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. ...

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...

phatic communion is a cultural concept which differs across cultures. according to hofstede (2001), the u.s. tends to have individualistic culture; however, asian countries tend to have collectivistic cultures. these cultures view phatic communion differently. in individualistic cultures like u.s., phatic communion reflects speakers’ socio-cultural relationships in conversations. to see whether...

abstract the present research is prepared to study the culture of tea consuming among iranian. the case group which was statistically used for this study was people of lahijan , about four hundred wich were chosen according to their age , gender , education and occupation , randomly selected to fill the questionnaire . then the data collected through the questionnaire was analyzed according ...

the purpose of this study was to investigate the effect of task repetition on accuracy of iranian efl learners ’speaking ability. in order to achieve this purpose, a null hypothesis was developed: there is no statistically significant difference between accuracy speaking ability in iranian efl learners by use of task repetition. ; of course i should mention that, beside this null hypothesis, an...

previous studies regarding teachers’ beliefs have revealed that teachers’ beliefs have influence on their classroom practices. the current study aimed to investigate the effect of teachers’ beliefs about teaching reading strategies on students’ motivation and success in reading comprehension in the context of english teaching as a foreign language in high schools of mazandaran, iran. data were ...

abstract this study is an attempt to determine the effect of nano- technology education on science lesson for fifth grade in primary school in the city of kermanshah. this research is experimental and is conducted in the from of pre-test and post- test for the control group. an achievement test was administered to determine the rate of learning in the students. the research is an applied one. ...

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...

the subjects of the study are only the tefl teachers and students at gilan university. to obtain the desired data, a questionnaire which was based on the theories and disecussions gathered, was used as the main data gathering instrument. to determine the degree of relationship between variables, covariance and pearson product moment correlation coefficient were the formulas applied. the data we...

the methods which are used to analyze microstrip antennas, are divited into three categories: empirical methods, semi-empirical methods and full-wave analysis. empirical and semi-empirical methods are generally based on some fundamental simplifying assumptions about quality of surface current distribution and substrate thickness. thses simplificatioms cause low accuracy in field evaluation. ful...