In this work, SiO2 –ZrO2 mixed oxides was prepared by the polymeric sol–gel route. The characterization of pore structure, which determines the permeation process of membrane, is of great importance. So far, most investigations have focused on such pore structure as specific surface area and pore size distribution, but the surface fractal, the important parameter reflecting the roughness of por...

landscape metrics quantifies structural features of the landscape. one of the advantages of these metrics is a possibility to use them in fast cumulative assessment of the development activities in the environment. in this paper, the cumulative effects of road network expansion on the tree cover of gorgan, kordkuy, aliabad townships in golestan province were investigated. to prepare the require...