bluuebunny/crossref_metadata_2025 huggingface dataset:
Larvicidal and Ovicidal Properties of Essential Oils Derived from Origanum minutiflorum and Salvia dorystoechas against the Aedes aegypti
Authors: Gültekin Zeynep Nur , Kahraman Şevval , Çetin Hüseyin
Published: April 2024

This study assessed the larvicidal and ovicidal effects of essential oils extracted from the above ground of Origanum minutiflorum and Salvia dorystoechas, belonging to the Lamiaceae plant family, on Aedes aegypti mosquito larvae and eggs. The research utilized essential oil concentrations ranging from 1 to 100 ppm. Larvicidal activity was evaluated 6 hours post-exposure and subsequently at 24-hour intervals over a period of 5 days while ovicidal activity was monitored every 2 days for a total of 10 days. Findings indicated that both essential oils demonstrated significant larvicidal effects at 50 and 100 ppm concentrations against Ae. aegypti larvae. In contrast, ovicidal effects were not observed to be statistically significant. Throughout the experiment, O. minutiflorum essential oil consistently showed higher larvicidal potency compared to S. dorystoechas. Therefore, while essential oils from both O. minutiflorum and S. dorystoechas effectively target Ae. aegypti larvae, especially at elevated concentrations, they did not exhibit ovicidal properties.
DEVELOPMENT OF A DIGITAL PROFILE TO ENSURE DIGITAL LEADERSHIP OF THE ENTERPRISE
Authors:   Public Higher Educational Establishment «Vinnytsia Academy Of Continuing Education», Vinnytsya, Mazur H. F.
Published: April 2024

The article clarifies the content and components of the digital profile of the enterprise, the essence of digital leadership is clarified, the digital tools used by digital leaders in Ukraine are considered, the characteristic features of digital leaders are identified (the presence of a clear vision and strategy for the use of digital technologies; the presence of a flexible digital profile; constant encouragement digital innovations; transparency and communication; high organizational and digital culture; constant changes in competencies; risk-orientation in order to open new opportunities). Key decisions regarding becoming a digital leader are covered, including: development of a clear digital strategy that defines the purpose, goals, tasks and methods of implementing modern digital technologies; stimulation of innovation and implementation of new digital initiatives; attraction of qualified personnel; implementation of data analytics; close communications and relationships with clients; flexible digital profile; ensuring security and data protection; continuously improving its digital initiatives and implementing new technologies to remain a leader in the digital space. The provisions of digital strategies are motivated, the consideration of which will help the enterprise to take steps towards the digital leader and ensure its competitiveness in the digital world. The advantages of digital leadership of the enterprise are defined, in particular, it is stated that digital leaders have the following advantages in the market: they use advanced technologies and innovative solutions, which allows them to get ahead of their competitors, they easily scale their business, quickly expand to new markets and attract new customers; the use of digital tools allows them to use their resources efficiently and increase productivity; they have access to large volumes of data and analytical tools, which they use to improve their strategies and make informed decisions; they use digital media and platforms to improve communication with their customers and provide them with a personalized service, and their strategies are unique and multi-layered, which gives them additional competitive advantages. All these advantages make digital leaders stronger competitors in the market, and help them attract and retain customers, improve productivity, maximize profits and effectiveness.
DEVELOPMENT OF ENTERPRISE STRATEGY IN CURRENT ECONOMIC CONDITIONS
Authors:   State University of Information and Communication Technologies, Kyiv, Makovetska I. M.
Published: April 2024

The article is devoted to the development of the company's strategy in modern economic conditions, which would allow to improve the activity and direct the forces to new horizons of doing business with strengthened positions both in the internal and external environment of the company. The difficult situation in the domestic market and European integration require domestic enterprises to search for new effective ones tools for further development and increasing the competitiveness of goods. One of these tools is determining the position of the enterprise and the product or service, as well as effective strategy development. The process of developing an enterprise strategy is described, where everything begins with defining the global mission of the enterprise and goals that are more specific and global for the management process itself. According to this model, the process of strategic management is a certain point of intersection of identified opportunities and threats of the enterprise's external business environment, which are expressed in the form of key success factors, as well as strengths and weaknesses of resource potential, expressed in excellent development capabilities. The vast majority of one or another component in the company's final strategy depends on the level of instability of the company's operating environment. The more changeable and unstable the external environment, the more random creative and creative approach of managers to the assessment of a given situation in the company's strategy. A detailed classification of types of enterprise strategy is given, which includes the content, management decision-making, behavior in the internal and external environment, the level of strategy implementation, and industry directions of the enterprise before developing one or another strategy in modern economic conditions. Four different approaches to the growth of an enterprise with the development of a strategy are analyzed, which are associated with a change in the state of one or more of the following elements: product, market, industry, position within the industry, technology. The development of an enterprise's strategy in modern economic conditions should ensure the orientation and adaptability of the enterprise's actions.
FINANCIAL MANAGEMENT STRATEGIES TO ENSURE STABILITY OF INSURANCE COMPANIES AMID CRISIS SITUATIONS
Authors:   Taras Shevchenko National University of Kyiv, Kyiv, Rasshyvalov D. P.
Published: April 2024

In the face of economic crises and emergencies, insurance companies are tasked with maintaining stability to safeguard their operations and the interests of policyholders. This article explores various financial management strategies employed by insurancecompanies to ensure stability during crisis situations. The relevance of this topic is underscored by the crucial role insuranceplays in mitigating financial risks for individuals, businesses, and society at large. The aim of this research is to analyze the effectiveness of different financial strategies used by insurancecompanies to overcome crisis situations. Such strategies encompass a range of measures, including robust risk management systems, balanced investment policies, adequate capital reserves, and active asset and liability management methods. By examining these strategies, this study aims to offer insights into how insurancecompanies can enhance their resilience and adaptability amid turbulent economic conditions. Through empirical analysis and case studies, this research elucidates the advantages and drawbacks of implementing various financial management strategies during crisis situations. It identifies key success factors and challenges faced by insurancecompaniesstriving to maintain stability amidst uncertainty. Additionally, the study evaluates the impact of these strategies on financial performance, solvency, and overallresilience of insurancecompanies. The conclusions drawn from this research underscore the importance of proactive financial management in ensuring the stability of insurancecompanies during crises. It also emphasizes the significance of adopting a comprehensive and predictive approach that integrates risk identification, mitigation, and contingency planning into insurers’ core operations. On the other hand, the research findings highlight the crucial role of regulatory oversight and industry collaboration in fostering a stable and resilientinsurance sector. Conducting further scientific research on financial management strategies to ensure stability of insurancecompanies during crisis situations holds significant potential for enhancing resilience in this sector. Assessing the effectiveness of various risk management methods, such as hedging and diversification, will provide better insights into reducing financial instability. Investigating the role of regulatory framework and its impact on the stability of insurancecompanies during crises can offer important recommendations for policymakers and industry practitionersalike.
Diagnósticos retrasados y administración de ondansetron en el tratamiento de los vómitos en urgencias pediátricas
Authors: Cabral Isaura , Pavlicich Viviana , Godoy Sánchez Laura E , Mesquita Ramirez Mirta N
Published: April 2024

Introducción: El ondasentrón es un agente farmacológico de uso frecuente para el tratamiento sintomático de los vómitos originados por gastroenteritis. Sin embargo, podría enmascarar patologías más graves que ameriten reconsultas y hospitalización.
Objetivo: Indagar si la administración del ondansetrón como tratamiento sintomático de los vómitos en el departamento de emergencias pediátricas (DEP) retrasó el diagnóstico de patologías graves.
Materiales y métodos: Estudio observacional, descriptivo de corte transverso retrospectivo. Fueron elegibles pacientes que consultaron en el DEP, recibieron tratamiento con ondansetron, y reconsultaron dentro de las 24 horas.  Los datos fueron recolectados de la base de datos de consultas del DEP, el comando reconsultas y entrevista telefónica a los padres. Las variables fueron edad, sexo, procedencia, motivo de la segunda consulta, diagnósticos finales en la segunda consulta. Los datos fueron analizados en SPSS utilizando estadística descriptiva.
Resultados En el periodo de estudio consultaron por vómitos y recibieron ondasentrón 2018 pacientes. Reconsultaron dentro de las 24 horas 212, cumpliendo con los criterios de inclusión 205 pacientes. Se constató un 24,8% nuevos diagnósticos durante la reconsulta, de los cuales 35% requirieron hospitalización. Los diagnósticos fueron fiebre sin foco 2,9%, neumonía 2,4%, infección de vías urinarias 1%, sospecha de chikunguya 1,5%, adenitis mesentérica 0,5%, abdomen agudo quirúrgico 0,5%.
Conclusión: Se identificó diagnósticos diferentes a la primera consulta en pacientes que recibieron ondansetrón como tratamiento sintomático de los vómitos en urgencias pediátricas, requiriendo hospitalización el 35% de los mismos.
СУБ’ЄКТНІСТЬ ЯК ФАКТОР ВІДНОВЛЕННЯ ДЕОКУПОВАНИХ ТЕРИТОРІЙ
Authors: Соколенко К. В.
Published: April 2024

Містобудівний аналіз, містобудівне проєктування спирається на показники, головним з яких є чисельність населення. Розроблено класифікацію категорій деокупованих територій залежно від терміну та наслідків перебування їх під окупацією. Досліджено вплив груп та категорій населення деокупованих міст, перспективи їх відновлення.Запропоновано класифікацію суб’єктності окремих категорій населення залежно від притаманних видів діяльності. Розроблено модель формування суб’єктів містобудівного розвитку.
FEATURES OF PHYSICAL TRAINING OF POLICE OFFICERS UNDER MARTIAL LAW: CHALLENGES AND TASKS
Authors: PETRUSHYN Dmytro , LAHUN Karyna
Published: April 2024

The article addresses the pressing issue of police physical training during times of martial law. In the midst of conflicts and threats to national security, police officers are tasked with crucial responsibilities in maintaining public order and ensuring citizen safety. However, martial law presents them with a series of complex challenges and tasks, heightened threats, and demands increased readiness. The article explores the specifics of police physical training in martial law conditions and analyzes key aspects of this process, including physical fitness requirements, training methods, and effectiveness assessment. The authors emphasize the importance of a systematic approach to police physical training, taking into account the specific needs and circumstances of martial law. Additionally, the research sheds light on potential strategies and recommendations for police officers in preparing for actions in wartime conditions, enhancing their effectiveness, and ensuring citizen safety. The findings of this article may be valuable for police organizations and policymakers involved in developing strategies and policies related to the training of law enforcement personnel during martial law.
FEATURES OF INFLUENCE OF JEALOUSY ON CONFLICTS IN THE FAMILY
Authors: SHINKARENKO Іnna
Published: April 2024

The article provides a theoretical study and a new perspective on the phenomenon of jealousy in love relationships and its impact on the occurrence of conflict situations between a couple regarding the understanding of relationships, jealousy and love. Investigated manifestations of jealousy in a deformed form have been studied. It is emphasized that experiencing personal jealousy is a strong affective feeling that globally disorganizes human relations, causes stressful situations, and generates both interpersonal and intrapersonal conflicts. It was determined that destructive manifestations of jealousy are an extremely negative phenomenon, because they are built on different complexes and represent a mental disorder that must be treated. The relevance of the existing problems and the uncertainty regarding the classification of jealousy and the subsequent correlation of its indicators with certain models of personality behavior in conflict situations became the reason for the appearance of this article.
THE USE OF MODERN TECHNOLOGIES IN THE TACTICAL AND SPECIALISED TRAINING OF POLICE OFFICERS UNDER MARTIAL LAW
Authors: BOIKO Olena , MELNYK Andrii
Published: April 2024

The article analyses the possibilities of using modern technologies in the tactical and specialised training of police officers under martial law. Martial law creates emergency situations when police officers have to work in conditions of increased danger and instability. In such circumstances, the use of modern technologies in tactical and specialised training of police officers becomes extremely important in order to ensure their safety, efficiency and success in performing their tasks. The article outlines the benefits of using technologies such as virtual reality, augmented reality, unmanned aerial vehicles, robotic systems and artificial intelligence. Thus, the main areas of application of modern technologies in the tactical and special training of police officers are: the use of virtual reality and augmented reality to develop practical skills, in particular for training in combat operations, which ensures more effective training of police officers; the use of unmanned aerial vehicles to monitor and obtain information about the situation on the ground without risking the lives of police officers; the use of robotic systems to perform dangerous or difficult tasks, in particular tasks of search and rescue; the use of virtual reality and augmented reality to develop practical skills, in particular for training in combat operations, which ensures more effective training of police officers; the use of virtual reality and augmented reality to develop practical skills, in particular for training in combat operations, which ensures more effective training of police officers. It is noted that the use of modern technologies can increase the effectiveness of police training, reduce the risk to their lives and improve the safety of citizens. The author concludes that the use of modern technologies is an integral part of the tactical and specialised training of police officers under martial law. Technology helps police officers to effectively counter threats, provide security and be successful in their work. The development and improvement of these technologies is an important area for improving the effectiveness of police work under martial law. The introduction of modern technologies in tactical and specialised training of police officers is an important task that will increase the effectiveness of police activities under martial law.
Examining honey production with Geographic Information Systems (GIS): The example of Ordu province
Authors: Arslan Emre , Bayir Tuba , Inal Seref
Published: April 2024

Beekeeping is an example of economic farming with its products that can be done without being dependent on plant and ecological production because of its contribution to pollination. This study aims to examine Ordu province, which has been at the top of Turkey's beekeeping activities and honey production for years, with Geographic Information Systems (GIS) based on honey production data between 2013 and 2022. By evaluating the honey production data of registered breeders in Ordu province, cartographic maps were produced to evaluate the spatial projection of honey production for the last ten years. After creating a GIS-based database, district-based shape file (.shp extension) data was used for spatial analysis and mapping of the obtained outputs. After these data were defined in the WGS 84 EPSG:4326 coordinate reference system, the spatial distribution of honey production and yield throughout the study period was analyzed using the open-source QGIS version 3.18.3 software. It was determined that the highest honey production belonged to registered beekeepers in Altınordu district during the relevant time period. Altınordu is also the district with the highest number of registered enterprises. It was determined that the honey production data and the number of enterprises of the beekeepers in Gülyalı district, which is one of the neighbouring districts of this district, are lower than Altınordu district. After Altınordu district, Perşembe, Ulubey, Gürgentepe and Gölköy districts have an important place in honey production. Although these districts are neighbours like Gülyalı district, their high production may have resulted from the difference in cooperation between the districts. As a result, it was determined that honey production activities in Ordu province and districts, which is an important city in terms of honey production, vary depending on the districts. The problem of climate change, which is predicted that the world will be exposed to more in the near future, also directs beekeeping activities towards nomadic beekeeping. It can be said that like most of the breeders in Ordu province, registered beekeepers in other cities will be more orientated towards nomadic beekeeping against the threat of global warming.
Sistem Pembayaran Tunai Dan Non Tunai Pada PT. Kedamaian
Authors: Alfiana Yeni , Veronica Aries , Yanti Dwi , Winarsih Wiwin
Published: April 2024

ABSTRAK
 
The purpose of this research is to determine the differences in payment systems implemented by PT. Peace before and after cash and non-cash payments are made to the profit and loss statement by analyzing financial ratios and seeing the differences. The analysis technique used is the Paired Simple T-Test. The results of this research show that the sig cash ratio value is 0.347 > 0.05, there is no difference in the cash ratio between the income statement before and after the non-cash payment system. The sig value of Debt to Total Asset Ratio is 0.245 > 0.05, there is no difference in Debt to Total Asset Ratio between the income statement before and after the non-cash payment system. The sig value of Debt to Equity Ratio is 0.188 > 0.05, there is no difference in the Debt to Equity Ratio between the income statement before and after the non-cash payment system. The Profit Margin sig value is 0.915 > 0.05, there is no difference in Profit Margin in the income statement before and after the non-cash payment system. This shows that there is no significant difference before and after the non-cash payment system on the profit and loss statement, although only part of several variables.
 
Keywords: Profit and loss report, cash and non-cash payment systems, financial ratios.
 
ABSTRAK
 
Tujuan dari penelitian ini adalah untuk mengetahui perbedaan sistem pembayaran yang diterapkan oleh PT. Kedamaian sebelum dan sesudah dilakukan secara tunai dan non tunai terhadap laporan laba rugi dengan cara menganalisis rasio keuangan dan dilihat perbedaannya. Teknik analisis yang dipakai ialah Uji Paired simple T-Test. Hasil penelitian ini menunjukan nilai sig cash ratio bernilai 0.347 > 0.05,  tidak ada perbedaan cash ratio antara laporan laba rugi sebelum dan sesudah sistem pembayaran non-tunai. Nilai sig Debt to Total Asset Ratio bernilai 0.245 > 0.05,  tidak ada perbedaan Debt to Total Asset Ratio antara laporan laba rugi sebelum dan sesudah sistem pembayaran non-tunai. nilai sig Debt to Equity Ratio bernilai 0.188 > 0.05, tidak ada perbedaan Debt to Equity Ratio antara laporan laba rugi sebelum dan sesudah sistem pembayaran non-tunai. Nilai sig Profit Margin bernilai 0.915 > 0.05, tidak adanya perbedaan Profit Margin pada laporan laba rugi sebelum dan sesudah sistem pembayaran non-tunai. Ini menunjukan bahwa perbedaan sebelum dan sesudah sistem pembayaran non-tunai terhadap laporan laba rugi, tidak ada perbedaan signifikan, walaupun hanya sebagian dari beberapa variabel.
 
Kata Kunci : Laporan laba rugi, sistem pembayaran tunai dan non-tunai,rasio keuangan.
The Role of Supervision of the Board of Commissioners in the Company PT. XYZ
Authors: Chandra William , Wijayati Nureni
Published: April 2024

The importance of implementing good governance principles that do not just focus on formality, but on substance for public companies is important. This research aims to of paying more attention to corporate governance in the context of the ASEAN Corporate Governance Scorecard. The method used in this research uses a qualitative approach. the research results found that a focus on board diversification, meeting minutes, appointment of a corporate secretary, and evaluation of board performance can provide a strong foundation for increasing transparency, accountability, and corporate resilience amidst ever-evolving business dynamics. Emphasis on the inclusion of independent commissioners, the formation of special board committees, and the introduction of best governance practices are also important in facing regulatory changes and industry dynamics.
Modifying Copper with Alumina
during a Mechanically Stimulated Reaction
Authors: Grigoreva T. F. , Talako T. L. , Devyatkina E. T. , Vosmerikov S. V. , Ancharov A. I. , Tsybulya S. V. , Vityaz P. A. , Lyakhov N. Z.
Published: April 2024

IR spectroscopy, electron microscopy, and X-ray diffraction analysis, including the application of synchrotron radiation, have been used to study the mechanochemical reduction of copper oxide with alumi-num at the stoichiometric ratio of the components and in the presence of an excess of oxide-forming metal and aluminum solid solution in copper as well. The possibility is shown of the mechanochemical reduction of copper oxide with aluminum and aluminum solid solution in copper, which is accompanied by the forma-tion of the Сu/Al2O3 composite structure. To modify copper with alumina, using an aluminum solid solution in copper is preferable.
The Microstructure and Magnetic Properties
of the Strip-Cast (Sm,Zr)(Fe,Co)10.3Ti0.7 Alloy
Authors: Protasov A. V. , Popov A. G. , Volegov A. S. , Gaviko V. S. , Shitov A. V. , Golovnya O. A.
Published: April 2024

Sm(Fe,Co,Ti)12-based alloys with low contents of rare-earth elements are promising materials for manufactoring high-energy permanent magnets. The (Sm,Zr)(Fe,Co)10.3Ti0.7 alloy has been produced by strip casting with low quenching rates. The structure and magnetic properties of the alloy were studied by scanning electron microscopy, as well as X-ray and thermomagnetic analysis. The initial inhomogeneous alloy was subjected to solid-solution treatment at 1150°С. The alloy retained a high-anisotropy state typical of the Sm(Fe,Co,Ti)12 phase.
Analysis of Compositional Nuclear Transmutation Effects
in Vanadium Alloys under Irradiation
Authors: Belozerova A. R. , Belozerov S. V.
Published: April 2024

The effects of nuclear transmutation in vanadium-based alloys under irradiation are considered in different reactor units including fast breeder reactors, such as (1) BOR-60 (experimental fast reactor), (2) EBR-II (experimental breeder reactor), and ITER (international thermonuclear experimental reactor). A comparison of nuclear transmutation rates for the analyzed [V–x% Cr(Ni)–y% Ti] alloys by data mining facilities is performed. It is demonstrated that the dominant types of interactions between neutrons and tested materials correlate with the level of thermalization in the neutron spectrum of a reactor, which has an effect on the value of nuclear transmutation rates to lead to distinctions in the resulting chemical composition of alloys after irradiation.
Temperature-Rate Conditions of Deformation
and Structure-Forming Processes in Nickel
during High-Pressure Torsion
Authors: Karamyshev K. Yu. , Chashchukhina T. I. , Voronova L. M. , Degtyarev M. V. , Pilyugin V. P.
Published: April 2024

Scanning and transmission electron microscopy has been used to investigate the nickel structure formed by high pressure torsion deformation at temperatures of 100–250°C. The relationship between the structure and temperature–rate conditions of deformation, which is characterized by the Zener–Hollomon parameter (Z), has been found. A change in the temperature–rate conditions of deformation has been shown to alter the dominant structure-forming process and to change the resultant structure. We have identified lnZ ranges where these processes occurred, namely, dynamic recovery at lnZ 25, dynamic recrystallization at 21 lnZ 25, and dynamic polygonization at lnZ 21.
The Influence of Exchange Correlation Effects on the Stabilization
of the Half-Metallic Properties of Mn2VAl and Mn2VSi Alloys
Authors: Buchelnikov V. D. , Baigutlin D. R. , Sokolovskiy V. V. , Miroshkina O. N.
Published: April 2024

Theoretical studies of the role of exchange correlation effects in the prediction of the half-metallic properties of ferrimagnetic Mn2VAl and Mn2VSi Heusler alloys, which are of interest in spintronics, are pre-sented. Electronic, magnetic, and structural properties are studied within the framework of density functional theory. It is shown that the correction for additional correlation effects makes it possible to reveal two states, which are close to each other in energy, but have different magnetic moments. The state with a low magneti-zation demonstrates a half-metallic character with 100% spin polarization, whereas the state with a high mag-netization has a metallic character.
The Dynamic Proximity Effect in Superconductor –Ferromagnetic Insulator Hybrid Structures
Authors: Turkin Ya. V. , Pugach N. G. , Ekomasov E. G. , L’vov B. G.
Published: April 2024

This paper presents a theoretical study of the dynamics of the induced magnetization and spin cur-rent arising in a layer of an impure superconductor due to the proximity to a ferromagnetic dielectric with a uniform periodically precessing magnetization. The dynamics of the observed physical quantities is described within the semi-classical Usadel–Floquet formalism, which makes it possible to study the effect of a periodic perturbation on an inhomogeneous superconducting system. The spatial distributions and temporal evolu-tion of the induced magnetization and the superconducting spin current inside the superconductor layer are found from the numerical solutions of the system of Usadel–Floquet equations.
On the Origin of Magnetoelectric Phenomena in Iron Garnet Films
Authors: Kaminskiy A. S. , Myasnikov N. V. , Pyatakov A. P.
Published: April 2024

The theoretical microscopic consideration of antisymmetric exchange in iron garnet crystals sub-jected to inhomogeneous deformation shows that the resulting inhomogeneous magnetoelectric effect causes electrically induced phenomena that are experimentally observed in domain walls of iron garnet films. In addi-tion, the gradient of epitaxial strains is sufficient for development of chiral magnetic structures in these films.
Superparamagnetism of Fe3O4–Fe3 – xTixO4 Composites:
Micromagnetic Modeling
Authors: Kharitonskii P. V. , Gareev K. G. , Ralin A. Yu. , Sergienko E. S.
Published: April 2024

The magnetic properties of Fe3O4–Fe3 – xTixO4 composites synthesized by various methods were simulated based on the model of an ensemble of magnetostatically interacting particles. The results are in good agreement with the hysteresis characteristics of the samples calculated earlier in the framework of the model of chemically heterogeneous two-phase particles. It is shown that the used approach is also applicable to the samples consisting mainly of superparamagnetic particles in which the saturation remanent magneti-zation is provided by the particles blocked due to the magnetostatic interaction.
The Effect of Milling with Combined Surfactants
on the Magnetic Properties and Microstructure
of Submicron Sm2Fe17N3 Powders
Authors: Kolodkin D. A. , Popov A. G. , Gorbunova T. I.
Published: April 2024

The results of the application of a combination of several surfactants in preparing submicron hard magnetic Sm2Fe17N3 powders by milling in a centrifugal mill are reported. Along with methyl caproate, to protect the powder against oxidation, the efficiency of siloxane has been studied. The application of the combined surfactants allowed us to increase both the (BH)max of the Sm2Fe17N3 powder to 23.6 MG Oe and its corrosion resistance. The effect of milling kinetics on the angular dependence of the coercive force Hc has been determined. Information on the primary mechanism of magnetization reversal of the powders has beenobtained.
Formation of Deformation Bands during Impact Indentation
of an Al–6Mg Alloy
Authors: Shibkov A. A. , Zolotov A. E. , Denisov A. A. , Gasanov M. F.
Published: April 2024

The nucleation and growth of macrolocalized deformation bands initiated by impact indentation in deformed aluminum-magnesium alloy samples have been investigated by acoustic emission and highspeed video recording with a time resolution to 50 μs. The indenter impact has been found to trigger the developmentof a ~1–3% amplitude plastic deformation macroscopic jump due to the nucleation and propagation of about ten deformation bands on an alloy surface, thus demonstrating the Portevin–Le Chatelier effect. Macrolocalized deformation bands are shown to be a dangerous type of erosion damage that can cause thesudden fracture of an alloy.
Application of Surfactant Activated Milling for Production
of Nd–Fe–B Magnets by PLP Technology
Authors: Golovnya O. A. , Kruchinina K. A. , Protasov A. V. , Kolodkin D. A. , Shitov A. V. , Stashkova L. A. , Ogurtsov A. V. , Taranov D. V.
Published: April 2024

The granulometric composition of Nd–Fe–B powders has been studied in detail after vibratory milling for various times both without and with the addition of siloxane. Sintered magnets were produced by the powder metallurgy method that excluded the pressing of powders. Correlations between the particle size distribution in the initial powders, microstructure of sintered magnets, and their magnetic hysteresis properties have been established. The difference in methods for estimating the size of powder particles by two methods is demonstrated. It is shown that the size distributions of powder particles and magnet grains are bimodal and are described by a superposition of two lognormal distributions.
The Effect of Magnetization Reversal Frequency
on the Dynamic Magnetic Hysteresis of a Plate
Made of Electrical Stee
Authors: Mironyuk N. E. , Samatov M. V.
Published: April 2024

Electrodynamic, quasi-static magnetic hysteresis loops and the form of the domain texture of a single-crystal plate have been experimentally obtained. Using mathematical modeling, the change in the dynamic magnetic hysteresis (the magnetic loss energy per unit volume per magnetization reversal cycle) depending on the frequency of the magnetic field is shown. This dependence is due to the inertia of the magnetization of the sample. With a change in frequency, the dynamic magnetic hysteresis can differ significantly from the hysteresis in the case of quasi-static magnetization reversal.
Diffusion Characteristics of Clusters of Self-Interstitial Atoms
in Vanadium: Molecular Dynamics Data
Authors: Demidov D. N. , Sivak A. B. , Sivak P. A.
Published: April 2024

The temperature dependences of diffusion characteristics of the irradiation-induced defects, namely, clusters of self-interstitial atoms (SIAs) containing up to five atoms, in bcc V (vanadium) have been studied by the method of molecular dynamics in the temperature range of 300–1000 K. The diffusion characteristics include the coefficient of diffusion, the tracer correlation factor, the average displacement before changing the direction of migration, and the frequency of changing the direction of migration. The values of the activation energy of diffusion and the activation energy of changing the direction of migration for the considered types of defects in different temperature ranges have been determined. The dependences of the mechanism of (1D vs 3D) diffusion of SIA clusters on the temperature and cluster size and their possible influence on the parameters of phenomenological models of changes in the microstructure of a material under irradiation (sink strengths of spherical absorbers) are discussed.
On the nucleation of cracks near stress sources with weak singularities
Authors: Kirikov S. V. , Perevezentsev V. N. , Pupynin A. S.
Published: April 2024

Analytical expressions are obtained for the configuration force and the value of elastic energy relaxation at the nucleation of a microcrack in a small neighborhood of an arbitrary singular stress source. When analyzing the conditions of crack nucleation at sources with weak divergences of the stress fields, ideas about the instantaneous nucleation of a crack of finite length are used. Simultaneous fulfillment of stress and energy conditions is considered as a criterion for the nucleation of such a crack. Within the framework of these representations, in the configuration space of the system parameters (geometric characteristics and strength of mesodefects, the value of external stress), the regions in which crack nucleation is possible in the case of a combined mesodefect, which is a superposition of the dipole of wedge disclinations and planar shear mesodefect, are determined. It is shown that the nucleation of the crack is significantly facilitated by the instability of the shear mesodefect.
Microsegregation of Alloying Elements on deformation Structural defects in Granular Nickel Alloy
Authors: Svetlov I. L. , Zaitsev D. V. , Karashaev M. M. , Epishin A. I. , Petrushin N. V.
Published: April 2024

Samples cut from a disk blank of Russian granulated nickel-based superalloy VZH178P were tested for tensile strength at room temperature and long-term creep at temperature of 750 °C. Transmission electron microscopy showed that, in both cases, stacking faults and microtwins formed during plastic deformation of the alloy. During long-term creep at 750 °C, the alloying elements Cr, Co, Mo, and W segregate on the stacking faults, leading first to the formation of Suzuki atmospheres and then to the nucleation and growth of TCP particles with stoichiometry (Co,Cr)3(Mo,W).
The Effect of Termomechanical Treatment
on the Low-Cyclic Fatigue Behavior in an Al–Cu–Mg–Ag Alloy
Authors: Gazizov M. R. , Gazizova M. Yu. , Zuiko I. S. , Kaibyshev R. O.
Published: April 2024

The mechanical behavior under monotonic and cyclic loadings has been studied in an Al–4.5Cu–0.56Mg–0.77Ag–0.42Mn–0.12Ti–0.05V–0.02Fe (wt %) alloy subjected to thermomechanical treatment (TMT), including a solution heat treatment, quenching in water, uniaxial tension with a plastic strain of 3%, andpeak aging at 190°C (state T83 according to the classification of the Aluminum Association). The T83-ed alloy demonstrates the lowest tensile strength properties in comparison with T6 state (traditional aging) and TMT,including rolling with a 40%-reduction (T840). Compared to T6 and T840 states, the lowest cyclic strength and cyclic strain hardening coefficients in the Ramberg-Osgood relationship was found to be in T83-ed alloy. To achieve long fatigue life, it is advisable to reduce to the minimum values the degree of intermediate plastic deformation required for straightening Al–Cu–Mg–Ag sheets after their buckling during high-temperature heating for quenching.
Magnetic properties of layered Ni/Cu nanowires
Authors: Bizyaev D. A. , Khairetdinova D. R. , Zagorskiy D. L. , Doludenko I. M. , Panina L. V. , Bukharaev A. A. , Rizvanova A.
Published: April 2024

In this paper, the structural and magnetic properties of layered nanowires (NWs) made of alternating layers of nickel and copper were investigated. NW arrays were obtained by matrix synthesis. The nickel layers had a fixed thickness of 400 nm, and the thickness of the copper layers varied from 25 to 300 nm. The magnetic characteristics of such NWs were studied in two states: in a matrix (integral magnetic characteristics determined using vibrating sample magnetometry) and for individual NW (local magnetization visualized using MFM). For NWs in the matrix, the hysteresis loops measured for the two directions of the magnetic field become identical when the thickness of the Cu layer increases to 300 nm, which is due to the weakening of the dipole interaction between the Ni layers. The coercive force (190 Oe) and the residual magnetization (0.32 Ms) in the parallel direction of the field are maximal for the thickness of the Cu layer equal to 100 nm, which corresponds to the diameter of NWs and the distance between them. The MFM method was used to study samples with Cu layer thicknesses of 300 nm. It is demonstrated step by step how the application of an external magnetic field leads to remagnetization. An intermediate antiparallel distribution of magnetization in neighboring layers is revealed. The magnitude of the coercive force for an agglomerate of two or three NWs varies between 40-50 Oe, but the magnetization switching field turns out to be about 160 Oe, which is comparable to the coercive force for an array of NWs of this type (180-190 Oe). This demonstrates the role of the NWs' dipole interaction in the matrix.
The Effect of High-Temperature Thermomechanical Treatment on the Microstructure
and Mechanical Properties of Cu–Al–Ni–(B) Alloys with a Thermoelastic Martensitic Transformation
Authors: Svirid A. E. , Pushin V. G. , Makarov V. V. , Kuranova N. N.
Published: April 2024

Polycrystalline boron-alloyed α + β Cu–Al–Ni compositions subjected to high-temperature thermomechanical treatment (HTMT) via forging and rolling are studied for the first time. Optical, scanning, and transmission electron microscopy and X-ray diffraction analysis were used in combination with measurementsof tensile mechanical properties to study the peculiarities of the microstructure, phase composition, and mechanical properties of these alloys. The peculiarities of the microstructure and mechanical behavior of alloys differing in their aluminum and boron contents, which were subjected to HTMT, have been determined.The alloys were prepared in the fine-grained state, which determines the increase in the functional strength and plastic characteristics. A schedule of HTMT of bulk Cu–Al–Ni–(B) alloys is proposed.
The Metallographic Study of High-Speed Deformation and Convergence of Thick-Walled Cylindrical Copper Shells under Explosive Loading
Authors: Ze’dovich V. I. , Kheifets A. E. , Valushkin S. V. , Belyakov V. I.
Published: April 2024

Abstract—Metallographic method investigated the process of convergence of thick-walled cylindrical copper shells under the action of an explosion. The explosion was initiated from eight points evenly spaced in a circle on the surface of the explosive surrounding the shell. At the intermediate stage of convergence, eight outliers formed on the inner surface of the shell. The convergence of the shells into the cylinder is completed by expanding and closing the emissions. The formation of outliers is explained by the occurrence of plastic (cumulative) jets at the deformation front. Jets occur when adjacent deformation projections collide. Areas of localized deformation were found inside and around the ejections, which is associated with this method of initiating an explosion. It is established that high-speed deformation of copper during the convergence of shells is accompanied by the formation of a large number of twins. There are more twins in the outer zones of the shells than in the inner ones.
Structure and magnetic properties of Gd2O3 nanoparticles obtained by the spark discharge method
Authors: Svalov A. V. , Beketov I. V, , Maksimov A. D. , Medvedev A. I. , Neznakhin D. S. , Arkhipov A. V. , Kurlyandskaya G. V.
Published: April 2024

Gadolinium oxide nanoparticles were obtained by the spark discharge electrophysical method. Structure, magnetic and magnetocaloric properties of Gd2O3 nanoparticles are comparatively analyzed. According to X-ray phase analysis, the synthesized Gd2O3 nanoparticles contain two crystallographic phases: cubic and monoclinic. The change in the magnetic part of the entropy dSM was determined from the measurement data of magnetic isotherms based on the Maxwell relation. The maximum value of dSM for a magnetic field variation amplitude of 2 T was approximately 17 J/kgK and was observed at a temperature of 2.5 K.
Mechanical Properties of High Entropy Alloys Based on Rare Earth Elements with Yttrium and Scandium
Authors: Sipatov I. S. , Korolev O. A. , Ignatieva E. V. , Marshuk L. A. , Gelchinskiy B. R. , Rempel A. A.
Published: April 2024

Abstract—The high-entropy alloys GdTbDyHoSc and GdTbDyHoY having equiatomic composition are considered as promising materials for magnetic cold generators. The results of the alloys structure and chemical composition investigation are presented in this paper. The solidus and liquidus temperatures of the alloys under investigation were determined by the method of differential scanning calorimetry. Based on these data, an experimental mode of thermocyclic treatment was selected. There were no signs of alloys destruction after five cycles testing for heat resistance in the following regime: 15 min exposition at 1073 K (~0.6 of the melting temperature) and subsequent quenching in room temperature water. It was found that the applied heat treatment led to an increase in the hardness of the alloys by 2–3 times and a decrease in wear resistance by 4–40 times, depending on the composition of the alloys and the number of heat treatment cycles. A significant change in the properties of alloys is associated with the formation of oxides of the REM2O3 type not only on the surface of the alloys, but also in their volume, which is due to the high chemical activity of rare earth metals (REM). The presented data will be useful for the development of modes of thermal and thermomechanical processing of various alloys.
The Influence of Technological Parameters on the Structure and Properties of the Selective Laser Melting Al–Cu–Mg–Si Alloy
Authors: Petrova A. N. , Klenov A. I. , Brodova I. G. , Rasposienko D. Yu. , Pilshikov A. A. , Orlova N. Yu.
Published: April 2024

Abstract—Monolithic and bulk-structured samples of different densities were produced by means of selective laser melting on the 3D-metal printer Realizer SLM 100. An evaluation of their quality and structure characterization were carried out. Correlation of parameters of synthesis—intertrack distance and layer thickness at 200 W laser power, and structural characteristics were determined. According to the experimental results, optimal parameters of the synthesis were found for obtaining samples from AK6 alloy with dispersed structure and high mechanical properties. Correlation of the fine structure paramerers of the volume-structured samples with cubic geometry and synthesis parameters were established, types of defects that affect their mechanical properties were determined.
Magnitocaloric Effect in RCO5 (R = Gd, Tb, Dy, Ho) Alloys
Authors: Utarbekova M. V. , Orshulevich M. A. , Bataev D. S. , Fazlitdinova A. G. , Taskaev S. V.
Published: April 2024

Abstract—Experimental studies of magnetic and magnetocaloric properties of polycrystalline RCo5 alloys (R = Gd, Tb, Dy, Ho) in external magnetic fields up to 3 Tesla have been carried out. The results of magnetic measurements have shown that these compounds have small coercivity and reach saturation in small fields. It was found that the magnetocaloric effect in the studied co-compounds is observed in a wide temperature range, and for the intermetallides TbCo5, DyCo5, HoCo5 has several regions of existence, comparable in magnitude of the effect. The presence of several MCE existence intervals is caused by a series of magnetic phase transitions in these ferrimagnetic compounds.
Effect of Field Annealing on Magnetic Properties of Magnetic Soft Iron–Germanium Alloys
Authors: Lukshina V. A. , Timofeeva A. V. , Shishkin D. A. , Gornostyrev Yu. N. , Ershov N. V.
Published: April 2024

Abstract—The concentration dependence of the magnetic properties of iron–germanium alloys before and after thermomagnetic treatment, which represents an annealing of alloy samples in the ferromagnetic state in a permanent or alternating magnetic field (magnetic field annealing – MFA), has been investigated. It is shown that before MFA, with an increase in the germanium content in the range of 3–30 at % Ge, the coercive force increases and the residual induction decreases. As a result of thermomagnetic treatment, in the alloy samples magnetic anisotropy is induced: the magnetic hysteresis loops become narrower, the residual induction increases, and the coercive force decreases. Thermomagnetic treatment is effective for Fe–Ge alloys with a germanium content from 6 to 18 at %, and its highest efficiency is observed at 12 at % Ge. Features of the structural state of iron–germanium alloys and their role in the formation of magnetic properties during annealing in a magnetic field are discussed.
Effect of Titanium Diselenide Doping on the Magnetic State and Transport Properties of FeTe
Authors: Kislov E. , Selezneva N. V. , Sherokalova E. M. , Volegov A. S. , Kuznetsov D. K. , Baranov N. V.
Published: April 2024

Abstract—The iron–tellurium-based compounds Fe1.1Te(TiSe2)y doped with titanium diselenide (y = 0, 0.04, 0.08, 0.1, 0.2) have been synthesized for the first time and studied by means of x-ray diffraction, electrical resistivity and magnetization measurements. It has been shown that the addition of a small amount of titanium diselenide to single-phase iron telluride with a tetragonal crystal structure leads to the appearance of superconductivity, a decrease in the Néel temperature and contraction of the crystal lattice at y ≥ 0.04. The maximal temperature of the onset of the superconducting transition \(T_{{\text{c}}}^{{{\text{onset}}}}\) ~ 13 K is observed for a sample with the nominal composition Fe1.1Te(TiSe2)0.1. The behavior of the resistivity with temperature below Tconset is observed to depend on the current value, which may indicate superconductivity characteristic of granular superconductors.
Atomic Structure of Ti2NiCu Alloy after Severe Plastic Deformation by High Pressure Torsion and Heat Treatment
Authors: Kuranova N. N. , Makarov V. V. , Pushin V. G.
Published: April 2024

Abstract—The results of a comparative analysis of the structure of Ti2NiCu alloy subjected to severe plastic deformation by high pressure torsion (HPT) and subsequent annealing are presented. The study of the structure was carried out by diffractometry of electron, X-rays and neutrons, transmission electron microscopy. It is established that an amorphous-crystalline state is formed in the alloy: nanocrystallites with a B2 lattice are present in the amorphous matrix. The analysis of diffuse maxima showed that the topological and compositional near atomic order of nanodomains with a superstructure ordered by type B2 and L21 is present in the Ti2NiCu alloy after HTP on 5 rev.