environmental pollution problems. So, degradation and removal these compounds are necessary. The aim of this paper is the study photocatalytic degradation of ciprofloxacin drug in aqueous solution using photo-Fenton process in a batch photoreactor. This is an experimental study on a laboratory scale. Fe2+ ions as a homogeneous catalyst applied for the degradation of ciprofloxacin in aqueous solution. The study was performed on synthetic wastewaters that contain ciprofloxacin as a pollutant. The effect of operational parameters such as pH, Fe2+ concentration and H2O2 concentration on reaction kinetics were studied and the optimum conditions were determined for the photocatalytic degradation of ciprofloxacin using one factor at the time (OFAT) experimental design method. The optimal conditions were obtained at pH =3, Fe2+ concentration at 35 ppm and H2O2 concentration at 25 ppm. A first order reaction with rate constant (k=0.0291 min−1) was observed for the photocatalytic degradation reaction. The chemical oxygen demand (COD) analysis of the ciprofloxacin under optimum conditions showed 92% reduction COD in a 49 min period. The results showed that the photo-Fenton process can be a suitable alternative method to degradation of pharmaceutical compounds from synthesis wastewaters.

Background & Aims of the Study: The quality of the edible oils is made with chemical compositions and percentage of the degree of unsaturation fatty acids. The peroxide value (PV) always measures the extent of primary oxidation (rancidification) of oils. Oils Rancidity can produce potentially toxic compounds associated with health effects such as heart and neurological disorders. In order to investigate initial oxidative rancidity of the oils, PV will be measured. The aim of this paper is determination of PV and the acid number taking place in oils during frying process and its relationship with demographic characteristics and environmental conditions.
In this study, the statistical populations are sandwich and fast food shops of Qom city, Iran. Samples were conducted, using cluster sampling. For data collection, a questionnaire and chemical tests were used. Samples were transferred in the laboratory under cool conditions for PV and acid number (AN) examination. A hundred fifty different sample of oil were collected. Statistical analysis was performed by SPSS. The ANOVA, T-test and Pearson coefficient were used for data analysis.
From the points of view of PV, 80% of oils were consumable and 20% were not. The lowest and the highest number of PV were 0.6 to 16.5, respectively. The minimum and the maximum number of AN were 0.028 to 0.2, respectively. With the assumption of equal variances (p>0.05), a significant relationship between the increase after the age of the chefs and the lack of obtaining a health card was shown. The small correlation between the temperature of the oils and PV, r(150)=-0.21, p=0.009 is shown. There wasn’t seen any relation between the type of oils with PV and AN.
Antioxidants, oil saturation and the reduction of temperature can reduce the production of peroxide; thus, PV was reduced. Due to the results, temperature increasing lead to increases the peroxide content. In this case, 3.3% of the edible oil samples were in rancidity conditions.
This study has indicated that PV in almost sample was lower than the standard amount. However, removing the oil absorbed into the food leads to reducing the peroxide content and other hazardous compounds by fast-food consumers. This survey indicated that some cookers are not completely aware of government regulation and control procedures for PV and AN of frying oils.

Background & Aims of the Study: Nitrate is one of the most important contaminants in aquatic environments that can leached to water resources from various sources such as sewage, fertilizers and decomposition of organic waste. Reduction of nitrate to nitrite in infant’s blood stream can cause “blue baby” disease in infants. The aim of this study was to evaluate the nitrate removal from aqueous solutions using modified almond charcoal with zinc chloride.
This study is an experimental survey. At the first charcoal almond skins were prepared in 5500C and then modified with ZnCl2. Morphologies and characterization of almond shell charcoal were evaluated by using FTIR, EDX, BET and FESEM. Adsorption experiments were conducted with 500 ml sample in Becker. The nitrate concentration removal, contact time, pH and charcoal dosage were investigated. The central composite design method was used to optimizing the nitrate removal process. The results analyzed with ANOVA test.
The best condition founded in 48 min, 1250 ppm, 125 mg/l and 3 for retention time, primary nitrate concentration, charcoal dosage and pH respectively. The results showed that the nitrate removal decreases with increasing pH. Modification of skin charcoal is show increasing of nitrate removal from aquatic solution.
In this study, the maximum nitrate removal efficiency for raw charcoal and modified charcoal was determined 15.47% and 62.78%, respectively. The results showed that this method can be used as an effective method for removing nitrate from aqueous solutions.

Background & Aims of the Study: Studying the phasic process of the biogas yieldis required to optimize the design and operations; it also helps to lower energy production costs by decreasing the capital investment and operational costs. Here we determine the biogas process by measuring pH, ORP, electrical power and make compatibility to the biogas production trend.
In this research, one 1150 ml single chamber reactor is used. Biogas production trend was precisely followed by a probable compatibleness with pH, Oxidation Reduction Potential (ORP), electrical Power at a temperature of 37 0.5˚C with the substrate of cattle manure. The experiment was followed for 120 days approximately.
As a result, the phases of biogas yield could be determined by the measuring of pH, ORP and its compatibility to gas production. In the reactor, hydrolytic, acetogenic and methanogenic phases were occurred in the days 1-7, 8-16 and 17-104, respectively. Also the electrical power at first showed to be produced at high range but by increasing, the production of biogas decreased and then by decreasing the biogas production gradually, it increased slightly.
Our results indicated that the phases of biogas production can be separated completely and by diffracting the phases, the efficiency of biogas production could be increased.

Improvement of education quality of a university depends on the quality improvement of its departments. Therefore, internal evaluation of the department is an effective step in the quality growth of higher education system. The present study was performed aiming at internal evaluation of the Department of Environmental Health Engineering of the Qom University of Medical Sciences in 2010 took place. This study was done using a descriptive cross-sectional method. Four questionnaires, including department manager, faculty members, students, and graduates were used to collect the data. In completing these questionnaires, interviews, observations and review of documents were also done, and they were interpreted and concluded by employing descriptive statistics in the form of frequency distributions and measures of central tendency and dispersion. The scores obtained for the goals and mission, management, and development of the department were 2.2, 2.1, and 2.82, respectively; the ratio of the number of faculty members to students, faculty members’ research activities, and satisfaction of the department were 2.23, 2.1, and 1.12, respectively; the ratio of the number of the students to the existing facilities, and awareness of the goals and missions of the department were 2.1, 1.75, respectively; and the ratio of the courses to the need of the graduates, satisfaction of the educational programs, and satisfaction of the content of the department programs were 1.68, 1.84, and 2.1, respectively. According to the results of this research, there is necessary that university departments attempt to protect and promote the factors, which are in ideal conditions and plan to improve the adverse factors. University officials should provide necessary conditions and resources to improve the present situation and achieve the most desirable level.

One of the major sources of drinking water contamination is nitrate. Nitrate concentrations of more than the standard levels (45mgl-1 based on nitrate) could cause methemoglobinemia in children. The aim of this study is to investigate the nitrate adsorption on granular ferric hydroxide (GFH). Also in this study, the effect of factors such as initial concentration of nitrate, contact time, adsorbent mass and particle size of adsorbent were determined.

This study was conducted in a laboratory-scale in which the synthetic nitrate solutions were placed in a batch reactor, in contact with the adsorbent to model the adsorption kinetics.

The findings of the study indicated that by increasing Nitrate‘s initial concentration, sorption capacity reaches to the maximum level in a short time of two to three minutes. Increasing the amount of adsorbent and decreasing the adsorbent particle size could reduce the adsorption capacity. Also, the absorption kinetics followed the pseudo-degree reaction model.

This removal method could decrease nitrate concentrations to less than the standard level (45mgl-1 based on nitrate). Easy operation and high adsorption capacity of GFH are the advantages of this removal method.