bluuebunny/crossref_metadata_2025 huggingface dataset:
Ecological and economic assessment of the effectiveness of technical and technological solutions for resource-saving technologies for cultivating grain crops in Siberia
Authors:   Siberian Federal Scientific Center for Agricultural and Biological Technologies of the Russian Academy of Sciences, Krasnoobsk, Novosibirsk region, Russia, Utenkov Gennady L. , Utenkova Tatiana I. ,   Siberian Federal Scientific Center for Agricultural and Biological Technologies of the Russian Academy of Sciences, Krasnoobsk, Novosibirsk region, Russia, Koteev Sandzhi V. ,   VIAPI named after A.A. Nikonov is a branch of the Federal Scientific Center for Agrarian Economics and Social Development of Rural Areas– VNIIESH, Moscow, Russia
Published: September 2024

The article analyzes and evaluates the effectiveness of grain cultivation in Siberia. The high energy intensity and poor execution of technological processes leading to their low efficiency and disturbance of the ecological balance have been revealed. It is necessary to improve the methodological approach and develop new mathematical models for the ecological and economic assessment of technological and technical solutions that reduce energy intensity as the main indicator with the predominant use of extensive technologies and reduce the anthropogenic load on the soil. Methodological and technical and technological solutions are proposed to assess the anthropogenic impact on the environment and reduce material costs in resource-saving technologies for the cultivation of grain crops in Siberia. The main economic indicators of the efficiency of cultivation of agricultural land are considered. The conditions of yield growth as a random variable and the main indicator of agricultural efficiency are shown. The rational structure of the three levels of technology intensity recommended for the conditions of the SFO is determined, and the model of mathematical expectation of full expenditures is substantiated. The functions of useful work and time losses are determined; the ration structure of technological processes of basic tillage is proposed. The prospects of using flexible tillage complexes are considered. For each specific case, an algorithm for the ecological and economic assessment of technological and technical solutions is proposed, taking into account the main economic indicators, including energy supply and the quality of the technological processes performed. To reduce energy intensity and improve the environmental situation, a rational structure of recommended levels of technology intensity for the conditions of the Siberian Federal District with an appropriate set of technical support for basic tillage processes is proposed.
Innovative management accounting methods to ensure the sustainability of agricultural and processing enterprises
Authors:   D.N. Pryanishnikov Institute of Agrochemistry, Moscow, Russia, Zhdanov Vasilii Yu. , Sidorova Tatiana A. ,   D.N. Pryanishnikov Institute of Agrochemistry, Moscow, Russia, Makarova Natalia V. ,   D.N. Pryanishnikov Institute of Agrochemistry, Moscow, Russia
Published: September 2024

The article identifies innovative management accounting methods that can be integrated into the strategies of agricultural enterprises in order to ensure their sustainable development. To identify traditional and innovative methods of management accounting, an analysis of foreign literature on management accounting was conducted. The definition of innovative management accounting methods in agricultural organizations that focus on the strategic development of the organization, as opposed to traditional methods that focus on past data, is formulated. During the analysis, six innovative management accounting methods were identified: budgeting based on activities; product life cycle cost; general quality management; target costs; kaizen calculation and cost analysis, which can be used to increase the sustainability of agricultural organizations. The principles of innovative management accounting methods for their implementation in the strategies of agricultural organizations are defined.
Analysis of the current state of food security in a region
Authors:   FSBI HE «Lugansk State Agrarian University named after K.E. Voroshilov», Lugansk, Shevchenko Maria N. , Ivannikov Andrey S. ,   FSBI HE «Lugansk State Agrarian University named after K.E. Voroshilov», Lugansk, Ivanyuk Irina V. ,   FSBI HE «Lugansk State University named after V. Dahl», Lugansk
Published: September 2024

The article discusses the prerequisites for the formation of food security in the region – Lugansk People’s Republic. An analysis of the current state of food security in the region and a factor analysis of the level of food consumption by the population was carried out, the results of which made it possible to establish the discrepancy between the production volumes of the main types of agricultural and food products and the rational norms of food consumption, both of crop and livestock origin. It is proved that the predominant negative impact on the level of food consumption by the population is caused by the factor of insufficient production of basic types of agricultural products. Based on the results of the analysis of self-sufficiency, a discrepancy between the actual volumes of food production and consumption standards was revealed. A conclusion is drawn about the strategic importance and directions of development of the agricultural industry based on effective public policy.
Study of the rational functioning and development of food industry enterprises – potential participants of the cluster at the fat and oil subcomplex of a region
Authors:   Federal State Budgetary Research Institution Federal Scientific Centre «Saratov Scientific Centre of the Russian Academy of Sciences», Saratov, Russia, Leksina Anna A.
Published: September 2024

Numerous scientific studies of clusters in the agricultural economy are devoted to assessing the general trends in the indicators of individual industries, methodological approaches to creating integrated structures within them. But the issues of applying a systematic approach to the study of regional processes occurring in a group of industry enterprises within one product subcomplex remain insufficiently developed. The purpose of the work is to select, form into a system and test economic and statistical indicators that allow assessing the rationality of functioning and the level of development of food industry enterprises, potentially or actually forming a specialized cluster in the oil and fat subcomplex of the region. Indicators for analyzing trends in the field of processing, rational functioning and development processes for oil extraction plants and a fat plant are proposed. Analysis of structural shifts, the study of consolidated natural and financial indicators of production and economic activity made it possible to determine the trends occurring in the industry. By means of consolidated specific and relative economic indicators, the rationality of the functioning of enterprises of the subcomplex is assessed. Conclusions about development processes were made based on quantitative indicators of qualitative changes, innovative areas of improvement, and involvement in government development programs. The analysis of diverse indicators characterizing the current state of rationality and the pace of business development, illustrating the transformation of the economy of enterprises in connection with the scale-up of production, is presented. The proposed research system was tested on official statistical materials recorded in the annual accounting reports of enterprises in the Saratov region. The practical significance of the work lies in the use of the results to make decisions on the rationalization of production and economic processes and development strategies. The author’s idea seems to be universal and can be applied in the study of economic processes and development of cluster participants in other subcomplexes of the national economy.
Integration of small and medium-sized farms with agricultural holdings
Authors:   VIAPI named after A.A. Nikonov is a branch of the Federal Scientific Center for Agrarian Economics and Social Development of Rural Areas – VNIIESH, Moscow, Russia, Goncharov Vladimir D. , Kibirov Khetag G. ,   VIAPI named after A.A. Nikonov is a branch of the Federal Scientific Center for Agrarian Economics and Social Development of Rural Areas – VNIIESH, Moscow, Russia
Published: September 2024

The article provides an assessment of the current level of production of agricultural products of various categories of farms. The objective necessity of integrating agricultural holdings with farms, including individual entrepreneurs, as well as personal subsidiary farms, has been proved. This will not only increase the volume of food resources, but also preserve rural areas.
The regulatory framework for regulating the activities of peasant (farm) farms in Russia
Authors:   A.A. Nikonov VIAPI is a branch of the Federal Scientific Center for Agrarian Economics and Social Development of Rural Areas– VNIIESH, Moscow, Russia, Borodin Konstantin G. , Frolova Elena Yu. ,   A.A. Nikonov VIAPI is a branch of the Federal Scientific Center for Agrarian Economics and Social Development of Rural Areas– VNIIESH, Moscow, Russia, Zadorozhnaya Elena A. ,   A.A. Nikonov VIAPI is a branch of the Federal Scientific Center for Agrarian Economics and Social Development of Rural Areas– VNIIESH, Moscow, Russia
Published: September 2024

The agro-food complex of the Russian Federation has become one of the powerful drivers of the country’s economic development, providing an increasingly high level of food security. The experience of the formation of the agricultural sector of the European Union, dating back more than 70 years, shows that the leading role in its creation was initially played by the adopted legal documents, in particular, articles 38-47 of the Treaty of Rome of 1958 («Treaty Establishing the European Economic Community»). A skillful combination of administrative and economic regulation measures and constant adjustment of the legal framework have ensured the effective functioning of European agricultural producers, among which farms have a special status. In the Russian Federation, the role of farmers as producers of agricultural products is also growing from year to year. This paper examines the historical and modern aspects of the formation of the Russian regulatory framework for the functioning of peasant (farmer) farms as a special group of agricultural producers that emerged as a result of the reforms of the 90s of the last century. The article highlights the dual nature of peasant (farmer) farms as commodity producers and as a social group uniting rural residents interested in its development and evaluates the existing tools for supporting farmers and their effectiveness.
Trade cooperation between Russia and Turkey in the agricultural sector of the economy
Authors:   Institute of Economics of the Russian Academy of Sciences, Moscow, Russia, Siparo Konstantin A.
Published: September 2024

The article highlights the dynamics of development of Turkey’s agricultural sector, relations with partner countries, in particular with Russia. Trade turnover, support and interest from various external partners are examined. The influence of Russian products on Turkish markets is highlighted, and the nomenclature is detailed. The indicators of recent years have been studied, patterns in mutual trade turnover have been revealed. Based on the data obtained, conclusions are drawn about the prospects for further trade cooperation between Russia and Turkey in the agricultural sector.
Investment opportunities for the development of agriculture in Yakutia
Authors:   Arctic State Agrotechnological University, Yakutsk, Russia, Efremov Artem K.
Published: September 2024

The article discusses potential investment opportunities in the agriculture of Yakutia. The purpose of the study is to analyze the current state and prospects of agricultural development in the Republic of Sakha (Yakutia) with an emphasis on identifying potential investment opportunities. The dynamics of the cattle population was studied, the analysis was performed and the factors influencing the development of cattle breeding were determined. Various sources of investment are being investigated, including public financing, private investment and foreign investment. The article also provides recommendations for improving the investment attractiveness of agriculture in Yakutia. Measures and approaches to improve investment policy are proposed to improve the situation in the agricultural sector, as well as examples of potentially successful areas of investment (primarily in animal husbandry) applicable in Yakutia, taking into account risk factors such as natural and climatic features, market conditions, etc.
Autoimmune Hypothyroidism Associated with Helicobacter Pylori Infection
Authors: AL-jumaili Miqdam M Obaid
Published: September 2024

Objective: The study aimed to investigate the correlation between Helicobacter pylori (H. pylori) and thyroid autoimmunity. Material and Methods: To demonstrate the possible correlation between H. pylori infection and autoimmune hypothyroidism, 200 individuals were enrolled in this research (100 patients with active H. pylori infection and 100 healthy controls). All of them were tested for serum levels of thyroid hormones, thyroid stimulating hormone (TSH), and autoantibodies, as well as Helicobacter pylori-Immunoglobulin G (H. pylori-IgG) and cytotoxin-associated gene A-Immunoglobulin G (cagA-IgG) antibodies. Results: The study found that H. pylori infection was associated with higher levels of TSH, thyroperoxidase and thyroglobulin (TPO and TG) (p-value<0.000, 0.001 and 0.006, respectively) and a significant decrease in the levels of free-thyroid hormone (FT3 and FT4) (p-values=0.008 and 0.007 respectively) in patients compared with the control group. Moreover, using Pearson’s correlation tests, significant proportional correlations were found between H. pylori IgG and TSH (r=0.302, p-value=0.001), and a significant negative correlation was found between anti-H. pylori-IgG and with FT3 and FT4 (r=-0.261, p-value=0.003 and r=-0.260, p-value=0.003, respectively). Moreover, Spearman’s correlation results showed that H. pylori IgG was positively linked to TPO (r=0.531, p-value<0.001) and TG (r=0.320, p-value=0.001). Conclusion: The current investigation found that H. pylori infection was linked to higher concentrations of thyroid autoantibody and TSH and lower levels of thyroid hormones, suggesting that the bacterium may play a role in the development of subclinical autoimmune hypothyroidism.
Study of application of bioclimatic architecture strategy at Citraland Residential House in Palu City
Authors: Salenda Hariyadi , Winarta A , Khaerunnisa Khaerunnisa , Abidin A
Published: September 2024

Palu City has a fairly hot air temperature, very high intensity of solar radiation, quite high rainfall, and a fairly large wind speed. When reviewing the climatic conditions of Palu City above, the planners in this case the Citraland housing architect team should be able to apply a bioclimatic architecture strategy to be able to respond to the climatic conditions of the city of Palu. Based on this background, it is necessary to conduct a research study on the application of bioclimatic architecture strategies in Citraland's residences. This study uses a rationalistic approach with an exploratory method. Research shows that Citraland Residence has implemented a bioclimatic architectural strategy in several ways, namely the use of shading or shadow effects in the form of roof canopy, eaves, and lattice made of wood, and protective plants, as well as the use of insulating materials such as natural stone affixed to the outer walls. residential home. In addition, the layout of the residence also plays a role in the flow of air circulation to the maximum. Then the strategy of making wind-catching rooms and the use of glass materials on several sides of the building which acts as a place to enter sunlight into the house
Advancements in precast concrete sandwich panels for load bearing structures
Authors: Kumar Pushpender , Nighot Nikhil Sanjay , Kumar Rajesh , Sharma Surabhi , Kirgiz MS , Goyal Arpit
Published: September 2024

Concrete sandwich panels consist of two concrete layers separated by an insulating foam core, offering thermal insulation, structural strength, and fire resistance. This study investigates sustainable precast concrete sandwich panels made with industrial waste materials like limestone slurry, quarry waste, and basalt fiber as shear connectors. The research evaluates the flexural and axial strength behavior of these panels and explores strategies to improve their structural performance. The panels were fabricated with outer concrete layers, an expanded polystyrene (EPS) insulation core, and basalt fiber connectors. Flexural tests using four-point bending and axial compression tests were conducted on panels with varying concrete layer thicknesses and basalt fiber widths. Findings revealed panels with thicker outer concrete layers (35mm) and wider basalt fiber connectors (11.5mm) exhibited higher cracking loads, load-hardening behavior, and increased ductility compared to thinner layers and narrower connectors. The axial test showed premature failure at the top and bottom quarters. Thicker concrete layers and wider basalt fiber connectors enhanced crack control, load distribution, and ductile behavior under flexural loading. Strengthening measures like additional reinforcement, proper anchorage detailing, and increased shear reinforcement at the end regions are recommended to improve axial load-bearing capacity and prevent premature end failures.  The PCSP demonstrated up to 40% cost savings over commercial products while providing better thermal insulation than conventional brick masonry due to the EPS core. Overall, the study promotes developing sustainable, energy-efficient, and cost-effective load-bearing sandwich panel systems.
Enhanced data augmentation for predicting consumer churn rate with monetization and retention strategies: a pilot study
Authors: Geteloma Victor Ochuko , Aghware Fidelis Obukohwo , Adigwe Wilfred , Odiakaose Chukwufunaya Chris , Ashioba Nwanze Chukwudi , Okpor Margareth Dumebi , Ojugo Arnold Adimabua , Ejeh Patrick Ogholuwarami , Ako Rita Erhovwo , Ojei Emmanuel Obiajulu
Published: September 2024

Customer retention and monetization have since been the pillar of many successful firms and businesses as keeping an old customer is far more economical than gaining a new one – which, in turn, reduce customer churn rate. Previous studies have focused on the use of single heuristics as well as provisioned no retention strategy. To curb this, our study posits the use of the recen-cy-frequency-monetization framework as strategy for customer retention and monetization impacts. With dataset retrieved from Kaggle, and partitioned into train and test dataset/folds to ease model construction and training. Study adopt a tree-based Random Forest ensemble with synthetic minority oversampling technique edited nearest neighbor (SMOTEEN). Various benchmark models were trained to asssess how well each performs against our proposed ensemble. The application was tested using an application programming interface Flask and integrated using streamlit into a device. Our RF-ensemble resulted in a 0.9902 accuracy prior to applying SMOTEENN; while, LR, KNN, Naïve Bayes and SVM yielded an accuracy of 0.9219, 0.9435, 0.9508 and 0.9008 respectively. With SMOTEENN applied, our ensemble had an accuracy of 0.9919; while LR, KNN, Naïve Bayes, and SVM yielded an accuracy of 0.9805, 0.921, 0.9125, and 0.8145 respectively. RF has shown it can be implemented with SMOTEENN to yield enhanced prediction for customer churn prediction using Python
Stress-dependent Magnetization Processes in Co based Amorphous Microwires
Authors: Evstigneeva S. A. , Lutsenko O. , Ganzhina T. Y. , Miroshkina V. V. , Yudanov N. A. , Nemirovich M. A. , Panina L. V.
Published: September 2024

Soft magnetic materials with high magnetic susceptibility are sensitive to changing magnetic fields and generate electrical voltage signals whose spectra contain higher harmonics. Magnetic susceptibility and saturation field are largely determined by magnetoelastic interactions in amorphous ferromagnets, respectively, the amplitudes of higher harmonics should depend on external mechanical stresses. In this work, we study the processes of magnetization reversal in amorphous microwires of two compositions: Co71Fe5B11Si10Cr3 and Co66.6Fe4.28B11.51Si14.48Ni1.44Mo1.69 under the action of external tensile stresses. For the first composition, mechanical stresses exceeding a certain limit (more than 350 MPa) lead to the transformation of the magnetic hysteresis from a bistable type to an inclined one. In this case, a sharp change of the harmonic spectrum is observed. In microwires of the second composition with an initially inclined loop, external stresses cause a monotonous increase in the slope of the hysteresis loop (a decrease in susceptibility). In this case, the amplitudes of higher harmonics change significantly at low stresses, less than 100 MPa. The results were obtained by remagnetization of microwire samples using a system of flat coils, which demonstrates the potential of using these materials as wireless sensors of mechanical stresses with remote reading.
Transverse magneto-optical Kerr effect enhancement in si–ni nanogratings by mie and surface lattice resonances
Authors: Mamian K. A. , Frolov A. Yu. , Popov V. V. , Fedyanin A. A.
Published: September 2024

We demonstrate experimentally that a one-dimensional array of silicon nanowires periodically placed on a nickel substrate enhances the transverse magneto-optical Kerr effect (TMOKE) compared to a nickel film. The enhancement mechanism is associated with the excitation of two types of resonances: multipole Mie resonances in each nanowire and surface lattice resonances (SLRs) emerging from the periodic arrangement of the nanowires. The maximal TMOKE values reached up to 1.9 % and 2.6 % due to the excitation of SLR and a magnetic dipole resonance, respectively. When the SLR is excited, the spectral width of the TMOKE enhancement is narrower compared to the case of the magnetic dipole resonance.
Fabrication of submicron CoFeB/MgO/CoFeB magnetic tunnel junction using a resistive mask HSQ/PMMA
Authors: Fedotov I. A. , Pashen’kin I. Yu. , Skorokhodov E. V. , Gusev N. S.
Published: September 2024

The technology of manufacturing magnetic tunnel junctions based on CoFeB/MgO/CoFeB layers with characteristic lateral dimensions from 200 to 700 nm using a combination of HSQ/PMMA electronic resistors has been developed. To study the processes of magnetization reversal in the obtained samples, measurements of magnetoresistance curves were carried out. It is shown that, depending on the structure of the magnetically sensitive layer and the geometric parameters of the TMR contacts, elements with both vortex and quasi-homogeneous distribution of the magnetization of the free layer are realized. At the same time, in the latter, the width of the magnetization reversal front is from 2 to 6 Oe.
Magnetization processes features in the tapes of cobalt-based amorphous alloy
Authors: Skulkina N. A. , Nekrasov E. S. , Eremin Yu. D. , Kuznetsov N. V.
Published: September 2024

Studies of the amorphous cobalt-based soft magnetic alloy AMAG-172 (Co–Ni–Fe–Cr–Mn–Si–B) from different manufacturers have shown that in the as-quenched state there is nonuniformity of the magnetic characteristics, and therefore the level of internal stresses across the width of the tape produced by MSTATOR (Borovichi) significantly lower. However, similar to the tape produced by NIIMET (Kaluga), there is nonuniformity of the tape in thickness, which contributes to the formation of a bimodal field dependence of magnetic permeability.This may be a consequence of the non-uniform concentration along the width of the tape of hydrogen and oxygen atoms embedded in its surface during interaction with atmospheric vapor and the presence of temperature gradients during the manufacturing process. A stepwise shape of the initial sections of the magnetization curves in the region of the first maximum of magnetic permeability was discovered. The abrupt nature of the magnetization processes in the region of weak fields allows us to conclude that in the samples of tape produced by MSTATOR, the formation of the first maximum of the field dependence is associated with an independent magnetization reversal of the surface layer, while the main layer of the tape participates in the formation of the second maximum. The smoothed shape of the stepped initial section of the magnetization curve of samples produced by NIIMET corresponds to the gradual involvement of the main layer of the tape in the processes of magnetization and remagnetization. A comparison of the hysteresis loops of both parts of the tape, measured in the same magnetic field region, shows that the field shift of the hysteresis loops is associated with the interlayer interaction of the surface and volume of the tape, and the formation of asymmetric hysteresis loops occurs with the participation of the second layer with its gradual involvement in the processes of magnetization and magnetization reversal.
Contact potential difference in the absence of current through the sample in the quantum hall effect regime in InGaAs/InAlAs heterostructure
Authors: Gudina S. V. , Neverov V. N. , Turutkin K. V. , Vasil’evskii I. S. , Vinichenko A. N.
Published: September 2024

The paper presents experimental results of the appearance of voltage at potential contacts in the absence of an external current through the sample in the plateau region of the quantum Hall effect in a heterostructure with an InGaAs/InAlAs quantum well. The occurrence of voltage is associated with the non-equivalence of edge current in potential contact areas in a magnetic field in a system with a two-dimensional electron gas.
Study of minor Sc and Zr additions effect on silicon rich Al–Mg–Si aluminum alloy microstructure during Sc multistage thermal treatment
Authors: Aryshenskii E. V. , Lapshov М. А. , Rasposienko D. Y. , Konovalov S. V. , Drits A. M. , Makarov V. V.
Published: September 2024

The study addresses the effect of multistage thermal treatment on microstructure formation of Al–Mg–Si series alloy with scandium and zirconium additions in Mg/Si = 0.3 proportion. Basic alloy AlM–Si without Sc and Zr and them modification AlMg1SiZrSc were cast. AlMgSiScZr alloy multi-stage thermal treatment included the following 4 annealing stages –550 °C 8 h + 440 °C 8 h + 500 °C 0.5 h + 180 °C 5 h. For AlMg1Si alloy it was performed following 550 °C 8 h + 180 °C 5 h practice. AlMgSiScZr microstructure was examined using scanning (SEM) and transmission (TEM) microscopy both in as-cast state and after each stage of thermal treatment, for AlMg1Si – both in as-cast state and after final thermal treatment. Coarse intermetallic particles were examined using SEM, while fine particles were examined using TEM. Besides, microhardness values were measured after various thermal treatment stages. It was found out, that coarse intermetallic compounds of Fe2Mg7Si10Al18 type are formed in both alloys during as-cast structure cooling down with such compounds partial dissolution during further thermal treatment. At the same time particles, that can be attributed either to (AlSi)3ScZr or to AlSc2Si2τ-phase, occur in inter-grain boundary of alloys with scandium-zirconium additions. No traces of scandium solid solution discontinuous decomposition have been identified during ingot cooling down. Thermal treatment during 8 h at 550 °C 8 and 8 h at 440 °C results in formation of the phase, which can represent both AlSc2Si2 and Al5SiZr2. At the same time nanoparticles (AlSi)3ScZr do not form during this thermal treatment stage. Heating to 500 °C during 30 min interval allows complete dissolution of magnesium in supersaturated aluminum solid solution. During the final stage β’’ particles (Mg5Si6), representing the major type, form in both alloys; in these conditions scandium does not produce significant effect on their formation.
Capillary interaction of copper melt with dense and porous MAX phase (Cr, Mn)2AlC
Authors: Zhevnenko S. N. , Gorshenkov M. V.
Published: September 2024

In the present work, we experimentally studied the interaction of a pure copper melt with a dense MAX-phase (Cr, Mn)2AlC after sintering by the electric pulse plasma method and a porous phase obtained by pressing at room temperature. The porous phase (20 % porosity) absorbs molten copper at temperatures above 1200 °C; the kinetics of absorption was directly measured using high-speed thermal and video cameras. The experiments were carried out in a vacuum of 10–3 Pa. Studies using scanning electron microscopy, EDX spectral analysis and X-ray diffraction have shown that a chemical interaction of the MAX-phase with a copper melt occurs with the formation of a solution of aluminum and chromium in copper and the decomposition of the MAX-phase to chromium carbides (stable or metastable). The dense, sintered sample also actively interacts with the melt, although the contact angles exceed 100°. The difference between porous and dense samples lies in the kinetics of interaction. The results were compared with experiments on wetting the Cr2AlC MAX-phase with a Cu (0.8 at.% Cr) melt conducted earlier. The described experimental conditions and the results of determining chemical and phase changes in the process of capillary interaction indicate the possibility of creating a composite material with a submicron structure of chromium carbide impregnated with aluminum bronze.
Decomposition features and mechanical properties of aging Ti49Ni51 alloy with shape memory effects subjected to heat treatment
Authors: Kuranova N. N. , Makarov V. V. , Pushin V. G.
Published: September 2024

The features of the microstructure of the Ti–51 at.%Ni shape memory alloy have been studied after aging at various temperatures. In combination with studies using optical and electron microscopy and X-ray analysis, mechanical properties were tested for tensile strength at room temperature. It has been established that the aged alloy is distinguished by a high level of mechanical properties (tensile strength up to 1200 MPa with a relative elongation of up to 35 %) due to highly dispersed homogeneous decomposition and the effect of simultaneous hardening and increased plasticity as a result of deformation-induced martensitic transformation.
Relaxation of the Excess Free Volume of the Phase Transformation at the Interphase Boundary between the Crystal and the Melt
Authors: Esin V. O.
Published: September 2024

The mechanism of relaxation of the excess free volume of phase transformation released in the region of local dilation at the interphase boundary (MFG) of a crystal with a melt is considered. The analysis of the structural state of the MFG and its effect on the mobility of the boundary under the conditions of pressure application during the growth of the crystal from the melt is carried out. An explanation is given of the extreme influence of pressure on the mobility of the MFG and the possibility of the state of abnormally high mobility of the boundary under conditions of the application of “optimal” pressure in magnitude (“super-mobility” of the MFG). Within the framework of the mechanism of viscous melt flow into the region of local dilation at the MFG, which occurs during crystallization, a quantitative agreement was obtained with the experimental value of the “optimal” pressure in terms of magnitude, which determines the extreme nature of the mobility of the crystal boundary with the melt.
Morphology of dissipative structures formed during the high-temperature synthesis of the MgB2 compound
Authors: Esin V. O.
Published: September 2024

The interaction of components during high-temperature annealing of compressed magnesium and boron powders in the technologies for obtaining the superconducting compound MgB2 in works using standard synthesis technology and hot gas-static pressing technology is considered. The effect of the kinetics of crystal growth and diffusion of components released at the interface on the morphology of dissipative structures formed during phase transformation is studied in a computer model of crystallization of a binary alloy. The conditions and mechanism of formation of “dendrite-like” and “layered” structures arising during crystallization of MgB2 from magnesium melt (Mg –%B) are analyzed. It is shown that the application of pressure during the synthesis of the compound makes it possible to control the morphology of the resulting dissipative structures that determine the degree of development of porosity and liquation heterogeneity of the composition in a massive superconductor.
Order-disorder phase transitions in Fe81Ga19-RE ALLOYS (RE = Dy, Er, Tb, Yb) according to neutron diffraction data
Authors: Balagurov A. M. , Yerzhanov B. , Мухаметулы Б. , Samoylova N. Yu. , Palacheva V. V. , Sumnikov S. V. , Golovin I. S.
Published: September 2024

New data on the phase compositions and structural transformations in a number of Fe81Ga19 alloys doped with trace amount (≤ 0.2 at.%) of rare earth elements are presented. The data are obtained in neutron diffraction experiments performed with high resolution and in continuous temperature scanning mode when heated to 900 °C and subsequent cooling. It has been established that structural rearrangements proceed in a generally identical manner both in the original Fe81Ga19 alloy and in its doped analogues. Slow heating and subsequent cooling of the alloys (rate ±2 °C/min) leads to the formation of clusters of the D03 phase with sizes in the range (200–300) Å in the matrix of the disordered A2 phase. The sizes and volume fraction of clusters (~0.3 of the sample volume) weakly depend on the specific composition. The degree of ordering of the clusters atomic structure changes with temperature according to a second-order phase transition and is close to unity at room temperature. The search for structural ordering corresponding to the modified D03 phase, discovered in a number of electron diffraction studies, did not lead to a positive result.
Features of Phase Composition and Structure of Rapidly Quenched Ferromagnetic Mn–Al–Ga Alloy
Authors: Fortuna A. S. , Morozova T. A. , Karpenkov D. Yu. , Gorshenkov M. V.
Published: September 2024

Rapidly quenched Mn55Al36Ga9 ribbons were obtained by the spinning method. In the initial quenched state, the ribbons had a two-phase structure of the ε and γ2-phases. It has been established that, upon heating, the alloy undergoes a series of phase transformations, including the precipitation of the equilibrium β-Mn phase and its subsequent dissolution, the formation of the ferromagnetic τ-phase from both the ε and γ2-phases. The largest amount of the τ-phase was obtained by annealing at a temperature of 700 °C for 20 minutes. The work describes both the phase composition obtained as a result of annealing at different temperatures and the features of the microstructure studied by electron microscopy.
Influence of deformation and annealing on the structure, electrical resistance and hardness of the Al–4 %Cu–3 %Mn alloy casted in an electromagnetic crystallizer
Authors: Belov N. A. , Cherkasov S. O. , Korotkova N. O. , Motkov M. M.
Published: September 2024

Using computational and experimental methods, the influence of deformation-heat treatment on the structure, electrical resistance and hardness of the Al–4 %Cu–3 %Mn alloy produced by casting in an electromagnetic crystallizer was studied. It has been shown that at a cooling rate of more than 1000 K/s, the entire amount of manganese and half of the total copper content are dissolved in the aluminum solid solution, which allows, with subsequent deformation-thermal treatment, to form a structure with the maximum possible number of Al20Cu2Mn3 dispersoids, which allows achieving significant increasing heat resistance compared to known alloys of the Al–Cu–Mn system.
Initiation of the Shape Memory Effect by Fast Neutron Irradiation
Authors: Bobrovskii V. I. , Afanasyev S. V. , Voronin V. I. , Kazantsev V. A. , Kataeva N. V. , Parkhomenko V. D. , Proskurnina N. V. , Sagaradze V. V.
Published: September 2024

The band sample of austenitic steel 0.3C–13Cr–10Mn–3Si–1V was cold deformed to a shape of circular arc with a deflection of 3 mm and then irradiated by fast neutrons with a fluence of 6×1019 cm–2 in the vertical wet channel of the IVV-2M reactor at a temperature of 80 °C. This material belongs to the class of the stainless manganese austenitic steels with the shape memory effect (SME). The neutron irradiation was initially supposed to lower the SME upon the further heating in comparison with the reference sample. But instead, the SME appeared immediately under irradiation showing a decrease in the deflection of about 21 %. Check experiments confirmed that the lower limit of the SME in this material is 120 °C with its absence at 80 °C. This allows us to assert that the observed effect is the result of the neutron irradiation.
Investigation of the absorption properties of multilayer composites based on ABS-plastic with boron nitride
Authors: Kovalenko N. A. , Tarnavich V. V. , Chetverikov Y. O.
Published: September 2024

Modeling of absorption capabilities of different plastics, including those with different content of boron nitride for ABS-plastic was performed. Modeling was carried out using the PHITS software package. The paper compares the results of modeling the absorption capacity of plastic with experimental data. The case of practical application of ABS-plastic as neutron-absorbing shutters of a diaphragm is considered.
On the Multi-Layered Adsorption of Alcanols in the Vicinity of Liquid–Vapor Transition at the Saturated Hydrocarbon–Water Interface
Authors: Tikhonov A. M. , Volkov Yu. O.
Published: September 2024

Structure of adsorption layer of long-chain monoatomic alcohols: 1-dodecanol and 1-tetracosanol at the interfaces n-hexane – water and n-hexadecane – water in the vicinity of “liquid – vapor” thermotropic phase transition is investigated by the method of X-ray reflectometry at synchrotron source. Model-independent structural data obtained on the adsorption layers under investigation deviate considerably from the structural parameters which have been proposed previously within a model-based representation and discussed in previous publications on said systems. It is shown that in the low-temperature mesophase the adsorption film consists of a Gibbs monolayer, a transitional liquid region with thickness of two to three monolayers ~50 Å and an extended (wide up to 200 Å) layer of micelles. Presence of a plane of the closest approach of micellar layer to the adsorption film at the interface is established. Transition to the high-temperature mesophase is followed by liquefying and partial evaporation of alcanol film along with observed depletion of micellar layer down to its complete disappearance.
Investigation of Plasticity in Memristive Structures Based on Epitaxial Films Nd2–xCexCuO4–y
Authors: Tulina N. A. , Rossolenko A. N. , Shmytko I. M. , Borisenko I. Yu. , Ivanov A. A.
Published: September 2024

Pulse studies of resistive switching in memristive planar heterocontacts based on Nd2–xCexCuO4–y epitaxial films are presented. The possibility of regulating the resistive metastable states of memristive planar systems based on such films according to certain pulse research protocols has been studied. Various metastable states were realized when changing external parameters: frequency, voltage of the electric field applied to heterocontacts. Dynamic effects have been investigated, and transition times from one metastable state to another have been determined. The change in electrodynamic properties during the action of a sinusoidal alternating electric field at frequencies of 10–3 Hz and in pulse mode with a pulse duration from 0.1 ms to 25 s was directly investigated by measuring the volt-ampere characteristics, recording oscillograms of current and voltage at the heterocontact and temperature dependences of resistance of metastable phases. The multilevel nature of the metastable resistive states of the studied systems and the ability to adjust the switching time characterize the plasticity of these devices and the prospects for their use as memory elements for neuromorphic applications in spike neural networks.
Mechanoluminescence and Optically Stimulated Antistokes Luminescence of Composites Based on Epoxy Resin and Strontium Aluminate Phosphors SrAl2O4:Eu2+,Dy3+ and Sr4Al14O25:Eu2+, Dy3+
Authors: Banishev А. F.
Published: September 2024

Composite mechanoluminescent materials (composites) based on epoxy resin transparent in the visible range of spectrum and fine-dispersed powders of mechanoluminescent phosphors SrAl2O4:Eu2+, Dy3+ and Sr4Al14O25:Eu2+, Dy3+ were obtained. The mechanoluminescence and photoluminescence spectra of composites under the combined influence of short-wave (λ = 405 nm) and long-wave (λ = 1.06 µm) laser radiation were studied. The attenuation of optically stimulated antistokes luminescence of the composite under the influence of a sequence of pulses of longwave laser radiation was investigated. The composite was pre-irradiated with shortwave laser radiation. The obtained composite was used to visualize heat propagation and thermal deformations in metal plates arising under the action of powerful laser pulses and distribution of deformations under mechanical impact. For this purpose, a thin layer of the composite was applied to the surface of the materials under study. The composite had good adhesion to the surface of the materials and a high yield of mechanoluminescence, which allowed to visualize the distribution of temperature and surface deformations with a good spatial and temporal resolution.
Study of the Influence of Ferromagnetic Impurity Concentration on Magnetic Properties of Binary Palladium–Cobalt Alloy
Authors: Gumarova I. I. , Gumarov A. I. , Yanilkin I. V.
Published: September 2024

A comparative study of the magnetic properties of a palladium–cobalt alloy with an impurity content of up to 0.05 at. % was made using calculations based on the density functional theory and experimental methods. It was found that the alloys had ferromagnetic ordering, which depended on the impurity concentration. At very low concentrations, less than 1 at. %, the magnetic moment per impurity atom can reach 25 µB.
Determination of the Activation Energy of Defects in Ferroelectrics by the Method of Temperature Activation–Relaxation of the Dielectric Permittivity
Authors: Kuzenko D. V.
Published: September 2024

The article proposes a method of temperature activation–relaxation of the permittivity for determining the activation energy of defects in ferroelectrics using lead zirconate–titanate Pb(Zr,Ti)O3 samples as an example. This method is based on the analysis of relaxation of the permittivity after thermal annealing and the analysis of the temperature activation of the permittivity of the Pb(Zr,Ti)O3 ferroelectric. The equality of the activation energy corresponding to the process of migration of oxygen vacancies and the thermal energy of the decay of the domain structure was established, which was confirmed by studying the surface of the samples by scanning electron microscopy. When this temperature was reached, the surface of the domain walls was detached from oxygen vacancies, which are pinning centers. This manifested itself in photographs of the microstructure as a change in the ordering of the domains emerging on the surface of the sample, which led to an irreversible decrease in the permittivity of the sample. For the obtained activation energies, the physical process of domain wall motion activation is established, which is determined by their pinning on structural defects (oxygen vacancies). It is assumed that the irreversible decay of the domain structure occurs when the domain walls are displaced by distances exceeding the elementary lattice parameter of the ferroelectric. The proposed method can be part of a comprehensive study that includes electrophysical, microscopic and X-ray methods.
Study of Hydrogen Migration in Titanium Using a Vortex Electromagnetic Field and Accelerated Electrons in Subthreshold Values
Authors: Tyurin Yu. I. , Larionov V. V.
Published: September 2024

The migration of hydrogen in an in homogeneously hydrogen-saturated commercial titanium VT1-0 has been studied using a high-frequency electromagnetic field and an accelerated electron beam. The use of a high-frequency 50–1000 kHz electromagnetic field, which generates eddy currents in the material, made it possible to observe the process of hydrogen migration near the surface and in the depth of the sample. To accelerate the migration of hydrogen in the volume of the sample, electron irradiation with an energy of 30–45 keV was used. The migration process was studied in an inhomogeneously hydrogen-saturated commercial titanium sample with a titanium nitride film deposited on its surface by magnetron sputtering. Flat samples VT1-0 were saturated with hydrogen using the Sieverts method. The diffusion coefficient of hydrogen in titanium was determined from the change in the magnitude of the signal from the eddy current sensor along the depth of the sample and along the sample, as hydrogen migrated in the sample. The values of the diffusion coefficients of hydrogen along the surface and in the depth of the sample under equilibrium conditions and under stimulation by an accelerated electron beam are obtained.
Deposition of Wear-Resistant Nanocomposite Coatings from Accelerated С60 Ions
Authors: Pukha V. E. , Drozdova E. I. , Chernogorova O. P. , Lukina I. N. , Petrzhik M. I. , Belmesov A. A.
Published: September 2024

Hard wear-resistant carbon coatings were deposited from accelerated C60 ions at temperatures of 200 and 300°C. It has been established that the mechanical properties of the coatings are determined by the substrate temperature (Ts) and the energy composition of the beam. The hardness of coatings deposited from C+60 ions with an energy of 7 keV exceeds 50 GPa and is virtually independent of Ts. The presence of C602+ and C603+ with an energy of ~14 and 21 keV, respectively, in the beam leads to a result that is not typical for carbon coatings – the hardness increases by more than 1.3 times with an increase in Ts from 200 to 300°C (from 31.6 GPa to 41.6 GPa). In this case, according to Raman spectroscopy data, the size of graphite nanocrystals in the coating increases with temperature up to almost 2 nm. Coatings obtained under conditions of irradiation with C602+ and C603+ ions are characterized by minimal wear (1.5×10–8 mm3/N∙m, Ts = 200°C) and minimal friction coefficient (µ = 0.05 for Ts = 300°C). We attribute the unusual dependence of hardness on Ts and the improvement in the tribological properties of coatings to the formation of a composite structure based on a diamond-like matrix and graphite nanocrystals in this range of Ts.