boron nitride semiconducting zigzag swcnt, $b_{cb}$$n_{cn}$$c_{1-cb-cn}$, as a potential candidate for making nanoelectronic devices was examined. in contrast to the previous dft calculations, wherein just one boron and nitrogen doping configuration have been considered, here for the average over all possible configurations, density of states (dos) was calculated in terms of boron and nitrogen ...

the present study aimed at exploring cognitions of iranian english teachers within the context of english for academic purposes (eap). to this end, the cognitions of two groups of eap teachers with respect to their pedagogical content knowledge (pck) and their sense of professional identity (pi) were probed. two language teachers and two content instructors who had at least five years of eap te...

any change in the refractive index of a laser active medium can lead to serious degradation of beam quality, laser beam modes, laser performance and variation in the intensity distribution. alteration in the refractive index of laser active medium is especially notable in high power lasers. it is clear that in the laser beam production, the pumping agent induces a great amount of heat which...

nitric oxide (no) is a small molecule synthesized by most of mammalian cells with diverse biological activities including vasodilatation, host defense and wound healing. impaired wound healing is a common occurrence among diabetics and patients receiving glucocorticoid therapy. on the other hand the application of laser in biomedical area have been increased. thus, the current studies were desi...

iv abstract this study examined the linguistic behaviors of two iranian efl teachers each of them teaching learners of two similar proficiency levels, a beginner level and an intermediate level, to investigate the relationship between the learners proficiency levels and the amounts and purposes for l1 use by the two teachers. the study was carried out to investigate whether there were differe...

abstract cooperative learning refers to small groups of learners working together as a team to solve a problem, complete a task, or accomplish a common goal. in a cooperative environment one’s success is directly related to the success of other members because the focus on the individual shifts towards the group. to test the effectiveness of the method, using jigsaw technique, a study was cond...

the purpose of the present study was to investigate the effect of task-based instruction of vocabulary on the receptive and oral productive acquisition of english vocabulary and compare the results with those obtained from the traditional method. the method and procedure applied in this study was as follows: after the implementation of opt, a group of sixty female students were chosen. the stu...

the present study sought to investigate the impact of using mind-mapping technique instruction on female elementary efl learners reading comprehension; it also investigated their attitudes towards using mind-mapping technique as a tool to improve their reading comprehension. this study followed a quasi-experimental design with two intact groups as experimental, and control groups. the participa...

current studies in second language (l2) learning have revealed the positive role of corrective feedback (cf) in both oral and written forms in different language features. the present study was an attempt to investigate the effect of both direct and indirect written corrective feedback (wcf) on the use of grammatical collocations in l2 writing. the study also sought to examine whether the effec...

abstract lexical knowledge of complex english words is an important part of language skills and crucial for fluent language use (nation, 2001). the present study, thus, was an attempt to assess the role of morphological decomposition awareness as a vocabulary learning strategy on learners’ productive and receptive recall and recognition of complex english words. so 90 sophomores (female and ma...