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Kurokawa H.,Saitama University | Yergaziyeva Y.G.,The Institute of Combustion Problems | Myltykbayeva L.K.,The Institute of Combustion Problems | Tayrabekova S.Z.,The Institute of Combustion Problems
Eurasian Chemico-Technological Journal | Year: 2016

Nickel catalysts supported on different carriers (θ-Al2O3, γ-Al2O3, HZSM-5 with γ-Al2O3, HZSM-5, and NaX) have been investigated for the partial oxidation of methane. All the supported nickel catalysts showed a high activity for the formation of synthesis gas, and γ-Al2O3 was the most effective among all the tested carriers. The effect of the heat-treatment temperature of the 3 wt.% Ni/γ-Al2O3 catalyst on its catalytic activity was studied, and a considerable decrease in its activity was observed by the heat-treatment of the catalyst at 1000 °C compared with the catalysts prepared by the 300–800 °C – calcination. The XRD analysis suggested the formation of NiAl2O4 that is a non-reducible compound at the high calcination temperature. The addition of a modifier (Co, Ce, or La) to the 3 wt.% Ni/γ-Al2O3 catalyst increased the selectivity to H2 and CO with the decreasing selectivity to CO2, and the highest selectivity to H2 was obtained by the 5 wt.% NiLa/γ-Al2O3. The developed 5 wt.% NiLa/γ-Al2O3 catalyst showed a high stability for 30 h for the partial oxidation of methane at 750 °C. The methane conversion reached 95%, selectivity to hydrogen 83% and 52% to carbon monoxide. © 2016 Al-Farabi Kazakh National University.

Beisenov R.,University of Houston | Beisenov R.,The Institute of Combustion Problems | Ebrahim R.,University of Houston | Mansurov Z.A.,The Institute of Combustion Problems | And 4 more authors.
Eurasian Chemico-Technological Journal | Year: 2013

Thick silicon carbide films were grown on sapphire (0001) and silicon (111) substrates using metal organic chemical vapor deposition (MOCVD). Diethylmethylsilane (DEMS) has been used as a single precursor, which contain Si and C atoms in the same molecule, without any carrier or bubbler gas. Atomic structure, surface composition and morphology have been investigated by XRD, AES, SEM and AFM analysis. SiC films of 5-7 micron thickness were grown at a rate of ~ 40 nm/min on sapphire (0001) and Si (111) substrates. The films grown at low temperature (850 °C and 900 °C) on both substrates show crystalline 3C-SiC in the (111) orientation. XRD results show that the orientation of the crystal structure does not depend of the substrate orientation AFM pictures of SiC films grown on sapphire (0001) exhibit more crystalline order as compared to films grown on the Si (111) substrates. AES of the grown films shows that in both cases the Si peak intensity is greater than that of carbon. This work shows promise for the development of alternative processes for developing low cost, large area substrates for application to IIInitrides LED and UV photodetector fabrication and also for gas detector application. © 2013 Al-Farabi Kazakh National University.

Duraia E.-S.M.,Texas State University | Duraia E.-S.M.,Suez Canal University | Beall G.W.,King Abdulaziz University | Mansurov Z.A.,The Institute of Combustion Problems | And 2 more authors.
Eurasian Chemico-Technological Journal | Year: 2013

Elongated wire-like Zinc oxide, nanocombs and nanocrystals have been successfully synthesized on the silicon substrate from the metallic zinc as a starting material. The annealing temperature was as low as 450 °C in argon atmosphere mixed with about 3% oxygen. Structural analysis using the X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) showed that the existence of two phases; nanowires and crystalline form. Moreover some nanoparticles aggregates were noticed to be attached in the bulk to the sides of the ZnO nanocrystals and sometimes these aggregate attached to the Zinc oxide hexagonal crystal and grow to form nanowire at different angles. Scanning electron microscopy (SEM) investigations for the zinc oxide nanostructure on the silicon substrate showed the formation of the nanocrystals in the gas flow direction and at the low energy sites over the silicon substrate. Photoluminescence (PL) measurements, performed at the room temperature, showed the existence of two basic emissions: narrow ultraviolet (UV) emission at 398 nm which attributed to the near band edge emission of the wide band gap and a very wide, more intensive, green emission at 471 nm corresponds to the crystal defects such as vacancies, interstitial sites in ZnO. © 2013 Al-Farabi Kazakh National University.

Mansurov Z.A.,The Institute of Combustion Problems | Prikhodko N.G.,The Institute of Combustion Problems | Lesbayev B.T.,The Institute of Combustion Problems | Auyelkhankyzy M.,The Institute of Combustion Problems
Eurasian Chemico-Technological Journal | Year: 2012

Influence of the direct electric current of different polarity on flame forms, soot yield, parameters of soot samples micro crystals (L a{cyrillic}, L c and d 002) and soot particles sizes in intensity range from 0.5 to 20 kV at electrode systems «needle-plane» at combustion of benzene-oxygen mixture at the ratio S{cyrillic}/O{cyrillic} = 1.0 with addition of 10% volume of argon at pressure 40 Torr was investigated. It was found that at positive polarity action of electric field rises to such a degree that at U ≥ 10 kV it leads to flame extinction. It is shown that maximum decrease in soot yield is observed at negative polarity. It was found that intensity range of electric field in which soot yield was 10 % more soot yield without applying electric field. It was shown that parameters of soot micro crystals on average remain constant irrespective of intensity and polarity. Fullerenes S{cyrillic} 60, S{cyrillic} 70 and PAH were identified in the extracts of soot samples by the method of IRspectroscopy. © 2012 al-Farabi Kazakh National University.

Mansurov Z.A.,The Institute of Combustion Problems | Mofa N.N.,The Institute of Combustion Problems
Eurasian Chemico-Technological Journal | Year: 2012

The peculiarities of the structure and morphology of quartz particles modified by carbon depending on MCT conditions and type of specific carbonaceous modifier were studied. Powder materials with the composition structure of the materials, which are hybrid formations organics-inorganics with a high chemical activity of its components, were obtained by combined MCT of carbon or carbon containing organic compounds with quartz. A high chemical activity of quartz particles modified by carbon is effectively realized when producing SHS-ceramics composition materials. The rate of redox processes increases, the initial reagents are most completely realized and nanosized particles of silicon carbide are formed. It is shown how one can regulate the process of combustion in SH-synthesis and produce the material of the necessary quality by modifying silicon dioxide particles in the course of MCT. © 2012 al-Farabi Kazakh National University.

Mansurov Z.A.,The Institute of Combustion Problems | Kerimkulova A.R.,The Institute of Combustion Problems | Ibragimova S.A.,Ma Aytkhozhins Institute Of Molecular Biology And Biochemistry | Gukenheimer E.Y.,Ma Aytkhozhins Institute Of Molecular Biology And Biochemistry
Eurasian Chemico-Technological Journal | Year: 2012

The article presents the results of physico-chemical studies on the development of nanostructured carbon materials from domestic raw materials. Were obtained and tested micro-mesoporous carbon sorbents for molecular-sieve chromatography of markers and investigated the applicability of carbon sorbents for the separation of protein-lipid complex, and plant bio-stimulator. Carbon sorbents have well-developed porous structure but their disadvantage is the weak mechanical strength. Recently it was shown that some carbon nanostructures have enormous strength. Thus arose the need to give the nano structured elements to carbon sorbent. Creating carbon sorbents containing nanocarbon structure was the aim of our study, as these by sorbents will be very useful for large-scale purification of biomolecules. The new carbon nanosorbent was prepared by carbonization of the stones of abricot seeds. The physico - chemical characteristics of nanostructured carbon sorbent was investigated by modern methods like scanning electrone microscope and infra red spectrophotometry. Based on the goal, nano-carbon materials in the laboratory of the Institute of Combustion Problems, Al-Farabi Kazakh National University synthesized nanostructured carbon sorbents - 'Nanokarbosorb' type for chromatography of biomolecules. It should be noted that the nanostructured elements of the frame attached to an unusually high mechanical strength to nanokarbosorb. Because of this, this sorbent can withstand high fluid pressure at work and has high durability, therefore, it can be used over the years. The sorbent has a very large porosity and large internal surface and, accordingly, a large capacity and has no parasitic sorption. Studies have shown that "Nanokarbosorb" suitable for purification of a powerful biostimulator plants. In this regard, of great interest represents nanostructured carbon sorbents with improved chromatography characteristics. Carbon sorbents known to mankind over thousands of years. They are widely used for purification of alcohol and other solutions. They are mechanically very weak and quickly attacked by fungi and bacteria. In this reason they are unconvenient large scale purification biomolecules. However, further improvement of chromatographic sorbents is impossible without the use of ideas and techniques of nanotechnology. © 2012 al-Farabi Kazakh National University.

Ksandopulo G.I.,The Institute of Combustion Problems
Eurasian Chemico-Technological Journal | Year: 2014

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 ccording 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 particlesget 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 presentedand presence o free valency in it has been identified. Production of free valency materials is of interest interms 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. © 2014 Al-Farabi Kazakh National University.

Mansurov Z.A.,The Institute of Combustion Problems
Eurasian Chemico-Technological Journal | Year: 2014

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 fames. 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 fame was studied. It is stated that the hydrophobic properties are due to the presence of soot particles in the form of nanobeads. © 2014 Al-Farabi Kazakh National University

Tileuberdi Y.,The Institute of Combustion Problems | Tileuberdi Y.,Al-Farabi Kazakh National University | Mansurov Z.A.,Al-Farabi Kazakh National University | Ongarbayev Y.K.,The Institute of Combustion Problems | And 2 more authors.
Eurasian Chemico-Technological Journal | Year: 2015

In the paper separation methods of organic part from oil sands were investigated at experimentally. For the determination of organic part (liquid fraction) of oil sands the extraction methods was used in Soxhlet apparatus by solvent. Thermal processing was carried out with a monotonic heating of oil sands from room temperature to 500 ºC. As showing results, organic part of Beke and Munayli-Mola oil sands studied by extraction method were 12.0 wt.% and 16 wt.%. Thermal processing results showed, that the organic part of Beke and Munayli-Mola oil sands were 9.6 wt.% and 13.5 wt.%. Physical and chemical characteristics of liquid fraction are established by standard methods. © 2015 Al-Farabi Kazakh National University.

Sultanov F.R.,Al-Farabi Kazakh National University | Sultanov F.R.,The Institute of Combustion problems | Tileuberdi Y.,Al-Farabi Kazakh National University | Tileuberdi Y.,The Institute of Combustion problems | And 6 more authors.
Eurasian Chemico-Technological Journal | Year: 2013

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. © 2013 Al-Farabi Kazakh National University.

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