V. L. Zephirov - Head of Research Team, FSUE FRPC - Measuring System Research Institute n.a. Yu.Ye. Sedakov - (Nizhny Novgorod). E-mail: vzefirov@niiis.nnov.ru L. I. Bakina - Process Engineer, FSUE FRPC - Measuring System Research Institute n.a. Yu.Ye. Sedakov - (Nizhny Novgorod) Ye. A. Zakharychev - Ph.D. (Chem.), Senior Research Scientist of Chromatography, Mass Spectrometry and Elemental Analysis La-boratory, Chemistry Research Institute of Nizhny Novgorod State University n.a. N.I. Lobachevsky. E-mail: zakharychev@list.ru