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...

having conducted the experiment and analysed the data, the researcher computed the groups mean scores and variances for the test relating to the research question. as the final atep, a t-test was conodonted for the hypothesis. as noted earlier, the significance level was determined at .05 and .01 respectively. the observed t-value was higher than the critical t-value at. 5 and .01 levels. conse...

in recent years many researchers have been focused on interaction of small molecules with dna. dna is generally the primary intracellular of anticancer drugs, so the interaction between small molecules and dna can cause dna damage in cancer cells, blocking the division of cancer cells and resulting in cell death. the flavonoids are a large group of polyphenolic natural products that are widely ...

abstract the present study was conducted to investigate the effect of using model essays on the development of writing proficiency of iranian pre-intermediate efl learners. to fulfill the purpose of the study, 55 pre- intermediate learners of parsa language institute were chosen by means of administering proficiency test. based on the results of the pretest, two matched groups, one as the expe...

a problem of computer vision applications is to detect regions of interest under dif- ferent imaging conditions. the state-of-the-art maximally stable extremal regions (mser) detects affine covariant regions by applying all possible thresholds on the input image, and through three main steps including: 1) making a component tree of extremal regions’ evolution (enumeration), 2) obtaining region ...

educational researchers have provided evidence that teachers’ emotional intelligence has strong effects on various aspects of teaching and learning. yet, in the field of teaching english to speakers of other languages (tesol), inquiry into teachers’ emotional intelligence is nearly limited. given its documented powerful impact on teaching practices and student learning, it is critical to pursue...

a significant problem in multicarrier communication systems is the necessity to reduce the value of papr (peak-to-average power ratio) of transmitting signal. in this thesis we study the effect of the system parameters such as coding and modulation types on papr and ultimate ber in a mc-cdma system. in this study we consider fading channel as well as the nonlinearity of transmitter’s amplifier ...

the present study sought to investigate the impact of using mind-mapping technique instruction on female elementary efl learners reading comprehension; it also investigated their attitudes towards using mind-mapping technique as a tool to improve their reading comprehension. this study followed a quasi-experimental design with two intact groups as experimental, and control groups. the participa...

in the new age, in regard to human success in education in the globalizing world, one can consider english proficiency and individual differences as two important issues. in efl settings, reading skill plays an important role in education. it seems that using multiple intelligences theory in efl classes which values individual differences by tapping different intelligences, can be rewarding. as...

learning english is very popular all over the world nowadays and it is considered a high prestigious language among citizens of different societies. one of the most important materials for learning a new language are textbooks. the debate that whether learning a new language is natural and neutral or ideological and influential on people’s worldviews, has always been of great importance.