abstract in aggregate, active forms of reactive silica with mineral names are sometimes associated with sand and gravel in concrete mixture. alkali hydroxides originated from alkalis in the cement or other resources form an alkaline silica gel with this reactive silica which becomes swallowed and expanded during time causing damage to concrete. there have been growing researches on alkaline r...

the neogene intrusion masses in the noudeh-enghelab area located to the north of sabzevar ophiolite have cut the late cretaceous ophiolitic rocks, sedimentary- volcanic and eocene volcanic rocks and have been covered by pliocene and quaternary deposits. the margin is of lava with basalt, phyric andesite-basalt and andesite and the central parts (dome shaped) composed of phyric andesite-trachyan...

the present dissertation aims to investigate four-word lexical bundles in applied linguistics research articles by iranian and internationally-published writers. the aims of this study are two-fold: first of all, attempts have been made to create a comprehensive list of the most commonly used four-word lexical bundles categorized by their type and token frequency, their structural characteristi...

among the low–dimensional allotropes of carbon, nanotubes and graphene have attracted very much attention from nano–science and nanotechnology specialists. they have been proposed as building blocks in nanometer device engineering. however, these structures are not defect–free. in this thesis, we focused on defective carbon nanotubes and graphene, and studied the effect of couple of very common...

a large number of single research studies on the effects of strategy-based instruction (sbi) in teaching english as a foreign or second language has been conducted so far. however, the lack of a comprehensive meta-analysis targeting the effectiveness of english language sbi is observed. moreover, the findings of experimental studies regarding the context of the english language, proficiency lev...

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...

this study explored reading strategy use of tefl ma students when they read academic research articles in english. the purpose of this study was to investigate how this group of readers typically approaches reading academic research articles related to their field of study, and also what they do in reading such research articles. the aim of the present study was bilateral. first, the researcher...

abstract previous studies on willingness to communicate (wtc) have shown the influence of many individual or situational factors on students’ tendency to engage in classroom communication, in which wtc has been viewed either at the trait-level or situational level. however, due to the complexity of the notion of willingness to communicate, the present study suggests that these two strands are ...

previous studies have aimed at testing a hypothesis but the present study is data-first research in which researcher tries to form a theory from data rather than the use of data to test a hypothesis. this study aims at exploring teachers perceptions of the strengths and weaknesses of the current syllabus for college preparatory course. eight experienced teachers were selected to collect data du...

even though, to date, a lot of studies have been conducted on the subject of politeness theory, there are very few studies regarding the applicability of this theory to translation between english and persian which shows the reason behind conducting the present study. this study was carried out with the aim of highlighting whether there is any difference between english and persian methods of u...