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...

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...

In this paper, after stating the characteristicof some of continuous distributions including, gamma, Crovelli’s gamma, Rayleigh, Weibull, Pareto, exponential and generalized gamma distribution with each other,these distributions were fit on drought data of Guilan state and the best distribution was presented. Then, severity and duration of the drought of different sites were investigated usi...

we describe here a suitable approach for the synthesis of n-unsubstituted monocyclic b-lactams under mild reaction conditions by the annelation of imines with substituted acetylchlorides. in this method the reaily available phtalimidoacetyl chloride were allowed to react with - dibenzylideneiminotoluene (hydrobenzamide) in the presence of an equimolar amount of triethylamine in refluxing toluen...

this study purported to compare and contrast the use of self-mention and evidentials as two mtadiscourse features in opinion columns of persian and english newspapers. the theoretical basis of this study is the idea that metadiscourse features vary across cultural boundaries. for this purpose, 150 persian and 150 english opinion columns were collected based on three factors of topic, audience a...

abstract this study aimed at investigating the impact of etymology strategy instruction on the development of vocabulary of iranian intermediate efl learners. etymology, knowledge of origin of words, roots, and affixes, has proved to be a controversial issue and a question of long debate with regard to its impact on the process of vocabulary learning. this study employed etymology strategy in ...

abstract this study aimed at investigating the translation of interjections from english into persian in dubbing. to carry out this study the expressive secondary interjections found in the film four weddings and a funeral and their equivalent in persian dubbed version were analyzed through the strategies proposed by cuenca. the descriptive analysis of the corpus showed that (strategy b) i.e...