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...

among the low–dimensional allotropes of carbon, nanotubes and graphene have attracted very much attention from nano–science and nanotechnology specialists. they have been proposed as building blocks in nanometer device engineering. however, these structures are not defect–free. in this thesis, we focused on defective carbon nanotubes and graphene, and studied the effect of couple of very common...

cement is an essential ingredient in the concrete buildings. for production of cement considerable amount of fossil fuel and electrical energy is consumed. on the other hand for generating one tone of portland cement, nearly one ton of carbon dioxide is released. it shows that 7 percent of the total released carbon dioxide in the world relates to the cement industry. considering ecological issu...

Development of electronic industries, compression of electronic equipment, and removing lead from electronic circuits for environmental issues, resulted in a significant challenge in design and development of tin-based lead-free solders with physical and mechanical properties similar to old tin-lead alloys. In this regard, the set of Sn-Ag-Cu alloys with eutectic and near eutectic compositions ...

Development of electronic industries, compression of electronic equipment, and removing lead from electronic circuits for environmental issues, resulted in a significant challenge in design and development of tin-based lead-free solders with physical and mechanical properties similar to old tin-lead alloys. In this regard, the set of Sn-Ag-Cu alloys with eutectic and near eutectic compositions ...