in this investigation the effect of external field on the electron density of nanostructures of cds, cdse, cdte, gaas and polymeric structure of three, four, five and six units of cds as a kind of nanosolar cells has been studied theoretically. as modeling this system in nanodimension, molecular structures has used. specific properties of molecular structures permit us to consider different sym...

abstract listening is a key and main tool in second language skill and its development is of prime concern to teachers and learners. furthermore, the application of technology in language classrooms has become more commonplace in the last fifty years. computer and the internet have made foreign language materials easy to access and use. so, the present study is an attempt to examine the effec...

according to webster and wind (1972) and anderson et al (1987), “organizational buying is a complex process and involves many people from different functional areas, multiple goals and potentially conflicting decision criteria. moreover, the customers of today are also more knowledgeable and selective when making their purchasing decisions. since a key to organizational survival is the retentio...

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 ...

the effect of the presence of perforations on he stresses of a plate is a problem which is of great interest in structural design and in the mathemattical theory of elasticity. among the many hole patterns that are likely to require consideration is the ring of equally spaced circular holes. the present worke investigates stress & strain analysis of a thin isotropic circular plate containing a ...

as polysemy is encountered frequently in english as foreign language. fl learners’ ability to disambiguate polysemous verbs becomes critical to their comprehension in the target language. this thesis, accordingly, investigated how iranian efl learners achieved comprehension of english polysemous verbs by using three different types of cues: (1) elaborated context, (2) semantic frames, and (...

the purpose of the research is to examine if integrating cooperative learning into vocabulary learning helps to increase word recognition of students in an elementary school in iran. it tries to investigate whether cooperative learning approach enables students to improve their language learning. this research used stad (students team achievement division) as a cooperative model in this study. ...

nowadays, the development of anti cancer drugs is an important subject in pharmacology. bisphosphonates (b.p) are a great choice for design and production of the types of drugs which not only could perform as anti cancer agents but also could inhibit the function of acetyl cholinesterase (ache). ache hydrolyzes the acetylcholine (which is a neurotransmitter in nervous system) using the oh in i...

abstract although music possesses some kind of power and using it has been welcome by many students in language classrooms, it seems that they take a non-serious image of the lesson while listening to songs and they may think that it is a matter of fun. the main objective of the present study was to investigate whether learning a foreign language through musical texts (songs) can have an impac...

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...