Natalia Karakchieva

Dr. Natalia Karakchieva

Tomsk State University (Tomsk, Russia)
orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 February 2016 in International Journal of Hydrogen Energy
Verified
Journal Article
Closed access
DLDenis Leybo
Denis Leybo
ABAnar N. Baiguzhina
Anar N. Baiguzhina
Dmitry S. MuratovDmitry S. Muratov
Dmitry S. Muratov
DADmitry I. Arkhipov
Dmitry I. Arkhipov
EKEvgeny Kolesnikov
Evgeny Kolesnikov
Denis KuznetsovDenis Kuznetsov
Denis Kuznetsov

1 December 2017 in Chemical Engineering Journal
Verified
Journal Article
Closed access
IKI.A. Kurzina
I.A. Kurzina
SRS.I. Reshetnikov
S.I. Reshetnikov
Natalia KarakchievaNatalia Karakchieva
Natalia Karakchieva
LKL.N. Kurina
L.N. Kurina

3 August 2017 in Metals
Verified
Journal Article
Open access
PDF file
NRNina Radishevskaya
Nina Radishevskaya
OLOlga Lepakova
Olga Lepakova
Natalia KarakchievaNatalia Karakchieva
Natalia Karakchieva
ANAnastasiya Nazarova
Anastasiya Nazarova
NANikolai Afanasiev
Nikolai Afanasiev
Alexander A. GusevAlexander A. Gusev
Alexander A. Gusev
Metal borides are widely used as heat-insulating materials, however, the range of their application in high-temperature conditions with oxidative medium is significantly restricted. To improve the thermal stability of structural materials based on titanium boride, and to prevent the growth of TiB2 crystals, additives based on alumina-magnesia spinel with chemical resistant and refractory properties have been used. The aim of this work is to study the structure of TiB2 with alumina-magnesia spinel additives obtained by self-propagating high-temperature synthesis (SHS). TiB2 structure with uniform fine-grained distribution was obtained in an MgAl2O4 matrix. The material composition was confirmed by X-ray diffraction analysis (DRON-3M, filtered Со kα-emission), FTIR spectroscopy (Thermo Electron Nicolet 5700, within the range of 1300–400 cm−1), and scanning electron microscopy (Philips SEM 515). The obtained material represents a composite, where the particles of TiB2 with a size of 5 µm are uniformly distributed in the alloy of alumina-magnesia spinel.

29 June 2020 in Metals
Verified
Journal Article
Open access
PDF file
Akbayan BelgibayevaAkbayan Belgibayeva
Akbayan Belgibayeva
YAYuri Abzaev
Yuri Abzaev
Natalia KarakchievaNatalia Karakchieva
Natalia Karakchieva
RERakhmetulla Erkassov
Rakhmetulla Erkassov
VSVictor Sachkov
Victor Sachkov
Irina KurzinaIrina Kurzina
Irina Kurzina
The structural state and the quantitative phase analysis of the TiAl system, alloyed with rare-earth metals synthesized using hydride technology, were studied in this work. Using the Rietveld method, the content of the major phases in the initial system Ti(50 at.%)–Al(50 at.%), as well as Ti(49 at.%)–Al(49 at.%), with alloying additions Ta, Y and Dy having a high accuracy was determined. The methods of scanning electron microscopy, transmission electron microscope and X-ray spectral microanalysis of the local areas of the structure for studying the distribution of alloying elements were used. The energies of lattices of separate phases were also determined after the full-profile specification. All the lattices of the identified structures (about 30) turned out to be stable. It was established that in the Ti(49 at.%)–Al(49 at.%) systems under study with alloying additions of metals Ta, Y and Dy, there were intermetallides composed of AlTi3, TiAl in the hexagonal, tetragonal and triclinic units. It is known that after microalloying alloys by Y and Dy metals, the mass fraction of TiAl phases increases significantly (>70%).

20 October 2019 in Minerals
Verified
Journal Article
Open access
PDF file
EDElena Daibova
Elena Daibova
ILInna V. Lushchaeva
Inna V. Lushchaeva
VSVictor Sachkov
Victor Sachkov
Natalia KarakchievaNatalia Karakchieva
Natalia Karakchieva
VOVladislav Orlov
Vladislav Orlov
NSNatalya I. Sodnam
Natalya I. Sodnam
The influence of the environment and bacterial cultures on the degree of gold leaching from Au-containing raw materials of different compositions, origins, and with different contents of gold, selected in the Ural Federal District (Russia), was determined. The leaching degree was determined according to the change of the gold concentration in the ore by means of mass-spectrometry with inductively-coupled plasma. It was demonstrated that the degree of Au bioleaching from carbonaceous-argillaceous slates, containing 2.17 g/t of gold, and from pyritic technogenic raw materials, containing 1.15 g/t, when holding them in peptone water and Leten medium reached 92.17% and 87.83%, respectively.

6 May 2015 in Journal of Nanoparticle Research
Verified
Journal Article
Closed access
PDF file
AGAnna Godymchuk
Anna Godymchuk
EKElizaveta Karepina
Elizaveta Karepina
EYElena Yunda
Elena Yunda
IBIrina Bozhko
Irina Bozhko
GLGalina Lyamina
Galina Lyamina
Natalia KarakchievaNatalia Karakchieva
Natalia Karakchieva