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The algae composition of Euglenophyta division of the steppe river Karasuk has been studied. 94 species, 27 varieties and forms from 16 genera, 5 families, 2 orders and 1 class have been found.  Zonal peculiarities of the taxonomic structure of the division, have been noted, the distribution pattern of euglenophytes across ecotopes is shown, their role in the phytoplankton numbers and biomass has been estimated, and attachment of species of this division to sites of the river with an increased biotic contamination has been established.

Data on rare or new (for West Siberia) algae (38 species and 5 varieties) found in 1995

The paper represents the first report on the algal flora of the lake Uvs-Nuur (Tuva Republic, Russia) in which 202 specific and intraspecific taxa belonging to five divisions have been found. Diatoms and blue-green algae dominate in the lake. The results of systematic and ecological analysis of the lake algae are presented.

A taxonomic analysis of plankton communities of algae in the water bodies of the Molodo river (left-hand tributary of the Lena river) has been carried out. Characteristics of quantitative development of plankton algae of various water bodies of the river basin and the composition of structure-forming complexes are given. It has been established that the influence of precious metal extraction activities of the complex on the phytoplankton in the site of studies is limited by the settler water body.

A new mode of reproduction of Asterionella formosa is discovered in living natural material. The new data on the reproduction of plankton diatom improve our understanding of the biology and ecology of the species. Original micrographs of consecutive stages of development of sister cells were obtained using light microscope

The mechanism of decomposition of artificial scheelite in nitric acid is investigated by recording the curves of anodic charging. This method involves fixation of temporal changes in the potential of platinum electrode in reaction medium. It is established that the reaction between artificial scheelite and nitric acid is not a solid-phase process but a usual exchange reaction in aqueous medium with the dissolution of scheelite and formation of precipitate which is tungsten trioxide monohydrate.

Known hypotheses concerning the mechanism of formation of aromatic aldehydes (vanillin and syringaldehyde) in the processes of oxidative cleavage of lignins are discussed. A new mechanism of lignin oxidation is described, which starts from the formation of phenoxyl radical and is completed by the formation of vanillin through the retro-aldol cleavage of substituted coniferyl aldehyde. Oxidation of the model compounds is studied and experimental confirmations of the proposed mechanism are obtained. Coniferyl alcohol, the postulated intermediate of eugenol oxidation, was detected by GC-MS. Comparison of the kinetics and oxidation products of vanillidenacetone and lignosulphonates, eugenol and isoeugenol, guaiacyl ethanol and quaiacyl propanol confirms the proposed mechanism. On its basis, possibilities are found to elevate the selectivity of lignin oxidation by oxygen into aromatic aldehydes by accelerating the process due to tightening conditions.

In relation to the problem of recovery of fission palladium from highly active liquid wastes from spent nuclear fuel reprocessing, the efficiency of a flow sheet based on solvent extraction and electrochemical processes for palladium purification from a number of accompanying elements (Ag, Te, Se, Sb) was tested using model (in the absence of radiation) nitrate-nitrite solutions. The flow sheet is composed of two extraction cycles which involve solvent extraction of palladium with petroleum sulphides, washing of the extracts with acid solutions, and palladium stripping with aqueous ammonia. In the first cycle imitating recovery from HLW, ~99 % Pd and ~25 % Ag is recovered and separation from other accompanying elements is achieved. High efficiency of palladium separation from silver (10⁵) is achieved during the second cycle due to solvent extraction affining from hydrochloric solution. For passing from the ammonia strip liquor of palladium and silver, which is the final product of the first cycle, to the starting hydrochloric solution for the second cycle, electrochemical operations are applied, involving co-deposition of these metals on the cathode followed by their anodic dissolution in HCl solution. The efficiency of these operations was also not less than 99 %. At the final stage, purified palladium is recovered from the strip liquor of the second cycle as a difficultly soluble trans-dichlorodiammine ("palladozammine", PZA). End-to-end palladium fraction extracted with the help of this flow sheet is 97_98 %. No Te, Se or Sb admixtures were detected in the resulting PZA; Ag content is close to the level observed in the reference experiment (mass concentration 10^_5 %).

Using a multi-stage scheme including different sequences of the stages of magnetic separation, hydrodynamic and granulometric classification, magnetic microspheres of fixed composition containing the magnetic constituent at the level of 95_99 % were separated from the fly ash of coal from the Ekibastuz and Kuznetsk basins. The yield, texture characteristics, macrocomponent and mineral phase composition were determined and globules of three morphological types were described for close-cut fractions of magnetic microspheres. A general dependence of the properties of close-cut fractions of microspheres on ferric oxide content was revealed. It was demonstrated that for the mass concentration of total Fe₂O₃ >60 %, mainly massive microspheres with various crystal microstructure are formed. With a decrease in iron content, the formation of porous microspheres becomes predominant. It is established that the governing factor in the formation of microspheres of morphological type is the viscosity of ferriferous silicate melt.

The composition of Coumarin compounds from roots of Peucedanum morisonii is investigated, 13 individual components are isolated and characterized.