asymmetric membranes are widely used in many industrial membrane separation processes. the major advantage of membrane filtration over the conventional process is its ability to remove a wider spectrum of particles without using any chemicals. hollow fiber configuration offer many advantages over flat-sheet or tubular membranes. the spinning process of hollow fiber may look simple, yet it is te...

nitric oxide (no) is a small molecule synthesized by most of mammalian cells with diverse biological activities including vasodilatation, host defense and wound healing. impaired wound healing is a common occurrence among diabetics and patients receiving glucocorticoid therapy. on the other hand the application of laser in biomedical area have been increased. thus, the current studies were desi...

recent studies in scientific education as well as foreign and second language instruction suggest that thinking has rarely been an integral part of education and training in classroom. some scholars decried the lack of emphasis on thinking in the institutes and schools. they noted that memorization and drills were rewarded,while inquiry, reflection, and consideration of alternatives were frowne...

this study attempts to investigate the effect of peers’ revision in comparison to that of the teacher, and whether peers’ comments and teachers’ comments facilitate students’ revision? if yes, which one is more effective? also attempts have been made to see which aspects of language are more highlighted by peers versus teachers when commenting. besides, it is investigating the student’s attitud...

this study compared the different effects of form-focused guided planning vs. meaning-focused guided planning on iranian pre-intermediate students’ task performance. the study lasted for three weeks and concentrated on eight english structures. forty five pre-intermediate iranian students were randomly assigned to three groups of guided planning focus-on-form group (gpfg), guided planning focus...

asymmetric polyethersulfone (pes) microfiltration flat sheet membranes were composed by the phase inversion method (pim) and were used as supports. composite membranes were fabricated by coating silicone rubber as selective layer. effect of different concentrations of pes and pdms and different solvent such as nmp, dmf and dms effects as pes solvents and support thickness and different coagulat...

abstract tasks nowadays are at the center of attention in sla research. task types is one of the critical issues in this regard, their effectiveness and suitability to any particular context, their characteristics and the result they yield are among some of these issues. on the other hand, discourse markers (dms) have been very much investigated and their effectiveness in conveying the meaning...

the thesis has been arranged into five chapters and mainly concerned with the baer-invariant of groups which is the generalization of the schur-multiplier with respect to the variety of groups. chapter one is devoted to collect some notation and background information which are needed in the next chapters. its also contains some important statements which will be generalized in this thesis. cha...

since the 1960s the age effects on learning both first and second language have been explored by many linguists and applied linguists (e.g lennerberg, 1967; schachter, 1996; long, 1990) and the existence of critical period for language acquisition was found to be a common ground of all these studies. in spite of some common findings, some issues about the impacts of age on acquiring a second or...

this study aimed to investigate the effects of listening strategy training on iranian efl learners listening comprehension and use of such strategies. this work, employing an experimental methodology, was conducted among 60 adult efl learners from a language institute in isfahan, iran, as participants. the participants, who were selected based on the results of a placement test, were assigned t...