INTRODUCTION Because of the controversy over air pollution that has erupted in newspapers and magazines during the past several years, most people are aware of the potential hazards associated with air pollutants such as sulfur dioxide, nitrogen oxides, ozone, etc. However, there is another, relatively unknown, type of air pollution which is just as serious, if not more serious, than anything o...

acid rain has been a big problem for urban area during recent decades. acid rain comes from high concentration of air pollutant, including man made or artificial and natural, in the atmosphere. mashhad, as the biggest religious town in iran, has also been imposed with this problem. in this investigation the samples of rains during autumn 2002 and spring 2003 are analyzed. the results showed tha...

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