On the atomic scale, Molecular Dynamic (MD) Simulation of Nano Al cluster impact on Al (100) substrate surface has been carried out for energies of 1-20 eV/atom to understand quantitatively the interaction mechanisms between the cluster atoms and the substrate atoms. The many body Embedded Atom Method (EAM) was used in this simulation. We investigated the maximum substrate temperature Tmax  and...

We present a summary of strange particle yields measured by the experiment NA49 in central Pb+Pb collisions in the beam energy range 20 158 AGeV. The comparison with thermal hadron model results shows that above 30 AGeV, a strangeness undersaturation parameter γS must be employed to describe the data. This suggests a change in the strangeness production mechanism at this energy. We find that th...

Single-stranded junctions/loops are frequently occurring structural motifs in nucleic acid structures. Due to the polyanionic nature of the nucleic acid backbone, metal ions play a crucial role in the loop stability. Here we use the tightly bound ion theory, which can account for the possible ion correlation and ensemble (fluctuation) effects, to predict the ion-dependence of loop and stem-loop...

Within the framework of an isospin-dependent Boltzmann-Uehling-Uhlenbeck (BUU) model using initial proton and neutron densities calculated from the nonlinear relativistic mean-field (RMF) theory, we compare the strength of transverse collective flow in reactions Ca + Fe and Cr + Ni, which have the same mass number but different neutron/proton ratios. The neutron-rich system (Ca+Fe) is found to ...

Background:  In this study a series of basic dosimetric properties of a low-density (LD) gel dosimeter are investigated. The dose response is studied regarding to linearity, sensitivity, dose-rate and energy dependence as well as lung tissue equivalence. Materials and Methods: The LD gel was made by mixing the polymer gel with expanded polystyrene spheres. Energy dependence was studied...

classical trajectory (monte carlo) calculation is used to calculate collision rate constants of ion-quadrupolar molecule interactions for the h¯+c2h2 system. the method presented here takes into account the effect of the induced dipole-induced dipole potential on ion-quadrupolar molecule collision rate constants. it is also assumed that the colliding particles have a definite size. the thermal ...

this study took an epidemiological approach toward the problem of drug addiction in tehran. the subjects were 300 addicts chosen on the basis of stratified random selection out of the population of 3627 prisoners who were all proven addicts and sentenced to imprisonment by the court in the year 1370. a descriptive survey showed that drug addiction generally, and heroin addiction specifically, i...