Microstructure and mechanical properties of Ti40Nb alloy after severe plastic deformation

The study presents the analysis of microstructure, phase composition and mechanical properties of Ti40Nb alloy exposed to severe plastic deformation. It was shown that isothermal multi-axial forging and further multi-pass rolling intensify the formation of ultra-fine grained structure in the bulk of a billet with the average element size of 0.3 ?m. Such ultra-fine grained structure considerably improves the alloy mechanical properties

Активізація фізичної активності високої інтенсивності чоловіків у літній період складовими способу життя

Topicality. Vigorous and moderate physical activity is an important component of the health of young and middle-aged men. Against the backdrop of a total low-life lifestyle, the activation of vigorous physical activity (VPA) for men by accessible and natural lifestyle components that alter the daily energy balance becomes relevant, taking into account seasonality factors. The purpose of the research is to analyze the effectiveness of the method of natural activation of VPA in young and middle-aged men by correcting the energy balance of the body in the summer season. Research methods: at the first part, the physical condition of men, their physical activity and nutrition were examined on the eve of VPA; the IP calculated the ratio of the number of steps taken to the amount of consumed food grams and the relative weight of the consumed products of animal and vegetable origin; the obtained data were compared with the daily indicators. The result was the individual models of the ID alsow the relative weight of the consumed animal and plant products too. At the second part of the experiment, men were purpose to fully following these models. At the end of experimental we compared the physical state results of men with the initial. Results: the basis of experimental models were the differences between the days before the VPA and the usual ones: IP – 44,58 %, total physical activity – 21,31 %, relative weight of animal products – 14,65 %, relative weight of plant products – 10,62 %, The relative weight of all consumed products is 10.04 %. The basis of the model of the lifestyle of men in the forming experiment was the individual IP − Me = 1,66 steps per gram of consumed food during the day, which was observed by men on the eve of VPA. The method of correction of men’s energy balance on the eve of VPA allowed to increase the number of classes per week of VPA, by 45,89 %; the number of VPA steps by 25,08 %; time taken to take 11,41 %. Positive changes were observed in the physical condition of men too. Conclusions: The developed method of natural activation of VPA of men with lifestyle components, based on simulation of daily energy balance of the organism, proved to be effective. Increasing the body’s energy reserves stimulates the desire for VPA classes the following day in the summer period.Актуальность. Физическая активность высокой и средней интенсивности - важная составляющая здоровья мужчин молодого и среднего возраста. На фоне тотального малоподвижного образа жизни активизация физической активности высокой интенсивности (ФАВИ) мужчин доступными и естественными средствами составными образа жизни, меняющих суточный энергетический баланс, приобретает актуальность, с учетом фактора сезонности. Цель исследования заключается в анализе эффективности метода естественной активизации ФАВИ мужчин молодого и среднего возраста коррекцией энергетического баланса организма в летний сезон. Методы исследования: На первом этапе исследовалось физическое состояние мужчин, их физическая активность и питание накануне ФАВИ; высчитывались ИП соотношение количества пройденных шагов с количеством потребленных граммов пищи, так же относительного веса потребленных продуктов животного и растительного происхождения, данные сравнивались с повседневными показателями. Результатом стали индивидуальные модели ИП с учетом отно­сительного веса животных и растительных продуктов. На втором этапе эксперимента мужчины целенаправ­ленно придерживались данных моделей, по окончании сравнивались показатели физического состояния с начальными результатами. Результаты: основу экспериментальных моделей составили различия между днями накануне ФАВИ и обычными: ИП − 44,58 %, общей физической активности − 21,31 %, относительный вес животных продуктов − 14,65 %, в относительный вес растительных продуктов − 10,62 %, относительный вес всех продуктов − 10,04 %. Основу модели образа жизни мужчин в формирующем эксперименте составили индивидуальные ИП с Ме − 1,66 шагов на грамм потребленной пищи за сутки которого придерживались мужчины накануне ФАВИ. Метод коррекции энергетического баланса мужчин накануне ФАВИ позволил увеличить количество занятий в неделю ФАВИ на 45,89 %; количество шагов ФАВИ на 25,08 %; затраченного времени занятий на 11,41 %. Положительные изменения были отмечены также, в физическом состоянии мужчин. Выводы: Разработанная методика естественной активизации ФАВИ мужчин составными образа жизни, на основе моделирования суточного энергетического баланса организма, оказалась эффективной. Увеличение энергетических запасов организма, в летний период, стимулирует желание занятий ФАВИ на следующий день.Актуальність. Фізична активність високої та середньої інтенсивності – важлива складова здоров’я чоловіків молодого та середнього віку. На фоні тотального малорухомого способу життя активізація фізичної активності високої інтенсивності (ФАВІ) чоловіків доступними та природніми засобами складових способу життя, що змінюють добовий енергетичний баланс, набуває актуальності, враховуючи фактори сезонності. Мета дослідження полягає у аналізі ефективності методу природньої активізації ФАВІ чоловіків молодого та середнього віку корекцією енергетичного балансу організму у літній сезон. Методи дослідження: на першому етапі досліджувався фізичний стан чоловіків, їх фізична активність та харчування напередодні ФАВІ; вираховувались ІП співвідношення кількості пройдених кроків до кількості спожитих грамів їжі та відносної ваги спожитих продуктів тваринного та рослинного походження; отримані дані порівнювались із повсяк­денними показниками. Результатом стали індивідуальні моделі ІП з урахуванням відносної ваги спожитих тваринних та рослинних продуктів. На другому етапі експерименту чоловіки цілеспрямовано дотримувались даних моделей, по закінченню порівнювались показники фізичного стану із початковими результатами. Результати: основу експериментальних моделей констатуючого експерименту склали відмінності між днями напередодні ФАВІ та звичайними: ІП − 44,58 %, загальній фізичній активності – 21,31 %, відносна вага тваринних продуктів – 14,65 %, відносна вага рослинних продуктів – 10,62 %, відносна вага спожитих продуктів – 10,04 %. Основу моделі способу життя чоловіків у формуючому експерименті склали індивідуальні ІП – Me = 1,66 кроків на грам спожитої їжі за добу якого притримувались чоловіки напередодні ФАВІ. Метод корекції енергетичного балансу чоловіків напередодні ФАВІ дозволило збільшити кількість занять на тиждень ФАВІ, на 45,89 %; кількість кроків ФАВІ на 25,08 %; затраченого часу занять на 11,41 %. Позитивні зміни були відмічені у фізичному стані чоловіків. Висновки: Розроблена методика природньої активізації ФАВІ чоловіків складовими способу життя, на основі моделювання добового енергетичного балансу організму, виявилась ефективною. Збільшення енергетичних запасів організму стимулює бажання занять ФАВІ наступного дня у літній період

Assessment of The Impact of Services and Digitalization Level on The Infrastructure Development in Oil and Gas Regions

The relevance and feasibility of studying the problem lie in increasing the investment attractiveness of oil and gas enterprises by activating regional services in mineral resource specialization based on the extensive infrastructure being created. The purpose of this study is to establish a typology for infrastructure services catering to oil and gas enterprises by enhancing the service component and implementing digitalization programs in the regions specializing in mineral resources in Russia. The work substantiates the conceptual foundations of an integrated approach to the formation of infrastructure for economic systems of mineral resource specialization and related services in the form of a synthesis of concepts of reproductive, structural-functional, and systemic approaches. An analysis of the current state of the methodology for implementing a typology of infrastructure services for oil and gas enterprises in the Russian Federation and abroad was carried out. The formation of innovative infrastructure facilities was substantiated through economic modelling of the influence of oilfield services and the level of development of the territory's digitalization on the development of infrastructure facilities in oil and gas regions

Методичні рекомендації до самостійної роботи студентів технічних спеціальностей

Методичні рекомендації до самостійної роботи студентів укладено відповідно до навчальних програм курсу «Вища математика» та «Числові методи» для студентів технічних спеціальностей.Methodical recommendations for students' independent work concluded in accordance with the educational programs of the course "Higher mathematics" and "Numerical methods" for technical students specialties

Latency Estimation Tool and Investigation of Neural Networks Inference on Mobile GPU

A lot of deep learning applications are desired to be run on mobile devices. Both accuracy and inference time are meaningful for a lot of them. While the number of FLOPs is usually used as a proxy for neural network latency, it may not be the best choice. In order to obtain a better approximation of latency, the research community uses lookup tables of all possible layers for the calculation of the inference on a mobile CPU. It requires only a small number of experiments. Unfortunately, on a mobile GPU, this method is not applicable in a straightforward way and shows low precision. In this work, we consider latency approximation on a mobile GPU as a data- and hardware-specific problem. Our main goal is to construct a convenient Latency Estimation Tool for Investigation (LETI) of neural network inference and building robust and accurate latency prediction models for each specific task. To achieve this goal, we make tools that provide a convenient way to conduct massive experiments on different target devices focusing on a mobile GPU. After evaluation of the dataset, one can train the regression model on experimental data and use it for future latency prediction and analysis. We experimentally demonstrate the applicability of such an approach on a subset of the popular NAS-Benchmark 101 dataset for two different mobile GPU

The investigation of the influence of formation conditions on the structure of Ti-40Nb alloy

It was determined that there is components segregation in Ti-Nb alloy under electro arc melting and selective laser melting. It leads to two phase formation. The [beta]-phase forms in the areas enriched in Nb. [alpha]”-phase forms in the Nb-depleted areas. It is recommended to increase the Nb concentration in the alloy up to 45 wt. % to eliminate heterogeneity of phase and elemental composition

Association, Conformational Rearrangements and the Reverse Process of Aggregates Dissociation during Apomyoglobin Amyloid Formation

Amyloid formation is linked with serious human diseases that are currently incurable. Usually, in the study of amyloid aggregation, the description of the protein’s association is in focus. Whereas the mechanism of the cross-β-structure formation, and the presence of aggregation reversibility, remain insufficiently explored. In this work, the kinetics of amyloid aggregation of apomyoglobin (ApoMb) have been studied using thioflavin fluorescence, electron microscopy, and non-denaturing electrophoresis. An analysis of the concentration dependence of the aggregation rates allows the conclusion that ApoMb amyloid formation includes the stages of conformational rearrangements in the aggregates, followed by their association and the fibril formation. The study of the mutant variants aggregation kinetics showed that the association rate is determined by the amino acids’ hydrophobicity, while the rate of conformational rearrangements is affected by the localization of the substitution. An unexpected result was the discovery that ApoMb amyloid formation is reversible, and under native-like conditions, the amyloid can dissociate, producing monomers. A consequence of the reversibility of amyloid aggregation is the presence of the monomer after aggregation completion. Since the aggregation reversibility indicates the possibility of dissociation of already formed fibrils, presented data and approaches can be useful in finding ways for amyloid diseases treatment

Comparative Investigation of the Influence of Ultrafine-Grained State on Deformation and Temperature Behavior and Microstructure Formed during Quasi-Static Tension of Pure Titanium and Ti-45Nb Alloy by Means of Infrared Thermography

A comprehensive study was performed of the deformation and temperature behavior during quasi-static tension, as well as the peculiarities of accumulation and dissipation of energy during plastic deformation. Microstructural analysis at the pre-fracture stage of pure titanium and Ti-45Nb alloy in the coarse grain (CG) and ultrafine-grained (UFG) states was also conducted. It was shown that substructural and dispersion hardening leads to a change in the regularities of dissipation and accumulation energies during deformation of the samples of the pure titanium and Ti-45Nb alloy in the UFG state. Some features of structural transformations during deformation of the pure titanium and Ti-45Nb alloy samples in the CG and UFG states were studied. A band and cellular-network and fragmented dislocation structure was formed in the case of the CG state, while large anisotropic fragments were formed in the UFG state, thus specifying a local softening of the material before fracture

Independent of their localization in protein the hydrophobic amino acid residues have no effect on the molten globule state of apomyoglobin and the disulfide bond on the surface of apomyoglobin stabilizes this intermediate state.

At present it is unclear which interactions in proteins reveal the presence of intermediate states, their stability and formation rate. In this study, we have investigated the effect of substitutions of hydrophobic amino acid residues in the hydrophobic core of protein and on its surface on a molten globule type intermediate state of apomyoglobin. It has been found that independent of their localization in protein, substitutions of hydrophobic amino acid residues do not affect the stability of the molten globule state of apomyoglobin. It has been shown also that introduction of a disulfide bond on the protein surface can stabilize the molten globule state. However in the case of apomyoglobin, stabilization of the intermediate state leads to relative destabilization of the native state of apomyoglobin. The result obtained allows us not only to conclude which mutations can have an effect on the intermediate state of the molten globule type, but also explains why the introduction of a disulfide bond (which seems to "strengthen" the protein) can result in destabilization of the protein native state of apomyoglobin

Severe Plastic Deformation of Mg–Zn–Zr–Ce Alloys: Advancing Corrosion Resistance and Mechanical Strength for Medical Applications

Magnesium-based alloys hold potential for medical applications, but face challenges like rapid bioresorption and limited mechanical strength during early bone healing. In our study, we present a novel Mg–Zn–Zr–Ce alloy with low cerium content (up to 0.1 wt.% Ce) processed using two severe plastic deformation (SPD) techniques. Through an innovative combination of multiaxial forging and multipass rolling, we have achieved a fine-grained structure with an average grain size of the primary α-Mg phase of 1.0 μm. This refined microstructure exhibits improved mechanical properties, including a substantial increase in yield strength (σYS) from 130 to 240 MPa, while preserving ductility. The alloy’s composition includes α-Mg grains, cerium and zinc hydrides, and intermetallic phases with cerium and zinc elements. Tensile testing of the fine-grained alloy demonstrates an enhancement in yield strength (σYS) to 250 MPa, marking a 2.8-fold improvement over the conventional state (σYS = 90 MPa), with a modest 2-fold reduction in ductility. Crucially, electrochemical tests conducted in physiological solutions highlight substantial advancements in corrosion resistance. The corrosion current was reduced from 14 to 2 μA/cm2, while polarization resistance decreased from 3.1 to 8.1 kΩ∙cm2, underlining the alloy’s enhanced resistance to biodegradation. Our results show that the novel Mg–Zn–Zr–Ce alloy, after combined SPD, demonstrates mitigated bioresorption and enhanced mechanical properties. Our findings highlight the fact that the introduction of this innovative alloy and the application of SPD represent significant steps towards addressing the limitations of magnesium-based alloys for medical implants, offering potential improvements in safety and effectiveness