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...

the aim of the present study was to investigate the frequency and the type of discourse markers used in the argumentative and expository writings of iranian efl learners and the differences between these text features in the two essay genres. the study also aimed at examining the influence of the use of discourse markers on the participants’ writing quality. to this end the discourse markers us...

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...

the significance of the study of deixis was then mentioned. the purpose of the present study from the outset was to provide a comprehensive overview of all kinds of deixis in persian, describing and defining each in true while considering them structurally and semantically. chapter two consisted of two main parts. a review of the english studies in this respect, besides presenting persian liter...

even though, to date, a lot of studies have been conducted on the subject of politeness theory, there are very few studies regarding the applicability of this theory to translation between english and persian which shows the reason behind conducting the present study. this study was carried out with the aim of highlighting whether there is any difference between english and persian methods of u...

در این تحقیق، تنوع ژنتیکی جمعیت آرتمیا اورمیانا و آرتمیا فرانسیسکانا ی موجود در ایران با استفاده از 5 جفت آغازگر ریزماهواره ای (af-b105tail، af-a136، apdq03tail، apdq04tail و apdq05tail) ویژه ی آرتمیا فرانسیسکانا و آرتمیا پارتنوژنتیکا بررسی شد. از 50 سیست آرتمیا ی هر یک از این دو جمعیت به صورت انفرادی dna با روش گلوله ی داغ استخراج شد. با استفاده از آغازگر ها ی پنج گانه و از طریق واکنش زنجیره ا...

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...

the speech act of disagreement has been one of the speech acts that has received the least attention in the field of pragmatics. this study investigates the ways power relations, social distance, formality of the context, gender, and language proficiency (for efl learners) influence disagreement and politeness strategies. the participants of the study were 200 male and female native persian s...

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...

the purpose of this study was to investigate the impact of blended learning and multimedia softwares on iranian efl students vocabulary learning. in addition, the present study tried to examine the extent to which multimedia softwares can be applied into efl classes in iran. it also attempted to find out students attitudes toward using these softwares. to this end, 87 iranian efl learners at el...