in this work, a novel and fast method for direct analysis of volatile compounds (davc) of medicinal plants has been developed by holding a filament from different parts of a plant in the gc injection port. the extraction and analysis of volatile components of a small amount of plant were carried out in one-step without any sample preparation. after optimization of temperature, extraction time a...

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 ...

although there are studies on pragmatic assessment, to date, literature has been almost silent about native and non-native english raters’ criteria for the assessment of efl learners’ pragmatic performance. focusing on this topic, this study pursued four purposes. the first one was to find criteria for rating the speech acts of apology and refusal in l2 by native and non-native english teachers...

چکیده : تحقیق حاضر به منظور مقایسه دو روش تدریس انتزاعی و تدریس در متن بر یادگیری دستور زبان ایتالیاییِ زبان آموزان ترم 1 مدرسه ایتالیایی تهران در تابستان 89 صورت گرفت. روش تحقیق آزمایشی بوده و پژوهش بر 30 نفر از زبان آموزان مدرسه ایتالیایی تهران که بصورت تصادفی به 2 گروه جایگزین شدند صورت گرفت. ابزار تحقیق آزمون 30 سوالی تستی از بانک سوالات استاندارد شده بود که به تصادف انتخاب شده بودند.روشهای...

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 ...

بررسی تنوع ژنتیکی ژنوتیپ‏های بومی پیاز ایرانی در مقایسه با انواع خارجی چکیده: برنامه های اصلاحی گیاهان بر اساس تنوع و انتخاب صفات برتر کمی و کیفی صورت می گیرد. لذا، ارزیابی تنوع ژنتیکی، اولین مرحله در برنامه های اصلاحی است. در این راستا، استفاده از روش های جدید مطالعه‏ی تنوع ژنتیکی ضروری به نظر می رسد. در این بررسی تعیین تنوع ژنتیکی سیزده ژنوتیپ پیاز ایرانی در مقایسه با دو ژنوتیپ خارجی با است...

this study was an attempt to investigate and compare the effect of lexical inferencing and concept mapping on developing vocabulary retention of iranian language learners. sixty homogeneous students from different intact classes who were being taught as intermediate learners in sokhan english institute participated in this study. they were in different classes. a teacher made test as a pre-test...

there is less published research about how teachers in efl contexts respond to students who are relatively less mature and less competent l2 writers. while writing researchers have examined various issues concerning peer and teacher response in writing-oriented classes, little research has centered on the effect of collaborative tasks particularly dictogloss on writing skills. output collaborat...