Background and Objectives: Perchlorate, as an emerging contaminant, has attracted notice of the most individuals and organizations. Presence of perchlorate in the human body can lead to inappropriate regulation of metabolism in adults. Moreover, due to inhibition of iodide uptake in the thyroid gland, it causes neurological and behavioral problems in infants and children. United States Environm...

in this thesis, barium ferrite nano particles were prepared by sol-gel method. their structural and magnetic properties of samples have been investigated using thermo gravimetric analysis (tg-dta), x-ray powder diffractometer (xrd), fourier transform infrared (ftir), scanning electron microscopy (sem), field emission scanning electron microscopy (fesem), ac susceptometer, vibrating sample magne...

Background and objectives: Mountain habitats, due to their climatic conditions, are considered to be very sensitive areas and generally have less plant diversity compared to the lower elevations. Unfortunately, in the past years, due to human attacks, parts of these areas have been destroyed and now some areas are either devoid of vegetation or have very little vegetation. Since Crataegus and B...

This study was conducted to evaluate the effects of Atriplex canescens on soil properties and organisms' activities under grazing and exclosure conditions at Shahriar rangelands. In each site, four transects were selected by random-systematic method and 10 quadrates of nine m2 were established along transects with 30-m intervals. In each quadrate, the amount of seed per plant, litter and the nu...

Archaeological sites in desert areas are at risk for destroying and reburied with sand dunes by sand storms. One of the most important issues for archaeologist and conservators in these regions are maintenance of archaeological remains, during the excavation process and after it, There are several sand dune stabilization methods such as mechanical dune stabilization, mulch or protective screen,...

  Tree uprooting creates multiple microsites that can be effective on soil heterogeneity. In order to investigate the soil features in pit and mound location, twenty hectare areas of Tarbiat Modares University Experimental Forest Station studied that is located in Mazandaran province, in the north of Iran. Numbers of thirty four uprooted trees were found in study areas. Five microsites were con...

cement is an essential ingredient in the concrete buildings. for production of cement considerable amount of fossil fuel and electrical energy is consumed. on the other hand for generating one tone of portland cement, nearly one ton of carbon dioxide is released. it shows that 7 percent of the total released carbon dioxide in the world relates to the cement industry. considering ecological issu...