Objective: Metal concentrations in 53 soil samples of Shahr-e-Babak were determined.  Methods: Assessment of enrichment factor and geo-accumulation index revealed higher degree of contamination of Cd, Pb, and Cu in soil samples. Moreover, results of metal fractionation study revealed high amount of Cd and Pb are associated in weakly bounds may lead to environmental risk of these metals.  Result...

To recognize the dynamic of vegetation in eastern Iran as well as to ascertain interactions of human societies with theirenvironment, the present study is carried out on charcoal samples collected from Shahr-i Sokhta dated back to the Bronze Age.This research will present two different vegetal formations used by the inhabitants of Shahr-i Sokhta: riparian formationwith species such as tamarisk ...

abstract suitable seedling is one of the most important factors of onion growth and yield in transplanting method (tm). in order to investigation effects of different seedling size and age on marketable yield , biological yield, harvest index and some qualitative characters in onion an experiment was couducted at the agricultural research center of east azarbayjan in 2008. the factorial was con...

Objective: Metal concentrations in 53 soil samples of Shahr-e-Babak were determined.  Methods: Assessment of enrichment factor and geo-accumulation index revealed higher degree of contamination of Cd, Pb, and Cu in soil samples. Moreover, results of metal fractionation study revealed high amount of Cd and Pb are associated in weakly bounds may lead to environmental risk of these metals.  Result...

It has been recently discovered that the angular autocorrelation function of γ-ray bursts exhibits sharp peaks at angular separations of θ∼< 4 ◦ (Quashnock and Lamb 1993), and at θ ∼> 176 ◦ (Narayan and Piran 1993). These results were based on the publicly available BATSE catalogue. While an excess of very close pairs of bursts can naturally arise from burst repetition or from a spatial correla...

The gamma-ray burst (GRB) efficiency of converting kinetic energy into γ-rays is a very important quantity, which can potentially confirm or rule out the commonly accepted internal-shocks model. Several authors have been estimate the efficiency from the afterglow and GRB emission. Recently, some authors imply the efficiency derived from the latest observations from swift with this method is ver...

We use general arguments to show that a continuously powered radiative blast wave can behave self similarly if the energy injection and radiation mechanisms are self similar. In that case, the power-law indices of the blast wave evolution are set by only one of the two constituent physical mechanisms. If the luminosity of the energy source drops fast enough, the radiation mechanisms set the pow...