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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 Source

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. Source

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. Source

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. Source

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. Source

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