in this study, a simple, rapid and selective method was developed for the determination of dexamethasone. the proposed method is based on inhibitory effect of dexamethasone on the oxidation of orange-g by bromate in sulfuric acid media. the reaction was followed spectrophotometrically at 478.5 nm (?max). under optimum experimental conditions, (72.6 ?mol l-1 of orange-g, 0.76 mol l-1 of h2so4, 0...

abstract this study set out to compare the effect of modality of presentation (subtitled vs. auditory) in the comprehension of verbal content of documentary films among iranian efl students. to this end, (30 male 30 female) students were chosen from two schools. after their homogeneity was established, the students attended the listening sessions to watch five documentary films over t...

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...

چکیده مورچه‏ها با حمایت از شپشک‏ها در مقابل دشمنان طبیعی، می‏توانند برنامه‏های کنترل بیولوژیک آن‏ها را مختل ‏نمایند. طی سال‏های 1389 و 1390 با نمونه‏برداری از باغات مرکبات شهرستان‏های ساری و بهشهر، فون و فراوانی نسبی مورچه‏هایِ همراه با شپشک‏ها مورد مطالعه قرار گرفت. همچنین، تاثیر تراکم‏های مختلف کاست کارگر گونه‏ی santschi lasius turcicus بر میزان تغذیه و فراسنجه‏های واکنش تابعی حشرات ماده و لا...

critical thinking ability has an important role in education. accordingly, scholars around the world are searching for new ways for teaching and improving students critical thinking ability. in line with the studies in efl contexts supporting the positive relationship between critical thinking and writing performances, this study investigated the differential effects of halverson’s critical thi...

126 abstract: in this research we studied the effects of cyclic hydration and dehydration of cysts of artemia urmiana and artemia parthenogenetica on the hatching percentage, survival and growth. the experiment was carried out in 3 treatments (1-3 hydration/dehydration cycles) with 3 replicates for each treatment. later effects of cold preservation at -20°c during three time periods were ...

one very decisive factor in students’ academic destiny is the result they get at final term examinations. because of its importance, both students and teachers are curiously anxious about them. as normally it is the case, these final term tests are prepared hurriedly in short time by teachers which result in students’ dissatisfaction, complaining on how the test was different from their expecta...

The interference of biological agents may cause behaviors such as interspecific predation, reducing their efficiencies. The interspecific predation of lacewing, Chrysoperla carnea (Steph.) and ladybeetle, Hippodamia variegata (Goeze) was investigated in the presence and absence of prey, Aphis gossypii Glover under laboratory conditions. In the presence and absence of prey, the larvae of lacew...