in this research we have studied the effect of some transition-metals (cu, ag and au) substitutions on two-electron reduction potential of flavins by application of dft method. all geometries have been optimized at blyp level of theory and “6-31+g** + lanl2dz” mixed basis set. the frequency job at the same method and basis sets has been performed to obtain gibbs free energy of compounds. it h...

in the present work, a simple and sensitive method was developed for determination of morphine and heroin using gold nanoparticles as resonance rayleigh scattering (rrs) and colorimetric technique’s probe. synthesized gold nanoparticles by sodium citrate reduction method have a negative charge layer on their surfaces because of self-assembled citrate anions on their surface. binding of morphin...

abstract according to increase in electricity consumption in one hand and power systemsreliability importance in another , fault location detection techniqueshave beenrecentlytaken to consideration. an algorithm based on collected data from both transmission line endsproposed in this thesis. in order to reducecapacitance effects of transmission line, distributed parametersof transmission line...

the following null hypothesis was proposed: h : there is no significant difference between the use of semantically or communicatively translates scientific texts. to test the null hypothesis, a number of procedures were taken first, two passages were selected form soyrcebooks of food and nutrition industry and gardening deciplines. each, in turn, was following by a number of comprehension quest...

deployable scissor type structures are composed of the so-called scissor-like elements (sles), which are connected to each other at an intermediate point through a pivotal connection and allow them to be folded into a compact bundle for storage or transport. several sles are connected to each other in order to form units with regular polygonal plan views. the sides and radii of the polygons are...

the present study was an attempt to compare the effect of peer metalinguistic corrective feedback on elementary and intermediate efl learners speaking ability to see which level benefits more from this type of feedback. to this end, 117 female efl learners at grade 3, al-zahra high school in kermanshah, iran were non-randomly chosen. the homogeneity of the participants was attained through a pi...

this research is a study on indicators of listening instruction in iranian english as a foreign language (efl) curriculum at guidance school and high school educational levels. this thesis aims at determining: a) the indicators of listening instruction at guidance school and high school efl curriculum. b) the indicators of listening instruction in irans guidance school and high school efl curri...

any change in the refractive index of a laser active medium can lead to serious degradation of beam quality, laser beam modes, laser performance and variation in the intensity distribution. alteration in the refractive index of laser active medium is especially notable in high power lasers. it is clear that in the laser beam production, the pumping agent induces a great amount of heat which...

foreign policy takes root from complicated matters. however, this issue may be more truth about armenia. although the new government of armenia is less than 20 years, people of this territory are the first ones who officially accepted christianity. in very past times, these people were a part of great emperors like iran, rome, and byzantium.armenia is regarded as a nation with a privileged hist...

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...