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 the influence of cation?? and anion?? interactions on the strength and nature of n…h hydrogen bond has been investigated by quantum chemical calculations in s-triazine…3hf complex. ab initio calculations were performed at mp2/6-311++g(d,p) level of theory. the natural bond orbital (nbo) analysis and the bader’s quantum theory of atoms in molecules (aim) were also used to elucidate t...

abstract this mixed method study examines whether there is any relationship among the variables of the study (job satisfaction, social capital and motivation). the researcher considered job satisfaction and social capital as independent variables; motivation is the dependent variable of the study. the researcher applied a questionnaire to assess each variable. to measure efl teachers’ job sati...

this study was an attempt to investigate the effect of using c-test passages on the reading comprehension and incidental vocabulary learning of iranian intermediate efl learners. the participants were 60 male efl learners at kish mehr institute in garmsar. in fact, there were two groups, an experimental group and a comparison group with 30 students in each. the participants were pretested throu...

the speech act of disagreement has been one of the speech acts that has received the least attention in the field of pragmatics. this study investigates the ways power relations, social distance, formality of the context, gender, and language proficiency (for efl learners) influence disagreement and politeness strategies. the participants of the study were 200 male and female native persian s...

the present study aimed at investigating how different news agencies using the concept of legitimation/delegitimation represent the same event differently. to this end, van leeuwens (2008) legitimatory/delegitimatory framework was applied to the data gleaned from the iranian state-run news agency fars news, british state-run news agency bbc, and also american state-run news agency voa. the resu...

asymmetric polyethersulfone (pes) microfiltration flat sheet membranes were composed by the phase inversion method (pim) and were used as supports. composite membranes were fabricated by coating silicone rubber as selective layer. effect of different concentrations of pes and pdms and different solvent such as nmp, dmf and dms effects as pes solvents and support thickness and different coagulat...

with the increasing population and the need for more food, as well as with the development of science and technology, human approach to unnatural and often chemical inputs to increase agricultural production has been a great expansion and problems such as increased cancers, chronic diseases has created environmental pollution. implementation of organic organic is a solution to these problems . ...

the present study was an attempt to determine the types of motivation and levels of foreign language learning anxiety among efl students studying at azad and state universities in kermanshah and to determine the relationship between these two factors and language proficiency and gender. to this end, the foreign language learning motivation scale, by deci and ryan )1985(, were administered to 12...

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...