in this thesis, a new optically active poly(amide-imide) (pai) was synthesized by the indirect polycondensation reaction of the l-phenylalanine based diacid chloride and 4,4?-diaminodiphenylether in the presence of triethylamine in n-methyl-2-pyrrolidone. the formation of pai was confirmed by ftir, 1h nmr and elemental analysis. in next step, the surface of titanium dioxide (tio2) nanoparticles...

چکیده: پژوهش حاضر به بررسی تطبیقی اعتماد اجتماعی در بین دبیران زن و مرد مقطع راهنمایی شهر ایلام می پردازد. امروزه در جوامع شاهد گسترش ارتباطات هستیم و با توجه به این که دامنه کنش های اجتماعی از حد روابط با آشنایان و دوستان فراتر رفته و به تعامل با کنشگران غربیه و نا آشنا گسترش یافته است، لزوم وجود اعتماد، بیش از پیش احساس می شود. اما با توجه به نقش دبیران در نهادهای آموزشی، در انتقال ارزش ها و...

abstract this study aimed at investigating the effect of bilingual teaching of cognate words (persian-english) on iranian upper intermediate efl learners’ knowledge of lexical development. for this purpose,100 subjects participated in this study out of which 40 learners were selected for this study and they were assigned into two groups, control and experimental. cross-language cognates (wor...

چکیده معضل چاقی به عنوان عارضه ای جدی برای زندگی بی تحرک و ماشینی، مورد توجه اغلب مراکز بهداشتی و درمانی دنیا قرار گرفته است. چاقی عامل زمینه ساز و در واقع عامل خطری برای بروز بیماری های قلبی - عروقی است که عموماً با کاهش طول عمر مورد انتظار و افزایش بیماری همراه است. هدف پژوهش حاضر تأثیر 12 هفته تمرینات ویبریشن کل بدن، تمرینات هوازی و تمرینات ترکیبی( هوازی و ویبریشن کل بدن) بر ترکیب بدنی زنان ...

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...

abstract previous studies on willingness to communicate (wtc) have shown the influence of many individual or situational factors on students’ tendency to engage in classroom communication, in which wtc has been viewed either at the trait-level or situational level. however, due to the complexity of the notion of willingness to communicate, the present study suggests that these two strands are ...

abstract sensitive and precise voltammetric methods for the determination of trace amounts of furaldehydes, mainly as furfural (f) and 5-hydroxymethyl-2-furaldehyde (hmf), in waste waters and other matrices is described. determination of total furaldehyde at < ?g g-1 levels in alkaline buffered aqueous media was individually investigated. by the use of ordinary swv and adsorptive square wave ...

the present study set out (a) to examine the categories of pedagogical knowledge related to the act of teaching of novice and experienced teachers as gleaned from their verbal report of what they were thinking about while teaching and (b) to compare the categories of pedagogical knowledge of novice and experienced teachers. the aim of comparing these two groups of teachers was to see whether di...

the current study examined iranian undergraduate efl students’ willingness to communicate with regard to their vocabulary knowledge. in general, participants were somewhat willing to communicate in english. the total mean score of 730 university students’ perception of willing to communicate was 83.53 out of 135. results, regarding four parts of willingness to communicate, revealed that part...

introruction khawf in(iran)-herat and mazaresharif and shirkhan bandar in (afghanistan)-dushanbe in (tajikistan)_(kirgizstan)-kashghar in(china) project railway network is under construction that it is as a significant corridor for revitalizing silk road corridor in the region .at the present there are three different gauge in the region central asia with 1,520 mm gauge and turkey-islamic repu...