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Background: Copper is a metal that is widely used in many fields such as industry and construction, etc. These different industrial sectors use acid solutions such as nitric acid and hydrochloric acid, etc. The use of acid solutions in the industrial environment causes degradation of materials. In recent decades, the use of corrosion inhibitors has become very essential. Objective: The objective of our study is to test the performance of meloxicam as a copper corrosion inhibitor in a nitric acid medium. Methods: The studies were conducted using the gravimetric method and density functional theory (DFT) at B3LYP/6-311G (d, p) level of theory. The inhibitory efficiency of the molecule increases with increasing concentration of Meloxicam, but decreases with increasing temperature. The adsorption of the molecule on the copper surface follows the Villamil model. Results: The thermodynamic quantities of adsorption and activation were determined and discussed. Quantum chemical calculations have allowed determining the molecular descriptors. Conclusion: There is a good agreement between the experimental and theoretical results. Electrochemical studies are envisaged.

Atenolol was examined as a copper corrosion inhibitor in 1M nitric acid solution using the mass loss technique and quantum chemical studies, based on density functional theory (DFT) at the B3LYP level with the base 6-311G (d,p). The inhibitory efficiency of the molecule increases with increasing concentration and temperature. The adsorption of the molecule on the copper surface follows the modified Langmuir model. The thermodynamic quantities of adsorption and activation were determined and discussed. The calculated quantum chemical parameters related to the inhibition efficiency are the energy of the highest occupied molecular orbital E(HOMO), the energy of the lowest unoccupied molecular orbital E(LUMO), the HOMO-LUMO energy gap, the hardness (η), softness (S), dipole moment (μ), electron affinity (A), ionization energy (I), absolute electronegativity (χ),absolute electronegativity (χ), fraction (ΔN) of electrons transferred from Atenolol to copper and electrophilicity index(ω). The local reactivity was analyzed through the condensed Fukui function and condensed softness indices to determine the nucleophilic and electrophilic attack sites. There is good agreement between the experimental and theoretical results.

Ruthenium complexes present two states of oxidation that are Ru(II) and Ru(III). Both are assumed to present cytotoxic activity at ground state. On the purpose of highlighting their differences, DFT, TD-DFT and NBO have been performed at both Wb97xd/Lanl2dz and B3lyp/Lanl2dz levels. NBO program shows that both groups of ruthenium complexes present almost the same charge of Ru atom. Moreover, they display nearly the same structure of valence orbitals of the ruthenium. However, when it comes to compare their frontier orbitals HOMO and LUMO, we notice that the chloride atom has a great influence on their energy. The lack of Chloride atoms reduces the energy of frontier orbitals regardless of the functional. And the more the number of chloride atoms, the higher the energy. Also, RuCl3Terpy and α-RuCl2(Azpy)2 have been discovered to display the best energy suitable for reaction as cytotoxic agents. Yet, both are from groups different. Thus, at ground state, there is practically no difference between both groups. However, regarding TDDFT prediction with the determination of vertical electronic affinity VEA and vertical ionization potential VIP both at ground state S and at exciting T1 state, we notice that Ru(II) complexes are not active either in the presence or absence of 3O2 molecule. Here, only Ru(III) complexes are able to react on Guanine through their radical cations or by generating the superoxide radical anion . Therefore, the Ru(III) complexes are assumed to be active both at a fundamental state and under the effect of light for photodynamic therapy. We come to conclude that Ru(II) complexes are not active by excitation as their valence electrons are paired thereby making these complexes more stable. Besides, , a Ru(II) molecule that is not active at ground state owing certainly to its C3 symmetry or Azpy ligand presents all the same a difficult activity on generating . For the coming paper, we intend to check whether Ru(II) complex can be active under the effect of light if it is in a triplet charge state.

The development of societies and industrial progress cannot be achieved without the use of electricity. The growing demand for energy and the degradation of the environment by current sources force us to look for other methods to produce it. The production of renewable energy from landfill waste reduces the environmental problems caused by the combustion of coal, oil and natural gas. Therefore, in this work, life cycle assement is used to compare the different energy recovery options of four solid waste management systems with each other and to assess the corresponding carbon credit. The four management systems are: landfilling (scenario S0), landfilling with energy recovery (scenario S1), incineration combined with anaerobic digestion with energy recovery in both cases (scenario S2) and incineration with energy recovery (scenario S3). The assessment showed that scenario S2 is the best waste management option for energy production with an energy potential of 890.9 GWh/year, which corresponds to 11% of the Cote d’Ivoire's net electricity production in 2015. In addition, this scenario has led to a better reduction in methane emissions with a carbon credit of USD 12168200 for the total amount of waste managed in one year. However, scenario S1 is the wrong option in terms of energy production with an energy potential of 232.2 GWh/year corresponding to 3% of the Ivory Coast's net electricity production in 2015. Regarding the potential reductions in CO2equivalent emissions, those of scenario S1 are the lowest with a carbon credit of US$ 12,025,343. From the point of view of the production of clean and green energy, the voice to be followed for an optimal MSW management technique in Abidjan is the anaerobic digestion of the organic fraction, the incineration of the fuel fraction, followed by the landfilling of the residues.