attempts have been made to study the thermodynamic behavior of 1,3 butadiene purification columns with the aim of retrofitting those columns to more energy efficient separation schemes. 1,3 butadiene is purified in two columns in series through being separated from methyl acetylene and 1,2 butadiene in the first and second column respectively. comparisons have been made among different therm...

abstract the present study was conducted to examine the effect of proficiency on students interaction while carrying out the grammar-based task(s) in collaboration. in particular, the study examines whether the level of proficiency affects the learners’ focus of attention to grammatical and lexical features. the study takes a further step and examines whether there is any difference in the use...

abstract: mineral scaling in oil and gas production equipment is one of the most important problem that occurs while water injection and it has been recognized to be a major operational problem. the incompatibility between injected and formation waters may result in inorganic scale precipitation in the equipment and reservoir and then reduction of oil production rate and water injection rate. ...

this study investigated the functions, types and frequencies of code switching in the teachers and students discourse in elt classrooms. to this end, the participants of this study including two groups of teachers and students were selected. the first group of participants were two efl teachers teaching general english courses (at two different levels of proficiency) in an institutional program...

abstract deviation or in other words committing a crime is literally a social problem. this research that was conducted in 1389 and 1390 has tried to investigate the causes of crimes committed by young male inmates qazvin central prison and effective variables on their tendency to deviation. accordingly after collecting theoretical framework and offering theoretical model including both hirsch...

if the precise implementation of the principle of proportion and:balance between the violation and the penalty as well as the other dimensions could be considered as a stick yard for the imptementation of justice any lack of preciseness in carrying out such principle would not indeed be much too far from injustice . naturally ,if it would be imagined that the objective of balance between...

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...

the present research was an attempt to see how quranic lexical collocations were translated into english by two professional translators namely, abdullah yusuf(2005), and muhammad s. shakir(2012). the study attempted qualitatively to shed light on how translators dealt with quranic lexical collocations when transferring them to the target language based on the newmark(1988) model , and quantit...

this research was conducted in two protect and destroy region in the middle zagros, in illam province. in order to identification of ecological species group and evaluate density of regeneration, effect of many factors such as protection, vegetation, physiographic factors, physical and chemical properties of soil in study locations were studied. to achieve these purpose number of 54 plots using...

abstract: postmethod is a newly developed pedagogy which as an alternative to method rejects the notion of good or bad methods and the concept of best method that can be generalized and appropriate for all contexts. instead, it treats each context as unique and one of a kind which cant be compared with other cases. this study is a postmethod-oriented one which investigates whether and how far t...