Papers by Author: Seyed Javad Ahmadi

Abstract: An efficient method for the synthesis of 4-amino-5-pyrimidinecarbonitriles by three-component reaction of malononitrile, aldehydes and N-unsubstituted amidines, under aqueous conditions, using CuO nanoparticles as catalyst is reported. The protocol offers advantages in terms of higher yields, short reaction times, and mild reaction conditions, with reusability of the catalyst.

Abstract: By a single-step supercritical hydrothermal synthesis method, yttrium oxide nanoparticles were successfully prepared without additional treatment. Yttrium oxide nanoparticles were employed as an adsorbent to study the adsorption of some heavy metal ions. This study revealed that nano structure yttrium oxide was an effective adsorbent for removal of lead ions from aqueous solutions.

Abstract: In order to investigate the effect of bentonite binder on adsorption and cation exchange properties of granulated nano NaY zeolite, the adsorption of Xe and N2 and removal of Sr2+ ion from aqueous solution was studied. The results showed that increase in bentonite content of granules from 20 to 40 weight percent caused increase in the rupture load of granules by 232%, decrease in BET surface area by 66% and lower the Sr²⁺ uptake percentage by 35%. The Henry’s law constant, heat of adsorption, effective crystal diffusivity as well as activation energy of diffusion of Xe over granulated nano NaY with 25% bentonite was also measured by pulse chromatography method. Obtained results were compared with similar results of binderless micron sized NaY material. Results indicated that although the adsorption of xenon on the binder of bentonite was negligible, the diffusion resistance created by this binder was significant such that the effective crystal diffusivity in the granules with 25% binder determined to be 4302 percent lower than the granules with no binder.