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Natural halogenated furanones, higher terpenes and steroids comprising three relatively small groups of natural compounds were isolated mainly from sea organisms, as well as from some plant species. The structures of about 90 compounds are considered and the data on the biological activity of some of them are presented.

New efficient lanthanum-containing microfertilizers rendering biopositive prolonged action to nitrification capacity of chestnut soil are obtained by sorption technology. Lanthanum-containing microfertilizers increase the productivity of peas green mass, pepper and tomato fruitage improving their feed and nutritional qualities due to increase in the content of general and protein nitrogen, saccharides, ascorbic acid.

The kinetics of detachment of the acid anions and their transfer into solution is investigated for the preparations of succinic acid obtained mechanochemically. It is established that under the experimental conditions this process goes on almost completely within 1 min for the composites based on talc and for the known pharmaceutical preparations «Yantar-antitox» and «Yantarnaya kislota» (succinic acid). Dissolution of the composites based on kaolinite occurs gradually during 20 min and depends on activation time. The reasons of differences in the solubility of preparations are discussed.

The existing methods for measurement of Cu(II), Pb(II) and Cd(II) in whole blood need expensive complicated equipment, require preliminary destruction of the blood matrix, and generally cannot provide the necessary detection limit. We have reported the use of the stripping voltammetric method with modified thick-film electrodes for the analysis of whole blood and its fractions. The said electrodes, a quick potential sweep rate, and recording of differential voltammograms excluded extremely toxic mercury and its soluble salts from analysis, made the operations of the solution deaeration and chemical and electrochemical sample pretreatment unnecessary, and allowed decreasing the volume of test samples to 25

The films based on the oxides of zirconium (IV), hafnium (IV) and tin (IV) were obtained from the film-forming solutions of complex compounds of these metals with acetylacetone. Their properties are investigated. Optimal obtaining conditions were established using the results of thermal and X-ray phase analysis.

Mechanical treatment of brown coal in a centrifugal planetary mill causes partial destruction of cross-linking in the organic mass, mainly oxygen-containing groups. As a result, substantial changes occur in the molecular structure, the amount of graphite-like phase decreases, a sharp increase in the flexibility of macromolecular chains is observed, the rate of penetration of the THF molecules into the organic matter, its swelling ability and the yield of soluble substances. Transport of THF molecules in mechanically treated coal occurs mainly due to relaxation vibrations of the macromolecular chains.

A simple method of discrimination for the molecules of humic acids (HA) with respect to their dispersion states is proposed. The method is based on non-uniformity of the contour of HA luminescence spectra and involves the determination dependence of the position of maximum in the fluorescence spectrum _obs on the wavelength in the maximum of fluorescence excitation spectrum or determination of the dependence of on_obs. The applicability of the method is demonstrated with several samples of aqueous solutions of HA.

Mechanochemical treatment of quartz and its mixtures with ash-slag and iron oxides in the presence of various modifying additives (alcohols, activated carbon, polystyrene) was carried out. The dependence of specific surface, density and specific pore volume of quartz-containing mixtures on the time of treatment and a kind of modifying additive was investigated. Quartz and mixtures based on it exhibit ferromagnetic properties and are distinguished by good sorption ability toward organic substances. The synthesized sorbents were used to collect petroleum spill over water; high water purification degree (up to 98 %) was achieved.

A technology of electrochemical oxidation of bromide and chloride ions present in the brines of calcium chloride type involving an electrolyzer without a diaphragm is proposed. This technology allows one to obtain active chlorine from the initial raw material and to exclude transportation of liquid chlorine to consumption sites. It is proposed to use an excess of chlorine formed during electrolysis to oxidize bromide ions in the fresh portions of brine.

The analysis of the solution of the differential equation for a porous electrode operating in the intrakinetic mode under exponential kinetics is carried out. The distribution of polarization and thickness of the reaction region in porous water-proofed electrodes of different thickness operating under the same conditions is considered. A more accurate formulation of the intermediate-thickness electrode is presented; its specific features in comparison with a thick and a thin electrode are analyzed.