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Bekturganov N.S.,National scientific technological holding Parasat | Bissengaliyeva M.R.,Institute of problems of complex development of mineral resources | Gogol D.B.,Institute of problems of complex development of mineral resources
Eurasian Chemico-Technological Journal | Year: 2013

A zinc silicate is in a great demand in modern technology due to its fluorescent, optical and catalytic properties. However, its thermodynamic properties have been studied not sufficiently, and they are focused primarily in the geological and geochemical sciences. An attempt to calculate for a natural zinc silicate willemite (Zn2SiO4) its crystal structure, vibrational properties, phonon states and thermodynamic functions was made in this work. The force constants and vibrational states of the mineral have been calculated in this paper by a combination of the methods of quantum-chemical calculations (MOPAC) with semi-empirical method PM5 and the theory of crystal lattice dynamics (LADY program) with valence force field potential model. Theoretical infrared and Raman spectra of the mineral were simulated on the base of calculated vibrational states. A good agreement between the experimental and theoretical vibrational spectra of the mineral has been achieved. After that the Brillouin zone scanning of the mineral crystal structure was made which is necessary to obtain the information about the whole phonon spectrum in the lattice. Density-of-state function was determined by summation over all the phonon states and used for determination of energetics of the crystal. The values of the basic thermodynamic functions for willemite (heat capacity, entropy and change of enthalpy) over the range of (10-298.15) K have been obtained. The standard values of these functions are: Cp(298.15) = 126 J/(mol•K) (PM5 calculation) and 122.5 J/(mol•K) (LADY calculation), So(298.15) = 133.4 J/(mol•K) (LADY calculation), and Ho(298.15)-Ho(0) = 21494 J/mol (PM5 calculation). The calculated heat capacity values are in satisfactory agreement with known experimental data. © 2013 Al-Farabi Kazakh National University.


Bissengaliyeva M.R.,Institute of Problems of Complex Development of Mineral Resources | Bekturganov N.S.,National Scientific Technological Holding Parasat | Gogol D.B.,Institute of Problems of Complex Development of Mineral Resources | Knyazev A.V.,Novgorod State University | And 4 more authors.
Materials Chemistry and Physics | Year: 2015

Compounds of the ternary oxides class with formulae MgLa2MoO7 and CaLa2MoO7 were synthesized by the citrate method. According to the SEM and X-ray analysis data the samples are referred to pyrochlore with a tetragonal (MgLa2MoO7) and monoclinic (CaLa2MoO7) crystal lattice. At the temperature of 900 °C the compound CaLa2MoO7 is subjected to phase transition from the monoclinic crystal system to the cubic one. According to the differential thermal analysis data, this transition occurs through the intermediate states characterized by non-monotonic changes of lattice parameters of the unit cell. In general, the compounds are characterized by minor structural distortions compared with the cubic structure of pyrochlore. © 2015 Elsevier B.V. All rights reserved.


Khassen B.,Institute of Problems of Complex Development of Mineral Resources | Baltynova N.,Institute of Problems of Complex Development of Mineral Resources | Dakhno L.,Karaganda State Technical University
International Journal of Mineral Processing | Year: 2014

The results of investigation of sintering and magnetic beneficiation of brown iron ore concentrate are presented. The investigations are based on using a possibility of redistribution of phosphorus from the ore constituents into slag-forming ones in the process of sinter roasting. © 2013 Elsevier B.V.


Bissengaliyeva M.R.,Institute of Problems of Complex Development of Mineral Resources | Gogol D.B.,Institute of Problems of Complex Development of Mineral Resources | Taimassova S.T.,Institute of Problems of Complex Development of Mineral Resources | Bekturganov N.S.,Science National Scientific technological Holding Parasat | Bort A.T.,Science Tsentrkaznedra
Thermochimica Acta | Year: 2013

The heat capacity of natural strontium sulfate - mineral celestine - has been measured over the range of 5.320 K by the method of adiabatic calorimetry and its thermodynamic functions have been determined. The methods of X-ray phase analysis, Raman spectroscopy and electron probe microanalysis have confirmed the adequacy of the sample to mineral celestine. The standard values of thermodynamic functions were: C° p(298.15) = 100.30 ± 0.11 J mol-1 K-1, S° 298.15 = 123.44 ± 0.28 J mol-1 K-1 and ΔH° 298.15 = 18, 406 ± 33 J mol -1. The heat capacity and thermodynamic functions of celestine have also been calculated by means of methods of semi-empirical quantum-chemical calculation and the theory of crystal lattice dynamics. © 2013 Elsevier B.V.


Bissengaliyeva M.R.,Institute of Problems of Complex Development of Mineral Resources | Knyazev A.V.,Novgorod State University | Bekturganov N.S.,National Scientific and Technological Holding Parasat | Gogol D.B.,Institute of Problems of Complex Development of Mineral Resources | And 4 more authors.
Journal of the American Ceramic Society | Year: 2013

A new sample of triple oxides - barium-thulium bismuthate Ba 2TmBiO6 with perovskite structure - has been synthesized by ceramic technology. The unit cell parameters of the sample and the coefficients of thermal expansion have been determined by the method of X-ray analysis. Thermal properties of the sample have been studied by DTA over the temperature range of 293-1473 K. The heat capacity of the compound has been measured over the range of 5-320 K by vacuum adiabatic calorimetry. Thermodynamic functions of the compound have been determined based on the heat capacity data. © 2013 The American Ceramic Society.


Bissengaliyeva M.,Institute of Problems of Complex Development of Mineral Resources | Ogorodova L.,Moscow State University | Vigasina M.,Moscow State University | Mel'Chakova L.,Moscow State University | And 3 more authors.
Journal of Chemical Thermodynamics | Year: 2016

This paper presents the results of the thermochemical study of hydrous copper sulfate CuSO4·5H2O performed on a high-temperature heat-flux Tian-Calvet microcalorimeter. The samples of two natural chalcanthite (Kosmurun ore deposit, Kazakhstan, and Lavrion deposit, Greece) and synthetic hydrous copper sulfate (blue vitriol) were characterized by X-ray microprobe analysis, X-ray powder diffraction, thermal analysis, FTIR and Raman spectroscopy. The enthalpy of dehydration at T = 298.15 K was measured, and the standard molar enthalpies of formation from the elements were determined by the melt solution calorimetry in accordance with Hess's law. The values of ΔfHm0 (T = 298.15 K) were found to be -(2267.2 ± 4.1) kJ.mol-1 for natural chalcanthite and -(2272.6 ± 6.0) kJ·mol-1 for synthetic hydrous copper sulfate (blue vitriol). © 2015 Published by Elsevier Ltd.


Bissengaliyeva M.R.,Institute of Problems of Complex Development of Mineral Resources | Taimassova S.T.,Institute of Problems of Complex Development of Mineral Resources | Zhakupov R.M.,Institute of Problems of Complex Development of Mineral Resources | Zhakupov R.M.,Lobachevsky State University of Nizhni Novgorod | And 2 more authors.
Journal of Thermal Analysis and Calorimetry | Year: 2016

The temperature dependence of the heat capacity of pyrochlore-like compounds CaLa2MoO7 and MgLa2MoO7 has been investigated over the range of 4.4–320 K by adiabatic calorimetry. The main thermodynamic functions and fractal properties of the compounds over the range of 5–320 K have been determined based on the experimental data. We have revealed the heat capacity anomaly in the sample CaLa2MoO7 in the area below 10 K. Standard thermodynamic functions at T = 298.15 K are: for CaLa2MoO7Cp,m(298.15) = 222.1 ± 0.4 J mol−1K−1, Sm(298.15) = 246.0 ± 0.8 J mol−1K−1, Hm(298.15)−Hm(0) = 39.20 ± 0.10 kJ mol−1; for MgLa2MoO7Cp,m(298.15) = 216.6 ± 0.3 J mol−1K−1, Sm(298.15) = 231.1 ± 0.6 J mol−1K−1, Hm(298.15) − Hm(0) = 37.09 ± 0.08 kJ mol−1. © 2016 Akadémiai Kiadó, Budapest, Hungary

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