in this project, 4,4?-methylenebis(3-chloro-2,6-diethyl trimellitimidobenzene) as a diacid, was prepared by the reaction of trimellitic anhydride (tma) with 4,4?-methylenebis(3-chloro-2,6-diethylaniline) (mcdea). the novel poly(amide-imide) (pai) was synthesized from the reaction of 4,4?-methylenebis(3-chloro-2,6-diethyl trimellitimidobenzene) as a diacid with mcdea under green condition using ...

abstract the primary purpose of this study was to explore the actual practices and cognitions of two groups of iranian eap teachers, i.e. language teachers and content teachers, with respect to teaching reading-comprehension and vocabulary. to this end, tehran university of medical sciences which authorizes both groups of teachers to teach eap courses was selected as the context of the study s...

fluorescence chemical sensors for the highly sensitive and selective determination of pb2+ , hg2+, co2+ and fe3+ ions in aqueous solutions are described. the ion sensing system was prepared by incorporating lipophilic ligand (l) as a neutral ion-selective fluoroionophore in the plasticized pvc membrane containing sodium tetraphenylborate or potasium tetrakis (p-chlorophenyl) borate as a liphoph...

abstract: the present study was undertaken to investigate whether 1) there is any significant correlation between iranian efl/eap learners’ l2 writing proficiency and their willingness to communicate, 2) there is any significant difference between efl and eap learners in terms of willingness to communicate, 3) there is any significant difference in wtc of iranian efl/eap learners with 1- nati...

abstract the present study was an attempt to investigate the effect of critical thinking on writing ability of 60 iranian intermediate efl learners studying at chenar language institute in khuzestan, iran. to this end, the participants of the study were selected based on their performance in an pet test, a cornell critical thinking test form x and a pre-test of writing. the participants un...

this study investigates the effect of teacher’s repetition as an input enhancement technique in explicit teaching of vocabulary items on efl learners’ later retrieval. to this end, 66 persian speaking english learners, aged 18 - 29, homogenized through a standard proficiency test (opt), were chosen and put into two experimental and control groups, each 33 learners. general service list (gsl), a...

the research questions were as follows: 1. is there any relationship between the students concious awareness of the form and implications of the conjuncations and their improvement in using appropriate conjunctions? 2. does students knowledge of the from and the implications of the conjunctions help them to produce more coherent writings. 3. does a comparison between english conjunctions and th...

as some definitions show, idioms are expressions whose meanings cannot be obtained from individual words. in every society, people use their own conceptions and feelings through different idioms and expressions. so every culture and society has their own idioms. some scholars proposed methods for translating idioms but baker’s strategies are very important and constructive. this research tried ...

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...

rivers and runoff have always been of interest to human beings. in order to make use of the proper water resources, human societies, industrial and agricultural centers, etc. have usually been established near rivers. as the time goes on, these societies developed, and therefore water resources were extracted more and more. consequently, conditions of water quality of the rivers experienced rap...