Sulfur dioxide has two important sources in the atmosphere and this is why most of scientists believe in a geographic split in the globe. Power plants, major emitter of SO2, are located in north hemisphere such as in Russia, China, Canada and the USA. In south hemisphere, phytoplankton produces a massive amount of dimethyl sulfide (DMS) and dimethyl disulfide (DMDS). Then these types of reduced...

Background & Aims: Occupational accidents are known as one of the most important causes of disabilities and mortality in developed and developing countries. Construction industry is one of the most high risk occupations which its hazardous are not known completely. In addition to occupational accidents, construction workers are faced many diseases factors such as asbestos, silicon, fumes and no...

hydrologists have always tried to classify atmospheric and hydrologic events in order to simplify the hydrologic convolutions and the observations or to save the time and the budget. most of these methods are used for the regionalization of hydrologic phenomena like rainfall,streamflow and other components of water cycle.multivariate techniques have been underlined as suitableand powerful tools...