chapter one is devotod to collect some notion and background informations, which are needed in the next chapters. it also contains some important statements which will be proved in a more general context later in this thesis. in chapter two, we show that if the marginal factor-group is of order np1...pk,n>1, then we obtain a bound for the order of the verbal subgroup. also a bound for the bear-...

this study aimed at examining the effects of iranian efl learners’ anxiety, ambiguity tolerance, and gender on their preferences for corrective feedback (cf, henceforth). the effects were sought with regard to the necessity, frequency, and timing of cf, types of errors that need to be treated, types of cf, and choice of correctors. seventy-five iranian efl students, twenty-eight males and forty...

one of the applications of nanotechnology is use of carbon nanotubes for the targeted delivery of drug molecules. to demonstrate the physical and chemical properties of biomolecules and identify new material of drug properties, the interaction of carbon nanotubes (cnts) with biomolecules is a subject of many investigations. cnts is a synthetic compound with extraordinary mechanical, thermal, el...

abstract the following study, in the first place, attempted to examine the effect of less experienced teachers participation in experienced teachers classes on their own skills and teaching methodology, in the second place, attempted to find out the role of teachers training in students achievements. for this purpose, 21 efl teachers were selected according to available sampling in kish l...

deployable scissor type structures are composed of the so-called scissor-like elements (sles), which are connected to each other at an intermediate point through a pivotal connection and allow them to be folded into a compact bundle for storage or transport. several sles are connected to each other in order to form units with regular polygonal plan views. the sides and radii of the polygons are...

the central purpose of this study was to conduct a case study about the role of self monitoring in teacher’s use of motivational strategies. furthermore it focused on how these strategies affected students’ motivational behavior. although many studies have been done to investigate teachers’ motivational strategies use (cheng & d?rnyei, 2007; d?rnyei & csizer, 1998; green, 2001, guilloteaux & d?...

drought is transient phenomenon , slow , repetitive and integral part of the climate of each region. drought begins with a substantial reduction in precipitation over the long-term average rainfall and over time, reduced soil moisture and surface and ground water resources will continue to decrease. this phenomenon is the most important in bakhtegan basin because of its importance in strategic ...

Background and Objectives: The presence of industrial workshops has increased urban pollution. This study aimed to investigate the heavy metal pollutants of Yazd battery repairing workshops and to identify the ecological and environmental effects resulted. Materials and Methods: This descriptive cross-sectional study was carried out in Yazd. In this regard, the city was divided into three pa...

abstract recent studies suggest that prelistening activities play an important role in the development of listening comprehension (e.g. long 1990;chiang and dunkel 1992; schmidt-rinehart 1994; jensen and hansen 1995; robinson et al., 1995; buck, 1995; foster and skehan,1996; teng 1996; robinson, 2001; chang and read 2006). in line with previous studies and to shed light on a new aspect of sche...

let h be a separable hilbert space and let b be the set of bessel sequences in h. by using several interesting results in operator theory we study some topological properties of frames and riesz bases by constructing a banach space structure on b. the convergence of a sequence of elements in b is de_ned and we determine whether important properties of the sequence is preserved under the con...