all analytical methods are generally based on the measurement of a parameter or parameters which are somehow related to the concentration of the species.an ideal analytical method is one in which the concentration of a species can be measured to a high degree precision and accuracy and with a high sensitivity. unfortunately finding such a method is very difficult or sometimes even impossible.in...

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...

a one dimensional dynamic model for a riser reactor in a fluidized bed catalytic cracking unit (fccu) for gasoil feed has been developed in two distinct conditions, one for industrial fccu and another for fccu using various frequencies of microwave energy spaced at the height of the riser reactor (fccu-mw). in addition, in order to increase the accuracy of component and bulk diffusion, instanta...

writing as a productive skill requires practice in the basic sub-skills of vocabulary and grammar. in fact, grammar has been viewed as the core of programs in writing classes to help the students put the elements of sentence together and combine sentences of specific lengths to come up with an error-free work of art. conceptualizing l2 writing in this way introduces writing as a product and enc...

assigning premium to the insurance contract in iran mostly has based on some old rules have been authorized by government, in such a situation predicting premium by analyzing database and it’s characteristics will be definitely such a big mistake. therefore the most beneficial information one can gathered from these data is the amount of loss happens during one contract to predicting insurance ...

the primary goal of the current project was to examine the effect of three different treatments, namely, models with explicit instruction, models with implicit instruction, and models alone on differences between the three groups of subjects in the use of the elements of argument structures in terms of toulmins (2003) model (i.e., claim, data, counterargument claim, counterargument data, rebutt...

the purpose of this study was to examine the english language needs of medical students at tehran university of medical sciences . analysis of the needs took place for three groups: 320 undergraduate students, 30 postgraduate students and 20 university instructors. a triangulation approach to collect data was used in which a combination of the quantitative (using the questionnaires) and qualita...

this thesis attempts to study the representations of the third-world intellectuals in three fictional works by the british-educated trinidadian nobel-winner v. s. naipaul: the mimic men, a bend in the river, and magic seeds. the first one recounts the story of ralph singh’s sense of alienation, his experiences as a colonial politician, and his struggle to give order to his disorderly world thro...

data envelopment analysis (dea) is a powerful tool for measuring relative efficiency of organizational units referred to as decision making units (dmus). in most cases dmus have network structures with internal linking activities. traditional dea models, however, consider dmus as black boxes with no regard to their linking activities and therefore do not provide decision makers with the reasons...

abstract this study evaluates the iranian pre-university english textbook in terms of needs, objectives, content, and methodology. the study was designed on the qualitative- quantitative survey basis using interviews and questionnaires, a researcher-made textbook evaluation checklist and a needs analysis questionnaire. the textbook evaluation questionnaire was used in this study to elicit the ...