Background: Unsustainable development of human societies, especially in arid and semi-arid areas, is one of the most important environmental hazards that require preservation of groundwater resources, and permanent study of qualitative and quantitative changes through sampling. Accordingly, this research attempts to assess and analyze the spatial variation of quantitative and qualitative indica...

Altogether 20 groundwater samples were collected around the Lakan Pb and Zn mine in Iran. Samples were analyzed for 8 constituents including Fe, Pb, Hg, Mn, Zn, CN, SO4 and Cl using standard method. The results show that the average concentrations of constituents were 0.01, 0.60, 0.10, 0.01, 0.40, 35, 0.01 and 5.95 mg/kg for Fe, Mn, Pb, Zn, Hg, SO4, CN and Cl, respectively. The computed contami...

The question of who is and who is not a bilingual is more difficult to answer than it first appears. Bilingualism was long regarded as the equal mastery of two languages, a definition that still prevails in certain glossaries of linguistics. However, today's complex world requires a more exact definition and analysis of the competencies that community members require to interact with speakers o...