in this thesis, first the notion of weak mutual associativity (w.m.a.) and the necessary and sufficient condition for a $(l,gamma)$-associated hypersemigroup $(h, ast)$ derived from some family of $lesssim$-preordered semigroups to be a hypergroup, are given. second, by proving the fact that the concrete categories, semihypergroups and hypergroups have not free objects we will introduce t...

abstract in first part of this project, the use of a new and biguanid-like catalyst supported on silica as a recyclable catalyst provides a new route for the synthesis of a variety of arylalkylidene rhodanine derivatives through knoevenagle reaction in at present of solvent at room temperature. rhodanine derivatives and especially arylalkylidene rhodanines have proven to be attractive compound...

the aim of the present study was to investigate the frequency and the type of discourse markers used in the argumentative and expository writings of iranian efl learners and the differences between these text features in the two essay genres. the study also aimed at examining the influence of the use of discourse markers on the participants’ writing quality. to this end the discourse markers us...

throughout this dissertation r is a commutative ring with identity and m is a unitary r-module. in this dissertation we investigate submodules of multiplication , prufer and dedekind modules. we also stat the equivalent conditions for which is ring , wher l is a submodule of afaithful multiplication prufer module. we introduce the concept of integrally closed modules and show that faithful mu...

the space now known as complete erdos space ec was introduced by paul erdos in 1940 as the closed subspace of the hilbert space ?2 consisting of all vectors such that every coordinate is in the convergent sequence {0} ? { 1 n : n ? n}. in a solution to a problem posed by lex g. oversteegen we present simple and useful topological characterizations of ec. as an application we determine the ...

the purpose of this study was to investigate iranian efl learners’ beliefs about the role of rote learning (rl) in vocabulary learning strategies; besides, the study examined if english proficiency would influence learners’ vocabulary learning strategy use. this study addresses the need for a clear understanding of the role of rl in efl vocabulary learning by looking at iranian efl learners’ ow...

in this thesis, barium ferrite nano particles were prepared by sol-gel method. their structural and magnetic properties of samples have been investigated using thermo gravimetric analysis (tg-dta), x-ray powder diffractometer (xrd), fourier transform infrared (ftir), scanning electron microscopy (sem), field emission scanning electron microscopy (fesem), ac susceptometer, vibrating sample magne...

the importance of writing as a complex skill in applied linguistics has drawn the attention of many researchers to evaluate textbooks in order to help learners gain self-sufficiency and autonomy in the field of language use and communication. investigations have shown that developments in textbooks evaluation can promote the quality of pedagogies and consequently the learning. this study attemp...

the purpose of this study is to investigate the relationships between teachers’ immediacy behaviors and iranian students’ willingness to talk in english classes. analysis of the results from willingness to talk scale represents a relatively high level of willingness to talk in english classrooms among iranian language learners. the total mean score of students’ willingness to talk was 66.3 ou...

the present study sought to examine whether a task-based approach could have an impact on raising awareness of collocations. moreover, it sought to investigate the facilitative role of consciousness-raising tasks of collocations in the communicative instances of use. to this end, 68 intermediate learners of english were selected via a placement test. the participants were taught with classroom ...