ABSTRACT. In the present work, herbicide 2,4,5-trichlorophenoxyacetic acid, more commonly known as 2,4,5-T herbicide, has been completely mineralized (i.e. transformed into CO 2 and H 2 O) in saturated aqueous solutions using a semi-industrial electrochemical cell that contains a boron doped diamond anode and a zirconium cathode. We have performed cyclic voltammetry, chronoamperometry and bulk electrolysis to give the optimization characteristics of the degradation of such a compound and its by-products. Bulk electrolysis in the potential region of electrolyte decomposition leads to the complete destruction of 2,4,5-T and its degradation intermediates by means of the electrogeneration of the highly reactive hydroxyl radicals. The evolution of the chemical oxygen demand (COD) and the instant current efficiency (ICE) during the degradation process is perfectly predicted by a theoretical mathematical model. HPLC and GC-MS have also been performed to highlight the evolution of the mother product and its degradation intermediates. Kinetic analysis of the obtained results has shown a fast destruction of the mother herbicide asserting a diffusion-controlled process. 2,4,5-trichlorophenol and quinonebased organic compounds have been depicted as aromatic intermediates, all of them transformed into short chains carboxylic acids before complete mineralization happens.

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The tridentate N 4 -type Schiff base was synthesized from the condensation reaction of 2-hydrazinopyridine and pyridine-2-carbaldehyde. Neodymium and Samarium complexes were isolated when the corresponding nitrate salt was added to the solution of the ligand. The isolated compounds were characterized by elemental analyses, IR study, room temperature magnetic measurements and single X-ray crystal diffraction of the two crystals. Both complexes crystallize in the monoclinic system with space group P21/c. KEYWORDSLanthanide complexes, hydrazino, antioxidant activity, X-ray structure.

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We report accurate photoionization calculations of resonance energies and widths of the 2pns 1P° and 2pnd 1P° Rydberg series (n = 4–25) of the Be-like ions (Z = 8–18). Calculations are performed using the screening constant by unit nuclear charge (SCUNC) method. The results are analyzed in the framework of the standard quantum defect theory, as well as of the SCUNC-procedure, by evaluating the effective nuclear charge. The results for Na7+ to Ar14+ ions are believed to be the first theoretical data. Those for O4+, F5+ and Ne6+ ions compare well with the available theoretical results. The new data obtained may provide useful guidelines for future photoionization studies on Be-like ions with Z = 11–18.