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Electrolysis in aqueous 1 M HClO4 and 1 M H2SO4 solutions has been carried out under galvanostatic conditions using boron-doped diamond electrodes (BDD). Analyses of the oxidation products have shown that in 1 M HClO4 the main reaction is oxygen evolution, while in H2SO4 the main reaction is the formation of H2S2O8. In both electrolytes small amounts of O3 and H2O2 are formed. Finally, a simplified mechanism involving hydroxyl radicals formed by water discharge has been proposed for water oxidation on boron-doped diamond anodes

This work deals with the physicochemical and microbiological characterization of a hospital wastewater that is directly discharged in water bodies without treatment. Our focus was paid on the teaching hospital of Treichville (Cote d’Ivoire). For the purpose various physicochemical parameters such as temperature pH dissolved oxygen total dissolved solid conductivity nitrate phosphate chloride chemical oxygen demand (COD) biological oxygen demand for five days (BOD5) salinity and total suspended solids have been assessed. For the microbiological investigations the parameters consisting in Pseudomonas aeruginosa Salmonella and total coliforms have been assessed. From the analysis it has been found that the wastewaters of the teaching hospital of Treichville are highly loaded in organic pollutants and in pathogens bacteria. The values of nitrate dissolved oxygen demand COD BOD5 and biological parameters do not respect the international (WHO) values recommended for the water to be discharged in the environment. The ratio COD/BOD5 has been determined to vary between 1.25 and 2.80. The results showed that the studied wastewater is a domestic type wastewater composed either by mostly biodegradable pollutants or a mixture of biodegradable and non biodegradable organic pollutants. These wastewaters constitute therefore a risk for the populations since they are discharged in water bodies without any treatment and used by communities. Keywords:Physicochemical Parameter Chemical Oxygen Demand Hospital Wastewater Pseudomonas aeruginosa Salmonella

In this work a ruthenium dioxide electrode has been prepared by thermal decomposition at 400oC then used for the oxidation of commercial amoxicillin. The physical characterization showed that RuO2 electrode presents a mud cracked structure. Its electrochemical characterization has revealed an increase of the voltammetric charge in acid electrolyte compared to neutral electrolyte indicating the importance of protons in its surface redox processes. The voltammetric study of the oxidation of amoxicillin has been investigated. It has been obtained that the oxidation of amoxicillin is controlled by both adsorption and diffusion processes. Moreover the oxidation of amoxicillin occurs via direct and indirect processes in free or electrolyte containing chlorides. Through preparative electrolysis enhancement of amoxicillin oxidation was observed in the presence of chloride where the amoxicillin degradation yield reached more than 50 compared to less than 5 in the absence of chlorides. Spectrophotometric investigations have revealed the degradation of intermediates absorbing at 350 nm. Keywords : amoxicillin oxidation perchlorate electrolysis current density ruthenium dioxide

The degradation of ceftriaxone (CTX) has been studied by the electrochemical oxidation processes in an ideally stirred batch reactor using a boron doped diamond (BDD) as the anode. The mineralization of CTX was investigated by UV vis measurements and chemical oxygen demand (COD) analysis. The removal efficiency was studied as a function of several operational variables such as current densities initial CTX concentration initial pH values and inorganic ions. It was found that BDD electrode exhibited good mineralization capability of CTX in neutral conditions at a current density of 100 mAcm ². That oxidation is mainly caused by hydroxyl radicals produced through water discharge at BDD surface in aqueous solution of potassium perchlorate. In presence of nitrate no improvement of the CTX removal was observed but in presence of phosphate and chloride ions CTX removal yield was enhanced. That enhancement was explained to be due by the involvement of in situ produced reactive (oxidative) species such as chlorine and phosphate radicals in the oxidation of the organic compound in the bulk of the solution. Keywords: Ceftriaxone; Boron Doped Diamond; Chemical Oxygen Demand; Oxidation

Une enquête sérologique par hémagglutination indirecte a été réalisée sur 554 moutons et 488 chèvres de différents pays africains. Les taux de prévalence sont variables selon les groupes. Pour le mouton, ils sont inférieurs à 30 % pour tous les pays secs : Bénin 0 %, Sénégal 11,5 %, Djibouti 12,5 %, Niger 19,5 %, Burkina Faso 23 %, Éthiopie 25,6 %. La prévalence atteint 68 % en Côte d'Ivoire. Pour les chèvres, il en est de même : Sénégal 3,5 %, Éthiopie 19,5 % et Djibouti 21 ou 31,4 % selon qu'il s'agit de prélèvement en abattoir ou en ferme. Aucun cas d'avortement toxoplasmique n'a été suspecté dans les pays d'où proviennent les prélèvements, ce qui n'est pas le cas dans d'autres pays où la prévalence est élevée.