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A complex of medical and biological studies of the effect of 4-(hydroxyethyl)phenol ( p -tyrosol, aurol) on all life stages for the groups of different animals is considered. A substantial decrease in the level of mortality was revealed for each experimental group and at each life stage. The efficient action of aurol at the early life stages and during subsequent development of organisms was demonstrated. Aurol exhibits antioxidant properties, affects vascularization and neoangiogenesis and thus restores the nitroxidergic system of the brain, improves blood composition, strengthens the structures of the most essential systems of the organism, and decreases bird mortality at the early stage of life. The use of aurol in poultry breeding leads to early ovicell maturation in hen organisms, which causes an increase in egg-laying ability. In the cases of vaccination or diseases of birds, an increase in bird survival rate (90 %) is observed in the case of the treatment with known antibiotics in combination with aurol, compared to the reference group without aurol treatment (80 %). Neuroprotective action of aurol is exhibited as a sharp decrease in miscarriage rate during shearing pregnant goats. A positive effect of aurol application in cattle breeding causes the growth of more vigorous young individuals advancing in live weight by 5-7 % in comparison with the reference group. The long-term result of aurol action manifests itself in the animals of the experimental group during 25-30 days after injections and is explained by an increase in hemoglobin concentration and the high biological activity of blood serum. A substantial economic effect achieved during industrial tests of the maintenance of animals with the help of aurol at all stages of their life is the first example of an increase in productive longevity.

The decomposition of eudialyte concentrate was studied by means of sorption conversion in the 2 mass % solution of sulphuric acid. It was shown that eudialyte decomposes at a temperature of 80 ^оC with the formation of silica gel, while silica sol is formed at 20 ^оC. The efficiency of the sorption of refractory rare elements by the sorbent in the mode of silica sol formation increased in comparison with the mode of silica gel formation from 52.5 to 89.4 for zirconium, from 60.1 to 89. 2 for hafnium, from 7.4 to 85.1 for niobium, from 0 to 67.1 for tantalum, from 27.6 to 80 for titanium, respectively, with the provision of a high degree of extraction of rare earth elements (REE) - 82.9 %, including REE of yttrium and medium groups up to 86-89 %. The major part of the losses of niobium, tantalum, titanium and REE is determined by their inclusion in loparite and other accessory minerals that are untreatable under the studied conditions. It is assumed that a substantial increase in the sorption of rare elements of IV and V groups at 20 ^оC (in comparison with the results obtained at 80 ^оC) is due not only to the formation of silica sol but also to a decrease in the hydrolysis of the cations of these metals with the formation of their forms that are not sorbed by the sulphocationite. The features of decomposition of the eudialyte concentrate by the low-concentrated solutions of nitric and sulphuric acids were compared. The reasons providing the formation of silica sol during the low-temperature sulphuric decomposition of eudialyte are discussed. It is stressed that the studied method may be the basis of an efficient technology of eudialyte concentrate processing because the application of this method results in a decrease in acid consumption by a factor of 3-5 in comparison with traditional acid procedures. As a consequence, the amount of liquid wastes subjected to utilization is reduced, the effective specific radioactivity of the silica residue and the consumption of energy resources decrease.

The effect of temperature factor, polymer additives and magnetic field on the kinetics of sediment formation, pour point and microstructure of oil residue from high-paraffin low-resin oil is investigated for the purpose of developing the methods aimed at a decrease in the rate of formation of asphaltene sediments during oil transportation and storage. Independently of the temperature conditions of action, the introduction of additives into oil causes a decrease in the amount of the formed sediments. The maximal inhibiting capacity is that of DP2 additive causing a decrease in the amount of oil sediments almost by a factor of 9. The combined treatment of oil with magnetic field and the additive does not lead to an additional decrease in the amount of the formed oil residue and pour point.

Objective evaluation of the state of the environment may be made on the basis of the parameters of human health. The cities of Kirovsk, Apatity, and the Lovozersky district stand out among the cities and districts of the Murmansk Region for the diseases of the musculoskeletal system and urolithiasis. The population of these areas uses water formed within the giant alkaline massifs - Khibiny and Lovozero, containing the oxides of strontium, thorium, barium and rare earths. The solution - crystalline substance system was studied with the help of physicochemical modeling using the Selector software package. Environmental conditions and physiological parameters of the human organism were taken into account. Natural drinking water, gastric juice, a mixture of drinking waters and gastric juice were considered as the solution, while the newly formed phases in equilibrium with solution were considered as the crystalline substance. The chemical forms of the migration of elements including uranium were studied, and the conditions of mineral phase precipitation in the system natural waters - gastric juice under the conditions of reduced and increased acidity were investigated. It was demonstrated that the forms of element migration (Ni²⁺, Ba²⁺, Pb²⁺, Sr²⁺) remain carcinogenic or toxic at the temperature and parameters existing in the stomach. The proposed approach opens new opportunities in environmental and medical-ecological studies.

The composition and morphology of hydrolytic lignin obtained from sunflower husk are studied before and after alkaline modification. The sorption properties of hydrolytic lignin towards Cr(VI) ions were studied under static conditions (at the solid to liquid phase ratio 1 : 1200, and a temperature of 20 °C) from the aqueous solutions of potassium dichromate with different initial concentrations of Cr(VI) ions (0.05-1.0 mg/L). Sorption kinetics was studied, and the analysis of the integral kinetic curves of sorption was carried out in accordance with chemical kinetic models.

The reasons for the formation of nitrous oxide (a greenhouse gas with CO₂-equivalent equal to 310) at modern plants manufacturing weak nitric acid are analyzed. The amount of annual N₂O emission depending on the operating conditions of the ammonia converter and on the method of the removal of nitrogen oxides NO_х is estimated. A technological scheme of simultaneous low-temperature removal of NO_x and N₂O from exhaust tail gases is proposed, in which V/Al catalyst for the selective catalytic reduction (SCR) of NO_x with ammonia and Сs/Co₃O₄ catalyst for N₂O decomposition are used. Mathematical modeling of a 2-layer catalytic reactor is carried out; the charges of both SCR catalyst and N₂O decomposition catalyst are determined, which ensures compliance with environmental emission standards for all nitrogen oxides.

In solving the ecological problems caused by the contamination of the Arctic shelf with oil products, the application of satellite images is relevant. These images allow monitoring observations of the state of oil-producing territories and timely revelation and evaluation of the risks of oil pollution in hard-to-reach and fragile tundra and marine ecosystems. On the basis of remote and land-based imaging data, the zones under the risk of oil pollution were mapped over the territory of the Kolguyev island. The ecological state of soils and coastal waters of the island are considered. A technology for the purification of oil-polluted regions with the application of aboriginal psychrophilic microflora stimulated by nutritive mineral substrates is proposed.

Rhenium containing catalysts are prepared on the basis of high-silica zeolite of pentasil family with a silicate modulus 40. Modification of the zeolite with rhenium introduced using various methods results in the changes in its structural characteristics: a decrease in specific surface area, pore volume and diameter. The most noticeable decrease in these parameters is observed when impregnation and ion exchange are used. The use of rhenium-containing zeolite catalysts for upgrading the straight-run gasoline fraction of oil allows increasing the yield of liquid products - high-octane gasolines characterised by a low content of aromatic hydrocarbons and a high octane number. A decrease in the aromatizing activity of Re-containing catalysts contributes not only to improvements in the environmental characteristics of resulting gasolines but also into an increase in the time of the stable operation of catalysts. Due to an increase in the rate of hydrogenation, the introduction of rhenium significantly reduces the amount of coke deposits formed on the catalysts under study during the process. According to the rate of formation of coke deposits, Re/MFI catalysts prepared using different methods are ranked as follows: ion exchange < ultrafine powder < impregnation < mixing with salt < MFI. Carbon densification products formed on rhenium-containing catalysts are less condensed and more homogeneous than coke obtained on unmodified zeolites. According to the degree of decrease in catalytic activity or aromatizing ability during the same time of operation, the catalysts under study may be ranked as follows: MFI > Re/MFI (ion exchange) > Re/MFI (ultrafine powder) > Re/MFI (impregnation) > Re/MFI (mixing with salt).

The laws governing the conversion of components of natural and associated petroleum gases into aromatic hydrocarbons over zeolite catalysts modified with active metal additives are investigated. According to the data obtained, the catalysts under study exhibit high activity in the course of the aromatization of lower C2-C4 alkanes. For almost complete conversion of the feedstock, the selectivity towards the formation of aromatic hydrocarbons over Ga-AC and Zn-ZSM-5 samples at 550 °C is 44.6 and 37.8 %, respectively. The highest catalytic activity and selectivity in the conversion of natural gas into aromatic hydrocarbons is exhibited by Zn-containing zeolites. The yield of aromatic hydrocarbons over them reaches 26.7 % at 650 °C. This is higher by 9.0 and 19.0 % than the yield over Ga-containing and unmodified zeolites, respectively. The revealed differences in the behaviour of the catalysts are due to various functional features of their active sites formed when metals are introduced into the zeolite matrix. The yield of aromatic hydrocarbons from the conversion of a mixture of C2-C4 alkanes over zeolite-containing catalysts is significantly higher than that in the case of natural gas conversion, which is due to the high thermodynamic stability of its major component - methane. The nature of coke deposits formed on the surface of the catalysts under study during the aromatization of low-molecular C2-C4 paraffins was studied by means of differential thermal analysis. The stability of Zn-ZSM-5 in this process was determined to be higher than that of the Ga-containing zeolite.

The composition and structure of nitrogenous bases of the resins of bituminous oil from the Ashalchinskoye deposit of Tatarstan are investigated using a complex of analytical methods including elemental and functional analyses, determination of molecular masses, 1H NMR spectroscopy, structural group analysis, gas chromatography, and mass spectrometry. The nitrogen bases of the resins in oil are analysed before and after their thermal treatment at 450 °C for 30 min in the inert medium. It is established that the nitrogenous bases of the initial resins and "secondary" maltenes are represented by high and low molecular weight compounds. High molecular weight bases prevail in both cases, though their proportion in "secondary" maltenes is much lower. Thermally transformed bases are characterised by lower average molecular weights. This is due to the destruction of alkyl and naphthenic moieties proceeding in the course of thermolysis and resulting in the changes in their structure and the formation of lower molecular weight compounds. As revealed by means of structural group analysis, the mean molecules of a significant part of high molecular weight bases of the "secondary" maltenes are more aromatic due to a decrease in the number of naphthenic cycles and in the number of paraffin carbon atoms in their structural blocks. Low molecular weight bases differ from those of the initial resins in a higher number of naphthenic cycles in the structural blocks of their mean molecules. Alkyl-substituted quinolines and benzoquinolines, naphthoquinolines, naphtho[2,1,8-def]quinolines, thiophenoquinolines, and benzothiophenoquinolines have been identified among the major compounds of initial resins and "secondary" maltenes. The maximum in their distribution falls on alkylbenzoquinolines. The bases of "secondary" maltenes are characterized by a higher relative content of alkylquinolines and alkylthiophenoquinolines. A distinctive feature of the bases of "secondary" maltenes is also an increased proportion of structures with a lower number of carbon atoms in alkyl substituents.