Optical density and atomic ratios N/S of humic acids of bottom sediments of lakes of the Middle Ob region

Abstract

The paper presents the results of studies of the optical density of alkaline solutions of humic acids (HA) and himatomelanic acids (MMC) characteristic of the Middle Ob bottom sediments of lakes of silicate, organo-silicate and organic class and their dependence on the atomic ratios of H/S of HA macromolecules. It is established that the results of spectroscopy of the UV and visible regions of the HA spectrum depend on the results of the elemental composition. With an increase in the atomic ratios of N/S, the values of E465 quantities (quasi-extinction coefficients) decrease, which reflects the composition of the aromatic part of GC macromolecules. MMCs have been studied, however, they contain more peripheral groups than GC and do not have patterns of the relationship of E465 quantities from N/S, therefore, correlation dependencies are not given in the article. The highest content of aromatic carbon in GC was found for samples of GC K-6 of the silicate class of the Kondinsky province (left bank of the Ob) and C-5 of the organic class of the Sredneob province (right bank of the Ob). The general correlation dependence of N/S and E465 values is higher in the samples of the GK of the Kondinsky province. Keywords: SAPROPEL, HUMIC ACIDS, HIMATOMELANIC ACIDS, UV SPECTROSCOPY, MIDDLE OB