Viktor A. Klimenko

Dr. Viktor A. Klimenko


Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

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

Representative Publications

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6 July 2022 in Coatings
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Journal Article
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EGElena Glazkova
Elena Glazkova
OBOlga Vladimirovna Bakina
Olga Vladimirovna Bakina
NRNikolay Rodkevich
Nikolay Rodkevich
AMAndrey Mosunov
Andrey Mosunov
Maxim EvstigneevMaxim Evstigneev
Maxim Evstigneev
MLMarat I. Lerner
Marat I. Lerner
We have prepared a composite thin coating by incorporation of CuFe2O4/Cu2O/CuO nanoparticles in polymethyl methacrylate (PMMA) matrix by using the solution casting method. The electrical explosion of two twisted wires (EETW) was used to obtain multicomponent CuFe2O4/Cu2O/CuO nanoparticles with an average particle size of 20–70 nm. The microscopic studies showed that the nanoparticles in the composite coatings are evenly distributed. However, nanoparticles are strongly agglomerated as the powder concentration in the coating increases to 5 wt.% and 10 wt.%, as the size of particle agglomerates increases to 50 and 100 μm, respectively. Therefore, nanoparticles were pre-treated with ultrasound when introduced into the PMMA matrix. The thermal stability of the composite coating does not change with the introduction of CuFe2O4/Cu2O/CuO nanoparticles in the amount of 5 wt.%. The inclusion of nanoparticles in the PMMA matrix significantly enhances its antibacterial activity. The addition of 5 wt.% nanoparticles inhibited the growth of E. coli by 100% and the growth of MRSA by 99.94% compared to pure PMMA already after 3 h of exposure of bacteria on the surface of the composites. This research provides an easy-to-manufacture and cost-efficient method for producing a CuFe2O4/Cu2O/CuO/PMMA composite coating with a broad application as an antibacterial material.

23 November 2018 in Materials
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Journal Article
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VPVladimir Promakhov
Vladimir Promakhov
AZAlexander Zhukov
Alexander Zhukov
YDYana Dubkova
Yana Dubkova
IZIlya Zhukov
Ilya Zhukov
SKSergey Kovalchuk
Sergey Kovalchuk
NSNadezhda Savkina
Nadezhda Savkina
This investigation focused on obtaining samples from ceramic composite materials, based on the ZrO2–20%Al2O3 system, using the additive layer-by-layer fusion technology for thermoplastic systems. The structure and phase composition of the initial powders were studied, experimental samples were produced, and the structure and properties of the experimental samples that were obtained using additive technologies were analysed. The measured static bending strength of the samples was 450 ± 70 MPa, microhardness was 14 GPa, and the elasticity modulus was 280 ± 25 GPa. The strength of these samples are slightly inferior to that of similar materials, obtained using Ceramic Injection Molding technology because our samples were characterised by the residual porosity of about 15%.

17 June 2020 in Materials
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Journal Article
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RMRuslan Mendagaliyev
Ruslan Mendagaliyev
Olga Klimova-KorsmikOlga Klimova-Korsmik
Olga Klimova-Korsmik
VPVladimir Promakhov
Vladimir Promakhov
NSNikita Schulz
Nikita Schulz
AZAlexander Zhukov
Alexander Zhukov
AOAndrey Olisov
Andrey Olisov
The urgency of heat treatment of samples of maraging steel obtained by direct laser deposition from steel powder 06Cr15Ni4CuMo is considered. The structural features and properties of 06Cr15Ni4CuMo steel samples after direct laser deposition and heat treatment are studied. The work is devoted to research into the influence of thermal processing on the formation of structure and the mechanical properties of deposit samples. Features of formation of microstructural components by means of optical microscopy are investigated. Tests for tension and impact toughness are conducted. As a result, it was established that the material obtained by the direct laser deposition method in its initial state significantly exceeds the strength characteristics of heat treatment castings of similar chemical composition, but is inferior to it in terms of impact toughness and relative elongation. The increase in relative elongation and impact toughness up to the level of cast material in the deposit samples is achieved at the subsequent heat treatment, which leads to the formation of the structure of tempered martensite and reduction in its content at two-stage tempering in the structure of the metal. The strength of the material is also reduced to the level of cast metal.

9 March 2021 in Applied Sciences
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Journal Article
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VPVladimir Promakhov
Vladimir Promakhov
AMAlexey Matveev
Alexey Matveev
NSNikita Schulz
Nikita Schulz
MGMikhail Grigoriev
Mikhail Grigoriev
AOAndrei Olisov
Andrei Olisov
VKViktor A. Klimenko
Viktor A. Klimenko
Currently, metal–matrix composite materials are some of the most promising types of materials, and they combine the advantages of a metal matrix and reinforcing particles/fibres. Within the framework of this article, the high-temperature synthesis of metal–matrix composite materials based on the (Ni-Ti)-TiB2 system was studied. The selected approaches make it possible to obtain composite materials of various compositions without contamination and with a high degree of energy efficiency during production processes. Combustion processes in the samples of a 63.5 wt.% NiB + 36.5 wt.% Ti mixture and the phase composition and structure of the synthesis products were researched. It has been established that the synthesis process in the samples proceeds via the spin combustion mechanism. It has been shown that self-propagating high-temperature synthesis (SHS) powder particles have a composite structure and consist of a Ni-Ti matrix and TiB2 reinforcement inclusions that are uniformly distributed inside it. The inclusion size lies in the range between 0.1 and 4 µm, and the average particle size is 0.57 µm. The obtained metal-matrix composite materials can be used in additive manufacturing technologies as ligatures for heat-resistant alloys, as well as for the synthesis of composites using traditional methods of powder metallurgy.

10 September 2019 in Russian Physics Journal
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Journal Article
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VPVladimir Promakhov
Vladimir Promakhov
AZAlexander Zhukov
Alexander Zhukov
AVAlexander Vorozhtsov
Alexander Vorozhtsov
NSN. A. Schults
N. A. Schults
SKSergey Kovalchuk
Sergey Kovalchuk
VKViktor A. Klimenko
Viktor A. Klimenko

30 March 2023 in RUDN Journal of Psychology and Pedagogics
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Journal Article
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NVNikolay Veraksa
Nikolay Veraksa
MAMargarita S. Aslanova
Margarita S. Aslanova
KTKristina Tarasova
Kristina Tarasova
VKViktor A. Klimenko
Viktor A. Klimenko
Cognitive flexibility is considered a trait of human cognition that helps people adapt to new and changing environments by activating cognitive resources; it develops mainly at preschool age, being a predictor of children's future social and academic successes, which emphasizes the importance of diagnosing its formation. The present study is intended to assess the diagnostic capabilities of the digital version of the Dimensional Change Card Sort technique by P.D. Zelazo aimed at diagnosing the cognitive flexibility of preschoolers, compared with the traditional blank version. The digital version of the technique was tested on a sample of 55 children attending two senior kindergarten groups (57.1% of boys) aged 5 to 6 years (M = 64.03, SD = 2.14). An intra-individual scheme with the division of the subjects into two groups was applied. The first group was initially tested using the blank technique, and a month later using the digital one. The second group, on the contrary, was first tested using the digital technique and, a month later, using the blank one. Thus, the transfer effect was controlled. Sufficient indicators of reliability and consistency of the results of both measurements were obtained for the blank and digital versions of technique. No statistically significant differences were found between the mean values of the same indicators measured by digital and blank techniques different methods (Student’s t -test for paired samples). The results of the study show that the digital version of the Dimensional Change Card Sort technique has high indicators of validity and reliability and can be used in diagnostic work. However, these results indicate that the digitalization of techniques cannot always be reduced to a simple translation of them into the form of a software product, and requires additional research when adapting them.