in this thesis, a new optically active poly(amide-imide) (pai) was synthesized by the indirect polycondensation reaction of the l-phenylalanine based diacid chloride and 4,4?-diaminodiphenylether in the presence of triethylamine in n-methyl-2-pyrrolidone. the formation of pai was confirmed by ftir, 1h nmr and elemental analysis. in next step, the surface of titanium dioxide (tio2) nanoparticles...

abstract: country’s fiber optic network, as one of the most important communication infrastructures, is of high importance; therefore, ensuring security of the network and its data is essential. no remarkable research has been done on assessing security of the country’s fiber optic network. besides, according to an official statistics released by ertebatat zirsakht company, unwanted disconnec...

in one pole of the continuum of language learning, theoreticians and practitioners traditionally consider english as english as a second language or english as a foreign language. however, in the other pole of this continuum where english is thought of as the most effective tool for international communication, it is referred to as a lingua franca. those who favor an approach to english growing...

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...

nitric oxide (no) is a small molecule synthesized by most of mammalian cells with diverse biological activities including vasodilatation, host defense and wound healing. impaired wound healing is a common occurrence among diabetics and patients receiving glucocorticoid therapy. on the other hand the application of laser in biomedical area have been increased. thus, the current studies were desi...

the ability of composing a coherent and extended piece of writing in second language is considered as a fundamental factor to convey information and ideas of learners through the academic issues. although learners may achieve a perfect academic writing skill through assigning the l2 tasks in content based instruction, but demonstration of their abilities may be related to their ability in l1 es...

for several years, researchers in familiarity of efl teachers with post-method and its role in second and foreign language learners’ productions have pointed out that the opportunity to plan for a task generally develops language learners’ development (ellis, 2005). it is important to mention that the critical varies in language teaching was shown is the disappearances of the concept of method ...

one of the most important number sequences in mathematics is fibonacci sequence. fibonacci sequence except for mathematics is applied to other branches of science such as physics and arts. in fact, between anesthetics and this sequence there exists a wonderful relation. fibonacci sequence has an importance characteristic which is the golden number. in this thesis, the golden number is observed ...

monumental changes occurring on a daily basis have altered the world into a global village of expanding technology and shrinking geography in which preparing language learners for intercultural communication seems to be a sine qua non for modern language education. employing a cross-sectional design in its first phase, this study investigated the intercultural sensitivity and language proficien...

if the precise implementation of the principle of proportion and:balance between the violation and the penalty as well as the other dimensions could be considered as a stick yard for the imptementation of justice any lack of preciseness in carrying out such principle would not indeed be much too far from injustice . naturally ,if it would be imagined that the objective of balance between...