abstract the influence of cation?? and anion?? interactions on the strength and nature of n…h hydrogen bond has been investigated by quantum chemical calculations in s-triazine…3hf complex. ab initio calculations were performed at mp2/6-311++g(d,p) level of theory. the natural bond orbital (nbo) analysis and the bader’s quantum theory of atoms in molecules (aim) were also used to elucidate t...

abstract recent studies suggest that prelistening activities play an important role in the development of listening comprehension (e.g. long 1990;chiang and dunkel 1992; schmidt-rinehart 1994; jensen and hansen 1995; robinson et al., 1995; buck, 1995; foster and skehan,1996; teng 1996; robinson, 2001; chang and read 2006). in line with previous studies and to shed light on a new aspect of sche...

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 part one: the electrode oxidation potentials of a series of eighteen n-hydroxy compounds in aqueous solution were calculated based on a proper thermodynamic cycle. the dft method at the level of b3lyp-6-31g(d,p) was used to calculate the gas-phase free energy differences ,and the polarizable continuum model (pcm) was applied to describe the solvent and its interaction with n-hydroxy ...

this study compared the different effects of form-focused guided planning vs. meaning-focused guided planning on iranian pre-intermediate students’ task performance. the study lasted for three weeks and concentrated on eight english structures. forty five pre-intermediate iranian students were randomly assigned to three groups of guided planning focus-on-form group (gpfg), guided planning focus...

the present study investigated the effect of the two vocabulary teaching techniques in est, namely the use of translation and the use of visual aids as two separate vocabulary teaching techniques. to answer the question of the study, a pretest (michigan test) was administered to the 58 randomly selected est students at khajeh nasiredin tusi university, faculty of mechanics. after the homogeneit...

this study was conducted to investigate the impact of podcasts as a learning and teaching tool on iranian efl learners’ motivation for listening as well as on their listening comprehension ability. the study also investigated the learners’ perception towards listening to podcasts and examined whether the learners were likely to accept podcasts. out of fifty-five intermediate learners studying e...

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...

چکیده: در این تحقیق تأثیر ملاس که یکی از محصولات جانبی صنایع قند می باشد به عنوان یک افزودنی مقاومت خشک جدید در بهبود پالایش پذیری و ویژگی های فیزیکی و مکانیکی مقوای کنگره ای کهنه (occ) مورد بررسی قرار گرفته شد. بدین منظور پنج سطح ملاس( 0،5، 10، 15 و 18%) و سه سطح درجه روانی(420،400و320 میلی لیتر)به عنوان فاکتورهای متغیر در نظر گرفته شد و برای هر تیمار کاغذهای دست ساز با مساحت 2cm200 و وزن پای...

this study examined the effects of collaborative strategic reading and direct instruction in persuasion on iranian high school students persuasive writing and attitudes. students in three intact classes were assigned to one of three treatment conditions: collaborative strategic reading and direct instruction in persuasion or direct instruction in persuasion or a control group. treatment effects...