Oxidative stability of oils extracted from intact and dehulled sesame seeds was determined by monitoring changes in fatty acid composition, iodine value (IV), peroxide value (PV), conjugated diene (CD), para-anisidine value (p-AV), and 2-thiobarbituric acid (TBA) value and by nuclear magnetic resonance spectroscopy after storage under Schaal oven conditions at 65°C for up to 35 d. The oils from coated seeds were more stable, as reflected in PV, CD, p-AV and TBA values, than those extracted from dehulled seeds after roasting at 200°C, steaming at 100°C, roasting at 200°C plus steaming, or microwaving at 2450 MHz, except for TBA values of oil from microwaved seeds. After 35 d of storage at 65°C, the CD, p-AV, and TBA values of extracted oil from dehulled microwaved seeds were 17.72, 10.20, and 1.22, respectively, while those of their coated counterparts were significantly (P < 0.05) different at 14.20, 16.47, and 1.26, respectively. Few significant changes were evident in the fatty acid composition of oil obtained from either coated and dehulled seeds subjected to different treatments. Nuclear magnetic resonance analyses found that R ao (aliphatic to olefinic protons) and R ad (aliphatic to diallylmethylene protons) ratios increased steadily over the entire storage period, which indicated progressive oxidation of unsaturated fatty acids. JAOCS 74, 215-221 (1997).

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Three nanomaterials based on polyaniline (PANI) are prepared on indium tin oxide (ITO) and applied as electrodes for H2 generation due to the water‐splitting process. PANI/ITO films are prepared using oxidation polymerization method at 25°C, then coated with Au nanoparticles with different thicknesses (sputter time from 1 to 2 min). The three prepared electrodes; PANI/ITO (Electrode (0), 1‐min‐Au/PANI/ITO (Electrode (I)), and 2‐min‐Au/PANI/ITO (Electrode (II)) are compared for H2 generation from H2O. Scanning electron microscope, X‐ray diffraction, UV‐Vis spectrophotometer, and Fourier‐transform infrared spectroscopy analyses have been carried out, in which the average PANI crystal size was ~20 nm. Moreover, the bandgaps were determined, in which 2‐min‐Au/PANI/ITO has the optimum bandgap of 2.25 eV. The characteristic behavior of the H2 generation took place depending on the current density (Jph) value by using Jph–V and Jph–time study. Also, the incident photon‐to‐current conversion efficiency (IPCE) and the applied bias photon‐to‐current efficiency (ABPE) were calculated for the Electrode (II) at 25°C. The optimum IPCE and ABPE efficiency were 18.7 and 0.99%, respectively, at 390 nm. By increasing the temperature to 70°C, the IPCE efficiency increases to about 37%. Finally, activation energy (Ea), enthalpy (ΔH*), and entropy (ΔS*) were determined, in which the values were 24.32 kJ mol−1, 10.90 kJ mol−1, and 74.99 J K−1 mol−1, respectively. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13146, 2019

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