The inhibition ability of N,N '-bis(2,4-dihydroxyacetophenone)-1,3-propandiimine (DHAPP) as a schiff base against the corrosion of API-5L-X65 in 1 M HCl solution was evaluated by polarization, electrochemical impedance spectroscopy, and scanning electron microscopy. Polarization studies indicated that DHAPP retards both the cathodic and anodic reactions through chemical adsorption and blocking the active corrosion sites. The adsorption of this compound obeyed the Langmuir adsorption isotherm. The inhibition effi ciency increased with inhibitor concentration and decreased with increasing temperature. EIS data analysed to equivalent circuit model showed that as the inhibitor concentration increased the charge transfer resistance of steel increased whilst double layer capacitance decreased. Kinetic and thermodynamic parameters such as activation energy, enthalpy, entropy, and Gibbs free energy of activation and adsorption were calculated. Gibbs free energy indicated that adsorption occurred through physical and spontaneous process. Scanning electron microscopy was used to study the steel surface with and without inhibitor.The inhibition ability of N,N '-bis(2,4-dihydroxyacetophenone)-1,3-propandiimine (DHAPP) as a schiff base against the corrosion of API-5L-X65 in 1 M HCl solution was evaluated by polarization, electrochemical impedance spectroscopy, and scanning electron microscopy. Polarization studies indicated that DHAPP retards both the cathodic and anodic reactions through chemical adsorption and blocking the active corrosion sites. The adsorption of this compound obeyed the Langmuir adsorption isotherm. The inhibition effi ciency increased with inhibitor concentration and decreased with increasing temperature. EIS data analysed to equivalent circuit model showed that as the inhibitor concentration increased the charge transfer resistance of steel increased whilst double layer capacitance decreased. Kinetic and thermodynamic parameters such as activation energy, enthalpy, entropy, and Gibbs free energy of activation and adsorption were calculated. Gibbs free energy indicated that adsorption occurred through physical and spontaneous process. Scanning electron microscopy was used to study the steel surface with and without inhibitor.

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The inhibition ability of N,N-bis(2,4-dihydroxyhydroxybenzaldehyde)-1,3-Propandiimine (DHBP) as a schiff base against the corrosion of API-5L-X65 steel in 1 M HCl solution was evaluated by electrochemical impedance spectroscopy, potentiodynamic polarization and scanning electron microscopy. Electrochemical impedance studies indicated that DHBP inhibited corrosion by blocking the active corrosion sites. The inhibition efficiency increased with increasing inhibitor concentrations. EIS data was analysed to equivalent circuit model and showed that the charge transfer resistance of steel increased with increasing inhibitor concentration whilst the double layer capacitance decreased. The adsorption of this compound obeyed the Langmuir adsorption isotherm. Gibbs free energy of adsorption was calculated and indicated that adsorption occurred through physical and spontaneous process. The corrosion inhibition mechanism was studied by potential of zero charge. Polarization studies indicated that DHBP retards both the cathodic and anodic reactions through adsorption on steel surface. Scanning electron microscopy was used to study the steel surface with and without inhibitor.

A new ligand, 1,5-bis(para methoxyphenyl)-3-ethyl-1,4-pantaazadiene has been synthesized by reaction of the 4-methoxyaniline (panisidine) with ethylamine. The mixture was stirred in an ice bath for 30 min. The structure of the synthesized compound resulted from the IR and 1 HNMR and 13 CNMR. Afterwards, a carbon paste electrode modified with this new ligand was developed for the silver determination at nano molar level concentration. The electerochemical properties of this modified electrode was investigated by employing cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods in an acetate buffer solution (pH=4.8). The effect of pH, scan rate, percentage of modifier and buffer as supporting electrolyte on the electrode process were investigated. The oxidation peak of Ag + was observed at about 0.4-0.5 V. The resulting electrode demonstrated linear response across a 10-9 to 10-8 mol/L-1 of silver concentration range with a detection limit value of 1.61×10-10 mol/L-1 , on the basis of a signal to noise ratio of 3. Relative Standard deviation (RSD%) of the electrode performance was 2.41%. This MCPE, showed high sensitivity and selectivity to Ag + ions in aqueous samples.