An ultrasonication based green synthesis approach was used to prepare curcumin-stabilized silver nanoparticles (c-AgNPs). Nanoparticles thus obtained were characterized by UV-Visible spectroscopy, X-ray diffraction (XRD), Transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). Two different size distributions of c-AgNPs were obtained by changing the ratio of curcumin to silver salt precursor. These c-AgNPs were used as catalysts in the catalytic reduction of p-nitrophenol to p-aminophenol. The c-AgNPs with narrower size distribution exhibited better catalytic activity as well as lower activation energy. Variation of apparent rate constant with the reactant concentration agreed with the Langmuir- Hinshelwood (LH) model. Consequently, the surface rate constant related to the rate-determining step and the respective adsorption constants of p-nitrophenol and of borohydride were determined as per this model.

Three pyridine-based Schiff bases namely N²,N⁶-bis(4-methylbenzylidene)pyridine-2,6-diamine (DAP-1), N²,N⁶-dibenzylidenepyridine-2,6-diamine (DAP-2) and N²,N⁶-bis(4-nitrobenzylidene)pyridine-2,6-diamine (DAP-3) were synthesized, characterized, and their corrosion inhibition performance was studied on mild steel (MS) in 1 M hydrochloric acid solution using electrochemical experiments and theoretical study.The results showed that all the three DAPs act as mixed type corrosion inhibitors, and are adsorbed on MS surface by following Langmuir adsorption isotherm. The methyl-substitutedDAP-1 showed maximum inhibition effiency of 98.5% at 40 mgL^-1. The formation of inhibitor film on MS surface was confirmed by SEM andAFM. Quantum chemical calculations and Monte Carlo simulations were used to understand metal-inhibitor interaction and orientation of adsorption ofDAP molecules.Agood correlationwas observed between theoretical and experimental results.

(2E)-2-(acetylamino)-3-(4-nitrophenyl)prop-2-enoic acid (NPP) was synthesized following a facile chemical method from 4-nitrobenzaldehyde (NB) and thoroughly characterized using spectroscopic techniques. These compounds were applied as novel inhibitors for corrosion of mild steel in 1M HCl using various methods such as absorbance difference, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). The results indicate that these inhibitors show an excellent protection performance and achieve the corrosion inhibition efficiency values of 94% and 84% for NPP and NB, respectively. Theadsorption of these molecules obeys the El-Awady isotherm model. The surface analysis of mild steel was investigated using scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) methods. Furthermore, quantum chemical calculations were investigated using DFT method at B3LYP/6-31G (d,p)computed by Gaussian 09 showing a good correlation with the experimental results