fluorescence chemical sensors for the highly sensitive and selective determination of pb2+ , hg2+, co2+ and fe3+ ions in aqueous solutions are described. the ion sensing system was prepared by incorporating lipophilic ligand (l) as a neutral ion-selective fluoroionophore in the plasticized pvc membrane containing sodium tetraphenylborate or potasium tetrakis (p-chlorophenyl) borate as a liphoph...

nowadays in trade and economic issues, prediction is proposed as the most important branch of science. existence of effective variables, caused various sectors of the economic and business executives to prefer having mechanisms which can be used in their decisions. in recent years, several advances have led to various challenges in the science of forecasting. economical managers in various fi...

in the past couple of decades sociocultural theory of sla and its implications in efl contexts have attracted attentions of research circles worldwide and aroused some controversies. firth and wagner (1997) have questioned the principles of the cognitive view which gives importance to mental constructs in favor of sociocultural view which highlights social and contextual constructs. but if soci...

abstract poor reading comprehension can result in failure in using references, benefiting from professional gatherings and resources, keeping up with the growing body of knowledge in the virtual world of the internet, and failing to achieve in efl programs. the purpose of the present quasi-experimental study was to explore the effects of background knowledge and previewing narrative and expos...

the present thesis is going to investigate the theme of despair, darkness and pesimism in philip larkins poetry. larkin is a british poet whose poems were composed in the dark and gloomy years of postwar. so, his poetry contains and reflects the same darkness and despair of his age. a good number of poems form different collections of his poetry are chosen and will be analyzed in the light of t...

abstract: in the paper of black and scholes (1973) a closed form solution for the price of a european option is derived . as extension to the black and scholes model with constant volatility, option pricing model with time varying volatility have been suggested within the frame work of generalized autoregressive conditional heteroskedasticity (garch) . these processes can explain a number of em...

the major aim of this study was to investigate the relationship between social and cultural capital and efl students’ critical thinking skills. this study takes this relationship in to account to see if people with different sociocultural status are different regarding their critical thinking skills. to this end, 160 university students majoring in english language and literature, english trans...

this study investigated the impact of explicit instruction of morphemic analysis and synthesis on the vocabulary development of the students. the participants were 90 junior high school students divided into two experimental groups and one control group. morphological awareness techniques (analysis/synthesis) and conventional techniques were used to teach vocabulary in the experimental groups a...

the concepts of similarity and dissimilarity have been the interest of many researchers. basically, in the studies the similarity between two objects or phenomena, has been discussed. in this thesis, we consider the case when the resemblance or similarity among three objects or phenomena of a set, 3-similarity in our terminology, is desired. later we will extend our definitions and propos...

adaptation of the lord of the rings is considered by many to be among the greatest, most successful and at the same time most popular of the above mentioned trend so far. it is my intention to look at the success and popularity of this epic fantasy in the light of the 9/11 attacks and the war on terror context of g. w. bush’s aura. in so doing i aim at bringing into the light the determining fa...