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The inhibition effect of L-methionine (L-Met) on the corrosion of tin in carbonate medium in presence of chloride ions has been studied by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization technics. Temperature effect on the corrosion behavior with the addition of L-Met studied in the range of temperature from 298 to 328 K. The inhibition efficiency decreases slightly with the increase in the temperature. Results show that L-Met is a good inhibitor and inhibition efficiency reach 82% at 10−3M. The adsorption of this compound on aluminum surface obeys Langmuir’s adsorption isotherm. The kinetic and thermodynamic parameters were determined and discussed. SEM analysis revealed that the addition of inhibitor retards the corrosion processes, where the grain boundary attacks were completely hindered by the adsorbed inhibitor molecules, Applied Journal of Environmental Engineering Science, Vol 4, No 3 (2018)

The effect of L-methionine (L-Met) on the passivation and corrosion inhibition of aluminum alloy was investigated in carbonate medium in presence of chloride ions. This inhibitive action against the corrosion of aluminum in corrosive solution was investigated at 298 K using potentiodynamic polarization curves (PDP), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results obtained from the polarization curves reveal that the aluminum in alkaline medium exhibits a phenomenon of passivation with breakdown of passivity. Temperature effect on the corrosion behavior with the addition of (L-Met) studied in the range of temperature from 298 to 328 K. The inhibition efficiency decreases slightly with the increase in the temperature. Results show that L-Met is a good inhibitor and inhibition efficiency reach 87,23% at 10−3M. The electrochemical results are confirmed by scanning electron microscopy (SEM). The adsorption of this compound on aluminum surface obeys Langmuir’s adsorption isotherm. The kinetic and thermodynamic parameters were determined and discussed., Moroccan Journal of Chemistry, Vol 6, No 2 (2018)

The present study focused on the electrochemical oxidation method to degrade a Fungicide Thiabendazole in an aqueous medium. Galvanostatic electrolysis of Thiabendazole solution was performed on a SnO2 anode. The influence of the electrolyte nature (KCl, NaCl, Na2SO4, and Na2CO3), sodium chloride concentration, and the time of degradation were investigated. The electrochemical treatment process of Thiabendazole was followed by chemical oxygen demand (COD) and UV-visible spectrophotometer measurements. It was observed that the removal of Thiabendazole was only achieved in the case of using NaCl as supporting electrolyte. The results have shown a good degradation of Thiabendazole, which the best obtained conditions for COD (73%) removal on the SnO2 anode are 60mA.cm-2 as current density and 2% of NaCl for four hours as time of treatment., Applied Journal of Environmental Engineering Science, Vol 3, No 3 (2017)

The inhibition potentials of methanol extracts of leaves (GFL) and rind (GFR) of Grapefruit plant was investigated by evaluating the corrosion behaviour of carbon steel metal immersed in 1.0 M HCl solution containing various concentrations of the extracts. Electrochemical technical, Gravimetric measurements and adsorption characterization were utilized to evaluate the corrosion inhibition and adsorption properties of the extracts. The results revealed that the studied extracts were efficient inhibitors of corrosion in carbon steel immersed in 1.0 M HCl and that the inhibition efficiency depends on the concentration of the extracts. The activation energies and the negative free energy of adsorption obtained from the adsorption of methanol extracts of leaves and rind of Grapefruit indicate that the methanol extracts were physically adsorbed on the surface of the carbon steel and that the adsorption is endothermic, spontaneous, strong and fit excellently with the assumptions of the Langmuir adsorption isotherm. The activation parameters are determined and discussed., Moroccan Journal of Chemistry, Vol 5, No 3 (2017)

International audience; Synthesis characterization and hydrogenation behaviour of as quenched Ti 41.5+X Zr 41.5-X Ni 17 (x=0, 3.5, 11.5 and 13.5) nano quasicrystalline ribbons-Lunar Luminescence-Luminescent properties of alumina ceramics doped with chromium oxide-This content was downloaded from IP address 147.94.103.164 on 12/10 Abstract. In this work, a study of the role of chemical substitution in the properties of the solid solution Sr 1-x Pb x WO 4 (x = 0, 0.5 and 1) is presented. Polycrystalline samples were synthesized by solid state reaction at 1100°C. Using Rietveld method, the structural parameters of all samples were refined. All structures are of scheelite type Scanning electron microscopy showed that a high level of crystallization characterized the samples, with modifications in sizes and shapes depending on composition x. The Infrared and Raman spectroscopies were performed to characterize the evolution of vibrational modes with composition x. Finally, a systematic study of luminescence under X-ray and UV excitations was performed. The energies and intensities of luminescence depended on composition x and on the nature of excitations. 1. Introduction The first paragraph after a heading is not indented The scheelite tungstate crystals AWO 4 are characterized by tetragonal structures [1,2] (space group I4 1 /a), with tetrahedral oxyanions WO 4 2-and M 2+ cations forming MO 8 groups [3]. They were extensively investigated for their potential applications as laser host materials [4,5], scintillators [6,7], oxide ion conductors [8], materials for microwave applications [9] and magnetic materials [10]. The luminescent properties under different excitations of single-crystals as well as polycrystalline SrWO 4 and PbWO 4 compounds have been widely studied by several authors [11-15]. Generally, luminescence spectra of scheelite tungstate were decomposed into two main blue and green bands, and to a weaker orange-red emission: the emissions were observed with energies close to 3.0-2.8, 2.7-2.4 and 2.3-2.0 eV [16-20]. In this work we study the luminescent properties of lead and strontium tungstates Sr 1-x Pb x WO 4 for the three compositions x= 0 ; 0.5 and 1 under X-ray and UV excitations. We already published the synthesis, characterization and luminescence under X-ray excitation of Sr 1-x Pb x WO 4 and Ca 1-x Cd x WO 4 solid solutions [21-23]. Presently, we compare the luminescence responses under X-ray and UV excitations of these substituted samples.