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Item Metadata only A new step in the development of Zn/LiFePO4 aqueous battery(2017-01-01) Molkenova, A.; Belgibayeva, A.; Ibrayeva, D.; Sultanov, M.; Zhumagali, S.; Akhmetova, N.; Hara, T.; Bakenov, Z.; A., MolkenovaAbstract In recent years, aqueous batteries have gained much attention due to their low production cost and exceptional safety compared to commercial Li-ion battery systems. Three-dimensional (3D) structure could be promising to enhance these batteries energy capacity. In this work, the electrochemical performance of 3D Zn electrode, developed for aqueous rechargeable Zn/LiFePO4 (Zn/LFP) battery system, was studied. Formation of uniformly coated Zn metal on the three-dimensionally organized carbon fibers was verified by field emission scanning electron microscopy (FE-SEM). The electrochemical performance of the battery with this anode was tested for over 50 cycles, where the initial capacity decayed by 11%. Further, poly(methyl methacrylate) (PMMA) and poly(p-phenylene oxide) (PPO) polymer coatings were extensively investigated as a potential separator for the 3D aqueous battery system. Cyclability of PMMA-coated Zn anode was better than that of “plane” Zn; however, the initial capacity of 3D Zn anode was lower than that for the counterpart system.Item Open Access Atomistic and Kinetic Simulations of Radiation Damage in Molybdenum(2012 MRS Spring Meeting, 2012-04) Rest, J.; Yacout, A. M.; Ye, B.; Yun, D.; Kuksin, A. Y.; Norman, G. E.; Stegailov, V. V.; Yanilkin, A. V.; Insepov, Z.A new Mo potential, developed recently by using an ab initio quantum mechanics theory, was used to study formation and time evolution of radiation defects, such as self-interstitial atoms (SIAs), vacancies, and small clusters of SIAs, using molecular dynamics (MD). MD models were developed for calculation of the diffusion coefficients of vacancies, self-interstitials, and small dislocation loops containing 2 to 37 SIAs; and the rate constants were calculated. Interactions of small SIA loops with SIAs were simulated. The results show that rotation of SIA from one 〈111〉 to another equivalent direction is an important mechanism that significantly contributes to kinetic coefficients.Item Metadata only Computer simulation and visualization of supersonic jet for gas cluster equipment(2015-09-21) Ieshkin, A.; Ermakov, Y.; Chernysh, V.; Ivanov, I.; Kryukov, I.; Alekseev, K.; Kargin, N.; Insepov, Z.; A., IeshkinAbstract Supersonic nozzle is a key component of a gas cluster condensation system. We describe a flow visualization system using glow discharge with annular or plane electrodes. The geometric parameters of a supersonic jet under typical conditions used in a gas cluster ion beam accelerator are investigated. As well numerical simulations were performed. Dependence of inlet and ambient pressures and nozzle throat diameter on the shock bottle dimensions is described for different working gases. Influence of condensation rate on shock bottle axial size is discussed.Item Open Access Computer simulation and visualization of supersonic jet for gas cluster equipment(Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2015-09-21) Ermakov, Y.; Chernysh, V.; Ivanov, I.; Ieshkin, A.; Kryukov, I.; Alekseev, K.; Kargin, N.; Insepov, Z.; Ieshkin, A.Abstract Supersonic nozzle is a key component of a gas cluster condensation system. We describe a flow visualization system using glow discharge with annular or plane electrodes. The geometric parameters of a supersonic jet under typical conditions used in a gas cluster ion beam accelerator are investigated. As well numerical simulations were performed. Dependence of inlet and ambient pressures and nozzle throat diameter on the shock bottle dimensions is described for different working gases. Influence of condensation rate on shock bottle axial size is discussed.Item Open Access Cooperation benefits of Caspian countries in their energy sector development(2014-08-01) De Miglio, Rocco; Akhmetbekov, Yerbol; Baigarin, Kanat; Bakdolotov, Aidyn; Tosato, GianCarlo; Rocco, De MiglioAbstract This paper studies the development possibilities of the energy systems of four Central Asia and Caspian countries. It explores options that improve their domestic energy efficiencies and increase their export of fossil energy commodities. Using the MARKAL-TIMES modelling tool, it represents their energy system with a bottom-up partial economic equilibrium growth model. With the help of scenario analyses, it evaluates the direct economic advantage of improving the domestic energy efficiencies. Furthermore it calculates the direct economic advantage of cooperation. It finds out that a new/different geo-economic attitude brings USD billions of annual economic benefits, particularly if the countries aim to differentiate their export routes, increase the amount of export and contribute to climate change mitigation.Item Metadata only Corrigendum to “Three-dimensional imaging of polymer materials by scanning probe tomography” [Eur. Polym. J. 52 (2014) 154–165](2014-06-01) Alekseev, Alexander; Efimov, Anton; Loos, Joachim; Matsko, Nadejda; Syurik, Julia; Alexander, AlekseevItem Open Access CREATION OF AN INNOVATIVE ROBOT WITH A GRIPPER FOR MOVING PLANT MICROSHOOTS FROM THE IN VITRO TRANSPORT TANK TO THE WORKING TANK WITH SOIL GROUND AT THE STAGE OF THEIR ADAPTATION IN SOIL GROUND DURING MICROCLONAL REPRODUCTION(Eastern-European Journal of Enterprise Technologies, 2022-03-28) Kaimov, Abylay; Syrgaliyev, Yerzhan; Tuleshov, Amandyk; Kaimov, Suleimen; Kaiym, Talgat; Kaimov, Aidarkhan; Primbetova, Altynay; Gribanov, VitalyThe industrial development of cities is the main cause of the destruction and degradation of natural resources around the world. Urbanization negatively affects the species composition of plants, the atmosphere and soil cover of areas of populated areas of large cities of the World. Tree plantations are the main mechanism for stabilizing the ecological situation in large cities and arid territories of the countries of the World. In this regard, in order to obtain a large number of genetically identical plants using their micropropagation, it is necessary to automate the main stages of this technological process. The result of the study is the creation of an adaptive phalanx gripper of a robotic complex for automating the technological process of handling operations. That will have a positive effect on solving the urgent problem of planting greenery in large cities and areas of arid territories not only in the Republic of Kazakhstan, but also in other countries of the World and represents a fundamentally new approach to solving the environmental problems of the Earth. The article substantiates various options for structural-kinematic schemes of the robot gripper, taking into account the stochastic conditions of its interaction with the overloaded object. Mathematical methods have been created for the selection and justification of the geometric, structural-kinematic and dynamic parameters of grippers for overloading plant microshoots and their computer 3D models. Software has been developed for modeling the functioning of a remotely controlled physical prototype of a mobile robot with an adaptive gripper for reloading microshoots from a transport tank to a cargo tank.Item Metadata only Electrodeposited Ni-Sn intermetallic alloy electrode for 3D sulfur battery(2017-01-01) Tolegen, B.; Adi, A.; Aishova, A.; Bakenov, Z.; Nurpeissova, A.; B., TolegenAbstract 3D architecture appeared to be a promising design to enhance the performance of the Lithium-ion batteries by shortening the lithium ion diffusion path and increasing the energy density per unit area. In this paper, we report preliminary results of facile electrodeposition of intermetallic tin-nickel alloy from electrolyte solution onto 3D structured nickel foam for 3D lithium-sulfur battery. The coated films were characterized for their morphologies, structural and electrochemical properties. Scanning electron microscope images revealedthin and homogenous film while XRD revealed the expected phase of intermetallic alloy Ni3Sn4. The electrochemical activity of the film showed to be a promising start to be used as an anode material and needs further works to be optimized.Item Open Access Emptying Water Towers? Impacts of Future Climateand Glacier Change on River Discharge in theNorthern Tien Shan, Central Asia(MDPI, 2020-02-26) Zhumabayev, Dauren; Shahgedanova, Maria; Afzal, Muhammad; Hagg, Wilfried; Kapitsa, Vassiliy; Kasatkin, Nikolay; Mayr, Elizabeth; Rybak, Oleg; Saidaliyeva, Zarina; Severskiy, Igor; Usmanova, Zamira; Wade, Andrew; Yaitskaya, Nataliampacts of projected climate and glacier change on river discharge in five glacierized catchments in the northern Tien Shan, Kazakhstan are investigated using a conceptual hydrological model HBV-ETH. Regional climate model PRECIS driven by four different GCM-scenario combinations (HadGEM2.6, HadGEM8.5, A1B using HadCM3Q0 and ECHAM5) is used to develop climate projections. Future changes in glaciation are assessed using the Blatter–Pattyn type higher-order 3D coupled ice flow and mass balance model. All climate scenarios show statistically significant warming in the 21st Century. Neither projects statistically significant change in annual precipitation although HadGEM and HadCM3Q0-driven scenarios show 20–37% reduction in July–August precipitation in 2076–2095 in comparison with 1980–2005. Glaciers are projected to retreat rapidly until the 2050s and stabilize afterwards except under the HadGEM8.5 scenario where retreat continues. Glaciers are projected to lose 38–50% of their volume and 34–39% of their area. Total river discharge in July–August, is projected to decline in catchments with low (2–4%) glacierization by 20–37%. In catchments with high glacierization (16% and over), no significant changes in summer discharge are expected while spring discharge is projected to increase. In catchments with medium glacierization (10–12%), summer discharge is expected to decline under the less aggressive scenarios while flow is sustained under the most aggressive HadGEM8.5 scenario, which generates stronger melt.Item Restricted In situ TEM investigation of Xe ion irradiation induced defects and bubbles in pure molybdenum single crystal(Journ al of Nuclear Materials, 2013-06-30) Yun, D.; Kirk, Marquis A.; Baldo, Peter M.; Rest, J.; Yacout, A. M.; Insepov, Z.; Yun, DiAbstract In order to study irradiation damage and inert gas bubble formation and growth behaviors, and to provide results and insights useful towards the validation of a multi-scale simulation approach based on a newly developed Xe–Mo inter-atomic potential, in situ Transmission Electron Microscopy (TEM) studies of Xe implantations in pure single crystal Molybdenum (Mo) have been conducted. 300keV and 400keV Xe+ ion beams were used to implant Xe in pre-thinned TEM Mo specimens. The irradiations were conducted at 300°C and 600°C to ion fluence up to 4×1016ions/cm2.In situ TEM characterization allows detailed behaviors of defect clusters to be observed and is very useful in illustrating defect interaction mechanisms and processes. Dislocation loops were found to form at relatively low irradiation fluence levels. The characterization results showed that the free surfaces, formed in the process of producing pre-thinned specimens, play an important role in influencing the behaviors of dislocation loops. Similar characterizations were conducted at high fluence levels where Xe gas bubbles can be clearly observed. Xe gas bubbles were observed to form by a multi-atom nucleation process and they were immobile throughout the irradiation process at both temperatures. Measurements on both the number density and the size of dislocation loops and gas bubbles were taken. The results and implications of the measurements are discussed in this paper.Item Open Access Intelligent voice system for kazakh(Journal of Physics: Conference Series, 2014-04-04) Yessenbayev, Z.; Saparkhojayev, N.; Tibeyev, T.Modern speech technologies are highly advanced and widely used in day-to-day applications. However, this is mostly concerned with the languages of well-developed countries such as English, German, Japan, Russian, etc. As for Kazakh, the situation is less prominent and research in this field is only starting to evolve. In this research and applicationoriented project, we introduce an intelligent voice system for the fast deployment of callcenters and information desks supporting Kazakh speech. The demand on such a system is obvious if the country’s large size and small population is considered....Item Open Access INVESTIGATION OF POWER AND FORCE PARAMETERS OF PRESSING OF PRECISIONS AT THE CONTINUOUS PRESSING MILL OF NEW CONSTRUCTION(SERIES OF GEOLOGY AND TECHNICAL SCIENCES, 2020) Mashekov, S. A.; Nugman, E. Z.; Mashekova, A. S.; Bekbosynova, B. A.; Tussupkaliyeva, E. A.; Absadykov, B. N.In the article, by using the direct method in the calculus of variations, the mechanism of deformation force development in the matrix, when pressing rods in a new device with is considered, in addition the kinematics of the process is analytically analyzed and the forces acting on the screw-like rolls of this device are calculated. On the basis of the calculated data, it is established that the pressing stress decreases with increasing torques applied to the screw-like rolls of the proposed device. It is proved that with increasing the value of the input angle of the matrix, the forces and the pressing torque are increased. It is shown that the direction of friction forces exerts a significant influence on the pressing stress. The smallest force and the pressing torque are obtained with an angle of friction forces of 45°. The conducted researches made it possible to obtain new scientific data on the force parameters of rod pressing on a new device, and the practical application of the results of the study will ensure an increase in the efficiency of the manufacturing processes of bar productsItem Metadata only Low temperature synthesis of graphene nanocomposites using surface passivation of porous silicon nanocrystallites with carbon atoms(2019-02-28) Tynyshtykbayev, Kurbangali B.; Ainabаyev, Ardak; Kononenko, O.; Chichkov; Insepov, Z.; Tynyshtykbayev, Kurbangali B.Abstract This work presents the experimental investigation of the synthesis of graphene carbon nanocomposites (CNC-G) by carbonization of porous silicon (PS) using CVD method at low temperature of T = 350–500 °C. The low-temperature synthesis of CNC-G is explained by a low melting temperature of porous silicon nanocrystallites (nc-PS) formed during electrochemical etching.Item Metadata only MoS2 nanopowder as anode material for lithium-ion batteries produced by self-propagating high-temperature synthesis(2017-01-01) Bozheyev, Farabi; Zhexembekova, Anar; Zhumagali, Shynggys; Molkenova, Anara; Bakenov, Zhumabay; Farabi, BozheyevAbstract Due to continuous rise of demand for powerful energy sources for portable applications, high energy density and efficiency rechargeable batteries are under constant development. Currently, the most widely used power source for such applications is rechargeable lithium-ion batteries (LIBs). To increase the energy density, rate capability and cyclability of LIBs, alternative anode materials, such as MoS2, are under intensive investigation. The layered structure of MoS2 resembles graphite, and its theoretical specific capacity is about twice higher than that of graphite (670 mAh g-1 against 372 mAh g-1) due to its higher interlayer spacing (∼0.6 nm) for a Li-ion intercalation. In this work MoS2 nanopowder (MoS2-NP), prepared by self-propagating high-temperature synthesis (SHS), is used as an anode material (MoS2/C composition) for LIBs, and its electrochemical properties were analyzed. The MoS2-NP anode exhibited the initial charge capacity of 567 mAh g-1 at a current density of 50 mAh g-1. This performance will be improved by introduction of MoS2-NP into various carbon-containing composites.Item Restricted A multiscale method for the analysis of defect behavior in Mo during electron irradiation(Computational Materials Science, 2014-10-31) Rest, J.; Ye, B.; Yun, D.; Insepov, Z.; Rest, J.Abstract In order to overcome a lack of experimental information on values for key materials properties and kinetic coefficients, a multiscale modeling approach is applied to defect behavior in irradiated Mo where key materials properties, such as point defect (vacancy and interstitial) migration enthalpies as well as kinetic factors such as dimer formation, defect recombination, and self interstitial–interstitial loop interaction coefficients, are obtained by molecular dynamics calculations and implemented into rate-theory simulations of defect behavior. The multiscale methodology is validated against interstitial loop growth data obtained from electron irradiation of pure Mo. It is shown that the observed linear behavior of the loop diameter vs. the square root of irradiation time is a direct consequence of the 1D migration of self-interstitial atoms.Item Open Access Multiscale simulation models of Xe bubble formation in irradiated Mo(Transactions of the American Nuclear Society, 2012) Starikov, S. V.; Yun, D.; Yacout, A. M.; Insepov, Z.Multiscale simulation models for Xe bubble nucleation and growth in irradiated Mo were developed that consist Ab-initio calculations of the interatomic potentials for the Mo and Xe-Mo systems, atomistic MD simulations of the kinetic rate coefficients of radiation defects, and nucleation mechanisms of Xe bubbles in Mo. Simulations of various Xe concentrations, temperatures and pressures were carried out. A critical concentration of Xe atoms was determined at which the nucleation occurs spontaneously.Item Open Access Nanometer size hole fabrication in 2d ultrathin films with cluster ion beams(American Institute of Physics Inc., 2017-07-24) Ainabayev, A.; Kirkpatrick, S.; Walsh, M.; Vyatkin, A. F.; Insepov, Z.Gas cluster ion beams are proposed as a new tool for producing nanometer sized holes in ultrathin 2D films. Surfaces of films of graphene, graphene oxide, MoS2, and HOPG, and also silicon as a reference, were irradiated by Ar gas cluster ion beams (Exogenesis Corporation, Billerica, MA USA). The results were analyzed using atomic force microscopy (AFM) and Raman spectroscopy. Ar gas cluster ion acceleration energy was 30 keV and total ion fluences ranged from 1108 to 11013 cm-2. Uniformly distributed holes, typically in the range of 10 to 25 nanometers in diameter, produced by the cluster ions, were observed on the surface of graphene oxide. To the best of our knowledge, this is first experimental observation of such holesItem Open Access Optical Emission of the Nuclear-Induced Plasmas of Gas Mixtures(International Journal of Optics, 2014-04-24) Khasenov, Mendykhan U.The characteristic properties of the inverted-population-forming processes in lasers with ionizing pumping are considered. Results obtained fromresearch of active lasermedia concerning the p-s transitions of atoms of neon, mercury, and cadmium are presented. The feasibility of ion-ion recombination in lasers with nuclear pumping is discussed. The excitation kinetics of the first negative system of CO, heteronuclear ionic molecules of inert gases, and halogenides of inert gases under ionizing radiation are considered.Item Open Access Photon propagation in slowly varying inhomogeneous electromagnetic fields(American Physical Society, 2015-04) Karbstein, Felix; Shaisultanov, RashidStarting from the Heisenberg-Euler effective Lagrangian, we determine the photon current and photon polarization tensor in inhomogeneous, slowly varying electromagnetic fields. To this end, we consider background field configurations varying in both space and time, paying special attention to the tensor structure. As a main result, we obtain compact analytical expressions for the photon polarization tensor in realistic Gaussian laser pulses, as generated in the focal spots of high-intensity lasers. These expressions are of utmost importance for the investigation of quantum vacuum nonlinearities in realistic high-intensity laser experiments.Item Open Access Pole dark energy(Physical Review, 2019-11) Linder, E. V.Theories with a pole in the kinetic term have been used to great effect in studying inflation, owing to their quantum stability and attractor properties. We explore the use of such pole kinetic terms in dark energy theories, finding an interesting link between thawing and freezing models, and the possibility of enhanced plateaus with ``superattractor''-like behavior. We assess the observational viability of pole dark energy, showing that simple models can give dark energy equation of state evolution with w(z)<−0.9 even for potentials that could not normally achieve this easily. The kinetic term pole also offers an interesting perspective with respect to the swampland criteria for such observationally viable dark energy models....