Kinetics and mechanism of oxidation of β-alanine by peroxomonosulfate (PMS) in the presence of Cu(II) ion at pH 4.2 (acetic acid/sodium acetate) has been studied. Autocatalysis was observed only in the presence of copper(II) ion, and this was explained due to the formation of hydroperoxide intermediate. The rate constant for the catalyzed (k obs 2 ) and uncatalyzed (k obs 1 ) reaction has been calculated. The kinetic data obtained reveal that both the reactions are first order with respect to [PMS]. k obs 1 values initially increase with the increase in [β-alanine] and reach a limiting value, but k obs 2 values decrease with the increase in [β-alanine]. k obs 1 values increase linearly with the increase in [Cu(II)], whereas k obs 2 values increase with [Cu(II)] 2 . Furthermore, k obs 1 values are independent of [acetate], but k obs 2 values decrease with the increase in acetate. A suitable mechanism has been proposed to explain the experimental observation. The reaction has been studied at different temperatures, and the activation parameters are calculated. C 2007 Wiley Periodicals, Inc. Int J Chem Kinet 40: 44-49, 2008

The Corrosion inhibition efficiency of an inhibitor namely Nickel complex of 1-(8-hydroxy quinolin-2yl methyl) thiourea (Ni-HTF) in controlling corrosion of mild steel immersed in aqueous solution containing 60 ppm Cl- has been investigated by polarization method. The formulation consisting of 60 ppm of Cl- and 50 ppm of Ni-HTF offers good inhibition efficiency of 80 %. Polarization study reveals that this formulation functions as a cathodic inhibitor. UV-Visible spectral analysis was used to detect the presence of iron-inhibitor complex. The surface morphology has been analyzed by SEM and EDAX.

In aqueous solution of 0.5M H2SO4, the Annona Squamosa extract was systematically analyzed to ensure its inhibition mechanism by using potentiodynamics polarization, the weight loss method, and electrochemical impedance spectroscopy (EIS) and its inhibitory effect on mild steel corrosion. For mild steel corrosion in 0.5 M H2SO4 solution, its inhibition efficiency increases and decreases with an increase in its concentration and temperature, respectively. Potentiodynamic polarization analyses revealed that the Annona Squamosa behaves as a cathodic inhibitor. In presence of Annona Squamosa extract in 0.5 M H2SO4 solution, an increase in the activation energy of corrosion leads to a decrease in the rate of mild steel corrosion. On mild steel surfaces, the adsorption behaviour of the extract conformed to the Temkin isotherm, Langmuir isotherm and Arrhenius equation. The EIS results were correlated with the polarization findings. According to atomic force microscopy (AFM) and scanning electron microscopy (SEM), the inhibition of mild steel corrosion proceeds through the adsorption of the extract on the mild steel surface.