The present study investigates the effect of e-mail on Iranian learners of English and focuses on teaching thewriting skillvia e-mail. More specifically, the study investigates (a) whether using e-mail has any statistically significant effect on improving high school students' writing skill, and (b) whether the proficiency level has any relation with students’ writing improvement through using ...

We consider a four component gas undergoing a bimolecular chemical reaction of type A1 + A2 A3 + A4, described by the Boltzmann equation (BE) for chemically reactive mixtures. We adopt hard-spheres elastic cross sections and modified line-of-centers reactive cross sections depending on both the activation energy and geometry of the reactive collisions. Then we consider the hydrodynamic limit sp...