Imidazole-based polyamides (PA)s and polyimides (PI) s were prepared from condensation of a new aromatic heterocyclic diamine, 4,4›(4,4›-(2-(4-(triflouromethyl)phenyl)-1H-imidazole-4,5-dyl)bis(4,1-phenylen))bis(oxy)bis(3-(4,5-diphenyl-1H-imidazole-2-yl)aniline), with various diacids and dianhydrides, respectively. The structure of diamine, PAs and PIs were fully characterized by using elemental analysis, FT-IR, <sup>1</sup>H NMR and <sup>13</sup>C NMR techniques. Also, adsorption capability of these polymers for removal of heavy metal ions such as Co<sup>2+</sup>, Cr<sup>3+</sup>, Cd<sup>2+</sup>, Hg<sup>2+</sup> and Pb<sup>2+</sup> from aqueous solutions was also tested at pH 7-8. The PAs and PIs showed good solubility in aprotic polar organic solvents with high thermal stability exhibiting the glass transition temperatures (T<sub>g</sub>)s and 10% weight loss temperatures (T<sub>10</sub>%) in the range of 220-286 °C and 383-435 °C for PAs and 251-307 °C and 407-512 °C for PIs.
In this study, the feasibility study of Prompt Gamma Neutron
Activation Analysis (PGNAA) experiments at Isfahan Miniature Neutron
Source Reactor (MNSR) has been done using a prototype neutron
beam. This neutron beam was not originally created for this purpose,
but previous studies on this neutron beam have shown that it has
enough neutron flux to carry out some irradiations outside the
reactor core. This prototype neutron beam provided a neutron flux of
order 105 n·cm-2·s-1 and a circular
diameter of 5 cm for the experiments. In addition, an appropriate
setup for High Purity Germanium detector (HPGe) was done at the beam
outlet, where the sample is irradiated. A simple shield was also
installed to prevent radiation damage to the detector. Experiments
were conducted for bulk samples of salt solution with different
concentrations and the prompt gamma spectrums have been obtained and
analyzed.
Proton exchange membrane fuel cells (PEMFC) have received a lot of interest and use metal–organic frameworks (MOF)/polymer nanocomposite membranes. Zeolite imidazole framework-90 (ZIF-90) was employed as an addition in the sulfonated poly (1, 4-phenylene ether-ether-sulfone) (SPEES) matrix in order to investigate the proton conductivity in a novel nanocomposite membrane made of SPEES/ ZIF. The high porosity, free surface, and presence of the aldehyde group in the ZIF-90 nanostructure have a substantial impact on enhancing the mechanical, chemical, thermal, and proton conductivity capabilities of the SPEES/ZIF-90 nanocomposite membranes. The results indicate that the utilization of SPEES/ZIF-90 nanocomposite membranes with 3wt% ZIF-90 resulted in enhanced proton conductivity of up to 160 mS/cm at 90 °C and 98% relative humidity (RH). This is a significant improvement compared to the SPEES membrane which exhibited a proton conductivity of 55 mS/cm under the same conditions, indicating a 1.9-fold increase in performance. Furthermore, the SPEES/ZIF-90/3 membrane exhibited a remarkable 79% improvement in maximum power density, achieving a value of 0.52 W/cm2 at 0.5 V and 98% RH, which is 79% higher than that of the pristine SPEES membrane.
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