in the present work, a simple and sensitive method was developed for determination of morphine and heroin using gold nanoparticles as resonance rayleigh scattering (rrs) and colorimetric technique’s probe. synthesized gold nanoparticles by sodium citrate reduction method have a negative charge layer on their surfaces because of self-assembled citrate anions on their surface. binding of morphin...

this study was carried out to investigate the effects of integrative vs. instrumental motivation, learning strategy use and gender on iranian efl learners. to this end, 120 efl learners both male and female majoring in english language and literature at shiraz university participated in the study. in order to conduct this study three instruments were used: oxford quick placement test, motivatio...

چکیده کنه تارتن دو لکه ای tetranychus urticae koch یکی از چندخوارترین آفات شناخته شده محصولات کشاورزی دنیا به حساب می آید. در این بررسی جمعیت تخم و مراحل فعال این کنه در شرایط آلودگی طبیعی و مصنوعی در برگ های 8 رقم لوبیا در سال 1392 در گلخانه و مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه ارومیه موردمطالعه قرار گرفت. آزمایش به صورت طرح کاملاً تصادفی برای شرایط مزرعه در10 تکرار و برای شرایط گلخانه ای...

in the area of vocabulary teaching and learning although much research has been done, only some of it has led to effective techniques of vocabulary teaching and many language learners still have problem learning vocabulary. the urge behind this study was to investigate three methods of teaching words. the first one was teaching words in context based on a traditional method of teaching that is,...

the ability of composing a coherent and extended piece of writing in second language is considered as a fundamental factor to convey information and ideas of learners through the academic issues. although learners may achieve a perfect academic writing skill through assigning the l2 tasks in content based instruction, but demonstration of their abilities may be related to their ability in l1 es...

according to coates’s (2004, as cited in zhang, 2010) definition of "conversational dominance" (p.111), it refers to the phenomenon of a speaker dominating others in interaction. specifically, it means how a speaker makes use of certain strategies to get the floor and maintain the floor. thus, the amount of talk is the main measurement for the dominance of the conversation. whether a speaker do...

previous studies have aimed at testing a hypothesis but the present study is data-first research in which researcher tries to form a theory from data rather than the use of data to test a hypothesis. this study aims at exploring teachers perceptions of the strengths and weaknesses of the current syllabus for college preparatory course. eight experienced teachers were selected to collect data du...

in this study, a simple, rapid and selective method was developed for the determination of dexamethasone. the proposed method is based on inhibitory effect of dexamethasone on the oxidation of orange-g by bromate in sulfuric acid media. the reaction was followed spectrophotometrically at 478.5 nm (?max). under optimum experimental conditions, (72.6 ?mol l-1 of orange-g, 0.76 mol l-1 of h2so4, 0...

abstract foreign and iranian cultures are far distinct in the constraints imposed on writing and translating for children, since the iranian literary system is mainly concerned with cultural and religious instructions which lead to manipulation of translated texts. this study sought to identify the cultural and social constraints and norms which determined the strategies applied in the transl...

teachers beliefs have usually been left unattended in the realm of educational research in iranian context. one of those beliefs which seems to impact teachers performance in the classroom is their sense of self-efficacy, which refers to teachers belief in their ability to enhance student achievement and in bringing about positive learning outcomes. the present study aimed to investigate the pr...