Sharif Digital Repository

City of Karaj with 2 million population used to enjoy very clean and accommodating air and environment . This congenial condition was due to agricultural and gardening activities of the local population . This way of life has undergone a profound change due to a change in the economic activities of the local population from farming and agriculture to industrial activities . And this has brought particulate matter wich has been exacerbated in the recent years . With the additional onslaught of the dust storms coming from the neighboring countries due to drying up of rivers and lagoons .The main object of this work was to obtain the spectrum of the PM and the additional component of PM that... 

Environmental conditions of various cities of Iran are deteriorating due to various contributing effects of increased traffic, deforestation, industrial pollution etc. Arak is an example in point. It is a city of about 440,000 inhabitants. It is located at the edge of the main central desert (Kavir) of Iran. It lacks any appreciable vegetation or wooded areas and it is the home of a number of major industries. These include aluminum smelting, petrochemical industry, refinery, power plant and various other heavy manufacturing facilities. It was suggested to perform an air sampling of the city for a whole year (2010-2011) to determine the concentration of various elements by instrumental... 

In the current study, the dispersion of four major air pollutants, sulphur dioxide, nitrogen oxide, carbon monoxide, and particulate matter from gas flares of an oil field, in Iran, was investigated for year 2011 by application of a conventional steady state Gaussian dispersion model, AERMOD. Two scenarios were applied in modeling, first application of flare parameters based on technologies that exist and the other one using new technologies in flares such as steam assisted with better combustion efficiency. Due to the complexity of meteorological parameters in modeling area, CALPUFF model was used in this study. CALPUFF which is a more advanced model that considers the effect of... 

The present study simulates the diffusion of nitrogen oxides from a typical thermal power plant by AERMOD. The amount of diffusion of nitrogen oxides in the environment in two sample days was assessed, one in the cold season and the other in the warm season. In the pessimistic state of the power plant on the sample day of the warm season did not cause the ambient concentration to exceed the standard level of clean air.In order to evaluate the share of different emission sources in the study area, emission sources are divided into three groups: industrial, suburban transportation and urban resources (domestic and intra-city transportation) and two modes of emission are considered. On the... 

Air pollution has been one of the most important problems in Tehran in recent years. So that the number of deaths due to air pollution in Tehran reaches more than 7000 cases per year. More than 75% of air pollutant emissions in Tehran city (including 60% of PM2.5 emissions) originate from mobile sources. Considering the harmful effects and damages caused by air pollutants, it is important to examine and evaluate the effects of hybrid-electric vehicles on the emissions of the transportation sector and air quality, especially in areas with a large population and realized high traffic load. On the other hand, the continuous reduction of renewable electricity production costs makes electricity a...