nowadays, air pollution is a global problem that has had significant growth by technology development, population growth andindustrial development. industrial development brought natural resources deterioration, more manufacturing products, and more environmental pollutants. if pollutant won’t be controlled, human-being and wildlife will face the critical risks. significant release and critical...

in this investigation the effect of external field on the electron density of nanostructures of cds, cdse, cdte, gaas and polymeric structure of three, four, five and six units of cds as a kind of nanosolar cells has been studied theoretically. as modeling this system in nanodimension, molecular structures has used. specific properties of molecular structures permit us to consider different sym...

this study investigated the effects of planning on second-language written production with regard to task type. the participants were 75 iranian learners of english as a foreign language attending a private foreign language institution. they were asked to complete two different types of writing tasks (expository writing task and argumentative writing task) in different planned conditions (indiv...

the purpose of this study was to examine the comparative effect of story retelling and role playing on efl learners’ vocabulary learning and reading comprehension. to carry out the purpose of the study 90 female learners of tabarestan language school located in noshahr were non-randomly selected. they took pet test and among these 90 participants 62 students were selected as homogenous learners...

the present study was conducted to investigate the effect of implicit focus on form through input flooding and the effect of noticing, explicit focus on form on linguistic accuracy. to fulfill the purpose of the study, 86 iranian pre-intermediate efl learners of one of the language institutes were chosen by means of administering ket as the homogeneity test. these learners were pretested throug...

this study compared the different effects of form-focused guided planning vs. meaning-focused guided planning on iranian pre-intermediate students’ task performance. the study lasted for three weeks and concentrated on eight english structures. forty five pre-intermediate iranian students were randomly assigned to three groups of guided planning focus-on-form group (gpfg), guided planning focus...

The Bāgh-e Fīrūzi area spreads over 130 ha and includes 10 known Achaemenid sites: seven with stone architectural elements, one with baked bricks on the surface, and two corresponding to 3 m-high rounded tepes. Tol-e Ājori is located on the eastern fringe of Bāgh-e Fīrūzi, on a border defined by Bāgh-e Fīrūzi located 300 m to the SE and Tol-e Jangī B located 400 m to the NW. This area was studi...

The Bāgh-e Fīrūzi area spreads over 130 ha and includes 10 known Achaemenid sites: seven with stone architectural elements, one with baked bricks on the surface, and two corresponding to 3 m-high rounded tepes. Tol-e Ājori is located on the eastern fringe of Bāgh-e Fīrūzi, on a border defined by Bāgh-e Fīrūzi located 300 m to the SE and Tol-e Jangī B located 400 m to the NW. This area was studi...

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...