Showing papers by "Reza Fazaeli published in 2017"

Quantum Chemical Study of the Solvent Effect on the Anticancer Active Molecule of Iproplatin: Structural, Electronic, and Spectroscopic Properties (IR, 1 H NMR, UV)

Abstract: The structural, electronic, and spectroscopic properties of the anticancer active molecule of iproplatin were investigated in the gas and liquid phases. Based on the polarizable continuum model (PCM), the solvent effect on the structural parameters, frontier orbitals, and spectroscopic parameters of the complex was investigated. The results indicate that the polarity of solvents plays a significant role in the structure and pro perties of the complex. 1H and 13C NMR chemical shifts were calculated using the Gauge-invariant atomic orbital (GIAO) method. Pt–Cl and Pt–OH bonds were investigated through a vibrational analysis. Moreover, time dependent density functional theory (TD-DFT) was used to calculate the energy, oscillatory strength, and wavelength absorption maximum (λmax) of electronic transitions and its nature within the complex.

Empirical modeling and CCD-based RSM optimization of Cd(II) adsorption from aqueous solution on clinoptilolite and bentonite

Abstract: In the present study, adsorption of Cd(II) ion from an aqueous solution on natural clinoptilolite (NC), natural bentonite (NB), modified clinoptilolite (MC) and modified bentonite (MB) were investigated. Response surface methodology (RSM) and central composite design (CCD) were used for NC and NB in order to investigate the effect of pH and contact time on adsorption efficiency and process optimization. Based on statistical analysis, the Cd(II) adsorption model was highly significant, with very low p-values. pH’s 5.35 and 3.89, and contact times 20.49 and 16.27 h, with adsorption efficiency 94.86% and 87.42%, were found to be optimum for Cd(II) ion adsorption on NC and NB, respectively. The experimental data was fitted to adsorption isotherm models, indicating the monolayer sorption of Cd(II). The Jossesns, Unilan, Baudu, and Freundlich models were selected as the best models, with correlation coefficients of 0.8973, 0.9930, 0.9267, and 0.9723, and with lowest error for NC, NB, MC, and MB, respectively, with negligible differences compared to the experimental values. The results showed that the NC adsorption efficiency is higher than NB in both cases.

The effect of cationic surfactant on the structure, morphology and optical band gap of ferrites synthesized by a microwave sol–gel auto-combustion method

Abstract: Cu and Ni ferrites as the semiconductor materials were synthesized by a microwave sol-gel auto-combustion method. Two cationic surfactants, sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB), were applied and the influence of surfactants on the properties of the Cu and Ni ferrite particles was studied. The samples were characterized by X-ray powder diffraction (XRD) pattern, scanning electron microscope analysis (SEM), Fourier transform infrared (FT-IR) spectroscopy and diffuse reflectance spectra (DRS). Powder XRD analysis and FT-IR spectroscopy confirmed the formation of ferrite spinel phase. The crystallite size was calculated to be 50-95 nm using Scherrer’s equation. The morphology and size of the synthesized nanoparticles have been observed by scanning electron microscopy. The particles were agglomerated without using surfactant. Using CTAB leads to the samples with layer shapes, and using SDS leads to the samples with pyramidal shapes. The energy band gaps calculated from UV–DRS absorption by using Kubelka-Munk equation were 1.68-1.77 eV, indicating that band gap of Cu ferrites becomes small and band gap of Ni ferrites becomes large in the presence of surfactant.