among the low–dimensional allotropes of carbon, nanotubes and graphene have attracted very much attention from nano–science and nanotechnology specialists. they have been proposed as building blocks in nanometer device engineering. however, these structures are not defect–free. in this thesis, we focused on defective carbon nanotubes and graphene, and studied the effect of couple of very common...

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...

introduction acetic acid bacteria are large group of obligate aerobic gram negative bacteria with the ability to oxidize ethanol to acetic acid (1). they are widely distributed in natural habitats and classified in family acetobacteraceae. members of this family are useful in industrial production of vinegar(2). acetic acid bacteria (aab) can use substrates as glucose, ethanol, lactate or glyc...

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...

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...

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 ...

the purpose of this quantitative study was to investigate the relation between efl teachers’ self-efficacy beliefs and their success. moreover, the study was an analysis of the teacher age, gender and years of teaching experience, to examine the manner in which these factors relate to teacher self-efficacy as defined by bandura (1997) and teaching effectiveness as evaluated by their own student...

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...

the rationale behind the present study is that particular learning strategies produce more effective results when applied together. the present study tried to investigate the efficiency of the semantic-context strategy alone with a technique called, keyword method. to clarify the point, the current study seeked to find answer to the following question: are the keyword and semantic-context metho...

apart from other aspects, desert is a natural environment and is one of the appealing terrestrial elements. putting its symbolic and fictional senses aside, the term “desert” bears mystic sense more than material sense. in addition to the worlds materialistic experiences, desert has attracted the attention of writers because it creates a kind of inner experience, which returns the individual in...