Home – Home – Jornals – Avtometriya 2012 number 5

The origin of gold and silver deposits in the Southern Kamchatka ore district is considered in terms of a quantitative model of the dynamics of volcanogenic orthomagmatic fluid systems (VOFSs). This model takes into account structural, fluid dynamic, and thermophysical features of phase evolution in hydrothermal fluid systems differing in geometry and structural conditions of the discharge on the surfaces of volcanic edifices. It is shown that VOFSs forming sulfide-rich gold and silver deposits have no stationary impermeable caps in their discharge areas. Rather, for the most part, narrow regions of junction of phase fronts form in their interiors and migrate to the surface of volcanic edifices.
Three geothermal system types are predicted by the example of plane and conical fluid conductance zones with a cap horizon: (I) where the shallow decompression boiling zone does not arise at all because of large lateral heat loss, (II) where subsurface decompression boiling zones appear at the beginning of the heat wave formation and then such a zone is practically confined to the cap rocks, and (III) where a quasi-stationary decompression boiling zone forms after an initial instability period or approach to a thermal equilibrium. Fluctuations or oscillations of decompression boiling zone fronts within a range of depths can exist in type III systems.

The microstructure and magnetic properties of accessory Fe-Cr-spinels from the Kytlym massif of the Urals platinum-bearing belt were studied. Atypical Fe-Cr-spinels in the form of magnetic microareas in grains of primary nonmagnetic Fe-Cr-spinel have been revealed for the first time in the bed dunites of the Kytlym multiphase concentrically zoned massif, North Urals. These spinels are responsible for the magnetic properties of the dunites.
It has been established that the microareas are separations in solid solution Fe²⁺ (Cr_{2- x} Fe_x ³⁺)O₄, which are enriched in Fe³⁺ and are probably an intermediate product of the transformation of primary accessory Fe-Cr-spinel during the formation of the dunite massif. These are magnetic microphases with a particular chemical composition, cation distribution, and corresponding reversed crystal lattice, which determine the main magnetic properties of the microarea: the magnitude and direction of magnetization vector and Curie temperature.
The formation of this earlier unknown type of magnetic Fe-Cr-spinel is probably conjugate with the formation and concentration of PGE mineralization in the bed dunites of the Kytlym platinum-bearing massif.
The presence of such magnetization carriers in rocks and ores must be taken into account in geophysical research at the Urals chromite and platinum-chromite deposits.

The zoning of massive orebodies at Cu-Ni sulfide deposits such as Noril'sk is commonly explained by fractional crystallization of sulfide magmatic melt. On the theoretical description of fractionation of its components, the results of mineralogical studies of orebodies are usually interpreted using the Rayleigh equation or its modification. But this equation is not applicable to describe crystallization of multicomponent melt and cocrystallization of several phases. In this work we present strict equations describing the distribution of components in a directly crystallized sample.
We analyzed the influence of phase reactions on the successive formation of phases during crystallization and on the formation of primary zoning in the sample. This approach permits one to compute the component distribution curves and the crystallization paths by the quantitative phase diagram model. An experimental study of fractionation in the systems Fe-Ni-S and Cu-Fe-S was carried out. They can be regarded as systems modeling formation of Ni- or Cu-rich sulfide ores. Such studies also yield qualitative and quantitative information about the phase diagrams of geochemical systems.
We demonstrated that directed crystallization can be applied to determine the equations of phase reactions and the dependence of partition coefficients on the melt composition and to construct the paths of crystallization and evolution of the tie-line position during one-phase and cotectic crystallization. By the example of the system Fe-Ni-S, all possible types of sample zoning after fractional crystallization are shown.
The main regularities of fractionation have been formulated, which are also applicable to multicomponent systems, e.g., Cu-Fe-Ni-S, which is widely used on the modeling of formation of zonal Cu-Ni sulfide ores.

The lower Katun' area has a complex neotectonic framework, with the largest fault zone of Katun' consisting of several en-echelon graben segments. Late Pleistocene sediments that fill the Katun' Fault bear signature of earthquake-induced soft-sediment deformation (seismites). Deformation due to seismic triggers can be discriminated from nonseismic one on the basis of special features and be related to prehistoric earthquakes according to a number of criteria. The observed deformation inside and outside burial mounds of the Chultukov Log-1 group may result from an earthquake that occurred at the end of the first millennium BC. Fault scarps in Late Pleistocene sediments, as well as deformed Iron Age tomb patterns, indicate that the Katun' lower reaches can have experienced past earthquakes of intensity at least 5 or 6 and magnitudes from 4.5 to 6.0.

The paper presents magnetobiostratigraphic data on the Cretaceous sediments stripped by well 8 in the southern side of the Om' basin within the Om'-Lar'yak facies zone (southern West Siberia). The biostratigraphical data show that the sediments under study formed in the Albian-Maastrichtian. The component analysis of natural remanent magnetization, based on thermal demagnetization and demagnetization with an alternating magnetic field, revealed the characteristic magnetization component. This confirms the paleomagnetic data used to compile the Cretaceous paleomagnetic section of the well. A paleomagnetic description was obtained, and a magnetobiostratigraphic key section of the Cretaceous sediments of the well was compiled on the basis of comprehensive data. It comprises five Upper Cretaceous regional horizons and same-named formations (Pokur, Kuznetsovo, Ipatovo, Slavgorod, Gan'kino), which have not been studied paleomagnetically at all in West Siberia. The magnetobiostratigraphic section comprises Albian-Maastrichtian stratigraphic units (43.5 Myr) and consists of three magnetozones. For example, the Pokur, Kuznetsovo, and Ipatovo Formations (total thickness 210 m), which show normal polarity with small reversed-magnetization horizons, form one long normal-polarity zone, N (al-st). The Slavgorod and Gan'kino Formations (total thickness 75 m), separated by a sedimentation gap, form two reversed-polarity magnetozones, R ₁ (km) and R ₂ (mt).
Reference datums (paleontologically well-constrained magnetozones) were used to correlate the magnetobiostratigraphic section with the common magnetostratigraphic and magnetochronological scales. The long normal-polarity magnetozone N (al-st), spanning the Albian, Cenomanian, Turonian, Coniacian, and Santonian, matches the Dzhalal hyperzone and chron C34 (~112-83.6 Ma). The reversed-polarity zones, spanning most of the Campanian ( R ₁ (km) (Slavgorod Formation) and Maastrichtian R ₂ (mt) (Gan'kino Formation)), match chrons C33(r) and C31(r) in the absolute chronology (~83.6-80 and 71-68.5 Ma, respectively) with a gap two chrons long (C33(n) and C32).

The Gunzhin Fault is a tectonic structure in the southern Hentiyn arched uplift (central Mongolia). A fragment of this fault, exposed by two paleoearthquakes, is traced northeastward for ~25 km from the northern periphery of Ulaanbaatar. The first comprehensive seismogeological studies here were aimed at determining the seismic potential of seismogenic structures on the basis of the dislocation parameters. Judging by the strain amplitudes and length, earthquakes with a magnitude of >7.0 might be generated here. The paleoearthquake was dated by the radiocarbon method at 7800-4667 B.C. Seismogenic zones with a high seismic potential were identified in central Mongolia for the first time. Dextral strike-slip faults were observed here among active NE-trending faults, suggesting the presence of E-W compressive stress.

The potential field data are considered the main supporting factor in the geophysical exploration process for detecting and evaluating the subsurface structures. In this respect a detailed land magnetic survey was performed in the area that was subjected before to seismic investigations. The main target of this study is to detect the deeper subsurface structures and to investigate possible relations of these structures with earthquake activity.
The RTP aeromagnetic map was used for detecting the regional extension of the interpreted structures from the land magnetic survey. The interpretations were performed by RTP land and aeromagnetic maps using filtering technique, least-squares separations, tectonic trend analysis, spectral analysis, Werner method, and Euler and two-dimensional techniques. The results show that the main dominant tectonic trends are 35?N- 45?W, 45?N-65?E, E-W, and Aqaba trends.
Moreover, two seismic lines WQ85-31B and 127 were interpreted, and the location of these lines was matched with the deduced tectonic map. The results show that there is a great matching between the location of the faults deduced from both the geomagnetic and seismic data. The obtained results show a complete agreement with the well logging data.
Furthermore, these structures are correlated with the recorded earthquake activities by National Egyptian Seismological Network (ENSN). The correlation implies that the studied area is more stable than other adjacent areas in the northern parts of Egypt close to the Mediterranean Sea and Nile River delta.

The main natural and human-induced radiation factors were assessed on the basis of long-term targeted radioecological studies in the Central Ecological Zone of the Baikal Natural Territory as a world heritage site. We identified areas with a problematic level of different radiation parameters determining the current radiation environment. Such areas should be taken into account in the development and implementation of nature management plans in the Baikal region, including ecotourism.

Synthesis of the available stratigraphic data on the Baikal basin sediments exposed around the lake and their correlation with offshore lake sediments and with onshore sections in the Baikal Foredeep allows a new perspective of the Baikal rift history. The basin sediments on the Baikal shore comprise three tectonic-lithologic-stratigraphic complexes (TLSC), which correspond to three seismic stratigraphic sequences (SSS) in the lake sediments and to three complexes in the Baikal Foredeep.
The oldest unit, TLSC-1, has a particular lithology being deposited in an environment which never repeated in the later history of the area. This proves the validity of its lithostratigraphic correlation with Masstraichtian-Early Oligocene sediments of the Baikal Foredeep constrained by biostratigraphy. Further support comes from isotope dating, paleontology, and other evidence.
Unlike seismostratigraphy-derived models, SSS-1 is correlated in the new model with TLSC-1 rather than with the Tankhoi Formation (which actually represents TLSC-2), and the onset of rifting is placed at the Late Cretaceous-Paleogene rather than the Oligocene (or Miocene). Thus, the Baikal rifting began prior to the India-Eurasia collision, and the first rifting pulse originally had other causes. This inference agrees with fission-track apatite thermochronology indicating Cretaceous ages of samples from the Barguzin rift basin on the northeastern flank of the rift system.
Rifting was developed successively in three different tectonic settings and was driven by different geodynamic mechanisms at each stage. First it was a passive response to Late Cretaceous-Eocene distributed continent-wide extension in Asia (purely passive rifting). At the second stage spanning Late Oligocene-Early/Late Pliocene time, the area was subject to compressive impact from the India-Eurasia collision, which propagated from the southwest since the Eocene and reached the region about 30 Ma to take control over its geodynamics (conventionally passive "impactogenic" rifting). Finally, the Pliocene-Quaternary evolution has been driven by extension from a local source associated with hot mantle material rising to the base of the rifted crust (active rifting).
The major rifting stages are further subdivided into substages: two substages in the second stage with the boundary at ~10 Ma (Middle-Late Miocene) and three substages in the third stage, with boundaries at 1.0-0.8 and 0.15-0.12 Ma. The stages and substages of rifting are separated by events of tectonic activity and stress reversal when additional compression produced folds and shear structures. The events that mark the stage boundaries show up as gaps, unconformities, and deformation features in the deposition patterns.
Thus, the three units of synrift sediments composed of eluvium, early molasse, and late molasse, respectively, were deposited during preorogenic, early orogenic, and postorogenic stages of rifting driven by passive (first purely passive and then "impactogenic") and active mechanisms.
The new model of the Baikal rift history agrees with data obtained by different other methods.

The problem of the Late Meso-Cenozoic tectonics and geodynamics of the southern framing of the Siberian Platform is discussed. This area abounds in Late Meso-Cenozoic structures composed of sedimentary deposits. Analysis of voluminous geologo-stratigraphic, geophysical, and geochronological (track dating) data showed that these structures, including the Baikal Rift Zone, resulted fr om the far-range impact of two collisions related to the prolonged convergence of the North China and Indian continents with Eurasia, which took place in the Late Jurassic-Paleocene and Cenozoic, respectively. The synchronous occurrence of two great tectonic events led to the formation of a complex structure and a sedimentary basin, which are of different geodynamic nature and cannot be united into the same sequence of Late Cretaceous-Cenozoic formation of the Baikal Rift Zone.
The Baikal system of shears and conjugate rifts formed in the Pliocene-Quaternary as a result of the far-range impact of the Indo-Eurasian collision. The latter led to the accumulation of the upper layered undeformed seismostratigraphic complex in all three Baikal basins. The sediments in Central Baikal are up to 3 km thick, and in the Selenga River valley they reach 5-6 km in thickness. The active intracontinental rift structures are characterized by zonal sedimentation. The middle layered deformed seismostratigraphic complex 1-1.5 km thick is recognized in all three Baikal basins and is similar to the Upper Oligocene-Lower Pliocene sediments of lacustrine-littoral, deltaic, and lacustrine facies widespread throughout the Baikal and Altai-Sayan regions and in Mongolia, wh ere they formed in the environments of large lake systems. As a result of the deformations caused by the Indo-Eurasian collision, the Upper Oligocene-Lower Pliocene sediments were involved in the Pliocene-Quaternary ramp and inilateral-ramp structures in intermontane basins of the Altai-Sayan region and in Mongolia. The lower seismically transparent seismostratigraphic complex occurs only in South Baikal and Central Baikal. It is 1 km thick in the east and up to 4-5 km thick in the west. The complex is a fragment of the Late Cretaceous-Paleogene lacustrine-river sediments of the large fore-Baikal piedmont basin, which formed at the final stage of evolution of the vast Mongolo-Okhotsk orogen.

The piecewise continuous (relay) nature of lumped control actions in problems of timeand energy-optimal control of a wide range of distributed-parameter nonlinear objects of engineering thermophysics is established. On this basis, the required programmed controls in a number of practical situations can be found by the proposed algorithmically precise (alternance) method. As an example, which is of independent interest, the problem of optimal control of nonlinear models of induction heating of metal semi-products before subsequent pressure treatment is considered.

The synthesis of automatic extremum seeking systems for a one-channel object whose model can be represented as a series connection of a nonlinear dynamic component and a static quality function with a distinct minimum or maximum is considered. The possibility of extremum seeking by the localization method involving the use of the highest derivative of the output variable of the dynamic part of the object in the feedback is discussed. Depending on the version of implementation of such feedbacks, two main types of extremal systems are distinguished: one-loop systems, in which data on the static characteristic gradient is sent to the controller, and two-loop systems. In the latter systems, it is suggested to use controllers based on the localization method for preliminary stabilization of processes in the internal loop containing the dynamic part. In the external loop, an integral control law is used and motion to the extremum with specified dynamic quality is implemented taking into account the data on the gradient. Modeling shows the features of the extremal systems under consideration.

A method for calculating the parameters of controllers for nonlinear nonstationary dynamic systems is proposed. The structure of the controller is a generalization of the structure of proportional-integral and proportional-integral-differential controllers. The method is applicable to unstable nonlinear systems with incomplete information on the plant model. The method is based on the deliberate formation of different-rate processes in a control system in which the stability of fast processes is provided by choosing the controller parameters, and the slow processes formed correspond to the reference model of the desired behavior of a nonlinear system. An example of the results of numerical simulation is given

The problem of control of an autonomous unmanned aerial vehicle with vertical takeoff and landing, which moves over a trajectory specified in the coordinate space, is considered. A method of constructing a system of automatic control of quadrotor vehicle takeoff and flight is proposed. Analytical relations for control actions on four engines that ensure vehicle motion over a prescribed trajectory with desired values of altitude and velocity are derived.

Dynаmics of the bacterial plankton community of an eutrophic water reservoir was studied by means of PCR-DGGE in laboratory microecosystems with the addition of amino acid lysine. The data obtained confirm the hypothesis of the narrow specialization of bacterial plankton species to the consumption of separate organic substances..

The study of phytoplankton from rivers and lakes in the southeast part of the West Siberian Plain and the eastern macrosclope of the Polar Ural with the help of scanning electron microscopy has revealed 25 taxa of Bacillariophyta from the class Centrophyceae (Aulacoseira - 7, Cyclostephanos - 1, Cyclotella - 4, Discostella - 2, Melosira - 1, Puncticulata - 1, Stephanodiscus - 7, Thalassiosira - 2), including new species for the flora of the investigated waterbodies. The revision of the species composition of Centrophyceae in waterbodies and watercourses in the southeast part of the West Siberian Plain has allowed more exact identifying the taxonomic spectrum of this class. At present the list includes 55 species, varieties and forms. During the first studies conducted in rivers and lakes of the Lyapin River basin (Polar Ural) 16 species of centric diatoms belonging to the genera Aulacoseira, Cyclostephanos, Cyclotella, Discostella, Puncticulata, Stephanodiscus have been recorded.

Investigation of the number of species and ecology of diatoms of modern bottom sediments in water bodies of the arctic polygon tundra in three sub-regions of Northern Yakutia was carried out. As a result, 161 taxons of diatoms were determined; the determinant role of depth, electroconductivity, pH of the medium, and geographic latitude in their distribution was confirmed, two complexes of species with respect to the leading abiotic factors were distinguished. The diatoms of the first complex prefer shallow water bodies of high latitudes with neutral and slightly alkaline water, and relatively high electroconductivity. The second complex is confined to the water bodies of lower latitudes with small electroconductivity, neutral and slightly acidic water.

Distribution of stomatocysts of chrysophyte algae in the plankton of water bodies of different types in the basin of the middle reach of the Irtysh (at the Omsk Region), as well as in the plankton and in fouling of a deep-water oligotrophic lake Teletskoe (Mountainous Altay) is considered. Classification of the morphotypes of stomatocysts is carried out. The number of morphotypes found in plankton samples from water bodies of the middle Irtysh basin is 30, in Lake Teletskoe - 60. Four similar morphotypes of cysts were revealed for the water bodies under investigation.

The distribution of resting stages of the blue-green algae (akinetes) in the bottom sediments of the littoral of a small Siberian water reservoir is studied. The irregularity (mosaicism) of the distribution of akinetes in the bottom sediments of the littoral is demonstrated, and the possible mechanisms of its formation are anаlyzed.

Concentrations of carotenoids buried in the bottom sediments of Lake Shira (Siberia, Khakasiya) were analyzed over the time interval of the last 2300 years. Carotenoids that are molecular markers of the corresponding groups of phototrophic organisms were detected in the bottom sediments. It was shown that the bottom sediments of Lake Shira are a promising object for climatic reconstructions of late Holocene in Southern Siberia.

Nonsynchronous vertical migrations of copepods Arctodiaptomus salinus were studied in two stratified lakes in the south of Siberia using the method of two-sectional assigned volumes. It was discovered that the presence of pronounced thermocline and the depth maximum of phytoplankton (Lake Shira) promotes intense individual migrations of zooplankton between the zones of epi- and hypolimnion.

Data set obtained in 19 experiments aimed at the studies of the growth of Daphnia of longispina group at the natural seston of the Buigach water reservoir (Krasnoyarsk) was used to analyze the connection of the parameters of somatic and generative growth of animals with the amount and quality of food. Depending on the quality of seston, two models of the development of Daphnia were distinguished. It was demonstrated that in spite of the existing positive correlation between somatic and generative growth, a noticeable fraction of the variations of the specific rate of generative production is determined by external factors of the environment - the relative content of N and -linolenic acid (N : C and ALA : C) in the seston.

Nutrition spectra of dreissenid populations Dreissena polymorpha и Dreissena bugensis inhabiting the Volzhsky reach of the Rybinskoe water reservoir and differing in the perennial dynamics of abundance were studied on the basis of biochemical markers. The features of the nutrition spectra of dreissenids are considered as a possible reason of changes in the abundance of the mollusks.

As a result of integrated studies carried out at the end of August - September 2008-2010, the ichthyofauna and food reserve for fish in Lake Oiskoe (the Ergaky Range) was investigated. The trophic status of the lake was estimated on the basis of the biomass of phyto-, zooplankton and zoobenthos. Relying on calculations of average biomass and production per season for zooplankton and zoobenthos, estimations of potential ichthyomass, fish production and possible fishing amount were estimated.

Results of the mineralogical and geochemical investigation of technogenic aerosol samples collected in 2011 in the northeastern direction from Novosibirsk in the plume of the Novosibirsk Chemical Concentrates Plant JSC, as well as aerosol collected near the Novosibirsk Tin Plant JSC and Heat and Electric Power Plant No. 3 are reported for the first time. Uranium content and its mineral formations were determined by means of ICP-MS, ICP-AES and scanning electron microscopy.

Ground water in the region of slurry dumps of low-activity wastes from the Angarsk Electrolysis Chemical Combine manufacturing enriched uranium was studied. It was established that the E_h values vary from weakly reductive to oxidative, pH varies from neutral to alkaline values. The presence of a hydrodynamic mound in the region of the slurry field provides vigorous diffluence of the technogenic infiltration runoff, which results in possible local increase in the concentrations of , and in the zone of the hydrodynamic mound above the maximum permissible level. Alkaline sodium nitrate solutions are characterized by higher salt content (up to 9 g/L) but uranium content of all the ground water samples (background, in the region of the stores of solid and liquid radioactive wastes) is below the MPC level. The composition of phases that are able to precipitate from the disposed slurry water after neutralization with Са(ОН)₂ and settling was confirmed with the help of thermodynamic calculations. Possible increase in the concentration of uranium in the interaction of calcium urinates with CO₂ (solution) was demonstrated. Limiting concentrations of uranium in solutions were calculated; the limiting values are determined by the s9lubility of uranium-containing minerals formed depending on pH, partial pressure of СО₂ and the presence of cations (Ca, Si, Al).

Results are presented for hydrogeochemical monitoring the industrial area of the JSC “Novosibirsk Chemical Concentrates Plant” as well as experimental data concerning the demercurization of soils and building materials those were contaminated with mercury. A comprehensive approach to the demercurization and geological conservation of mercury-containing waste is proposed that includes three stages: 1) a centrifugal extraction of mercury from solid wastes including contaminated grounds, soils and building refuse; 2) chemical immobilizing the mercury remaining in the insoluble form (naturally occurring mineral Stchuettite); 3) geological conservation.

Dependence of the properties of calcium phosphate compounds on the method of their isolation from biological raw material was studied. Physicochemical studies of the properties of resulting materials were carried out. The proposed procedure allows one to obtain ultrafine powders of biological hydroxyapatite with controllable particle size and composition maximally approaching the composition of bone tissue. It was established that the calcium phosphate compound deposited from the solution that was obtained by demineralization with the solution containing hydrogen chloride 1 mol/L is most close to the mineral matrix of bone tissue.

Physicochemical properties inherent in chitosan-containing solutions as well as the sorption properties of carbon materials modified with chitosan were studied. It has been found that the composites obtained exhibit anion-exchange properties. The chitosan-containing materials have been shown to exhibit a sufficiently high sorption capacity, which makes them efficient as sorbents for the concentration and extraction of gold, and other heavy and radioactive metals in the future.

Cerium sulphate ion-exchange sorption by containing naturally occurring clinoptilolite tuff from aqueous solutions was studied within a wide range of concentration values (10^-5-10^-2mol/l). Adsorption isotherms and kinetic parameters have been determined.

An effect of different methods for aspen wood activation (grinding in the mills of different types, explosive autohydrolysis, catalytic oxidation by hydrogen peroxide and the combination of these methods) exerted on the structure, chemical composition and reactivity of activated wood was studied. It has been found that all the methods of aspen wood mechanical pretreatment result in changing the supramolecular structure, chemical composition and reactivity thereof: activated samples exhibit increasing the content of readily hydrolysable polysaccharides, with reducing the concentration of polysaccharides difficult to hydrolyze and of residual lignin, as well as with increasing the rate of polysaccharide acidic hydrolysis into monosaccharides and the rate of lignin oxidation by hydrogen peroxide.

Phase formation was studied for the systems of Cyanex 301 (bis(2,4,4-trimethylpentyl)dithiophosphinic acid)–organic solvent (toluene, heptane, octane)–sodium hydroxide–water–trioctylamine. It is demonstrated that the Cyanex 301 transition into a salt form (three-phase extraction) results in achieving the separation of the organic extraction agent solution into the solvent phase and a cation-exchange extraction agent. The sodium salt of Cyanex 301 is almost completely transformed into a new aqueous micellar solution. Conditions have been determined for the efficient separation of the organic phase components and for the isolation concentrated Cyanex 301. An effect of trioctylamine additives exerted on nickel extraction in the systems with Cyanex 301 was studied. A scheme has been proposed for the extraction of nickel using a three-phase extraction, wherein nickel is extracted by means of the concentrated solution of Cyanex 301 from acidic solutions resulted from leaching the ore, the extract is mixed with an organic amine solution to be re-extracted with sulphuric acid, whereas the organic phase is separated into initial components via treatment by sodium hydroxide solutions.

The interaction of bismuth (III) citrate BiC₆H₅O₇ with the aqueous solutions of potassium hydroxide in different concentrations was studied by means of X-ray phase analysis, IR spectroscopy, thermogravimetry and chemical analysis. The conditions for the formation of the potassium salt of bismuth (III) citrate having the composition KBiC₆H₄O₇ · H₂O were determined. Reasonability of obtaining this compound through the interaction of the aqueous solution of potassium hydroxide with bismuth (III) citrate with their molar and mass ratio equal to 1.0 was shown.

Modifying the low-calorific lignite from the Sergeevo deposit by means of liquid-phase catalytic alkylation with isopropyl alcohol was performed. The basic processes involved in the interaction of the coal under investigation with isopropyl alcohol were described. A positive effect of the alkylation treatment exerted on the coal bituminosity, the componential composition and the physicochemical characteristics of modified products obtained has been revealed.

Via the reaction of alkaloid cytisine, l-ephedrine, d-pseudoephedrine as well as glucosylbenzylamine and xylosylbenzylamine aminoglycosides with vinyloxyethylisothiocyanate and its acetal derivatives, we synthesized and characterized novel 2-vinyl-, N-1-propargyl-, 1-N-phenyloxyethoxyethylo-N’-aminothiourea species. By the example of the N-vinylethoxythiocarbamoyl derivatives of l-ephedrine and d-pseudoephedrine is demonstrated that the mentioned thiourea species could quite readily undergo hydrolyzing in the presence of acids. On the basis of salicylic acid hydrazide we have synthesized and studied the acidic hydrolysis of corresponding vinyloxyethylthiosemicarbazide. The composition and the structure of the thiourea derivatives synthesized were confirmed by IR spectroscopy, ¹H NMR, ¹³C NMR and mass spectrometry as well as by XRD structural analysis.

Results of the comparative analysis of the effect of oxidative modifying performed using ozone, nitrogen (I) oxide and low-temperature oxygen plasma, on the chemical composition of coal from the Khushuut deposit (Mongolia) and its ability to thermal destruction are reported.

The content of acetate ions in the blood of patients after cardiac surgery in the course of hemodialysis using different dialyzing solutions was investigated for the first time. Using the method of capillary electrophoresis it was revealed that in the case when the bicarbonate dialysate contains acetate ions in a small amount (3 mmol/L), the concentration thereof in blood exhibits a 12-fold increase, which causes enhancing the risk of cardiovascular instability in  the course of hemodialysis.

Studies were performed concerning the seasonal dynamics of major ions (Na⁺, Mg²⁺, K⁺, Ca²⁺, SO₄^2-, Cl^-, HCO₃^-), Si, 52 trace elements, organic carbon, pH, O₂ in the Selenga River, the main tributary of Lake Baikal and the rivers flowing into the Selenga in the Russian territory, the flow paths and lakes of the delta within the barrier area of Lake Baikal (up to 7 km from the mouth of the Selenga River). Using the factor analysis we revealed four main groups, those differ from each other in the spatial and temporal distribution of the components in the Selenga River. The first group comprises the water salinity, the major ions and trace elements, some conservative trace elements (B, Br, Sr, Mo, Ba, Re, U). The concentration values for these components are maximal within the ice period (March) and minimal within the flood period (May), exhibit an increase on the frontier with Mongolia reducing towards the mouth as being diluted by less saline water of the tributaries of the Selenga River. The elements of the second group are connected with the content of dissolved organic matter capable of mobilizing difficultly soluble and almost insoluble elements (Be, Al, Ti, Fe, Ni, Cu, Ga, Y, Zr, Nb, Hf, REE, Pb, Th) to produce fine-dispersed organomineral complexes. The concentration values for these elements demonstrate increasing in the spring, in the course of the snowmelt and of an active removal of organic matter from the catchment area. The third group of the elements (Si, Li, Cr, Mn, Co, Zn, Ge, Rb, Ag, Cd, Sn, Cs, Bi) reflects the processes of water acidifying against the background of seasonal dynamics inherent in the dissolved oxygen. Concentration values for these elements increase towards the mouth (except for Co within the period of spring and autumn, as well as Ge in winter), being to a significant extent increased in the winter. The fourth group of the elements (V, As, Sb, I, W, Cu) represents a marker of a weak cross-border transfer in summer. Increased concentration values of these elements are observed in July, especially on the upper section of the river (0–120 km from the frontier with Mongolia). The maximum and average weighted concentrations of the most of trace elements in the Selenga River are lower than those inherent in the global natural river background. Exceeding the maximum background concentration values is observed for Mo (10 %), Mn (10 %) and Ge (60 %). Average weighted background concentration values exhibit a 2- to 5-fold exceeding in Zr (2.1), Nb (2.1), Sr (2.5), Ti (2.9), U (3.5), Y (3.5), Zn (3.7), Mo (3.8) and Sn (4.9), which could be caused by the geological structure of the basin and the naturally occurring processes of mobilizing the elements. The concentration of Mo, Mn, Cu, Al, Fe, V in the general river station of the Selenga River and the tributaries thereof in some seasons are slightly higher than Russian standards established for fish-industry water basins (in 80 % of cases less than 2 MPC). Within the barrier zone of Lake Baikal there is an excess over the fish industry water standards in Mo registered to be constant (1.2–2.1 MPC): for Cu in winter (up to 1.8 MPC), in summer (up to 1.9 MPC), in autumn (up to 1.3 MPC); for V in summer (up to 1.6 MPC); for Mn in winter (up to 2.2 MPC).

Chemical composition of the light fraction (Т_boil ≤ 300 °C) of heavy pyrolysis tar (HPT) was studied; more than 40 components were identified. The content and nature of the still bottoms of HPT were determined. It was established that the method of HPT processing is determined mainly by the concentrations of naphthalene, unsaturated compounds and still bottoms. The processes of HPT polymerization with the application of radical type initiators dicumyl peroxide and di-tert-butyl peroxide (DTBP) were studied. New grades of petroleum polymer resins (PPR) with high softening temperature were developed; they can be used in rubber-processing industry. A method of HPT processing using the still bottoms of styrene rectification and DTBP, followed by evaporation of volatile components, was proposed for obtaining PPR with required properties and the yield up to 68 %.

Effect of the mechanical activation of rice husk on the progress of subsequent enzymatic hydrolysis was studied. It was established that mechanical treatment promotes an increase in specific surface area, destruction of the silica shell coating lignocellulose, and substantial amorphization of the crystal regions of cellulose. As a result, the degree of conversion of polymer carbohydrates into soluble saccharides increases practically by a factor of 13. So, mechanoenzymatic treatment of rice husk allows one to obtain carbohydrate-containing intermediate product that may be used for further microbiological processing.