heteropoly acids (hpa) and their salts have advantages as catalysts which make them both economically and environmentally attractive, strong br?nsted acidity, exhibiting fast reversible multi-electron redox transformations under rather mild conditions, very high solubility in polar solvents, fairly high thermal stability in the solid states, and efficient oxidizing ability, so that they are imp...

within the components of communicative competence, a special emphasis is put on the “rules of politeness,” specifically the politeness strategies (brown and levinson, 1978) that speakers deploy when performing the request speech act. this is because the degree of imposition that making a request places upon one’s interlocutor(s) has been seen to be influenced by several factors among which, as ...

1.1 introduction “i see translation as the attempt to produce a text so transparent that it does not seem to be translated. a good translation is like a pane of glass. you only notice that it’s there when there are little imperfections- scratches, bubbles. ideally, there shouldn’t be any. it should never call attention to itself.” “norman shapiro” (venuti, 1995:1) edward fitzgerald is the br...

abstract: the present study is about prophet ishmael, some parts of his life; his personality in the quran and the bible; and the comparison of the content of these two religious books. compilation of the study has been done with a new perspective and new presentation approach. since prophets have been human beings’ role model and their life has been a perfect example for humanity in all ages,...

abstract : the purpose of this research is to study a bout multiple manifestations of poem music in hakim sanaee ghaznavi poems yherefore the first seetion of this book study and describes the complete works of this research about poem music love poem sanaee poem and this known and famous poets life and works the second section explained the external music of sanaee poems that for better u...

cement is an essential ingredient in the concrete buildings. for production of cement considerable amount of fossil fuel and electrical energy is consumed. on the other hand for generating one tone of portland cement, nearly one ton of carbon dioxide is released. it shows that 7 percent of the total released carbon dioxide in the world relates to the cement industry. considering ecological issu...

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...

flow in natural river bends is a complex and turbulent phenomenon which affects the scour and sedimentations and causes an irregular bed topography on the bed. for the reason, the flow hydralics and the parameters which affect the flow to be studied and understand. in this study the effect of bed and wall roughness using the software fluent discussed in a sharp 90-degree flume bend with 40.3cm ...