03.NU Research and Innovation System
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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 A Personal View on a Zero Carbon Future(International Scientific and University Conference. "Climate Change and CO2 Emission Reduction" 12-13 July, 2017, 2017-07-12) Winter, AxelItem Open Access Accelerated Parameter Estimation with DALE X(NURIS; Energetic Cosmos Laboratory, 2017-05-08) Daniel, Scott F.; Linder, Eric V.We consider methods for improving the estimation of constraints on a high-dimensional parameter space with a computationally expensive likelihood function. In such cases Markov chain Monte Carlo (MCMC) can take a long time to converge and concentrates on finding the maxima rather than the often-desired confidence con-tours for accurate error estimation. We employ DALEχ(Direct Analysis of Limits via the Exterior ofχ2) for determining confidence contours by minimizing a cost function parametrized to incentivize points in parameter space which are both on the confidence limit and far from previously sampled points. We compare DALEχ to the nested sampling algorithm implemented in MultiNest on a toy likelihood function that is highly non-Gaussian and non-linear in the mapping between parameter values and χ2. We find that in high-dimensional cases DALEχfinds the same confidence limit as Multi-Nest using roughly an order of magnitude fewer evaluations of the likelihood function.DALE χ is open-source and available athttps://github.com/danielsf/Dalex.git.Item Open Access Accelerated Parameter Estimation with DALEX(International conference "ECL17: Exploring the Energetic Universe 2017", Nazarbayev University Energetic Cosmic Laboratory, 2017-05-02) Daniel, Scott F.; Linder, Eric V.We consider methods for improving the estimation of constraints on a high-dimensional parameter space with a computationally expensive likelihood function. In such cases, Markov chain Monte Carlo (MCMC) can take a long time to converge and concentrates on finding the maxima rather than the often-desired confidence contours for accurate error estimation. We employ DALEχ (Direct Analysis of Limits via the Exterior of χ2) for determining confidence contours by minimizing a cost function parametrized to incentivize points in parameter space which are both on the confidence limit and far from previously sampled points. We compare DALEχ to the nested sampling algorithm implemented in MultiNest on a toy likelihood function that is highly non-Gaussian and non-linear in the mapping between parameter values and χ2. We find that in high-dimensional cases DALEχ finds the same confidence limit as Multi-Nest using roughly an order of magnitude fewer evaluations of the likelihood function. DALEχ is open-source and available at https://github.com/danielsf/Dalex.git .Item Unknown Association of renewable energy of Kazakhstan(International Scientific and University Conference. "Climate Change and CO2 Emission Reduction" 12-13 July, 2017, 2017-07-12) Kashkinbekov, ArmanItem Open Access The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Constraining modified gravity(American Physical Society, 2016-12-02) Mueller, Eva-Maria; Percival, Will; Linder, Eric; Alam, Shadab; Zhao, Gong-Bo; Sanchez, Ariel G.; Beutler, FlorianWe use baryon acoustic oscillation and redshift space distortion from the completed Baryon Oscillation Spectroscopic Survey, corresponding to data release 12 of the Sloan Digital Sky Survey, combined sample analysis in combination with the cosmic microwave background, supernova and redshift space distortion measurements from additional spectroscopic surveys to test deviations from general relativity. We present constraints on several phenomenological models of modified gravity.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 Constraining dark energy dynamics in extended parameter space(American Physical Society, 2017-07-19) Di Valentino, Eleonora; Melchiorri, Alessandro; Linder, Eric V.; Silk, JosephDynamical dark energy has been recently suggested as a promising and physical way to solve the 3 sigma tension on the value of the Hubble constant H0 between the direct measurement of Riess et al. (2016) (R16, hereafter) and the indirect constraint from cosmic microwave anisotropies obtained by the Planck satellite under the assumption of a ΛCDM model. In this paper, by parametrizing dark energy evolution using the w0−wa approach, and considering a 12 parameter extended scenario, we find that: (a) the tension on the Hubble constant can indeed be solved with dynamical dark energy, (b) a cosmological constant is ruled out at more than 95% c.l. by the Planck+R16 dataset, and (c) all of the standard quintessence and half of the “downward going” dark energy model space (characterized by an equation of state that decreases with time) is also excluded at more than 95% c.l. These results are further confirmed when cosmic shear, CMB lensing, or SN Ia luminosity distance data are also included. The best fit value of the χ2 for the Planck+R16 data set improves by Δχ2=−12.9 when moving to 12 parameters respect to standard ΛCDM. However, tension remains with the BAO dataset. A cosmological constant and small portion of the freezing quintessence models are still in agreement with the Planck+R16+BAO data set at between 68% and 95% c.l. Conversely, for Planck plus a phenomenological H0 prior, both thawing and freezing quintessence models prefer a Hubble constant of less than 70 km/s/Mpc. The general conclusions hold also when considering models with nonzero spatial curvature.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 Cosmic Growth Signatures of Modified Gravitational Strength(International conference "ECL17: Exploring the Energetic Universe 2017", Nazarbayev University Energetic Cosmic Laboratory, 2017-03-02) Denissenya, Mikhail; Linder, Eric V.Cosmic growth of large scale structure probes the entire history of cosmic expansion and gravitational coupling. To get a clear picture of the effects of modification of gravity we consider a deviation in the coupling strength (effective Newton’s constant) at different redshifts, with different durations and amplitudes. We derive, analytically and numerically, the impact on the growth rate and growth amplitude. Galaxy redshift surveys can measure a product of these through redshift space distortions and we connect the modified gravity to the observable in a way that may provide a useful parametrization of the ability of future surveys to test gravity. In particular, modifications during the matter dominated era can be treated by a single parameter, the “area” of the modification, to an accuracy of 0.3% in the observables. We project constraints on both early and late time gravity for the Dark Energy Spectroscopic Instrument and discuss what is needed for tightening tests of gravity to better than 5% uncertainty.Item Open Access Cosmic Growth Signatures of Modified Gravitational Strength(NURIS; Energetic Cosmos Laboratory, 2018-09-05) Denissenya, Mikhail; Linder, Eric V.Cosmic growth of large scale structure probes the entire history of cosmic expansion and gravitational coupling. To get a clear picture of the effects of modification of gravity we consider a deviation in the coupling strength (effective Newton’s constant) at different redshifts, with different durations and amplitudes. We derive, analytically and numerically, the impact on the growth rate and growth amplitude. Galaxy redshift surveys can measure a product of these through redshift space distortions and we connect the modified gravity to the observable ina way that may provide a useful parametrization of the ability of future surveys to test gravity. In particular, modifications during the matter-dominated era can be treated by a single parameter, the “area” of the modification, to an accuracy of∼0.3% in the observables. We project constraints on both early and late time gravity for the Dark Energy Spectroscopic Instrument and discuss what is needed for tightening tests of gravity to better than 5% uncertaintyItem 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 Open Access Debiasing Cosmic Gravitational Wave Sirens [Article](NURIS; Energetic Cosmos Laboratory, 2019-05-27) Keeley, Ryan E.; Shafieloo, Arman; L'Huillier, Benjamin; Linder, Eric V.Accurate estimation of the Hubble constant, and other cosmological parameters, from distances measured by cosmic gravitational wave sirens requires sufficient allowance for the dark energy evolution. We demonstrate how model independent statistical methods, specifically Gaussian process regression, can remove bias in the reconstruction of H(z), and can be combined model independently with supernova distances.Item Open Access Deep decarbonisation and growth: challenges and prospects(National Research University “Higher School of Economics” Moscow, Russia. International Scientific and University Conference. "Climate Change and CO2 Emission Reduction" 12-13 July, 2017, 2017-07-12) Safonov, GeorgyItem Open Access Developments in Cosmic Growth and Gravitation [Article](NURIS; Energetic Cosmos Laboratory, 2019-04-23) Linder, Eric V.Cosmic surveys of large scale structure have imaged hundreds of millions of galaxies and mapped the 3D positions of over a million. Surveys starting over the next few years will increase these numbers more than tenfold. Simultaneously, developments in extracting information on dark energy, dark matter, neutrinos, and gravity on cosmic scales have advanced greatly, with many important works from Asian institutions.Item Open Access EDUCATION FOR SUSTAINABLE DEVELOPMENT(UNIVERSITY OF DONJA GORICA, MONTENEGRO. International Scientific and University Conference. "Climate Change and CO2 Emission Reduction" 12-13 July, 2017. Astana. Kazakhstan., 2017-07) Vukotic, VeselinItem Open Access ELECTRIFYING AFRICA(International Scientific and University Conference. "Climate Change and CO2 Emission Reduction" 12-13 July, 2017, 2017-07) Andrieu, PriscilliaItem 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.