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In the qualitative analysis of complex mixtures of unknown composition, a promising direction for increasing the reliability of the identification of substances is the joint use of several simultaneously determined analytical parameters. A combination of chromatographic methods with FTIR spectroscopy, mass spectrometry, or other methods is used. In solving complex analytical problems of industrial nature, it is economically expedient to use only chromatographic methods. In analyzing complex multicomponent mixtures with a high density of peaks in the chromatogram, the precision of the determination of retention time determines the reliability of the identification of substances and of the result of analysis, using identification both directly by the absolute retention time and by relative parameters derived from it (relative retention times, retention indices). The standard deviation of a measurement of the chromatographic retention time is a measure of precision. Experimental chromatographic retention times were obtained for analyzing a mixture by the following scheme: initial isotherm, temperature programming, final isotherm. A sharp increase (by one order of magnitude) in the numerical value of the standard deviation was noted at the step of temperature programming. A regression equation was obtained linking the point estimate of the standard deviation of the retention time and column temperature. The performance characteristic of the regression equation is obtained as a function that enables calculating the total standard uncertainty in the estimate of the standard deviation of the chromatographic retention time. The results can be used to refine chromatographic retention time and indices that ensure the reliable identification of substances.

A new approach has been proposed to the synthesis of optically active 4H-3,1-benzoxazine derivatives based on α-amino acids. The target products have been obtained by reaction of o-(cyclopent-1-en-1-yl)aniline with N-Boc-protected amino acids, followed by removal of the protecting group and heterocyclization by the action of dry hydrogen chloride in methylene chloride.

The conclusions about the nature of bed fluidization and the rate of polyfractional material entrainment in the cylindrical vortex chamber with the air supply through the lower and upper end swirlers were drawn, based on the visual observation of the fluidized bed, the determination of entrainment of the bed dispersed material by weighing the material after a given time of vortex chamber operation, and also by means of the numerical simulation of dynamics of the fluidized bed of particles.

The oxidation of N-acetyl-2-ethyl-2-methyl-2,3-dihydro-1H-indole with pyridinium chlorochromate, CrO3 · 2 Py, or CrO3 gave N-acetyl-2-ethyl-2-methyl-2,3-dihydro-1H-indol-3-one which was hydrolyzed to 2-ethyl-2-methyl-2,3-dihydro-1H-indol-3-one. The latter was reduced with sodium tetrahydridoborate in ethanol to 3-hydroxy derivative and converted to the corresponding oxime by treatment with hydroxylamine hydrochloride in methanol. Baeyer—Villiger oxidation of 2-ethyl-2-methyl-2,3-dihydro-1H-indol-3-one and Beckmann rearrangement of its oxime were studied.

The nitration, oxidative halogenation, and radical bromination and chlorination of 2-ethyl-2-methyl-2,3-dihydro-1H-indole afforded the corresponding nitro, amino, and halo derivatives. The synthesized compounds were evaluated for their antioxidant, antimicrobial, and plant growth regulating activities.

Data of field studies elucidate how the chemical composition of groundwaters is formed at urban territories in the southern Fore-Ural areas. These data were used to determine the changes in the salt composition of pore-waters in the clay rocks, their exchange–adsorption characteristics, and the distribution and accumulation of supertoxicants in the rocks and waters. The effect of the chemical composition of the waters on hazardous geological processes is estimated. It is determined that the geological environment is most strongly impacted within the depth range from the surface to 15–20 m. Dioxins and heavy metals are concentrated in the ground at the sites of industrial facilities near the surface (at depths up to 5–7 m), and their concentrations drastically decrease at depths from 5–7 to 20 m. Liquid organic contaminants and water-soluble salts penetrate through almost the whole circulation zone. The self-clarification of the aquifers and the recovery of the natural parameters takes dozens to hundreds of years, even after the contamination source is eliminated, i.e., the characteristic time of this process exceeds the lifetime of one generation of humans.

We studied a lean propane-butane-air mixture ascending through a round hole of 10-mm diameter, covered by a brass mesh as a single element of the multicellular flame. Gas temperature was measured by the CARS method (Coherent anti-Stokes Raman Scattering) with original software for spectra processing. The vertical and horizontal velocity components were measured by the PIV method (Particle Image Velocimetry). Distributions of heat release intensity and heat fluxes, which cannot be obtained in direct measurements, were estimated using balance relationships in the energy equation. The results were compared with the data obtained for the rich mixture flame in experiments with the same burner. Convective and molecular heat fluxes were considered separately. It was shown that when the rich air mixture with propane-butane burns, the heat flux caused by thermal conductivity reach a maximum at the center of the heat-release zone. Their intensity is substantially lower in comparison with the convective fluxes behind the flame front, which in turn are almost twice as weak as the convective flux in the flame of a lean mixture. The maximal intensities of heat release in the flame of a rich mixture are lower than in the lean one.

The effect solvents have on the processes of rearrangement and elimination in N-(1-methyl-2-butenyl)aniline (I) in the presence of HCl is studied. It is shown that the dependence of the rearrangement and elimination rate constants of (I) · HCl on the nature of solvents are described perfectly by the Koppel–Palm equation, which considers both nonspecific and specific solvation. The inhibitory effect of solvent nucleophilicity is explained by the complexation between (I) · HCl and solvent molecules. Analysis of the (I) · HCl conversion products obtained in a mixed solvent (m-toluidine + nitrobenzene) demonstrates the intermolecular transfer of the allyl moiety, confirming the formation of allyl cations in the Claisen amino rearrangement.

A new version has been proposed for the synthesis of analogs of the known herbicides mecoprop (MCPP) and dichlorprop (2,4-DP) by ozonolysis of chloro derivatives of (pent-3-en-2-yloxy)benzene.

Results of an experimental study of hydrodynamics and diffusion combustion of hydrocarbon jets are presented. Various regimes of instability development both in the jet flame proper and inside the source of the fuel jet are considered. The experiments are performed for the case of subsonic gas jet expansion into the air from a long tube 3.2 mm in diameter in the range of Reynolds numbers from 200 to 13 500. The fuel is the propane–butane mixture in experiments with a cold jet (without combustion) and pure propane or propane mixed with an inert dilutant (CO2 or He) for the jet flame. The mean velocity and velocity fluctuations in the near field of the jet without combustion are measured. Among four possible regimes of cold jet expansion (dissipative, laminar, transitional, and turbulent), three last regimes are investigated. The Hilbert visualization of the reacting flow is performed. The temperature profiles in the near field of the jet are measured by a Pt/Pt–Rh thermocouple. An attached laminar flame is observed in the transitional regime of propane jet expansion from the tube. In the case of combustion of C3H8 mixtures with CO2 or with He in the range of Reynolds numbers from 1900 to 3500, the transitional regime is detected in the lifted flame. Turbulent spots formed in the tube in the transitional regime exert a significant effect on the flame front position: they can either initiate a transition to a turbulent flame or lead to its laminarization.

Photographs and spectra of single-bubble sonoluminescence of a bubble moving in pure water and aqueous solutions of $${\text{Ru}}({\text{bpy}})_{3}^{{2 + }}$$ are obtained. It is shown for ruthenium complex solutions that there are luminescence regions outside the main trajectory of motion of the luminous bubble, which are absent in pure water. The observed spatial localization of these regions confirms that (as we have shown previously) they are caused by sonochemiluminescence of the ruthenium complex in the solution bulk that is secondary relative to the primary sonoluminescence of the bubble.

Selective methylation of aniline and its derivatives with dimethyl carbonate under the action of binder-free micro-, macro-, and mesoporous zeolites FeHY-mmm was performed to obtain N-monomethylanilines.

This paper describes the study of evaporation and combustion of ethanol under a horizontal wall in a stratified shear gas layer in the case of the Rayleigh–Taylor instability. Data on the nature of flow are obtained with the use of particle image velocimetry (PIV), and temperature profiles are recorded by a thermocouple. It is shown that cells are formed in a narrow range of air velocity of 0.6 ± 0.05 m/s and does not depend on the height of the obstacle (backward ledge or an edge is 0–7 mm in height). The flow between the wall and flame front is an alternation of mushroom-shaped structures moving from one wall to another. In the cellular flame, the flow of substance (with respect to the air flow) exceeds its level in a standard laminar boundary layer three times. The averaged transverse velocity is directed away from the wall in the boundary layer with combustion without cells, and it is reduced and directed toward the wall in the cellular flame between the wall and flame front.

The ion-exchange properties of terrigenous rocks have been studied, and physicochemical modeling has been used to study the formation of sulfate sodium water in the Volga–Ural Basin of the Russian Plate and the Kartalinskii Basin of the Caucasian hydrogeological folded area. Hydrogeochemical experiments have shown that the exchange-adsorption interaction between gypsum water and adsorbed Na+ of terrigenous rocks in the water–rock system involves many stages, resulting in the accumulation in solution of considerable amounts of Na2SO4 (up to 9–17 g/dm3).

Soluble electron-donor conducting (co)polymers based on functionalized monomeric anilines have been synthesized and characterized for the first time. It has been shown that there is a good correlation between the results obtained from investigations of the electrochemical properties of polyaniline derivatives by the methods of cyclic voltammetry and on the basis of the temperature dependence of the electrical conductance. The polymer based on 2-(1-methyl-2-buten-1-yl)aniline has the lowest energy level of the highest occupied molecular orbital, which determines the prospects for its use as a donor in the active layer when designing organic solar cells.

The Particle Image Velocimetry (PIV) technique and laser Doppler anemometer (LDA) were used to measure the components of tangential and axial velocities of gas and particles in a vortex chamber with a fluidized bed, particle layer dynamics was estimated qualitatively, and the flow in the vortex chamber with a centrifugal fluidized bed of solid particles was simulated numerically. It is shown that with the growth of gas velocity in the swirler slots, the rotation velocity of bed grows almost linearly, and with an increasing bed mass, the rotation velocity decreases. Data on distributions of the volume fraction of particles and gas flow velocity inside the bed were obtained by numerical calculation.

Chemiluminsecence in the visible spectral region is detected for the first time during oxidation of aniline by an ozone–oxygen mixture in aqueous solutions of hydrochloric acid. The kinetics of changes in the luminescence intensity in the temperature range of 284–327 K is investigated and the activation parameters of the process are determined.

Nuclear protein extract is an important substance for studying different molecular systems of the cell, particularly transcription machinery. The paper briefly describes extraction methods and provides a protocol for the preparation of extract from nuclei of Drosophila embryos using salt extraction. The extraction efficiency of transcription factors and chromatin proteins has been checked under different salt concentrations. The paper also provides data about chromatographic properties of some protein factors regulating gene activity.

The Southern Urals exemplifies hydrogeochemical environments at mining districts. Information obtained by studying the geochemistry of nonferrous-metal industrial wastes (both mine and dump drainage) is important not only because these wastes are potential sources of base metals but also in the context of geoecological problems. The Southern Urals is one of Russia’s principal producers of Cu and Zn concentrates for metallurgical processing: the region produces 12–15% Cu and 49% Zn concentrates in the country and 35% Cu and 69% Zn concentrates in the Urals. The Yubileinoe, Podol’skoe, Sibai, Uchaly, Novy Uchaly, and Gai deposits are the largest in the Urals. The ores of these deposits contain certain components (Se, Te, Cd, Co, Ga, Ge, In, Be, etc.) that are environmental contaminants. The volume of mine and dump drainage in the Southern Urals amounts to 9 million m3/year, and its mineralization varies from 3.0 to 30–40 g/L, occasionally as high as 365 g/L, with a sulfate, chloride–sulfate calcic–magnesian, magnesian–sodic, and magnesian–calcic composition of the waters. The minor and trace elements of the regional waste waters whose concentrations exceed the regional background values are Cu, Zn (one to four orders of magnitude), As, Cd (one to three orders of magnitude), Li and Be (one to two orders of magnitude). All waste waters transfer various contaminants into environmental subsystems and most actively modify the composition of the groundwaters. At the same time, dump drainage is a potentially important secondary source of valuable mineral components.

The distribution of the dynamic and thermal parameters of a gas in the immediate vicinity of a flame stabilizer (behind a rib and a backward-facing step 3 mm high) are studied. Data on the longitudinal and transverse velocity components, velocity pulsations, and correlations of pulsations in the boundary layer with combustion and without combustion are obtained using the PIV equipment. Temperature is measured with a thermocouple. Flame is visualized in the visible and ultraviolet regions. It is shown that in the flow attachment region near the leading edge of the flame, the gas velocity is close to the normal burning velocity. Heat release is estimated from the results of measurements. The presence of regions of volume and frontal combustion and kinetic and diffusion reaction is established. With increasing distance from the stabilizer, the heat-release rate decreases by more than an order of magnitude.

General trends in variations of the hydrogeological conditions at oil and gas fields, developed with the use of reservoir pressure maintenance by water injection, are discussed. The issues considered in the study include the vertical hydrogeochemical zonality of the Volga–Ural oil and gas basin, the composition of fresh water and oilfield brines, the character of their mixing under the effect of oil-production activities at oil deposits of roof and depression types. Data of many-year (1971–2011) hydrolithomonitoring with the use of trend analysis of hydrogeological data were used to reveal the direction of ecological–geochemical transformation of fresh groundwater and clay rocks in the aeration zone. New water–helium method was proposed to differentiate pollution sources between surface and deep and to identify the penetration pathways of oil brines into freshwater in the supergene zone.

The role of the gravitation factor in the formation of the hydrostratisphere in the East European evaporate basin is considered. The features of Paleozoic sedimentation are characterized, as are the mechanism and litho–hydrogeochemical effects of the density concentration convection of mother brines of the Low-Permian salt-bearing basin to the underlying terrigenous–carbonate Paleozoic and Proterozoic layers. It is shown that the convection processes resulted in the formation of multicomponent calcium chloride brines prevailing in the sedimentary layer of the basis; they also caused the metasomatic dolomitization of limestones with growth of their filtration capacity.

The features of the kinetics and hydrochemical effects of the exchange-absorption processes in the stratisphere of the Volga-Ural basin are considered. The dependence of these processes on the vertical geochemical zonality and their varied character over the basin depth are shown. The exchange-absorption nature on fresh sodium-hydrocarbonate and saline sodium-sulfate waters in the Upper-Permian sediments of the zone of hypergenesis is proved by the experiments and by physicochemical modeling in the water-terrigenous rock system. The exchange-absorption processes lose their hydrogeochemical significance and play no significant role in the formation of strong brines of the chlorine-calcium type in the zones of cata- and metagenesis under the submersion of Paleozoic and Late Proterozoic rocks to depths over 1000–3000 m.

Lines of Ne (3p-3s, 550–800 nm) and Xe (6p-6s, 800–1050 nm; 7p-6s, 475 nm) have been detected in the mechanoluminescence spectrum of terbium and cerium sulfate crystallohydrates. The luminescence of noble gas is observed jointly with the known bands of Ce3+ and Tb3+ ions and N*2 lines. The lines corresponding to excited Xe+ ions (500–550 nm), indicative of achievement of electric-field strengths on the order of 107 V/cm during mechanoluminescence, are also observed. It is established that, during mechanoluminescence of Tb2(SO4)3 · 8D2O in an argon atmosphere under a pressure of 1.3 atm, mechanochemical reactions of decomposition of crystallization water (D2O) molecules cause luminescence of OD radicals; this luminescence is initiated by electron impact occurring during electrization and in discharges in crystals during destruction.

The preparation and sonoluminescence of Cr(CO)6 nanodispersed suspensions in water, 83% H2SO4, and 74% H3PO4 are described for the first time. In the spectra of single- and multibubble sonoluminescence of these suspensions, chromium atom lines are found that are analogous to the corresponding lines in the sonoluminescence spectra of true Cr(CO)6 solutions in dodecane. Sonoluminescence of nanodispersed suspensions of metal carbonyl, by which the electronic temperature reached in the bubbles under sonolysis (from 6500 to 16 000 K in water and acids) was measured, expands the scope of the sonochemical model of injection of nanodroplets of low volatile compounds into cavitation bubbles due to the inclusion of injection of suspensions of insoluble substances into it.

The results of hydrological, ecological-hydrochemical, and hydrobiological studies, aimed at the protection and rational use of water resources of the Pavlovskoe Reservoir are considered. The results of experimental studies of the effect of submerged wood on water chemistry and the assessment of the ecological state of the reservoir based on phytoplankton data are given.

The flow in the vortex chamber with centrifugal fluidized bed of solid particles was studied experimentally and simulated numerically. The chambers of different configurations were considered, and this allowed us to change the ratio of centrifugal and gravity forces. To estimate the hydraulic losses in the vortex chamber, a simple model was suggested.