bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of Asphaltene Structure Precipitated from Oil Sands
Authors: Sultanov F.R. , Tileuberdi Ye. , Ongarbayev Ye.K. , Mansurov Z.A. , Khasseinov K.A. , Tuleutaev B.K. , Behrendt F.
Published: November 2015

In the paper microscopic structure and physicochemical characteristics of asphaltenes were investigated. Asphaltene was precipitated from natural bitumen of oil sand of Munaily-Mola deposit using organic solvent of petroleum ether. According to results of our work, we found that the largest yield of asphaltens was reached by using the petroleum ether in 40-fold amount in relation to the initial hitch of bitumen. Chemical composition of precipitated asphaltenes aggregates were studied on FT-Infra red spectrometer Spectrum-65 at 450-4000 cm-1. At the Infrared spectrum, that the broad absorption band of asphaltenes at 3000-3600 cm-1 are characterizing the presence of polycyclic aromatic hydrocarbons and aliphatic chains in the samples of asphaltens. Elemental composition of the samples of asphaltenes on the installation of X-ray fluorescent spectrometer "Focus-M2". Also found the presence of two crystalline phases. One - quartz content is less than one percent. Another phase is also present in very small quantities and is represented by a single line of diffraction d = 4.158 Å. The microstructures and microanalysis of asphaltenes were investigated with an scanning electron microscopy (Quanta 3D 200i) at an accelerated voltage of 20 kV and a pressure of 0.003 Pa at National Nanotechnological Laboratory of Open Type of Kazakh National University. Microscopic images showed that the asphaltenes have a medium-ordered structure, the main component of the surface is
 represented by amorphous carbon.
SHS for Space Exploration
Authors: Sytschev A.E. , Vadchenko S.G. , Shcherbakov V.A. , Kamynina O.K. , Boyarchenko O.D. , Sachkova N.V.
Published: November 2015

For over past years, interest of leading space agencies (NASA, JAXA, ESA, RSA, etc.) in SHS experiments under microgravity conditions has been increasingly growing. The first SHS experiments during a parabolic flight in Russia and aboard the MIR Space station gave promising results. Similar studies are now
being carried out in various countries. The obtained data and assimilated experience have shown that SHS reactions can be used for (a) synthesis of high-porosity materials and regulation of structure formation in combustion products, (b) preparation of skeleton structures by combustion of particles suspended in vacuum, (c) generation of thermal energy, (d) generation of incandescent radiation, and (e) for in-space fabrication and in-situ repair works (welding, joining, cutting, coating, near-net-shape production, etc.). However, the results of the above studies (strongly scattered in the literature) still seem insufficient for elucidating the mechanism of combustion in. Indeed, the experiments were carried out by different researchers for a dozen
of systems and for strongly different duration of microgravity (drop towers, parabolic flight of a plane, parabolic flight of a spacecraft, in space stations). No correlation has been made with the available data of SHS studies (oriented largely on practical implementation) in conditions of artificial gravity. In experiments, the combustion wave has enough time to spread over the sample while the structure formation, may not have. This implies that the process of wave propagation should always be identical,
irrespective of the type of experimental technique and place of experiment. SHS experiments in space are attractive because (a) of low energy requirements, (b) processing cycle is short, (c) of process simplicity, (d) of versatility (wide range of suitable materials, and (e) the use of in-situ resources possible. To date, SHS experiments has already been performed aboard the International Space Station (ISS). Space technology has been developed for frontier exploration not only around the Earth orbit environment but also to the Moon, Mars, etc.
Electric Conductivity and Gas-Sensing Properties of Nickel Ferrite Thin Films Formed by Ion-Beam Sputtering Deposition
Authors: Busurin S.M. , Tsygankov P.A. , Busurina M.L. , Kovalev Yu. D. , Boyarchenko O.D. , Sachkova N.V. , Sytschev A.E.
Published: November 2015

Ferrites with composition of NiMnxFe1-xO4, (with x = 0 ÷ 1.0) have been synthesized by self-propagating high-temperature synthesis (SHS). The particle size of the synthesized ferrite powder was about 10 nm. Additional heat treatment at 1270 K during 50 min allowed us to obtained product with the single phase composition NiFe2O4. We found out that the increasing of the manganese content (x) increased the lattice constant of the ferrites from 0.833896 nm (x = 0) up to 0.836369 nm (x = 1). The synthesized powder contains two types of ferrite particles that are varied in size and shape. The magnetic properties significantly depend on the microstructure and chemical composition of synthesized ferrites. It has been found that the coercive force Hc increased from 1.75 (x = 0.2) to 2.85 (x = 1). By using of IBSD technology thin film of NiFe2O4 was sputtered on the Si (100) substrate. All sputtered films were X-ray transparent. The structure of ferrite films consisted of agglomerate less than 35 nm. The thickness of the sputtered film was about 600 nm. Additional heat treatment at 770 K during 90 min resulted to homogeneity of the film microstructure. The temperature range 400-750 K corresponds to working temperature range of gas-sensing devices. The ferrite compounds were studied by TOF-SIMS (Time-of-Flight Secondary-Ion-Mass-Spectrometry) for all depth of film. The resistivity R of synthesized film was 39 kΩ. Measurement of gas-sensing sensitivity RCH4/Rair for gas (2%v. CH4) – air mixture showed increase of R up to 12% at the present of methane at 403 K. For further research we plan to replace iron to manganese ions in chemical compounds of ferrite.
Chemical Dispersion as a Method for Segregation of Ultrafine and Nanosized Powders of SHS Refractory Compounds
Authors: Ignat’eva T. , Borovinskaya I.
Published: November 2015

Overviewed are some results of our recent works aimed at the synthesis of ultrafine and nanosized refractory powders by self-propagating high-temperature synthesis (SHS) combined with chemical dispersing of combustion products. The possible application of SHS for preparing ultrafine and nanosized powders of refractory compounds is examined. Specific features of SHS afford to affect not only the chemical/phase composition of products but also the morphology and size of synthesized particles. Quenching experiments have shown that the primary product particles formed in the combustion wave may have a size of below 0.1-0.2 μm. By etching a ground SHS cake with appropriate solutions, one can dissolve the defect-rich layers between the crystallites and remove impurities. As a result, the sinter cake breaks into crystalline particles of the same size as the primary crystallites, without compositional changes. This process was termed chemical dispersion. The phase and chemical composition, specific surface and grain size of SHS refractory compounds powders are detected before and after treatment. The influence of the synthesis conditions and the dispersion agent on the morphology and particle size of the resultant powders are ascertained. Successive chemical dispersing of raw products (carbides, nitrides, silicides, borides, oxides of metals and nonmetals) with solutions of different acids, alkalis, and salts leads to an additional grinding of the product, an increase in the specific surface and a decrease in the particle size. So, the possibility to control the SHS processes allows changing the particle size and structure of the synthesized compounds and provides obtaining high-quality products of the preset structure. The following thermochemical treatment of the ground cake by special solutions (chemical dispersion) allows to segregate ultra- and nanosized powders of refractory compounds. Our experience
in preparation, separation, and purification of SHS-produced nanopowders can be used as a basis for elaboration of general methodology for pilot-scale production of nanostructured compounds and composites.
Effect of Organic Additives on Silicon Combustion in Nitrogen
Authors: Barinova T. , Borovinskaya I.
Published: November 2015

The work shows some peculiarities of silicon combustion in nitrogen in the presence of additives of organic compounds. Organic compounds with different composition were used. Combustion of samples was carried out in a constant-pressure bomb. The combustion products are composite powders and containing α-,β- Si3N4, SiC, Si2N2O. The addition of organic additives suppressed coagulation of Si particles, improved the extent of conversion, and promoted combustion of coarse Si powders which can’t be ignited by any other methods. Introduction of organic dopants to Si powders was found to intensify their combustion without significant influence on the combustion temperature. Active transition of silicon to the gas phase occurs in the low-temperature zone of the combustion wave at the temperature lower than the melting point of silicon. At the temperatures lower than the melting point of Si the quenched combustion products contain two types of crystals of SiC and Si3N4. SiC is formed within a low-temperature zone of the combustion wave. SiC is formed by fine crystals and large spherical particulates which are formed by a bunch of very thin web-like crystals. SiC and Si3N4 formation provides a protective coating on silicon particles. It prevents coagulation at the temperature increase. The experiments have proved that it is enough to introduce 1-7 M of the organic additive to 1000 M of silicon for the combustion initiation. Meanwhile, adding different inorganic salts, including ammonium chloride, did not promote combustion. After initiation of combustion to continue Si
 powder must contain additives or organic compounds or addition of carbon black; carbon black is necessary for keeping the combustion on.
On a Possible Sustainable Petroleum Asssociated Gas Utilization in the Kashagan and Tengiz Regions, Kazakhstan
Authors: Lee Ch. , Kuchshenko K. , Carlsen L.
Published: November 2015

Associated petroleum gas (APG) is a form of natural gas, which is found associated with oil deposits. These gasses have traditionally been considered as unwanted byproducts in connection with oil exploitation. For decades the practice of flaring has been applied. However, this practice is highly controversial as it is environmentally polluting and economically unfavorable. Throughout the oil market this problem has high priority, and specifically in Kazakhstan. In the present paper possible ways to significantly reduce or eventually eliminate petroleum associated gas flaring in the Atyrau region, Kazakhstan are discussed. A particular focus is given to the Kashagan and Tengiz oilfields, which have high priority and potential for further growth in
the near future, and thus have a specific value for Kazakhstan both from political and economic points of view. It is concluded that despite a rush for short-term profit by Kazakhstan’s oil producers, an appropriate long-term strategy could not only be environmentally friendly but also financially beneficial. It is, however, also concluded that this requires a coordinated action involving the different players in the region as well as the Kazakh government. As an alternative it is suggested that a private consortium is formed being responsible for creating a unified system for processing and distribution of the APGs. The current flaring situation in Kashagan and Tengiz areas has been assessed applying the integrated environmental assessment framework DPSIR discussing the single elements: Driving forces, Pressures (on the environment), State (of the environment), Impact (on environmental and human helath) and Responses, respectively.
Photocatalytic Activity of ZnO-Biochar Hybrid Composites
Authors: Matos J. , Montaña R. , Rivero E. , Velasco J. , Ledezma G.
Published: November 2015

Photodegradation of methylene blue (MB) was studied on ZnO in presence of home-made biochars prepared by different methods. MB photodegradation was performed under UV-visible irradiation to verify the scaling-up of ZnO-AC hybrid materials. It was verified that oxygenated surface groups on carbon were photochemically active in the photodegradation of MB and a synergy effect between both solids has been estimated from the first-order apparent rate-constants. This effect enhances the photoactivity of ZnO up to a factor about 2.5 and the difference in photoactivity in the binary materials was associated to the surface properties of AC.
Experimental and Numerical Research in Explosive Loading of Two- and Three-Component Solid Mixtures
Authors: Ivanova O.V. , Zelepugin S.A. , Yunoshev A.S. , Sil’vestrov V.V.
Published: November 2015

We have conducted experimental and numerical research in two- and three-component solid mixtures placed into a cylindrical recovery ampoule under explosive loading. Behavior of the mixture is described by a mathematical model of a multicomponent medium. In the model, every component of a mixture simultaneously occupies the same volume as the mixture. Components interact with each other, exchanging momentum, energy, and mass (if the chemical reaction between the components occurs). An equality of components’ pressure is chosen as a condition for joint deformation of components. Finite element method is used for solving the problems. We considered experimentally and numerically explosive loading of the
aluminum-sulfur mixture, and explosive compaction of the aluminum-sulfur-carbon mixture in a cylindrical steel ampoule. The inert substance (graphite) was added to the mixture to avoid the reaction between aluminum and sulfur. Most of the focus is on simulating the action of explosion products on the ampoule.
In the computations the actions of the detonation products surrounding the ampoule was simulated by the action of pressure on the upper part of the ampoule in a vertical (axial) direction and on the lateral surface of the ampoule in a horizontal (radial) direction. We varied the thickness of the explosive that acts on the upper part of the ampoule in the axial direction in order to study the influence of the parameter on a final shape and size of the ampoule. We founded the essential influence of the thickness of the explosive layer on the final result of explosive compaction. Insufficient thickness of explosives, as well as the excessive thickness may be a reason for an incompletely compacted final product or lead to the formation of cracks or damage.
Self-Heating Model of Spherical Aluminum Nanoparticle Oxidation
Authors: Martirosyan K.S. , Ramazanova Z. , Zyskin M.
Published: November 2015

Aluminum-oxygen reaction is important in highly energetic and high pressure generating systems. Nanoenergetic thermites include mixtures of nanostructured Al and oxidizer particles. The main distinguishing features of these reactive systems are their significant enthalpy release and tunable rate of energy discharge, which gives rise to a wide range of combustion rates, energy release, and ignition sensitivity. In this paper, we consider rapid oxidation of a spherically symmetric aluminum particle. We use
the Cabrera Mott oxidation model to describe the kinetics of oxide growth of an aluminum nanoparticle and to predict reaction temperature and oxidation time. We assume that aluminum particle of diameter 10 to 50 nm is covered by a thin oxide layer (1-4 nm) and is surrounded by abundant amount of oxygen stored by oxidizers. The particle is rapidly heated up to ignition temperature to initiate self-sustaining oxidation reaction as a result of highly exothermic reaction. We numerically investigated the oxidation model by using COMSOL multiphysics software. The software creates a mesh fitted to geometric configuration of a
nanoparticle, and performs finite element method computations.
SH-Synthesis of Nanostructured Materials Based on SiO2+Al+CaSiO3 with Wollastonite after Ultrasonic Treatment
Authors: Mansurov Z.A. , Mofa N.N. , Sadykov B.S. , Shoibekova A.B.
Published: November 2015

This paper presents the results of a complex study of the structure and properties of wollastonite after ultrasonic treatment (UST) and its effect on the development of the process of technological combustion (SHS) of systems based on quartz, the structure and properties of synthesized composition materials. Ultrasonic treatment of wollastonite of the brand FW100 was carried out in water and 5% aqueous solutions of different alcohols and acids at 40 and 100 kHz as well as at simultaneous UST action of 40 and 100 kHz during 20-60 minutes. In the presence of different organic modifying additives during UST there takes place not only milling of wollastonite particles and erosion of their surface but also different complex structural changes on the surface of particles and their capsulation into colloidal conglomerates. All the structural changes taking place in wollastonite particles under the conditions of UST result also in the change of the chemical activity of the material, which effects the thermal characteristics of the combustion process (SH-synthesis) of the systems containing UST modified wollastonite in the charge mixture. It is stated that, when introducing wollastonite after ultrasonic treatment into SHS-charge, there takes place a more complete conversion of initial components in the combustion process. The greatest amount of corundum and nanocrystalline silicon is formed, when using wollastonite treated in water, aqueous solution of polyvinyl
alcohol and acetylsalicylic acid. The synthesized samples are characterized by high stable values of strength (up to 73 MPa) and indices of electric insulation properties.
Fabrication of Yttrium Ferrite Nanoparticles by Solution Combustion Synthesis
Authors: Saukhimov A.A. , Hobosyan M.A. , Dannangoda G.C. , Zhumabekova N.N. , Kumekov S.E. , Martirosyan K.S.
Published: November 2015

The ternary oxide system Y-Fe-O presents fascinating magnetic properties that are sensitive to the crystalline size of particles. There is a major challenge to fabricate these materials in nano-crystalline forms due to particle conglomeration during nucleation and synthesis. In this paper we report the fabrication of nano sized crystalline yttrium ferrite by solution combustion synthesis (SCS) where yttrium and iron nitrates were used as metal precursors with glycine as a fuel. The magnetic properties of the product can be selectively controlled by adjusting the ratio of glycine to metal nitrates. Yttrium ferrite nano-powder was obtained by using three concentration of glycine (3, 6 and 10 wt.%) in the initial exothermic mixture. Increasing glycine content was found to increase the reaction temperature of the system. The structural and magnetic properties of yttrium ferrite before and after annealing at temperature of 1000 °C were investigated by X-ray diffractometry, Differential Scanning Calorimetry (DSC) and cryogenic magnetometry (PPMS, Quantum Design). X-ray diffraction showed that, a broad diffraction peak was found for all samples indicating the amorphous nature of the product. Particle size and product morphology analysis identified that, Nitrate/glycine combustion caused considerable gas evolution, mainly carbon dioxide, N2 and H2O vapor, which caused the synthesized powders to become friable and loosely agglomerated for glycine concentration from 3 wt.% up to 10 wt.%. The study of the magnetic properties of produced materials in a metastable state was performed by measuring dependencies of Magnetization (M) on temperature, and magnetization on magnetic field strength between 5 K and 300 K. Magnetization measurements on temperature zero-fieldcooled and field-cooled show different patterns when the fraction of glycine is increased. The analysis of zero-field-cooled (ZFC), field-cooled (FC) and magnetization curves of annealed samples confirmed that nanoparticles exhibit superparamagnetic behavior. The increasing concentration of glycine leads to an increased blocking temperature.
The Efficiency of the Centrifuge is Force Action on the Propagation Mechanism of SHS-Wave
Authors: Ksandopulo G.I.
Published: November 2015

Adiabatic wave (AW) is generated by the effect of two forces, namely centrifugal and Coriolis forces, caused on the reaction of the self-propagating high-temperature synthesis (SHS). The synthesis occurs in the aluminothermic oxide system placed inside the heat insulated cylindrical reactor rotating around a vertical
axis. Actually there take place two processes during the SH synthesis: 1. separation of the reaction products, in particular aluminum (corundum) oxide concentrated on a quartz wall of the reactor and forming a tube; 2. formation of a coherent flow of liquid metal particles accelerating in the reactor axis direction according to its rotation speed and co-ordinates of Rх particle in the reactor. The size of the cluster representing particles practically does not change from the very moment of their generation as a result of the reaction due to their motion coherency. Considering the motion speed particles get inside a fresh combustible mixture deeper and deeper and, thus, initiate ignition of the accumulating reaction mixture. This provides growth of the heat release rate and transition of the process to the adiabatic mode. Metal clusters bearing kinetic energy and heat energy of the reaction (T = 2.8-3.5 thousand K) actually have a high energy potential that can increase according to growth of the rotation speed and longitudinal size of the reactor. So, if any highly endothermic reaction mixture takes place within a reactor co-ordinate with exponential growth of the moving clusters energy this reaction can be initiated and consequently will give start to numerous research capabilities. A real possibility of such rare and new materials synthesis technology is illustrated using as an example a reaction of the boron and aluminum oxides attacked by 92 m/s speed moving tungsten clusters with formation of a product from the intermediate boron and aluminum oxides and also tungsten and aluminum borides. The results of the synthesized oxide material study using a radio spectrometer has been presented and presence of free valency in it has been identified. Production of free valency materials is of interest in terms of their mixture with nanomaterilas and their compaction at ultrahigh pressure with the purpose to receive new materials with original mechanical, electric, photo-electric, and other properties. The references given below contain data on this technology studied previously.
Self-Propagating High-Temperature Synthesis of Silicon Carbide and Silicon Nitride Nanopowders Composition using Sodium Azide and Halides
Authors: Titova Yu.V. , Amosov A.P. , Bichurov G.V. , Maidan D.A.
Published: November 2015

Regularities of self-propagating high-temperature synthesis (SHS) or combustion synthesis (CS) by using “silicon – sodium azide – ammonium hexafluorosilicate – carbon – aluminum” powder mixture in the nitrogen atmosphere were investigated. The thermodynamic analysis of the combustion synthesis was performed. Experimental investigation of the combustion process: the measurement of linear rates of the combustion front propagation and the maximum combustion temperatures was conducted in a laboratory reactor with working volume 4.5 liters. The influence of the components ratio in the initial mixture on the combustion temperature, combustion rate and composition of reaction product was studied. The phase composition of the product synthesized was determined with an X-ray  diffractometer. It was disclosed that the SHS product consists of the composition (mixture) of silicon carbide nanopowder with silicon nitride whiskers and a final halide. Investigation of surface topography and morphology of the product particles was carried out with a scanning electron microscope. Optimal mixture for the synthesis of nanoscale composition based on silicon carbide was determined: “14Si+6NaN3+(NH4)2SiF6+15C+Al”. In this case, the SHS product consists of four phases: silicon carbide (β-SiC) – 48.57 wt.%, α-silicon nitride (α-Si3N4) – 27.04 wt.%, β-silicon nitride (β-Si3N4) – 5.83 wt.%, and sodium hexafluoroaluminate (Na3AlF6) – 18.56 wt.%. The average particle size of the composition was in the range of 70–130 nm. It was shown that the composition of the silicon carbide with silicon nitride and the final halide Na3AlF6 playing a role a flux can be used as a modifier of castable aluminum alloys and as a reinforcing phase of aluminomatrix composites.
Initiating Potential of Centrifugally Accelerated Metal Particles in the Inorganic Synthesis Reactions
Authors: Ksandopulo G.I. , Baideldinova A.N. , Omarova K.I. , Ainabayev A.M.
Published: November 2015

The method of producing clusters of various metals by using self-propagating high-temperature synthesis (SHS) in the conditions of high-speed rotation is presented. The purpose of a study is development of the technology of the acceleration of strong- endothermic reactions and synthesis of ceramic materials and products. The task of a experimental study consists of the observation of the wave of combustion in the effective layer, the determination of the coordinate of its passage in the adiabatic regime and the arrangement here of less effective layer for the purpose of obtaining gradient and composite materials. The possibility of the output of the process of the combustion of oxide system to the adiabatic regime is shown. The limits of inflammability in the centrifugal-force field come down by the attack of the adiabatic wave of combustion by accelerating the front of combustion with the molten particles of metal, returned into the zone of reaction by centrifugal acceleration. The potential possibility of using the centrifugal efforts for the production of ceramic materials was demonstrated for the multilayer aluminothermic systems. The speed of motion of metal particles under the influence of centrifugal acceleration is calculated. In the reactor of 30 cm long the speed of particles of tungsten reaches 94 m/s with a frequency of rotation of 3 000 rev/min received accelerated clusters of metals that are considered as possible sources of initiation of the chemical processes having about MJ/mol of activation energy. This method was allowed to produce gradient materials.
Features of Structural and Phase Transformations in Mo–Si–B and Сr–Al–Si–B Systems During Self-Propagating High-Temperature Synthesis
Authors: Potanin A.Yu. , Pogozhev Yu.S. , Levashov E.A. , Kovalev D.Yu. , Novikov A.V.
Published: November 2015

This study is dedicated to investigation of the combustion mechanisms during the SHS of ceramic materials in multicomponent Mo–Si–B and Cr–Al–Si–B systems. It is concluded that the following processes are defined the SHS for Si-rich Mo–Si–B compositions: Si melting, its spreading over the surfaces of the solid Mo and B particles, followed by B dissolution in the melt, and formation of intermediate Mo3Si-phase film. The subsequent diffusion of Si into Mo results in the formation of MoSi2 grains and MoB phase forms due to the diffusion of Mo into B-rich melt. The formation of MoB phase for B-rich compositions may occur via gas-phase mass transfer of MoO3 gaseous species to B particles and B2O2 to Mo particles. In Cr–Al–Si–B system firstly, the Al–Si eutectic mixture undergoes contact melting followed by formation of the reactionary surface as the eutectic melt spreads over the Cr and B particles surface. An increase in Al content increases the proportion of the Al–Si eutectic melt. The dissolution of Cr particles in this melt becomes the rate-limiting stage of the combustion process. The melt is saturated with these elements followed by crystallization of CrB and Cr(Si,Al)2 grains. In the Cr- and B-rich areas and low melt concentration, the formation of CrB may occur via gas-phase mass transfer of B2O2 gaseous species to Cr particles.  Consecutive formation of chromium and molybdenum borides and silicides is established by means of dynamic X-ray diffraction analysis. Compact ceramic samples were produced using forced SHS pressing technique. Their structural investigations were conducted by XRD and SEM.
Modeling of Pollutants in the Atmosphere Based on Photochemical Reactions
Authors: Danaev N.T. , Temirbekov A.N. , Malgazhdarov E.A.
Published: November 2015

This article is devoted to the problem of the propagation of harmful pollutants in the atmosphere from point sources taking into account photochemical transformations. A complete list of typical atmospheric pollutants of the industrial city was determined. The fifteen most common types of harmful substances such as NO2 (nitrogen dioxide), H2SO4 (sulfuric acid) to examine the transformation of impurities were selected. A scheme for the conversion of pollutants by chemical reactions was created. The transfer process and the transformation of substances were described by a system of differential equations. The resulting differential equations are constructed on the basis of stoichiometric formulas and the constant of reaction rate in accordance with the law of mass conservation. To account for the influence of anthropogenic heat sources and heterogeneity of the underlying surface on the propagation of harmful substances taking into photochemical reactions, a model of atmospheric boundary layer and the transport equation and transformation of pollutants by the example of the city of Ust-Kamenogorsk was considered. The schemes of stable and convergent difference for the equations of the atmospheric boundary layer and transport and transformation of admixture of harmful substances were designed. A software package for numerical simulation of air pollution taking into account photochemical transformations and corresponding visualization of scenarios was developed. The software package allows simulating the spread of pollutants under different weather conditions. The results of the daily monitoring of distribution and dynamics of the formation of chemical substances were obtained. The results of numerical simulation of the propagation and transformation of harmful impurities on mesometeorological background processes taking into account the terrain and water surfaces were presented. The analysis of the propagation of the substance concentration taking into the transformation of harmful substances of components was carried out. The results show that the description of photochemical reactions in the mathematical model proposed in this paper allows identifying areas which are heavily contaminated with salts such as MgSO4, CaSO4 and acids of H2SO4 with a reasonable accuracy due to the sequantial chemical reactions taking place in the atmosphere.
The Laser Active Element Based on Dye on Porous Alumina
Authors: Zeinidenov A.K. , Ibrayev N.Kh. , Aimukhanov A.K.
Published: November 2015

Luminescent properties of Rhodamine 6G in porous alumina matrix have been investigated. From the SEM images the pore diameter is determined to be ~ 50 nm and the distance between the pores to be about 250 nm. Specific surface area of nanoporous alumina films measured by gas adsorption (BET method) was 6 m2/g. Absorption and fluorescence spectra of Rhodamine 6G embedded in pores of anodic alumina oxide were measured. Decreasing of absorbance of monomers was observed upon increasing of Rhodamine 6G concentrations. At the same time appearing of new maximum at the short-wavelength part as a result of formation of dimer of dye was registered. Increasing of concentration of dye molecules in the pores leads to quenching of fluorescence of Rhodamine 6G. The lasing  characteristics were examined upon excitation of the samples by second harmonic Nd: YAG laser λgen = 532 nm, Еimp = 90 mJ, τ = 10 ns in the longitudinal form. The dye generation spectra in nanoporous alumina under different power densities of the pump source were measured. It is established that when the pumping source power is 0.4 MW/cm2 on the background spectrum of laser - induced fluorescence the narrow strip of the laser emission with a peak wavelength of 572 nm appears. Further increase in the power density of the pumping source leads to a narrowing of the band of generation and an increase in its intensity. The obtained results demonstrate the potential of using nanoporous alumina for creating the active elements of quantum electronics.
Palladium(II)-catalyzed Suzuki–Miyaura Reactions of Arylboronic Acid with Aryl Halide in the Presence of Aryl-Ferrocenyl-Phosphines
Authors: Khabiyev A.T. , Selenova B.S.
Published: November 2015

This study examined investigation of catalytic activity of aryl-ferrocenyl-phosphine (2-methoxyphenyl diferrocenyl phosphine (cat. 1), 2-tert-butyloxyphenyl diferrocenyl phosphine (cat. 2), 2-methoxynaphtyl diferrocenyl phosphine (cat. 3), 1,1’-bis(diphenylphosphino) ferrocene (cat. 4), phenyl diferrocenyl phosphine (cat. 5)) ligands with palladium salts as precursors in Suzuki–Miyaura reaction. Suzuki–Miyaura reaction is one of the important cross-coupling reactions and extremely powerful in forming C–C bonds. Aryl-ferrocenyl-phosphine ligands confer unprecedented activity for these processes, allowing reactions to be performed at low catalyst levels, to prepare extreme This study examined investigation of catalytic activity of aryl-ferrocenyl-phosphine (2-methoxyphenyl diferrocenyl phosphine (cat. 1), 2-tert-butyloxyphenyl diferrocenyl phosphine (cat. 2), 2-methoxynaphtyl diferrocenyl phosphine (cat. 3), 1,1’-bis(diphenylphosphino) ferrocene (cat. 4), phenyl diferrocenyl phosphine (cat. 5)) ligands with palladium salts as precursors in Suzuki–Miyaura reaction. Suzuki–Miyaura reaction is one of the important cross-coupling reactions and extremely powerful in forming C–C bonds. Aryl-ferrocenyl-phosphine ligands confer unprecedented activity for these processes, allowing reactions to be performed at low catalyst levels, to prepare extremely hindered biaryls and to be carried out, in general, also for reactions of aryl chlorides by temperature 100 ºC and pressure 1 atm. Sterically demanding and strongly Lewis-basic ferrocene-based phosphines are water- and oxygen-resistant. The Suzuki–Miyaura reaction is also an important reaction in the ground and fine organic synthesis, in the production of drugs and intermediates. To analyze the conversion of halogen aryl compounds the 1H NMR spectroscopy was used. The advantage of Suzuki–Miyaura reaction in comparison with other cross-coupling reactions (Kumada-, Heck-, Heck-Carbonylation-, Murahashi-, Sonogashira-, Negishi-, Stille-reaktion, etc.) is in the usage of low toxic, water- and oxygen-insensitive thermostable organoboron compounds. As boronic acid was used phenylboronic acid and as weak base – potassium phosphate. Catalyst, precursor and weak base were dissolved in toluene. All reactions were performed under an atmosphere of nitrogen or argon. The catalytic cycle of Suzuki–Miyaura reaction typically includes three main steps: oxidative addition of the haloaromatic to catalytic active palladium (0) species, transmetalation, and reductive elimination of the product under back formation of catalytically active species. All used catalysts showed good activity with aryl bromides and weak activity with aryl chlorides.
Synthesis of Novel 3,7-Diazabicyclo[3.3.1]nonane Derivatives
Authors: Malmakova A.Ye. , Praliyev K.D. , Welch J.T. , Iskakova T.K. , Ibraeva S.S.
Published: November 2015

A series of 3-(3-ethoxypropyl)-7-heterocyclylalkyl-3,7-diazabicyclo[3.3.l]nonan-9-ones have been prepared by Mannich cyclocondensation of 1-(3-ethoxypropyl)-4-oxopiperidine with paraformaldehyde and primary amines followed by Wolff-Kischner reduction of the obtained bispidinones. The starting 1-(3-ethoxypropyl)-4-oxopiperidine was synthesized by Dickmann condensation of 3-ethoxypropylamine with ethylacrylate. The 3,7-diazabicyclo[3.3.1]nonanones were obtained in acceptable yields by condensation of 1-(3-ethoxypropyl)piperidin-4-one with primary amines: 1-(3-aminopropyl)imidazole or 1-(2-aminoethyl) piperazine and formaldehyde in the presence of acetic acid in methanol medium. Reduction of the obtained bispidinones with hydrazine hydrate was carried out in the presence of KOH in triethylene glycol at 160-170 °C for 5 hours. The syntheses were performed under the atmosphere of N2. As the reaction products are viscous oils, the column chromatography (on III activity aluminum oxide, eluent – benzene: dioxane 5:1) was used for purification of novel bicyclic ketones and bicyclic nonanes. The completion of the reactions was monitored by TLC. Methods of 1H and 13C NMR spectroscopy were used to determine the structures of the substances synthesized. The prior studies have demonstrated that variation on the substituents at nitrogen atoms in 3- and 7-positions of bispidine cycle could result in the increase of biological activity and effect on compound spectral characteristics. Spatial structures of bispidinones and related bispidines were determined on the basis of the data of the 13C and 1H NMR spectra. A doublet of doublets of equatorial protons at C2.4 and C6.8 with large geminal constants of 10.5-11 Hz and vicinal constants of 3.0-6.0 Hz in 1H NMR spectrum revealed that those 3,7-diazabicyclo[3.3.1]nonane derivatives have a “chair-chair” conformation of both piperidine rings.
From Precursors to Pollutants: Some Advances in Combustion Chemistry Diagnostics
Authors: Krüger J. , Koppmann J. , Nau P. , Brockhinke A. , Schenk M. , Hansen N. , Werner U. , Kohse-Höinghaus K.
Published: November 2015

The present assessment and prediction of potential pollutant emissions from combustion systems often rely on dedicated combustion models. Their validation depends on the critical examination of the relevant chemical reaction pathways. To this end, a number of combustion diagnostic techniques are available
which can probe important chemical constituents in situ, thus providing direct information on the progress of the combustion reactions. Here, some recent experimental advances for the investigation of a suite of targets from molecular intermediates and soot precursors to nascent particles will be presented. Examples include the application of quantum cascade laser absorption spectroscopy (QCLAS), molecular-beam mass
spectrometry (MBMS) with different ionization schemes, photoelectron–photoion coincidence (PEPICO) spectroscopy, helium ion microscopy (HIM), and polarization-modulated infrared reflection–absorption spectroscopy (PM-IRRAS).
A Unified Reduced Model for Auto-Ignition and Combustion in Premixed Systems
Authors: Benzinger M.-S. , Schießl R. , Maas U.
Published: November 2015

In this paper, two complementary chemistry model reduction methods for combustion simulations are further developed and combined. A progress variable model (PVM), which follows the idea of trajectory generated manifolds (TGLDM), is tailored for describing auto-ignition in situations where the influence of
molecular transport on chemical reaction is weak, like auto-ignition in media with weak scalar gradients. The other model using the reaction diffusion manifold approach (REDIM) is designed for situations where the interaction of chemistry with molecular transport is essential. The formulation of both models is discussed and implementational issues of each single model are given. Also, each model is tested in its respective range of applicability (quasi-homogeneous combustion under steady/unsteady physical boundary conditions for the PVM, combustion in fields with essential scalar gradients for REDIM). The coupling of the two models into a unified model, which covers combustion in both regimes and during the transitions between regimes, is discussed, based on the global quasi-linearization concept (GQL).
Fuel-Air Mixing In A Turbulent Coannular Pipe Flow Measured Using Laser Absorption With Genetic Algorithm-Based Tomographic Reconstruction And Modeled With LES
Authors: Girard J.W. , Chen J.-Y. , Dibble R.W. , Janicka J. , Homma R.
Published: November 2015

This research aims at improving the knowledge base of fuel-air mixing through measurements and modeling. The measurements are from an improved tomographic reconstruction method that is relatively easy to accomplish. A novel aspect of this research is the use of tomography for generating the RMS of fuel concentration. Measurements of fuel concentration for a mixing field were tomographically reconstructed from time resolved line of sight laser absorption measurements. The modeling is done using large eddy simulations (LES). LES predictions were compared to measurements of the mean and RMS of fuel concentration. The LES model predicted time-averaged radial fuel concentration profiles to within 5%, and overpredicted the RMS of fuel concentration slightly, predicting the trends correctly.
Stability and Liftoff of a N2-in-H2 Jet Flame in a Vitiated Co-flow at Atmospheric Pressure
Authors: North A. , Frederick D. , Chen J.-Y. , Dibble R. , Gruber A.
Published: November 2015

The stability and liftoff characteristics of a nitrogen (N2) diluted hydrogen (H2) jet flame in a vitiated co-flow are investigated experimentally with particular attention focused on regimes where multiple stabilization mechanisms are active. Information gleaned from this research is instrumental for informing modeling approaches in flame transition situations when both autoignition and flame propagation influence combustion characteristics. Stability regime diagrams which outline the conditions under which the flame is attached, lifted, blown-out, and unsteady are experimentally developed and explored. The lifted regime is further characterized in determining liftoff height dependence on N2 dilution, jet velocity, and co-flow equivalence ratio (or essentially, co-flow temperature). A strong sensitivity of liftoff height to N2 dilution, jet velocity, and co-flow equivalence ratio is observed. Liftoff heights predicted by Kalghatgi’s correlation are unable to capture the effects of N2 dilution on liftoff height for the heated co-flow cases. A uniquely formulated Damköhler number, where the chemical time scale is based on flame propagation rather than autoignition, was therefore developed which acceptably captures the effects of jet velocity, nitrogen dilution and environment temperature on liftoff height. Satisfactory agreement between the correlation results indicate that stabilization is dominated by propagation, and prior studies with similar flames, such as the research of Muñiz and Mungal (1997) indicate that the propagating flame is likely tribrachial.
Non-Catalytic NOx Removal from Gas Turbine Exhaust with Cyanuric Acid in a Recirculating Reactor; Small Scale Evaluation and Industrial Application
Authors: Streichsbier M. , Dibble R.W. , Perry R.A.
Published: November 2015

A novel SNC technique to remove oxides of nitrogen (NOx) from stationary gas turbine exhaust has been investigated and applied. The technique employs the use of cyanuric acid (CYA), a non-toxic, dry powder, combined with the injection of auxiliary turbine fuel and recirculation. During the initial investigation, exhaust, generated by a 150 kW gas turbine, was treated in an insulated recirculation reactor, with a mean residence time of 0.65 to 0.71 seconds and a pressure drop of 660 Pa. In the reactor, autoignition of injected auxiliary gas turbine fuel raises the flue gas temperature to between 700 and 800 ºC. CYA slurry is injected. Temperature rise and NOx reduction occur simultaneously. Load following has been achieved. At all temperatures, significant NOx reduction from initial  concentrations of 106 to 124 ppm to as low as 18 ppm at 15% O2 have been observed. However, the process generates N2O emissions, which vary from 45 to 163 ppm, increasing with increasing CYA/NOx ratio. The ratio of N2O formed to NO removed was found to be between 1 to 1.5 to 1. The performance of CYA ((HNCO)3) is compared to that of ammonia (NH3) and urea ((NH2)2CO). A numerical model, which combines a detailed chemical kinetic mechanism with recirculation, has been developed. The model captures all observed trends well and is an invaluable guide to improved understanding of the interactive NOx removal process. The process was then successfully scaled up and applied to a variety of industrial 3.7 MW gas turbines and similarly significant NOx reduction has been achieved.
Soot and Nanomaterials Formation in Flame
Authors: Mansurov Z.A.
Published: November 2015

The seventieth anniversary of Professor Jürgen Warnatz is an important event for the scientific community of investigators of chemical kinetics and computation of combustion. His brilliant research in the field of combustion, particularly in the chemical kinetics reactions should be noted. His manuscript «Combustion»
with co-authors is a handbook for specialists in the field of combustion and under my supervision was translated to Kazakh. Professor J.Warnatz contributed much to the development of combustion processes modeling and education of scientists from various countries, including Kazakhstan. The general scheme of conversion of hydrocarbon fuels with new experimental data on the formation of fullerenes and graphenes, taking into account the pressure effect is proposed for the fuel-rich flames. It is shown that the formation of fullerenes is important to the corresponding spatial orientation of PAH, possible at low pressures. The formation of hydrophobic soot surface on silicon and nickel substrates during combustion of propane-oxygen flame was studied. It is stated that the hydrophobic properties are due to the presence of soot particles in the form of nanobeads.

 
The Importance of Detailed Chemical Mechanisms in Gas Turbine Combustion Simulations
Authors: Braun-Unkhoff M. , Goos E. , Kathrotia T. , Kick T. , Naumann C. , Slavinskaya N. , Riedel U.
Published: November 2015

This paper – in memory of Jürgen Warnatz – summarizes selected recent papers of the Chemical Kinetics Group at the German Aerospace Center in Stuttgart. It shows the need for detailed chemical reaction mechanisms to understand practical combustion systems. A comprehensive description of combustion processes based on detailed mechanisms is especially important in the design of new gas turbine combustion chambers and in the optimization of existing ones to improve efficiency and to reduce pollutant emissions, with fuel-flexibility and load-flexibility ever becoming more important. Different aspects of combustion processes where detailed reaction mechanisms provide useful insights will be covered in this paper: Fuels (alternative jet fuels, biomass based fuels), pollutants (soot), diagnostics (chemiluminescence), and thermochemistry. Furthermore, the underlying thermodynamics inevitably connected with detailed reaction schemes will be addressed. Exemplified results will be presented clearly demonstrating the predictive capabilities of detailed reaction mechanisms to be explored in computational fluid dynamic simulations to further optimize technical combustion systems.