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Using UV spectrometry, we studied for the first time the regularities of AlkNHBr consumption in two variations of the formation of 1,2,3-trialkyldiaziridines in aqueous media: by mixing acetaldehyde and AlkNHBr in excess of AlkNH (method 1) and by the reaction of MeCH=NEt with EtNHBr in excess of EtNH (method 2). We determined the rate constants of the individual stages of the reaction. Using quantum chemistry methods (DFT/B3LYP/3-21G), we performed calculations of spatial and electronic structures of the reacting compounds, indices of local reactivity, and global electrophilicity of atoms of the individual reaction intermediates, based on which we explained the decrease in the reaction rate when using EtNHBr instead of MeNHBr in method 1. In method 2, the formation of 1,2-diethyl-3-methyldiaziridine occurs exclusively through the intermediate iminium cation. [ABSTRACT FROM AUTHOR]

Electrochemical oxidation of tetracycline on a boron-doped diamond electrode in order to develop a method for purification of waste water from contamination by pharmaceutical agents was studied. It was found that under these conditions deep oxidation of tetracycline (TC) down to its full mineralization can take place. Using high resolution mass spectrometry, it was shown that in the first stage of the reaction the oxidation of TC proceeds with the formation of products with higher molecular mass than TC, but with further electrolysis TC transforms into compounds with lower molecular mass, and then into inorganic compounds. [ABSTRACT FROM AUTHOR]

Electrochemical oxidation of tetracycline on a boron doped diamond electrode within the stability potentials of water was studied in order to develop an approach for the purification of waste water containing medicinal agents. Cyclic voltammetry, HPLC, and high resolution mass spectrometry were used to establish that in the electrochemical oxidation process, tetracycline adds one oxygen atom to further form organic compounds with molecular weights higher than that of tetracycline. It was found that tetracycline in this region of potentials can be almost completely deactivated without its mineralization. [ABSTRACT FROM AUTHOR]

Abstract: LiGaTe2 crystals have been grown by the Bridgman–Stockbarger technique. The clear transparency range of LiGaTe2 extends from 2.5 to 12μm and its band-gap at room temperature is at 2.41eV (515nm). LiGaTe2 is a positive uniaxial crystal which possesses sufficient birefringence for phase-matching. Its non-linear coefficient d 36 estimated by phase-matched second harmonic generation is 43 pm/V±10% at 4.5μm. The properties of LiGaTe2 are compared to those of other mid-IR chalcopyrite non-linear optical crystals with special emphasis on the frequency doubling potential for CO2 lasers operating at 10.6μm. [Copyright &y& Elsevier]

Abstract  The hydrolysis of acetylsalicylic acid in the anolyte under the conditions of electrolysis was studied. [ABSTRACT FROM AUTHOR]

Abstract  Oxidation of tetracycline® in an electrochemical cell with separated cathodic and anodic compartments on smooth platinum was studied. The extent of electrochemical degradation of tetracycline and the energy consumption for eliminating the biological activity of its aqueous solutions were estimated. [ABSTRACT FROM AUTHOR]