Synthesis of glyoxylic acid was carried out by oxidation of glyoxal aqueous solutions by nitric acid. Glyoxylic acid and oxalic acid (as a by-product) were isolated from technological mixtures in the form of their calcium salts in a strictly defined region of pH. Previously, model calcium salts were synthesized from the commercial acids as reference objects.The results of infrared spectroscopy and complexometric titration of precipitates of calcium salts of glyoxylic and oxalic acids, isolated in various pH regions, allow one to construct reliable research strategies of complex mixtures, such as obtained from the oxidation products of aqueous solutions of glyoxal.

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Electron beam processing is one of the effective methods for modification of surface material properties. Influence of electron beam irradiation on the structure of polymeric materials such as polyvinyl alcohol and polylactic acid was investigated. Electron beam processing was carried out at 8 kV accelerating voltage and a pressure of 3 x 10-2 Torr, the emission current was from 25 to 40 A, the pulse duration was from 150 to 300 μs and the pulse number was from 1 to 10. The elemental composition and the structural state of the surface of irradiated polymer materials were studied by infrared spectroscopy (IR-spectroscopy), X-ray photoelectron spectroscopy (XPS), scanning-electron microscopy (SEM) and atomic-force microscopy (AFM) methods. It was established that certain chemical processes take place and some physicochemical properties change under electron treatment.

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