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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.

International audience

Argan Cake Extract (ACE) is reported as corrosion inhibitor of copper in 2 M H3PO4 and NaCl. Weight loss measurements, Tafel polarization and electrochemical impedance spectroscopy techniques were employed to analyze the effect on copper corrosion. Our results showed, a significant decrease in corrosion rate copper corrosion in the presence of Argan cake extract as an inhibitor. The maximum potential of the extract was obtained at 4g/L-1, with 89% efficiency. Results obtained from potentiodynamic polarization, impedance measurements and gravimetric method were also in good agreement., Applied Journal of Environmental Engineering Science, Vol 2, No 1 (2016)

In this work we studied the inhibition effect of two inhibitors 2-Nitrobenzaldehyde (NBA) and 4-Nitrophenol (PN) on the corrosion of carbon steel (CS) in 0.5 M H2SO4 by weight loss measurement, potentiodynamic polarization methods and electrochemical impedance spectroscopy (EIS) techniques. The results showed that the two inhibitors were a good inhibitors in 0.5 M H2SO4, and their adsorption on the carbon steel surface follows the Langmuir isotherm model in acidic media. The results obtained from the different corrosion evaluation techniques are in good agreement. Polarization curves showed that the inhibitors acted as mixed-type inhibitors in sulfuric acid. Changes in impedance parameters (charge transfer resistance Rct, and double-layer capacitance, Cdl) were indicative of adsorption of the inhibitors on the metal surface, leading to the formation of a protective film. The inhibition efficiency increases with inhibitors concentration to attain the maximum value of 93.46% for NBA and 85.91% for PN at 10−3M. The effect of the temperature on the corrosion behavior with addition of 10-3M of the inhibitors was studied in the range 298-328 K, and some thermodynamic functions of dissolution processes were also determined and discussed. The electronic properties such as the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) energy levels, energy gap (LUMO-HOMO), dipole moment and molecular orbital densities were computed., Applied Journal of Environmental Engineering Science, Vol 2, No 2 (2016)

Copper (I) oxide polycrystalline thin films (Cu2O) were synthesized by cathodic electrochemical process. The solution was prepared from a basic solution of copper sulfate using tartaric acid as a stabilizer. The structural characteristics have been studied by X-ray diffraction “XRD” for phase composition and crystallinity. Particle sizes, morphology and elemental composition of cuprite thin films were examined by scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). The results indicated that Cu2O samples retained a cubic structure. The morphologies of electrodeposited samples consisted of different shapes depending on the studied parameters such as current density, bath temperature and nature of substrate., Applied Journal of Environmental Engineering Science, Vol 1, No 1 (2015)

This work investigated the electrocatalytic degradation of an azo dye by electrochemical oxidation on copper oxide anode. The influence current density, time of electrolysis, temperature, the conductive salt concentration and the initial dye concentrations were critically examined. The results of these influences are expressed in terms of Chemical Oxygen Demand (COD removal). Also, both of the current efficiency and power consumption values are calculated. In this paper we report that, the highest electrocatalytic activity was achieved in the presence of NaCl (0.1 M), 50 mA/cm2, pH of 3 and temperature of 30 °C. The highest electroactivity could be attributed to the contribution from direct oxidation via reaction of this dye with the electrogenerated hydroxyl radicals adsorbed on the copper oxide surface., Applied Journal of Environmental Engineering Science, Vol 1, No 1 (2015)

International audience; In Morocco, air pollution is mainly due to road traffic and industrial sources. Until today, only standard gases such as NO, NO2 CO, SO2 and O3, as well as PM10, are continuously monitored in the Moroccan large cities. VOC measurements are very rare. This paper presents for the first time the results of measurement campaigns of BTX in a small town with industrial character, Anza locality, located 7 km northwest of the city of Agadir (southwestern Morocco). The BTX measurements were conducted from February 2012 to November 2012. Benzene, toluene, and the three isomers of xylene were quantified in ambient air in four places carefully selected to reflect the main activities in the city. The outdoor average concentrations of benzene, toluene and xylenes were 12.9 μ g.m-3, 36.9 μ g.m-3 and 16.2 μ g.m-3 respectively. No seasonal variation was observed. The fluctuation concentrations are attributed to starting up of the activities and variations flow of cars. The wind is the meteorological factor which drives the observed results. An important decrease of the BTX concentrations was observed in 2012 compared to the values obtained in 2007.

The main applications of activated carbon are among other purification, decolorization, deodorization and general detoxification of drinking water and the purification of air and chemicals, food ... etc. The research focused on the adsorption of acetic acid on activated carbon. Studies in "batch methods" were used to determine the contact time (4 hour to 16,5% in removal efficiency and a concentration of 0,2 mol/l of substrate). However, this contact time may vary with the concentration of organic molecule. The influence of parameters such as: temperature, concentration of adsorbate in solution, time, mass of adsorbent and pH, revealed a significant improvement in capacity and speed acid adsorption acetic on this support. Moreover, adsorption of this compound is well described by kinetic models of Langmuir and Freundlich.Also the comparison of activated carbon with other soils has concluded that the marl calcareous responds well to the adsorption of acetic acid with a removal efficiency of 75 % for a time of 0,5 h., Moroccan Journal of Chemistry, Vol. 2, No 5 (2014): Proceedings of the fourth edition of the International Congress Water, Waste & Environment

Argan Oil (AO) was tested as inhibitor for copper corrosion in 2 M H3PO4 and NaCl 0.3 M. The techniques used in this work were weight loss measurements, potentiodynamic polarisation and Electrochemical Impedance Spectroscopy (EIS). The inhibition efficiency was found to increase with inhibitor content to attain 94% for AO at 7g/L. Inhibition efficiency E (%) obtained from the various methods is in good agreement. The temperature effect on the corrosion behaviour of copper in (2 M H3PO4+ 0.3 M NaCl) was studied by potentiodynamic technique in the range from 298 to 323 K., Moroccan Journal of Chemistry, Vol 2, No 1 (2014)

International audience; Pollution with different types is one of the major problems that threaten our planet. Very large amounts of pollutants are emitted worldwide and cause to the health of the humans and the environment, which will cause a decrease in resources for sustainable development of the planet. It is therefore essential to seek scientific solutions to reduce these hazardous emissions. In this context, the development of new materials to detect and clean up liquid and gas emissions from all sources is inevitable. The rare earth oxides have been used for many years to improve the reactivity, selectivity and stability of the catalysts. These oxides include cerium and bismuth oxide, which have been electrodeposited on several substrates under galvanostatic condition from aqueous solutions. The X-Ray diffraction (XRD) and scanning electron microscopy (SEM) studies revealed that as deposited films are nanocristalline, and the films are porous and the surface morphology changes with variation of several parameters (Current, substrate...).