Composite Element Research Articles

Impact of geometric features of impermeable discrete bedform on hyporheic exchange

The bedform-driven hyporheic exchange plays a crucial role in mass transport within natural aquatic ecosystems like streams and rivers. This study aimed to unveil the impact of geometric features of impermeable discrete bedforms on hyporheic exchange by experimentally measuring quantitative hyporheic exchange flux data and variation characteristics in an annual flume. The experiments encompassed diverse conditions involving the ratio of bedform wavelength (λ) to wave height (h) and relative submergence. The study also analyzed the dependence of the effective diffusion coefficient on the geometric characteristics of bedform composition elements. The experimental results showed that, in comparison to a permeable flat bed, the presence of an impermeable discrete bedform tended to either attenuate or enhance hyporheic exchange, contingent on the geometric characteristics of bedform composition elements. The hyporheic exchange flux exhibited an initially increase followed by a decrease with increasing λ/h, with turbulence penetration emerging as the dominant mechanism governing hyporheic exchange for cases with relatively denser bedform composition elements (e.g., λ/h = 4.0). The effective diffusion coefficient peaked at λ/h around 6.0–8.0, owing to a significant augmentation in the relative contribution of pumping exchange to gross hyporheic exchange. Furthermore, the hyporheic exchange intensity generally increased with decreasing relative submergence, primarily attributed to the augmented relative contribution of pumping exchange to gross hyporheic exchange.

Frame Composition – Features and Elements

The article is a review of the book “Frame composition - characteristics and ele-ments”. The paper analyzes the rational laws and rules of composition in film, televi-sion and photography. Emphasis is placed on the methods that exist for applying the characteristics and compositional elements of a shot. Undoubtedly, one of the most used methods is the principle of the figure-base relationship established by Gestalt psychology. Cinematic composition determines the purpose and meaning of the visual image. This is what composition in cinema and in any of the visual arts is based on. Composition in cinema and photography is an art and its assessment is subjective but based on common elements and patterns by which people perceive images. Objective assessment of the research results in the dynamics of development and the impact of the effect on the film, television and photographic frame.

Zen in Early Persian Painting—A Study of the 1314–1315 Jāmiʿ al-Tavārīkh Illustrations

Since the establishment of the Ilkhanid Dynasty, Chinese painting has exerted a profound influence on various facets of Persian painting. This influence facilitated the divergence of Persian painting from Arab painting, fostering the gradual formation of an independent style. To explore whether Zen painting, which has been highly influential in contemporary China, also played a role in shaping Persian painting, this article first discusses the possibility that Zen books and Zen paintings were introduced to the Ilkhanid Dynasty. Subsequently, it delves into the illustrations of the Jāmiʿ al-Tavārīkh dating back to 1314–1315, analyzing Zen elements through three lenses: theme, brushwork, and compositional elements. Through this analysis, the article aims to provide insights into the impact of Chinese Zen art on Persian painting, offering a fresh perspective for scrutinizing the broader Chinese influence on Persian art.

East Greenland Prograded Margin and Oceanic Composite Tectono-Sedimentary Element, offshore East Greenland

Abstract The East Greenland Prograded Margin and Oceanic Composite Tectono-Sedimentary Element (EGPMO CTSE) consists of the East Greenland Prograded Margin Tectonic-Sedimentary Element (TSE) and the East Greenland Oceanic (EGO) TSE located over continental and oceanic crust, respectively. The East Greenland Prograded Margin TSE (EGPM TSE) is made up of six segments, with their basal part deferring from Maastrichtian to Miocene in age. The variation reflects the different timing in transition from syn- to post-rift, controlled by the lateral migration of rifting and diachronic continental break-up in the northern North Atlantic. The post-rift history can be subdivided into a pre-break-up Maastrichtian–Paleocene post-rift phase developed entirely offshore NE Greenland and an earliest Eocene–Miocene syn- to post-break-up phase developed in the wake of progressive continental rupture. Finally, the CTSE started to develop as a unified body from Miocene time after the complete separation of Greenland from Eurasia and the Jan Mayen microcontinent. The EGO TSE has formed since the earliest Eocene commencement of seafloor spreading. The structural and depositional outline of the EGPMO CTSE depicts its tectonic history but also reflects phases of volcanism, denudation and intensified icehouse conditions since the middle Miocene that were triggered by the opening of the Fram Strait and the uplift of East Greenland. The first major northern hemisphere glaciations started in NE Greenland. Glaciations expanded southwards during the late Miocene as the Denmark Strait was transgressed and cold surface water from the high arctic started flowing along SE Greenland, cooling the region. The petroleum potential of the EGPM TSE is conceivably modest but a potential exists locally offshore northern NE Greenland where hydrocarbons sourced mainly from the Jurassic–Cretaceous section may have charged structures cored by Maastrichtian–Eocene sandstone reservoirs sealed by overlying marine mudstones.

A simplified method for thermal buckling verification in steel–concrete composite elements

This paper delivers a comprehensive analysis of the thermomechanical behavior of steel–concrete (SC) composite elements under elevated temperatures, up to 200 °C, as these can be encountered in accidental scenarios within nuclear power plant operations. The focus lies on the thermal buckling of external thin steel plates. We undertake an integrated approach, combining an experimental campaign and numerical simulations, to investigate thermal buckling phenomena. Using these findings, along with principles from thermoelasticity and thin plate theory, we establish an analytical model to guide preliminary SC element design. The efficacy of this model is ascertained through rigorous comparisons with experimental and numerical results. The paper concludes by demonstrating the model’s practical utility for thermal buckling verification through a relevant case study.

ВТРАЧЕНІ ЕЛЕМЕНТИ АРХІТЕКТУРНИХ ПАМ’ЯТОК КИЄВА УКРАЇНСЬКОГО БАРОКО

The article is dedicated to the research of the loss of important architectural and compositional elements in Kyiv architectural monuments of the Ukrainian Baroque of the XVIIth – XVIIIth centuries. The author analyzes the architectural development of such Kyiv buildings as the Onufriivska Tower and the Church of Conception of Ann of the Kyiv-Pechersk Lavra, the Resurrection Church, the st. Illia Church, the Temple of Nikolas, the Intercession Church, the Old Building of the Kyiv-Mohyla academy, cookhouse and Church of the Holy Spirit of the Brotherly Epiphany Monastery, St. Sophia Cathedral, Church of the Ascension of the Phlor’s Monastery. All these objects have common destiny because of loss of their important Baroque details during XVIII–XIX centuries. Instead, they gained the forms of other styles, which did not detract from the national signs of these monuments. Such changes were made for various reasons: changes in fashion and styles in architecture, functional and utilitarian needs. However, such transformations were often anti-Ukrainian in nature, and they even ended up replacing Ukrainian symbols with Moscow ones. Let us highlight this very incident with the butt of the story: the reconstruction of the St. Sophia Cathedral in 1882. This unique monument and shrine was adorned with characteristic elements of the Ukrainian Baroque – sloping pediments on western and eastern façades. In fact, the temple was redecorated with elements of Byzantine and Russian architecture. During the Soviet time, the practice of replacing Ukrainian architectural symbols with Russian ones continued. Let us illustrate this with the example of the Ascension Cathedral of the Phlor’s Monastery in Podil. For a long time, researches did not pay attention on such a facts, but now it is time to restore justice to our national symbols. In the author’s opinion, today it is necessary to carry out in-depth research on historical monuments with a view to developing a concept and developing large-scale restoration projects that would restore their original beauty and completeness.

Patriotic principles in the work of M.A. Sholokhov

The article is devoted to the understanding of patriotism according to M.A. Sholokhov. The theme of love for the Motherland is consistently considered in the works of various periods of the famous Soviet writer's work. Being a direct participant in the fateful events for the USSR, Sholokhov managed to reflect patriotism as a multilevel and, at times, contradictory concept. The analysis of the patriotic model of behavior on the example of the main characters and supporting characters of the writer's works is considered in the context of such plot and compositional elements as binary oppositions (good - evil, truth – lies, honor – inhumanity, mercy – cruelty, personal – collective). The description of this concept is accompanied by an appeal to the categories of space and time, an understanding of the ideological, moral and spiritual dominants that guide the literary heroes of the works. Patriotism, presented in the historical context of M.A. Sholokhov's literary heritage, should be considered as a constant that contributes to the reflection of the character and registers the internal logical connections of this constant, its meaningful content throughout the plot. The patriotic paradigm of the worldview of the writer's artistic works is characterized not only by the ability to motivate sacrificial acts, but also by the prerequisite to form the basis for a conflict of personalized positions and views. Using the example of the heroes of his works, M.A. Sholokhov shows us, the readers, what a true patriot should be. It is stated that the artistic heritage of the Master in modern socio-political realities can successfully contribute to the patriotic education of Russian youth, since fiction has a serious impact on the upbringing of a personality, on its inner potential and the choice of moral and ethical guidelines, and contribute to the formation of high moral qualities of a person.

Shear strengthening of existing concrete beams using Fiber Reinforced Concrete

The improvement of repairing and/or strengthening techniques of existing reinforced concrete structures is a subject of interest in the field of Civil Engineering regarding that a great percentage of civil works involves interventions on existing structures. This research is in the frame of an experimental ongoing program aimed at studying strengthening techniques of concrete structural elements both at ambient temperature and after the exposure to high temperatures. This paper is particularly focused on the shear strengthening of existing reinforced concrete beams using a well-known technique as concrete jacketing but employing a high-performance concrete type. The results of an experimental campaign related with reinforced concrete beams strengthening with jackets elaborated with Self-Compacting Fiber Reinforced High Strength Concrete (SCFRHSC) are addressed. Different jacket widths, concrete jacket types and surface preparations are considered. The experimental program includes Three-Point Bending (TPB) tests on jacketed Reinforced Concrete beams and also other mechanical tests on laboratory scale samples: uniaxial compression and splitting tensile tests on cylindrical samples and TPB on notched prismatic specimens. A comparison between traditional jacketing with reinforced concrete and jacketing using SCFRHSC without steel reinforcing bars is presented. The results show that the considered high-performance concrete is a suitable material for strengthening existing beams with thinner concrete jackets than those necessary using standard concrete and therefore, resulting in a composite element with better sustainability properties.

Optimal bilayer composites for temperature-tracking wireless electronics.

Modern silicone-based epidermal electronics engineered for body temperature sensing represent a pivotal development in the quest for advancing preventive medicine and enhancing post-surgical monitoring. While these compact and highly flexible electronics empower real-time monitoring in dynamic environments, a noteworthy limitation is the challenge in regulating the infiltration or obstruction of heat from the external environment into the surface layers of these electronics. The study presents a cost-effective temperature sensing solution by embedding wireless electronics in a multi-layered elastomeric composite to meet the dual needs of enhanced thermal insulation for encapsulation in contact with air and improved thermal conductivity for the substrate in contact with the skin. The encapsulating composite benefits from the inclusion of hollow silica microspheres, which reduce the thermal conductivity by 40%, while non-spherical aluminum nitride enhances the thermal conductivity of the substrate by 370%. The addition of particles to the respective composites inevitably leads to an increase in modulus. Two composite elements are engineered to coexist while maintaining a matching low modulus of 3.4 MPa and a stretchability exceeding 30%, all without compromising the optimized thermal properties. Consecutive thermal, electrical, and mechanical characterization confirms the sensor's capacity for precise body temperature monitoring during a single day's lifespan, while also assessing the influence of behavioral factors on body temperature.

Plant Soup Formulations Show Cholinesterase Inhibition Potential in the Prevention of Alzheimer's Disease.

As the cholinesterase theory is a prominent hypothesis underlying our current understanding of Alzheimer's disease (AD), the goal of this study was to compose functional vegan lunchtime soups with potential health benefits in the prevention of AD (in the context of cholinesterase inhibition). The potential of 36 edible plant raw materials in terms of acetyl- and butyrylcholinesterase inhibition was investigated using a 96-well microplate reader. The most promising ingredients were combined to obtain 18 palatable vegetable soup recipes with 6 dominant flavor, appearance, and aroma variants. To shortlist candidates for in-depth analysis and potential consideration in industrial production, our team performed a sensory analysis of the soups. The white boletus soup exhibited the highest potential for cholinesterase inhibition, further bolstered by the inclusion of other ingredients known for their elevated capacity to inhibit both AChE and BChE. Ingredients such as blackthorn (Prunus spinosa), garlic, and white potato contributed significantly to this inhibitory effect (nearly 100% of AChE inhibition). Notably, intriguing results were also observed for asparagus soup, despite the fact that the inhibitory potential of asparagus itself is negligible compared to other raw materials. The success of the asparagus soup lies in the meticulous selection of various ingredients, each contributing to its overall effectiveness. It was observed that mushroom soups scored the highest in this respect, while the team members' response to nettle soup was the least favorable. The outcomes of our study should serve as a catalyst for further exploration of this important research domain. Our current research focuses on deeper insights into the potential of comprehensive meal options. Furthermore, the synergy/antagonism/non-interaction between respective soup ingredients as well as elements of individual soups' chemical composition is a very interesting topic currently under our intensive scientific investigation.

Exploring the Influence of Yogic Asana Practice on Body Fat Percentage - A Systematic Review

Yoga is a spiritual, mental, and physical discipline-based activity practiced thousands of years ago and originated in India. Yoga is a science-rich unique holistic approach focusing on mind and body harmony. Exercise neuroscientists and physiologists long acknowledged the health benefits of physical postures, meditation and breathing exercises. However, recent research has demonstrated that breathing and meditation practices also provide active attentional benefits. Scientific evidence-based research on yoga creates interest among the research fraternity. This article highlights the current understanding of yoga asanas and their documented positive impacts on body fat percentage. The author reviewed more than 13 studies and articles about the effects of yogic asanas practice on body fat percentage. All the studies reveal the positive impact of yogic asanas (physical posture) on the different elements of body composition. The studies offer promising evidence that yogic asanas practice may hold promise to mitigate body fat percentage along with other body composition elements.

Resistência ao cisalhamento longitudinal de lajes mistas modeladas em escala real considerando a geometria das mossas por meio do método dos elementos finitos

Abstract Slabs with cast-in-place steel formwork are composite structural elements composed of concrete and steel. The horizontal shear failure mode is the most common in composite slabs based on numerous experimental studies. This failure mode consists of loss of adherence and mechanical contact at the interface of the composite system and often occurs before the system reaches its full bending capacity. Thus, the design of this constructive system is determined by the value of the longitudinal shear strength, which can be computed by the semi-empirical so-called traditional m-k method based on the four-point bending test proposed by several standards. One of the most known factors to influence the longitudinal shear strength is the geometry of embossments present in the steel work. Calibrated computational simulation using the finite element method can be an alternative way to simulate this type of test. The present work modified and adapted a methodology explicitly including the geometry of embossments in the analysis in order to use materials and products with characteristics available to structural engineers in Brazil and used this methodology to derive m-k coefficients. This is being made with the objective of numerically simulating the effect of relevant parameters for determining the longitudinal shear strength at the concrete-steel interface of composite slabs. Force versus slip, force versus displacement graphs were obtained and the m-k coefficient values found were compared with those of other authors in the literature. The simulations presented values consistent with the literature and in relation to the rupture mode by longitudinal shear, the numerical simulations performed presented ultimate strengths with goodness-of-fit measured by the conventional coefficient of determination, reaching a good value for the semi-empirical relation using the results of the finite element data.

The Effect of Layer Orientation on the Behaviour of the Multilayered Composite Plates

In recent years, the composite materials have been increasingly used in various industries. The required knowledge, which is necessary in order to be able to use composite materials, composite structural elements, requires FEM numerical simulations. In this paper, the study of the effect of the layer orientation on the behavior of the multilayered composite plates is study by taking the three-layer laminate composite for different type of laminates with different symmetric and unsymmetric orientation of the lamina: 0/90/0, 90/0/90, 45/-45/45, -45/45/-45, 0/45/90, 0/-45/90, 90/45/0, 90/-45/0. Based on the obtained results, it can state that the emergence of displacements is dependent on the ply orientation. The used models do not give the same results of the maximum values of the vertical displacement of the layered laminate composite plates.

Zalety materiałów kompozytowych stosowanych w otworowych narzędziach skrawających

One of the important reserves for the growth of oil and gas production is the acceleration of emergency recovery work in production and exploration wells at minimal cost. A significant amount of work in downhole conditions is performed using downhole destructive and cutting tools. Each oil and gas producing country annually uses more than 100 standard sizes, thousands of cutting tool sets: downhole, annular, combined, pilot, internal and external pipe cutters, as well as reamers for cutting side “windows” in production strings. Therefore, the need for them is growing significantly every year. The conducted experiments show that during the operation of cutting tools, the working abrasive-cutting part of the tool wears out and collapses, but the body, other elements and the connecting thread remain suitable for further operation. Therefore, the restoration of working bodies, consisting of crushed particles of used borehole cutting tools, is an urgent scientific and technical task for the oil and gas industry. When repairing oil and gas wells, as well as eliminating the most complex accidents, more than a hundred standard sizes of downhole cutting and destructive tools are used. Currently, an acute shortage of this equipment in oilfield facilities makes it necessary to reconsider the technologies for restoring downhole cutting and destructive tools and introduce them into production. The conducted studies show that there is not enough information about the thickness and height of the layers of the material applied to the damaged area of the cutting and destructive tool, as well as the information necessary for the optimal mode of its operation and its effectiveness after restoration. Composite materials are widely used in the preparation of cutting-chopping and destructive elements of oil-field tools and equipment used in the drilling, operation and repair of wells. In order to increase the cutting capacity of the cutting part of the tool, it is necessary to investigate the advantages of tungsten-carbide (TC) type composite materials compared to other materials and ensure their resistance to high temperatures. As a result of theoretical studies, the stress-deformation state of the contact areas of the composite elements, where the working areas of the cutting and destructive tools are reinforced, and the dependence of the productivity of the composite materials on the speed of transition to metal and the sizes of the composite grains were determined by using the finite element method (two-dimensional simplex elements).

Heritage identity and Indigenous language learning motivation: A case of Indigenous Taiwanese high school students

AbstractThis study responds to calls to reexamine the L2 motivational self system framework in order to understand motivations to learn languages other than English. Specifically, we explore Indigenous Taiwanese students’ heritage language learning motivation from a possible selves perspective. Following work on the rooted L2 self, the construct of the Indigenous heritage self is incorporated to capture the passion and conviction that motivates learners to maintain language use and revitalize cultural legacies. A nationwide questionnaire survey was administered to 293 indigenous Taiwanese high school students (aged 15–18). Exploratory factor analysis points to the need to include the Indigenous heritage self in an account of the motivation to learn endangered Indigenous languages. The composite elements of the Indigenous heritage self consist of goals focused on preserving the Indigenous language and cultures, as well as an emotional attachment to the heritage culture. Furthermore, multiple regression results show that learners’ Indigenous heritage self and ideal future self are significant contributors to motivational intensity and classroom engagement. Findings indicate that community‐based motivation is equally important as individual learners’ idealized future images in motivating Indigenous language learning. The article concludes by suggesting curriculum initiatives that incorporate motivational strategy instruction aimed at developing an ideal self for speaking the Indigenous language, bridging classroom content and the cultural immersive experiences that students have outside formal environments.

Effects of long-term high temperature annealing on Li2TiO3 and advanced core-shell Li2TiO3-Li4SiO4 tritium breeders

The present work investigates the evolution of mechanical performance and provides a comprehensive study of the changes in microstructure, phase, and compositional elements of Li2TiO3 and core-shell Li2TiO3-Li4SiO4 pebbles resulting from annealing at 900 °C in He incl. 0.1 vol % H2 flow atmosphere for specific durations. Compression tests show that long-term annealing improves the mechanical performance of Li2TiO3 instead of degrading it. The mean crush load of Li2TiO3 increases from 41 N to 45 N after 1000 h of annealing. Li2TiO3 pebbles can maintain their microstructure stability, with only limited grain growth and a decrease in open porosity identified. These changes are believed to be responsible for the improvement in mechanical performance after 1000 h. The mechanical performance of core-shell Li2TiO3-Li4SiO4 pebbles primarily degrades during the initial 100 h, with a decrease in mean crush load from 118 N to 91 N. Subsequently, it gradually stabilizes with a mean crush load of 91 N over the remaining annealing period. An increase in open pores and slight Li4SiO4 grain growth was observed after 1000 h of annealing, which is the primary cause of the mechanical performance degradation in core-shell Li2TiO3-Li4SiO4 pebbles. The loss of lithium in core-shell Li2TiO3-Li4SiO4 pebbles is a combined effect of the Li2TiO3 phase and Li4SiO4 phase, with a stronger association to the Li4SiO4 phase.

Detection and Quantification of Conjugative Transfer of Mobile Genetic Elements Carrying Antibiotic Resistance Genes.

Multidrug resistance, due to acquired antimicrobial resistance genes, is increasingly reported in the zoonotic pathogen Streptococcus suis. Most of these resistance genes are carried by chromosomal Mobile Genetic Elements (MGEs), in particular, Integrative and Conjugative Elements (ICEs) and Integrative and Mobilizable Elements (IMEs). ICEs and IMEs frequently form tandems or nested composite elements, which make their identification difficult. To evaluate their mobility, it is necessary to (i) select the suitable donor-recipient pairs for mating assays, (ii) do PCR excision tests to confirm that the genetic element is able to excise from the chromosome as a circular intermediate, and (iii) evaluate the transfer of the genetic element by conjugation by doing mating assays. In addition to a dissemination of resistance genes between S. suis strains, MGEs can lead to a spreading of resistance genes in the environment and toward pathogenic bacteria. This propagation had to be considered in a One Health perspective.

Interpretation of technical and expression aspects on Mauro Giuliani’s “Grand Overture, Op.61”

The Mauro Giuliani’s “Grand Overture, Op. 61” poses a diverse and intricate task for classical guitar musicians, as it involves a complex interweaving of technical elements, profound emotional expression, and intricate structural components. The significant of this study is to acquire a more profound comprehension of the dynamic correlation between composition and artistic interpretation within the framework of this renowned classical guitar composition. There are two research objectives in this study. The first is to interpret the various elements of “Grand Overture, Op. 61” in terms of its composition, encompassing its challenging technical aspects, profound emotional depth, and intricate structural intricacies. The second is to interpret how these facets impose specific artistic expectations on the performer. This study was conducted within the paradigm of artistic research. The data collection technique employed in this study will involve a combination of library research, personal experience, direct observation, and self-reflection. The artistic processes and revelations in this study emphasize the resolution of technical challenges, the development of an approach to achieve a high level of technical proficiency, the analytical examination of compositional elements, and the crafting of sound profiles. These aspects were thoroughly explored through theoretical and practical investigations of “The Grand Overture” by Mauro Giuliani. This ultimately results in the development of distinctive and captivating interpretive decisions that successfully encapsulate the fundamental nature of Giuliani’s composition. The beneficial features of the basic interpretive concepts in this study are highly recommended for future studies to be applied in the form of various classical repertoires and other fields of musical instrumentation.

Memoir essay as a document of fiction

The article explores the memoir essay as a journalistic genre combining documentary and fictional elements. The study is based on the books of memoirs by B. Zaitsev, M. Nesterov and S. Rachmaninov. The analysis of memoir texts by people of creative professions makes it possible to identify the features of the synthesis of two narrative components and to determine the individual author’s approach to the disclosure of the characters’ personality.As a result of the comparative, compositional, stylistic and contextual analysis, we have come to the following conclusions: the artistic and journalistic portrait essay fully retains its genre features only in B. Zaitsev’s book “The Distant Land“, the books of two other authors contain portrait characteristics and sketches as compositional elements in the biographical and autobiographical essay. However, the fictional images created by the memoirists contribute to the strengthening of the documentary nature, vividly, clearly and realistically recreating people and their era, despite the inevitable memoir subjectivism.It is difficult to distinguish between the fictional and documentary sides of the text. In the journalistic text, each of them confirms the dual nature of the essay genre, which is at the intersection of documentary and fictional literature.

Structural-phase transformations of 12% chromium ferritic-martensitic steel EP-823

The features of phase transformations of 12 % chromium ferritic-martensitic steel EP-823 under heating and cooling conditions in the temperature range from 30 to 1100 ℃ were studied by the methods of high-temperature X-ray diffraction analysis (XRD) in situ and differential scanning calorimetry (DSC). According to XRD in situ data, upon heating, the temperatures of the beginning and end of the (α → γ) transformation of ferrite (martensite – austenite) are Ac1 ≈ 880 °C, Ac3 ≈ 1000 °C, respectively. Upon cooling, a diffusion (γ → α) transformation occurs with critical points – Аr1 ≈ 860°С (beginning temperature) and Аr3 ≈ 840 °С (end temperature). According to DSC data, during heating, the critical points of the (α → γ) transformation are Ac1 ≈ 840 °C and Ac3 ≈ 900 °C. During cooling, a martensitic (γ → α) transformation is realized with critical points of the beginning of Ms = 344 ℃ and the end of Mf = 212 ℃ of this transformation. The XRD in situ analysis revealed no precipitation of carbide phases under heating and cooling conditions of steel EP-823. Position of the critical points of phase transformations depends on the research method (XRD in situ or DSC), which is determined by the difference in effective (taking into account the time for shooting in the XRD method) heating-cooling rate. The effect of elemental composition on the position of critical points of phase transformations and the formation of structural-phase states of ferritic-martensitic steels is discussed. It is shown that the increased content of ferrite-stabilizing elements (Cr, Mo, Nb) in composition of EP-823 steel, compared with other steels of the same class, expands the region of existence of the ferrite phase, which can contribute to an increase in the temperature of Ac1 .