فهرست مطالب akram ghorbani

The aim of this study was to investigate the emission of heavy metals (cadmium and lead) in the soil around Taybad landfill. For this purpose, 15 stations at a distance of 100 meters from each other to the landfill of Taybad city were selected for sampling. Sampling 5 samples and repeating 3 times from each station, the samples were transferred to the laboratory for analysis to check the level of pollution indicators. Hypotheses were analyzed using one-sample t-test and Pearson's correlation coefficient with spss 24 software. It was found that the average total concentration of lead is equal to 52.04 and the average total concentration of cadmium is equal to 1.748. The concentration of the mentioned metals is significantly higher than the average global soil and earth's crust with 95% confidence. In the case of lead and cadmium, the highest contamination was in station 10 and 4, and the lowest contamination was in station 6 and 12, respectively. It is concluded that the amount of soil contamination does not change significantly with increasing distance, because the volume and concentration of contaminant runoff from the landfill (contaminant) along the path is constant. Therefore, it is better to provide environmental training for municipal municipal personnel and citizens of the region and to invest in the restoration of the environment and its further protection.

Distribution of heavy metals in all types of sediments is one of the important and new topics in environmental sedimentology. This study was conducted with the aim of investigating the amount of factor pollution, concentration of cadmium and lead metals, geochemical accumulation index and ecological risk category in the soil downstream of Taibad Landfill.

15 stations were selected at a distance of 100 meters from each other and along the waterway exiting the site from a distance of 100 to 1500 meters. After sampling 5 samples and repeating 3 times from each station, the samples were taken to the laboratory for analysis.

In stations 2 and 6, because the pollution factors (CF) are between 1 and 3, the level of pollution in these stations is average, in station 10 it is very high, and for the rest of the stations, because the pollution factors are between 3 and 6, the level of pollution is high. For cadmium metal, the pollution factor (CF) in all stations is between 3 and 6 and the pollution is high. Based on the results, the amount of lead and cadmium metals in the risk category They are ecologically average.

The amount of lead metal pollution in station 2 and 6 is moderate, station 3 is very high and in other stations it is high. Cadmium metal contamination was reported in all stations. Both metals are in the medium category in terms of ecological risk.The concentration mentioned metals in the soil downstream of the landfill is significantly higher than the global soil average and the earth's crust. It seems that this pollution is caused by the landfill, which was spread to the downstream lands by seasonal runoff

Air pollution is one of the important environmental problems in the modern world. Sources of air pollution are various and variable. the share of air pollution resulted from vehicles traffic finds importance increasingly and has become an important environmental and health issue. It has been announced that around 80 percent of air pollution is related to the mobile sources, and to control and reduce air pollution, the priority should be assigned to vehicles, particularly heavy and public vehicles. Despite the many advantages that made diesel engines used in the past for various purposes and in various types of vehicles, their use for passenger car propulsion has faced problems that have prevented their large production in this field. The most important of these problems are: more noise and vibration than gasoline cars, bad smell of diesel when refueling, emission of gas and visible smoke from the exhaust, higher price than gasoline cars, low acceleration and speed, and bad starting in cold weather. Despite these problems, these cars are still very popular due to their economical fuel economy.Researchers have identified a significant relationship between the amount of air pollution, respiratory diseases and cardiovascular diseases, which have a special importance in the admission rate of hospitals in metropolitan cities. Therefore, according to the small number of studies conducted in the field of the effect of emissions caused by diesel cars in the field of air pollution, the purpose of the current study is investigating the amount of exhaust emissions of diesel vehicles and the relationship between such amounts and the life of the vehicle, in the city of Mashhad.

In the current study, in order to investigate the amount of exhaust emissions of diesel vehicles among all vehicles of this type throughout Mashhad, which were 5861 vehicles, 425 vehicles were selected randomly. The diesel vehicles used in the present study included garbage trucks, buses, minibuses, garbage Nissan Junior, Isuzu garbage truck, Dongfeng irritation truck, HOWO irritation truck, garbage Hyundai truck, irritation Benz truck, sweeper vehicles, irritation Volvo truck, garbage Amico truck, Fh12 irritation truck, Kavian garbage truck.The sampling of the study was carried out continuously from December 6, 2017 through April 29, 2018 (except for 1st to 4th of Farvardin Iranian Month), from 9 a.m. to 12 p.m. and 15 p.m. to 20 p.m.Sampling was conducted by the five-gas detector (NDIR OPTIM7), the model of which was MRU, and it was made in Germany. Sampling was conducted when the engine was idling. Before the experiments, the device was tested and calibrated by the maker. The gases measured by the five-gas detector included HC, CO2, CO, O2 and NOx. The device is connected to the compute by Bluetooth and it includes a software program by which it is possible to run and test the device and observe and record the amount of pollution. The device used in the current study was calibrated by the relevant manufacturing company, before the experiments.Finally, after collecting data, they were analyzed by SPSS (version 20) statistical software. Considering that the variables were not normalized, the Kruskal-Wallis Test was used. Given the significance of Kruskal-Wallis Test, the post hoc test relevant to the Kruskal-Wallis Test, meaning the Dunn's Multiple Comparisons Test, was used, which is calculated by the Prism software. Moreover, In order to draw diagrams, the Excel software was used.

A comparison of the average CO emissions among different groups of vehicles:The highest amount of CO pollutant emissions is related to the sweeper vehicles. The minibuses are in the second place, heavy vehicles in the third place, semi-heavy vehicles in the fourth place and the lowest amount of CO emissions is related to the buses. Considering the post hoc test conducted, there is a difference between semi-heavy vehicles and sweeper vehicles, in terms of CO. considering the obtained results, it might be concluded that the fuel combustion in sweeper vehicles occurs in a more incomplete way compared to the semi-heavy vehicles. A comparison of the average HC emissions among different groups of vehicles:The highest amount of HC pollutant emissions is related to the minibuses. The heavy vehicles are in the second place, sweeper vehicles in the third place, buses in the fourth place and the lowest amount of HC emissions is related to the semi-heavy vehicles. The highest amount of HC pollutant is related to the minibuses, which is probably due to the low density or improper spraying of injectors; however, by modifying the geometric shape of the combustion chamber and the piston head at the time of combustion and density, the ratio of the mixture of air and fuel or turbulence increases, the result of which is complete combustion with minimum amount of CO and HC polluting gases. A comparison of the average CO2 emissions among different groups of vehicles:The highest amount of CO2 pollutant emissions is related to the buses. The minibuses are in the second place, sweeper vehicles in the third place, heavy vehicles in the fourth place and the lowest amount of CO2 emissions is related to the semi-heavy vehicles. As seen in the current study, buses, compared to other vehicles, produce the highest amount of CO2 and the lowest amount of CO, which indicates complete combustion in them. A comparison of the average NOX emissions among different groups of vehicles The highest amount of NOX pollutant emissions is related to the minibuses. The buses are in the second place, heavy vehicles in the third place, semi-heavy vehicles in the fourth place and the lowest amount of NOX emissions is related to the sweeper vehicles. by using the system of exhaust gas recirculation on the engines with the TIER3 emission standard, the temperature of gases exiting the exhaust becomes normal and as a result, the amount of NOX emissions from the exhaust decreases. However, when the engine runs at a high speed and under high load, the temperature rises at the time of combustion, and as a result, the temperature of the gases exiting the exhaust rises, too, and consequently, the amount of NOX increases.

80% of air pollution in urban areas comes from heavy vehicles. The purpose of this study is to investigate the amount of CO2 , CO, HC, NOX pollutants, types of diesel cars and their relationship with the life of the car.

In this study, out of all diesel cars in Mashhad, which is 5861 cars, 425 cars were randomly selected and after recording the year of car production, using OPTIMA7 NDIR five-gas pollutant device in bright engine mode (Engine operation). Sampling was performed continuously (except for the first to the fourth of April) in the period of December 6, 2017 to May 9, 2017 at nine to twelve and fifteen to twenty o’clock and Then, using SPSS software and statistical tests. The relationship between these pollutants and vehicle life was investigated.

According to the amount of sig (p=0/531>0/05) between the life of the car and carbon monoxide, the amount of sig (p=0/571>0/05) between the life of the car and the amount of hydrocarbon, the amount of sig (p=0/153>0/05) between the life of the car and carbon dioxide output and the amount of p=0/290>0/05 (sig) there is no significant relationship between car life and nitrogen oxides. There is an inverse correlation between the car’s year of manufacture and CO2 and NOX pollutants, So that the higher the car’s year of manufacture, the lower the amount of carbon dioxide and nitrogen oxides. And there is a positive correlation between HC and CO pollutants.

The significant level value (sig) between car life and all pollutants is greater than 0.05, so there is no statistically significant relationship between car life and all exhaust gas pollution. Therefore, the amount of air pollution by diesel cars should be reduced by taking correct management methods.

One of the complications of transportation in cities is noise pollution caused by vehicles. Today, noise in urban environments is an important issue in the field of public health. Due to the negative effects of noise pollution on human health and well-being, it is necessary to identify and understand these effects on the health of exposed people. In this study, the type of traffic axis composition of the highway was identified and the type of traffic information required was identified by identifying the locations for the sound station along the highway axis and preparing sound data and identifying the factors affecting sound propagation. At each sampling station, the required variables in the intervals of 7: 30-9: 30, 12: 30-14: 30, 18: 30-20: 30, 23: 30-1: 30 And 3: 30-5: 30 and different seasons of the year were measured and recorded for modeling. The results show that the comparison of the average parameters of noise pollution in different stations of Shahid Kalantari Highway at a significant level of 5% showed that the highest amount of noise and sound indicators measured are related to the first station of Abadgaran with the amount of deci, respectively. Bell is 79.61 dB, the entrance road to Kuhsangi is about 80 dB and the lowest station of Hafez Square is about 58 dB. The parameters Lmax, Leq, L10, L50 and L90 are visually uniform distribution of results in the fit line range. According to the results of this study, it is announced that in all seasons of the year, the average equivalent sound level in all stations studied is higher than the recommended daily ambient sound level in the Iranian open air sound standard. While the standard sound level in residential areas is 55 decibels during the day and 45 decibels at night.

This study aimed to model the noise pollution level in 9th and 11th districts of Mashhad municipality (Vakilabad highway) by using Traffic Noise Model (TNM 2.5). To this end, the equivalent sound level measurement of the 25 high-traffic stations selected along the Vakilabad highway in Mashhad was carried out by the TES-1358 sound level meter, for 6 months and each month for 1 working day in the year’s 2017. Traffic volume data was also measured to level the day by the wood line method and then the total data was introduced to model the traffic noise volume in the area. The assessment of the traffic noise of the study area in the model showed that the average equivalent sound level calculated by the model for the stations measured at Vakilabad highway is 6.51 dB less than the recorded values by the sound meter in the real environment by the average of 78 dB. In addition, the results of this study indicated that the TNM could provide a reasonable prediction of traffic volume and its distribution on the Vakilabad highway in Mashhad, due to providing a similar ranking of areas with low or high noise pollution and also displaying acceptable values of Leq calculated as compared to recorded sound values in the real environment.

This study aims to evaluate and zone the noise pollution level of districts 9 and 11 (Vakil-Abad Highway) in Mashhad, using statistical methods and GIS software. For this purpose, the required sound data were taken from 25 selected high-traffic stations of studied area in spring, summer, autumn and winter during 2016-2017. The process involved 1 full day of work per month for 6 months, from 7:30 AM through 8:30 PM, using a TES-1358 sound level meter. Traffic data and measured sound indicators were analyzed statistically by MSTAT-C, SPSS, and Excel software. After they were inserted into GIS software, the layers of information were obtained to provide the level of noise pollution and its distribution in the area. The comparison between the results and findings at a significant level of 5% indicated that the highest sound levels 85.63, 80.72, 78.10 and 81.46 dB belong to station 20, October, morning time and commercial-residential use, respectively. Day-time zoning maps of Vakil-Abad Highway in Mashhad also showed that the intensity of noise pollution in the central parts of the mentioned region is more than the other parts and can provide an accurate analysis of how the sound is distributed in the desired area. Since the day-time average level obtained for Vakil-Abad Highway is higher than Iran's standard level, serious action may be taken to control the noise and prevent its complications in the region.

Mashhad metropolis as the second largest religioncity in the world and the second largest metropolis of Iran with an annual 3 million pilgrims have significant direct and indirect effects on the watershed leading to the city and surrounding over the past four decades. There is no collection system and sanitation disposal network in towns and villages within the Torghabeh River.   Therefore, in this study the qualitative changes of Torghabeh River from October 2011 to September 2012 at 8 stations during four seasons (autumn, winter, spring, summer) was investigated by sampling of surface waters and measurement of water quality parameters along the river. Data from this study were analyzed using NSFWQI Index and finally was zoning using GIS software. The results showed that the best and worst quality is related to stations 1 and 8, respectively. Moreover, it was found that the autumn season with an average of 46 has the best quality among the studied seasons. However, the worst situation (bad quality) was related to winter season with an average of 39. Finally, it can be concluded that the water quality of Torghabeh River in its different parts is far from the desired level.