bluuebunny/crossref_metadata_2025 huggingface dataset:
FEATURES OF AIR POLLUTION BY DISPERSED PARTICLES OF THE URBANIZED TERRITORY OF «INNOKAM»
Authors:   Orenburg State University, Orenburg, Russia, Filippov A. A. , Suleimanov I. F. ,   Kazan (Volga region) Federal University, Naberezhnye Chelny, Russia, Yakunin S. N. ,   Orenburg State University, Orenburg, Russia
Published: December 2021

The combination of factors that determine the level of atmospheric pollution, the priority harmful component of which is dispersed particles, has a random and unique character for the urbanized territory of «InnoKam». Therefore, to study the process of atmospheric pollution of this urbanized territory, an approach was used that takes into account that the content in the air of dispersed particles of motor transport and industrial origin depends on the nature of the processes of upsurge, propagation and deposition, which are determined by the fractional composition of particles, structural and functional parameters of road traffic flows., climatic and urban features of the territory and meteorological conditions. The aim of the study is to reveal the patterns of air pollution in the urbanized territory of «InnoKam» with dispersed particles, which is relevant and necessary for the effective implementation of measures to create a favorable and comfortable urban environment, as well as the attractiveness of the innovation and production center for visiting specialists and investors. Regularities of air pollution in the urbanized territory of «InnoKam» by dispersed particles, which is formed when pollution from road traffic flows are superimposed on the polluting background of industrial enterprises, have been investigated. Motor transport streams are both independent sources of the formation of dispersed particles, and a source of upsurge and spread of dispersed particles over considerable distances beyond the boundaries of highways. To reveal the regularities and obtain the corresponding mathematical models, both instrumental methods based on measuring the content of dispersed particles DCh 10 and DCh 2.5 in the atmosphere of the investigated urbanized territory, and statistical analysis of experimental data were used. Mathematical models have been obtained that, with a high degree of reliability, describe the regularities of air pollution by dispersed particles for the urbanized territory of «InnoKam», which is the scientific value of the results obtained. The practical significance of the results obtained lies in their use for predicting and compiling air pollution maps with dispersed particles in all parts of the urbanized territory of «InnoKam» in order to develop and substantiate measures to create a favorable and comfortable urban environment. The main activities are analyzed and divided into three groups, based on the specifics of the sources of formation of dispersed particles (vehicles, traffic flows, highways). The ranking of measures for the effectiveness of reducing air pollution by dispersed particles is the object of further research.
THOUGHT AS A QUASI-POSSIBILITY
Authors:   Ural Federal University named after the first President of Russia B. N. Yeltsin, Yekaterinburg, Russia, Ankin D. V.
Published: December 2021

Modal logic determines a lot in modern metaphysics and ontology, which delve deeper and deeper into the realm of the possible, not limited to the analysis of reality. This makes it relevant to study the problems of philosophical argumentation, built on the basis of modal logic. The aim of the work is to prove that thinkability does not necessarily entail a logical possibility. Because of this, many kinds of modal arguments that involve inference from conceivability to possibility can be flawed. Methodology: the author considers the question of the existence of objects impossible from the point of view of classical logical omniscience as a parallel to the idea of the existence of impossible possible worlds by J. Hintikka. The main idea of this article is the assertion that the gap between conceivability and possibility is generated by the intellectual limitations of the epistemic agent. The agent consistently — within the framework of the information available to him, and not in the absolute sense - considers logically possible that which is logically impossible from the point of view of logical omniscience. It turns out that we are able to think not only of something non-existent (to have empty intentions), but even quite capable of thinking the logically impossible. The conceivability of the impossible is somewhat analogous to the conceivability of impossible objects that are constructed by contemporary artists. The paper draws a parallel between the tautological thinkability of such an equation that is not tautological and the thinkability as a theorem of something that is not a theorem (S. Kripke’s modal arguments). As a particular example, the author criticizes the argument of the zombie by D. Chalmers, which is popular in modern philosophy of consciousness. It is shown that the conceivability of a zombie does not exclude the possible inconsistency of a zombie from an absolute point of view. In the second part, various types of the a priori are also considered, the opposition is built between the classical idea of logical omniscience and the agent-based approach using the categories of semantics of possible worlds. The main result of the proposed work is to prove that both formally contradictory and conceptually contradictory can be outside the framework of the epistemic attainability of the final agent. The author introduces a new philosophical category of the quasi-possible.
HUMAN AND TECHNOLOGY: A NEW ANTHROPOLOGICAL TURN IN CULTURE
Authors:   Moscow Technical University of Communications and Informatics, Moscow, Russia, Pluzhnikova N. N.
Published: December 2021

The relevance of the study is associated with the need for a detailed analysis of the new anthropological foundations in culture in the context of the new sociocultural situation. It the context of the digitalization of culture, in modern philosophy, interest is shifting to the study of technologies and their impact on human life and behavior. Also, the problem of studying the essence of man, his nature and spirituality fades into the background. The aim of the research is to study the processes of transformation of human understanding in the context of human-technology interaction in digital culture, the direct impact of these processes on human perception and behavior. The author analyzes the processes of digitalization of culture. During analyzing the processes of digitalization of culture, the author relied on modern foreign theoretical and applied research, as well as on the hermeneutic method. This research is interdisciplinary, because it combines data from the fields of philosophy, neurophysiology and psychology. The researching is accompanying such factors as: the transformation of a person into a resource for making technological decisions, pseudo-economic positivism, the formation of a model of a schizoid personality, the dominance of neuroscientific explanations in the field of human nature. The author describes a neurobiological model for explaining human behavior, which considers a person in terms of determinism. The result of this model is a deterministic understanding of consciousness. These circumstances allow us to conclude about the delayed effects of the digitalization of culture, one of the essential in which is the ignorance of a person and his spirituality. The author concludes that a significant consequence of the digitalization of culture is a new anthropological turn in the understanding of man and his spirituality. This anthropological turn testifies to the need to return to man and his spirituality, the basis for the study of which will be the creation of a new direction in modern Russian philosophical anthropology, which is of an interdisciplinary nature. In the context of the digitalization of culture, a rethinking of the very concept of a person, the spiritual aspects of his existence in modern society and culture is required.
TOTEM AND TABOO IN THE PENITENTIARY SUBCULTURE
Authors:   Research Institute of the Federal Penitentiary Service of Russia, Moscow, Russia, Ponomarev S. B.
Published: December 2021

The article is devoted to the analysis of the prisons totems and taboos phenomenon. It is shown that the modern penitentiary subculture, as a negative socioregulatory system is characterized by the presence of a complex system of taboos and totems. Researchers of the penitentiary subculture have repeatedly noted the similarities between the primitive and prison communities. This phenomenon is largely due to the fact that under conditions of imprisonment, a person’s outlook narrows, intelligence decreases, and their value orientation changes. The relevance of the study is due to the fact that, despite the presence of a complex system of prison taboos and totems among convicts, as the main manifestations of the penitentiary subculture, a very small number of scientific works are devoted to the genesis and understanding of this phenomenon. The aim of the article is to analyze the phenomenon of prison taboos and totems in the penitentiary subculture. The work shows that for the formation and preservation of a developed system of totems and taboos in the prison environment, a certain critical weight of such indicators as the size of the prison population and the severity of conditions of detention of prisoners is required. An important role in this is also played by such phenomena inherent in being in the penitentiary space, such as chronic stress, a sense of fear and uncertainty. The article reveals the general principles of the formation of prison totems and taboos. At the same time, it is shown that the leading mechanisms for the formation of prison taboos are the techniques of sympathetic and imitation magic. The author’s proposed classification of prison totems and taboos are presented. It is noted that the convict’s adherence to a certain image-totem contributes to his self-identification, determination of his place in the prison social hierarchy, and the formation of a criminal model of behavior. Practical examples of prison taboos and totems are given. It is shown that prison taboos are largely associated with the existence in the social hierarchy of the prison population of castes of «untouchables». The attention of readers is focused on the harshness towards those who violated prison taboos, which can manifest itself in physical punishment, transfer to the lower prison castes, in some cases — the death sentence. The practical significance of the work is the understanding the phenomenon of prison taboos and totems, that can affect the development of measures aimed at combating the manifestations of the penitentiary subculture in places of detention.
Yellow nail syndrome
Authors: Motorina A. V. , Ruksha T. G.
Published: December 2021

Yellow nail syndrome is an extremely rare syndrome, mainly in people over 50 years of age, occurring both systemically and in isolation and requiring the most careful collection of anamnesis, since this condition has a close relationship with respiratory diseases, malignant neoplasms of internal organs and rheumatoid arthritis. Moreover, this rare disease is not sufficiently studied to fully understand its pathogenesis and effective treatment. Patients pay attention to the yellow color of the nails, associated with the deposition of melanin, bile pigments and hemosiderin in the submarginal space, slowing down the growth and thickening of the nail. It should be noted that the change in the nail plates can be observed long before the other clinical manifestations of this syndrome are detected, and probably this can in some cases serve as a harbinger of incipient changes in the lung tissue, neoplasms and changes in the lymphatic vessels. In this regard, it is extremely important to clearly differentiate this condition and refer patients to related specialists for verification of the diagnosis and further treatment.
Experience Professional dermatomycosis of the face, neck and upper part of chest caused by T. mentagrophytes
Authors: Matveeva O. V. , Mikheev G. N. , Sokolovskiy E. V.
Published: December 2021

A 43-year-old female zoologist has an occupational dermatomycosis of the face, neck and upper part of chest caused by T. mentagrophytes. It was mistakenly diagnosed and treated as "Rosacea, papulopustular subtype, ocular rosacea" for 1.5 years. Symmetrical, atypical clinical manifestations with recurrent blepharoconjunctivitis developed as a result of self-treatment using a topical steroid. The detection of cicatrizing folliculitis in the eyebrow area and an arcual peripheral edge in fresh foci on the chest helped to suspect dermatomycosis. The definitive diagnosis was made after the detection of abundant coarse septate mycelium during microscopic investigation of skin scales from foci on the face and chest with 30% KOH and an abundant growth of Trichophyton mentagrophytes during a cultural research study of skin scales, eyebrow hair and eyelashes from lesions. The use of terbinafine for 4 weeks led to the recovery of the patient.
Modern understanding of the pathogenesis of basal cell skin cancer
Authors: Saytburkhanov R. R. , Kubanov A. A. , Kondrakhina I. N. , Plakhova X. I.
Published: December 2021

The incidence of basal cell skin cancer is increasing worldwide. The initiation and progression of basal cell skin cancer is due to the interaction of environmental factors and the patient's genetic characteristics. Aberrant activation of the transmission of the Hedgehog signaling pathway is the main pathogenetic pathway of carcinogenesis.
Since basal cell skin cancer is manifested by significant variability of morphological structure, aggressiveness and response to treatment, the disclosure of the molecular genetics of pathogenesis will become the basis for developing new approaches and increasing the effectiveness of treatment, as well as overcoming tumor resistance to treatment.
To search for the necessary literature, the PubMed, MedLine, Web of Science and RSCI databases were used.
Residential fire risk assessment and management
Authors:   Academy of State Fire Service of EMERCOM of Russia, Tanygina A. A.
Published: December 2021

Introduction. The article analyzes statistical data for the period of 2006-2018 and presents an assessment of fire hazard levels in residential sectors of the constituent entities of the Russian Federation, which were determined on the basis of an integral socio-economic indicator of fire risk. It also considers the problems of assessing fire hazard in the residential sector as in a complex social and economic systems. The purpose of the study is to determine the levels of fire hazard and build a model for managing fire risks in residential sectors of the constituent entities of the Russian Federation. Research methods. To solve the research problems, the methods of system analysis, statistical analysis, mathematical statistics, etc. were used. Research results. A number of statistical dependencies of the fire situation in the Russian Federation have been analyzed and obtained. The indicators with the most fire hazardous level in the residential sectors of the constituent entities of the Russian Federation were determined by calculation. A block diagram of a model for managing fire risks in the residential sector using the integral socio-economic indicator of fire risk (ISEPPR) is built. Conclusion. The values of the fire hazard levels obtained in the work and the model of fire risk management in residential sectors of the constituent entities of the Russian Federation make it possible to improve management decisions in the field of supervisory activities and preventive work of the Federal State Fire Supervision Authorities. Keywords: residential sector, integral socio-economic indicator of fire risk, risk assessment, level of fire hazard
Justification of the power supply system for life support of rescue units and the injured population during field deployment
Authors:   Academy of State Fire Service of EMERCOM of Russia, Sednev V. A.
Published: December 2021

Introduction. Increasing of number, scale and duration of the consequences of emergency situations associated with the violation of the conditions of normal living of people requires the creation of temporary field accommodation points for the affected population and rescue units. At the same time, electric power supply in field temporary accommodation facilities plays a crucial role in the complex of tasks and measures aimed at providing life to the injured population and rescue units. At the same time, there are no mobile autonomous sources of electric energy for providing life support to people in the field in the organizational and staff structure of rescue units, and the existing sources of electric energy in the complexes of equipment used in areas of emergency situations cannot be used for these purposes. Therefore, it is necessary to develop a scientific and methodological approach to determine necessary and sufficient number of sources of electric energy for the power supply of the life support of the injured population and rescue units when they are placed in field temporary accommodation points. The purpose of the study. Electric power supply of field temporary accommodation points for the injured population and rescue units, ensuring the required reliability of electric power supply, maximizing its efficiency in the conditions of possible resource constraints and minimizing the influence of the uncertainty factor in the planning of electricity consumption. Research methods. The main provisions of the calculation of electrical loads, system theory, set theory, probability theory and the apparatus of mathematical statistics. The results of the study. A methodology has been developed that allows to justify the power of electric energy sources for the power supply of field temporary accommodation points for the injured population and rescue units, rational options for the power supply system, the nomenclature and number of electric energy sources for the life support of people in the field; to calculate the electric network; to evaluate the operation of the power supply system, based on the probability of failure-free operation of the source of electric energy; to justify the composition of engineering means to ensure the creation of the power supply system. Conclusion. The scientific and methodological approach for determining the composition of electric energy sources for the power supply of life support for the injured population and rescue units when they are placed in field temporary accommodation points is justified, which also allows to resolve the contradiction between the need to organize the power supply of life support for people in temporary accommodation points and the lack of a reasonable structure of electric energy sources for these purposes. Keywords: temporary accommodation point, injured population, rescue formation, consumers, electric power supply, organization
Testing of metrological parameters of analyzers of explosive gases in laboratory conditions
Authors:   Academy of State Fire Service of EMERCOM of Russia, Chlenov A. N. , Kochegarov A. V. ,   Academy of State Fire Service of EMERCOM of Russia, Aleshkov A. M. ,   Academy of State Fire Service of EMERCOM of Russia
Published: December 2021

Introduction. When training fire safety specialists, it is practically important to acquire skills in assessing the fire hazard of accidents with the release of flammable gases (GG) and vapors of flammable liquids (FL). The task of detecting hazardous concentrations of these substances is performed by gas analysis systems, the main element of which is gas analyzers. Goals and objectives. The aim of the study is to create a gas analysis installation for determining the main metrological characteristics of gas analyzers in a training laboratory. The tasks include the analysis of an existing installation that complies with the current standard, consideration of the design of the test chamber and the methodology for its application for the study of gas analyzers with a diffusion supply of the analyzed medium. The methods include system analysis and mathematical assessment of physical processes occurring in the test chamber during the preparation and conduct of research. Results and discussion. The article proposes and substantiates the design of a laboratory facility, in which a given volumetric concentration of the explosive substance under investigation is created in a special chamber with the help of a dispenser. Mathematical expressions have been obtained to determine the required amount of flammable liquids. The method of preparation of the installation and options for its use for laboratory work are considered. This technique is simple and ensures the safety of industrial gas analyzers research. Conclusions. The article substantiates the design of the gas analysis unit using a special chamber as a source of the gas mixture (GM). A mathematical model of the formation of HMs with a given volumetric concentration of flammable liquids vapors is obtained, based on the Mendeleev-Cliperon equation. The technique of preparing a chamber for determining the metrological characteristics of gas analyzers in a training laboratory is considered. Keywords: explosive gas, gas analyzer, laboratory facility, ideal gas equation, test chamber
Management of personnel of fire and rescue garrisons taking into account radiation exposure
Authors:   Academy of State Fire Service of EMERCOM of Russia, Zavorotnyy A. G.
Published: December 2021

Introduction. At present, despite the efforts made by the state, the state of radiation protection does not reach the level at which there is no unacceptable risk of harm to the life or health of people, the environment, the property of individuals and legal entities, state and municipal property on the territory of the Russian Federation in the event of implementation of radiation treats. The readiness of management bodies, forces and means of fire and rescue garrisons to eliminate the consequences of radiation accidents is a very urgent problem. Goals and objectives. The aim of the work is to improve the management of the personnel of fire and rescue garrisons, taking into account the radiation exposure in preparation for liquidation and during the elimination of radiation accidents. Tasks include the creation and justification of a model that allows you to convert the exit risks of the deterministic effects into the risks of stochastic effects. Methods. To create a model for the management of fire and rescue garrisons’ personnel, taking into account the radiation exposure, we used the literature experimental data and used the probabilistic-statistical method and the method of least squares. Results and discussion. The calculated model of management of the fire and rescue garrisons’ personnel, taking into account radiation exposure in preparation for liquidation and in the course of liquidation of radiation accidents, is developed. The probabilistic mathematical model allows us to estimate the exit of stochastic and deterministic effects depending on the effective radiation dose. The excellent convergence of the predicted (calculated) value EAR1 = 0,000607 and the statistical value EAR0 = 0,000724 is due to the fact that the reference points LD10 = 2 Gy , LD50/60 = 4 Gy , LD90 = 6 Gy are based on repeatedly verified statistical data on radiation accidents and deaths of more than 1000 people in radiation accidents [1]. This indicates that the mathematical model adequately reflects the exit of stochastic and deterministic effects observed during the operation of nuclear facilities both in normal mode and in radiation accidents. Conclusions. The probability of exit of stochastic and deterministic effects depending on the radiation dose received by the personnel of fire and rescue garrisons is presented. The threshold of the stochastic effect for humans is in the vicinity of the equivalent dose of 10 mSv for radiation with low linear energy transfer. At the same time, the probability of a stochastic effect is 3 · 10-6 on average after 15 years. This model of radiation exposure management for the personnel of fire and rescue garrisons could be a good tool for the emergency response manager (fire extinguishing manager) during preparation for the elimination and during the elimination of radiation accidents. Keywords: management, personnel, fire and rescue garrison, radiation exposure, effective radiation dose, risk of death
Ruptured pyomyoma – Rare complication of post-uterine artery embolization: A case report
Authors: Vulasala Sai Swarupa Reddy , Gopireddy Dheeraj Reddy , Mohamed Khaled , Lall Chandana
Published: December 2021

Leiomyomas, also termed as fibroids, are benign smooth, muscle neoplasms seen in 70–80% of women by the age of 50 years. Uterine artery embolization (UAE) is a minimally invasive procedure that involves cessation of vascular supply to the fibroids, by infusion of gelatinous microspheres into the uterine arteries. Pyomyoma is a suppurative leiomyoma, secondary to infection of necrotic tissue. It is an infrequent complication of uterine artery embolization (UAE). Pyomyoma can lead to sepsis, peritonitis, and respiratory distress syndrome resulting in high morbidity and mortality. Due to its rarity, high suspicion is crucial in the diagnosis, and prompt treatment is recommended to reduce mortality. Ultrasound, computed tomography, and magnetic resonance imaging assist in diagnosis. We present a case of a 44-year-old woman with ruptured pyomyoma, following an UAE intervention. The patient was treated with total abdominal hysterectomy and salpingo-oophorectomy along with peritoneal irrigation and drainage.
СОЛИТОНОПОДОБНЫЕ ВОЛНЫ ПРИ ПЕРИОДИЧЕСКОМ ГАРМОНИЧЕСКОМ ВОЗМУЩЕНИИ В ИНТЕРМЕТАЛЛИЧЕСКОМ СОЕДИНЕНИИ СОСТАВА А3В
Authors: Захаров П.В. , Старостенков М.Д. , Янковская У.И. , Дмитриев С.В. , Корзникова Е.А.
Published: December 2021

В данной работе посредством метода молекулярной динамики анализируется поведение приповерхностных слоев в интерметаллиде стехиометрического состава А3В (на примере Pt3Al) при гармоническом внешнем воздействии. Особое внимание уделяется изучению воздействия высокой амплитуды, которые приводят к достаточно быстрому разрушению кристаллической структуры при экстремальных воздействиях. Для описания межатомного взаимодействия используется потенциал, полученный методом погруженного атома. Выявлен механизм, при котором происходит разрушение слоев вблизи поверхности кристалла и показана роль в этом процессе нелинейных локализованных мод. В работе показано, что при продолжительном воздействии флуктуации происходят не только для атомов Al, но и для атомов Pt. Это определяет быстроту разрушения кристаллической решетки вблизи зоны воздействия. Рассмотрена возможность образования уединенных волн в широком диапазоне частот и амплитуд гармонических воздействий. Зависимости, приведенные в работе, позволяют сделать вывод о том, что высокоамплитудные возбуждения могут вносить существенный вклад в процесс накопления энергии вблизи поверхности кристалла. В то же время дальнейшая передача энергии в объемную часть кристалла может осуществляться с помощью нелинейных упругих волн солитонного типа без разрушения материала.
ХАОТИЧЕСКИЕ ДИСКРЕТНЫЕ БРИЗЕРЫ В ТРЕУГОЛЬНОЙ РЕШЕТКЕ ФЕРМИ-ПАСТА-УЛАМА
Authors: Семенов А.С. , Семенова М.Н. , Упадхьяя А. , Дмитриев С.В.
Published: December 2021

Локализация и транспорт энергии в кристаллических решетках активно изучаются в последние три десятилетия. Эти процессы очень важны, поскольку зарождение и движение дефектов кристаллической структуры всегда сопряжено с преодолением потенциальных барьеров, что требует определенной локализации энергии. Большую роль в изучении данных процессов играют методы компьютерного моделирования. К настоящему времени наиболее изученными являются одномерные модели кристаллов – нелинейные цепочки с различным типом межчастичных взаимодействий, в то время как двумерные и трехмерные решетки изучены в значительно меньшей степени. В то же время, хорошо известно, что переход от нелинейных цепочек к нелинейным решеткам большей размерности может приводить к появлению новых физических эффектов. В данной работе анализируется локализация энергии на хаотических дискретных бризерах (ДБ), возникающих в двумерной треугольной решетке в результате развития модуляционной нестабильности делокализованных нелинейных колебательных мод (ДНКМ). Рассмотрены три ДНКМ с частотами выше фононного спектра, демонстрирующие ангармонизм жесткого типа (увеличение частоты колебаний с амплитудой). Хаотические ДБ имеют большое время жизни, медленно излучают свою энергию и в конечном итоге исчезают. Показана эволюция распределения энергии по решетке в ходе развития модуляционной нестабильности всех трех изученных ДНКМ. Наблюдается эволюция макроскопических характеристик решетки при переходе от режима с хаотическими ДБ к тепловому равновесию. Установлено, что ДБ с ангармонизмом жесткого типа приводят к снижению теплоемкости, теплового расширения и жесткости решетки.
ПОЛУЧЕНИЕ И ИССЛЕДОВАНИЕ КРИСТАЛЛОВ СМЕШАННЫХ ГАЛОГЕНИДОВ ДЛЯ НИЗКОФОНОННЫХ ЛАЗЕРНЫХ МАТРИЦ
Authors: Исаенко Л.И. , Елисеев А.П. , Голошумова А.А. , Молокеев М.С. , Тарасова А.Ю.
Published: December 2021

Настоящая работа посвящена выращиванию, исследованию кристаллической структуры и спектроскопических свойств кристаллов смешанных галогенидов (K,Rb)Pb2Cl5 и K0.5Rb0.5Pb2Br5, легированных ионами редкоземельных элементов, в сравнении с тройными аналогами. Эти материалы представляют интерес в качестве кристаллических низкофононных лазерных матриц для эффективного преобразования когерентного излучения в ИК диапазоне. Кристаллы (K,Rb)Pb2Cl5 и K0.5Rb0.5Pb2Br5 были выращены методом Бриджмена (вертикальный вариант). Впервые получены легированные кристаллы состава K0.5Rb0.5Pb2Br5:Er3+. Исследована структура и спектроскопические характеристики выращенных кристаллов. Показано, что кристаллы бромидов прозрачны вплоть до 30 мкм. В легированной матрице K0.5Rb0.5Pb2Br5 ионы Er3+ проявляют интенсивный пик поглощения, что указывает на достаточно высокий коэффициент вхождения редкоземельного иона в структуру смешанного кристалла. Таким образом, кристаллы K0.5Rb0.5Pb2Br5:Er3+ могут рассматриваться в качестве перспективного кристаллического материала для генерации лазерного излучения, однако исследования их функциональных свойств должны быть продолжены.
МОЛЕКУЛЯРНО-ДИНАМИЧЕСКОЕ ИССЛЕДОВАНИЕ ВЛИЯНИЯ ПРИМЕСЕЙ УГЛЕРОДА И КИСЛОРОДА НА СКОРОСТЬ МИГРАЦИИ ГРАНИЦ НАКЛОНА <110> В НИКЕЛЕ И СЕРЕБРЕ
Authors: Зоря И.В. , Полетаев Г.М.
Published: December 2021

Методом молекулярной динамики проведено исследование влияния примесных атомов углерода и кислорода на скорость миграции границ наклона с осью разориентации <110> в ГЦК металлах никеле и серебре. Получены зависимости энергии рассматриваемых границ и скорости их миграции при температуре 0,95∙Tпл от угла разориентации. Показано, что скорость миграции границ наклона <110> при тех же условиях ниже на порядок скорости миграции границ <111> и <100>, что, в первую очередь, обусловлено сравнительно низкой энергией границ <110>. Миграция границ сопровождалась формированием областей одинаковой формы в том зерне, в сторону которого перемещалась граница, повернутых на угол разориентации. Миграция малоугловых границ, как правило, происходила посредством кооперативных сдвигов в результате согласованного скольжения зернограничных дислокаций. Переползание дислокаций, вызванное диффузией, практически не вносило вклад в механизм миграции границ. Введение примесных атомов углерода и кислорода приводило к значительному снижению скорости миграции границ зерен. Для примесных атомов углерода и кислорода рассчитаны энергии связи с зернограничными дислокациями в рассматриваемых металлах. Полученные значения хорошо коррелируют с зависимостями скорости миграции границ <110> от концентрации примесей. Влияние примесей на миграцию границ в Ag оказалось меньше, чем в Ni, что в данном случае объясняется отличием их параметров решетки (4,086 Å и 3,524 Å соответственно), при том, что их электроотрицательности почти одинаковые. Наибольшие эффект примесей на скорость миграции границ и значение энергии связи были получены для системы Ni-C, наименьшие – для Ag-O.
АНАЛИЗ ДЕФОРМАЦИОННЫХ ДИАГРАММ ОДНООСНОГО ЦИКЛИЧЕСКОГО РАСТЯЖЕНИЯ ПРОВОЛОК И МЕТАЛЛАТРИКОТАЖА ИЗ TiNi СПЛАВА
Authors: Марченко Е.С. , Байгонакова Г.А. , Ковалёва М.А. , Гюнтер С.В. , Шишелова А.А. , Гарин А.С. , Ветрова А.В. , Дубовиков К.М. , Мамазакиров О.
Published: December 2021

В работе рассмотрено деформационное поведение тонких TiNi проволок диаметрами 40-90 мкм при одноосном растяжении. Деформационные зависимости напряжение-деформация, полученные в результате эксперимента, полностью соответствуют типовым диаграммам растяжения нитинола и подтверждают наличие мартенситного перехода, вызванного напряжением. Испытания на циклическое растяжение показали, что деформация проволоки характеризуется сверхэластичным поведением. Были получены деформационные диаграммы для металлотрикотажа из проволоки толщиной 60 мкм, и проведен сравнительный анализ с деформационным поведением проволоки. Результаты показали, что при одноосном растяжении металлотрикотажа на деформационных зависимостях отсутствует участок текучести, вызванный мартенситным переходом. Несмотря на сверхэластичное поведение проволок, сам металлотрикотаж, изготовленный из сверхэластисных проволок, ведет себя гиперупруго. Обнаружена закономерность, согласно которой предел прочности металлотрикотажа значительно ниже предела прочности проволоки.
Understanding MOF nucleation from solution with Evolving Graphs
Authors: Kollias Loukas , Rousseau Roger , Glezakou Vassiliki-Alexandra , Salvalaglio Matteo
Published: December 2021

Molecular modeling is ordinarily employed to understand the synthesis of complex materials. In this work, we investigate the collective assembly of building units that have been experimentally observed to initiate Metal-Organic Framework (MOF) nucleation. MOFs exhibit attractive characteristics such as remarkable surface area and diverse porosities, however, a mechanistic understanding of their synthesis and scale-up remains underexplored due to the complicated nature of the building block interactions. Here, we tackle this problem with large-scale molecular dynamics simulations under a variety of synthesis conditions and mixture compositions. We observe that the connectivity of building units, as well as their level of crystalline order and fractal dimension, largely vary depending on the synthesis conditions. However, these properties naturally emerge when interpreting the self-assembly process of MOF nuclei as the time-evolution of an undirected graph. The results show that solution-induced conformational complexity and ionic concentration have a dramatic effect on the morphology of clusters emerging during assembly, such diversity is captured by key features of the graph representation. Principal Component Analysis (PCA) on graph properties successfully deconvolutes MOF self-assembly to be characterized by a small number of molecular descriptors, such as average coordination number between half-secondary building units (half-SBUs) and fractal dimension, which can be followed by time-resolved spectroscopy. We conclude that graph theory can be used to understand complex processes such as MOF nucleation by providing molecular descriptors accessible by both simulation and experiment.
Multiformity of Photoelectron Storages in Functionalized Carbon Nitrides Enabling Reversible and Adaptable Colorimetric Sensing
Authors: Han Dan , Yang Hong , Zhou Zhixin , Wu Kaiqing , Ma Jin , Fang Yanfeng , Hong Qing , Xi Guangcheng , Liu Songqin , Shen Yanfei , Zhang Yuanjian
Published: December 2021

Colorimetric sensing has been widely used for centuries across diverse fields, thanks to easy operation with no electricity and uncompromised high sensitivity. However, the limited number of chromogenic systems hampers its broader applications. Here, we reported that carbon nitride (CN), the raw materials-abundant and cheap semiconductors with photoelectron storage capability, can be developed as a new chromogenic platform for colorimetric sensing. Beyond most photoelectron storage materials that only demonstrated blue color in the excited state, CN could also exhibit brown color by terminal group functionalization. The experiments and DFT theoretical calculation revealed the origin of the unusual two types of color switches. Cyano and carbonyl terminal groups in CN elongated the centroids distance of electron/hole and stabilized the excited states through a physical and electrochemical pathway, respectively; meanwhile, the counter cations strengthened these processes. As a result, the CN-derived colorimetric O2 sensors demonstrated excellent reversibility in recycling hundreds of times for detection, and exhibited adaptable limit of detection and linear detection range, which was superior to commercial O2 sensors, especially for complex systems with broad variable concentrations.
Dispersion Corrected r2SCAN Based Global Hybrid Functionals: r2SCANh, r2SCAN0, and r2SCAN50
Authors: Bursch Markus , Neugebauer Hagen , Ehlert Sebastian , Grimme Stefan
Published: December 2021

The re-regularized semilocal meta generalized gradient approximation (meta-GGA) exchange-correlation functional r2SCAN [J. W. Furness, A. D. Kaplan, J. Ning, J. P. Perdew, and J. Sun, J. Phys. Chem. Lett. 11, 8208–8215 (2020)] is used to create the three global hybrid functionals with varying admixtures of Hartree–Fock exact exchange (HFX). The resulting exchange-correlation functionals r2SCANh (10% HFX), r2SCAN0 (25% HFX), and r2SCAN50 (50%HFX) are combined with the recent semi-classical D4 London dispersion correction. The new functionals are assessed for molecular geometries, general main-group, and metalorganic thermochemistry at 26 comprehensive benchmark sets including such as the large GMTKN55, ROST61, and IONPI19 sets. It is shown that a moderate admixture of HFX leads to overall mean percentual improvements of −11 (r2SCANh-D4), −16 (r2SCAN0-D4), and −1% (r2SCAN50-D4) regarding thermochemistry compared to the parental meta-GGA. For organometallic reaction energies and barriers, r2SCAN0-D4 even yields a mean improvement of −35%. The computation of structural parameters does not systematically profit from HFX admixture. Overall, the most promising combination r2SCAN0-D4 performs well for both main-group and organometallic thermochemistry. It yields deviations better or on par with other very well-performing global hybrid functionals such as PW6B95-D4 or PBE0-D4. Regarding systems prone to self-interaction errors (SIE4x4), r2SCAN0-D4 shows reasonable performance, reaching the quality of the range-separated ωB97X-V functional. Accordingly, r2SCAN0-D4 in combination with a sufficiently converged basis set (def2-QZVP(P)) represents a robust and reliable choice for general use in the calculation of thermochemical properties of both, main-group and organometallic chemistry.
O(N)Stochastic Evaluation of Many-Body van der Waals Energies in Large Complex Systems
Authors: Poir Pier Paolo , Lagardère Louis , Piquemal Jean-Philip
Published: December 2021

We propose a new strategy to solve the Tkatchenko-Scheffler Many-Body Dispersion (MBD) model’s equations. Our approach overcomes the original O(N**3) computational complexity that limits its applicability to large molecular systems within thecontext of O(N) Density Functional Theory (DFT). First, in order to generate the required frequency-dependent screenedpolarizabilities, we introduce an efficient solution to the Dyson-like self-consistent screening equations. The scheme reducesthe number of variables and, coupled to a DIIS extrapolation, exhibits linear-scaling performances. Second, we apply astochastic Lanczos trace estimator resolution to the equations evaluating the many-body interaction energy of coupled quantumharmonic oscillators. While scaling linearly, it also enables communication-free pleasingly-parallel implementations. As the resulting O(N) stochastic massively parallel MBD approach is found to exhibit minimal memory requirements, it opens up the possibility of computing accurate many-body van der Waals interactions of millions-atoms’ complex materials and solvated biosystems with computational times in the range of minutes.
Functionalization and Hydrogenation of Carbon Chains Derived from CO
Authors: Batuecas Maria , Kong Richard , White Andrew , Crimmin Mark
Published: December 2021

Selective reactions that combine H2, CO and organic electrophiles (aldehyde, ketones, isocyanide) to form hydrogenated C3 and C4 carbon chains are reported. These reactions proceed by CO homologation mediated by [W(CO)6] and an aluminum(I) reductant, followed by functionalization and hydrogenation of the chain ends. A combination of kinetics (rates, KIEs) and DFT calculations has been used to gain insight into a key step which involves hydrogenation of a metallocarbene intermediate. These findings expand the extremely small scope of systems that combine H2 and CO to make well-defined products with complete control over chain length and functionality.
Revealing the unknown aspects of initial steps of prenylated flavin mononucleotide biosynthesis – the role of Lys129 in PaUbiX
Authors: Zaczek Szymon , Dybala-Defratyka Agnieszka
Published: December 2021

Background Prenylated flavin mononucleotide (prFMN) is a recently discovered, heavily modified flavin compound. It is the only known cofactor that enables enzymatic 1,3-dipolar cycloaddition reactions. It is produced by enzymes from UbiX family, from flavin mononucleotide and either dimethylallyl mono- or diphosphate. prFMN biosynthesis is currently reported to be initiated by a protonation of the substrate by Glu140. Methods Computational chemistry methods are applied herein - mostly different flavors of molecular dynamics MD, such as Constant pH MD, hybrid Quantum-Mechanical / Molecular Mechanical MD, and classical MD. Results Glu140 competes for a single proton with Lys129 but it is the latter that adopted a protonated state throughout most of the simulation time. Lys129 plays a key role in the positioning of the DMAP’s phosphate group within the PaUbiX active site. DMAP’s breakdown into a phosphate and a prenyl group can be decoupled from the protona-tion of the DMAP’s phosphate group. Conclusions The role of Lys129 in functioning of PaUbiX is reported for the first time. The severity of interactions between Glu140, Lys129, and DMAP’s phosphate group enables an unusual decoupling of phosphate’s protonation from DMAP’s breakdown. Those findings are most likely conserved throughout the UbiX family to the structural re-semblence of active sites of those proteins. Significance Mechanistic insights into a crucial biochemical process, biosynthesis of prFMN, are provided. This study, alt-hough purely computational, extends and perfectly complements the knowledge obtained in classical laboratory experiments.
METASTABLE STATE WITH HIGH ELECTRIC CONDUCTIVITY IN LiNaTaNbO SYNTHESIZED AT HIGH PRESSURE
Authors: Ефремов Вадим Викторович , Палатников Михаил Николаевич , Щербина Ольга Борисовна
Published: December 2021

Представлены результаты исследования сегнетоэлектрического твердого раствора LiNaTaNbO со структурой перовскита, основанного на ниобате натрия и синтезированного в условиях высокого давления и температуры. Методом импеданс спектроскопии в области температур 290 - 800 К были определены значения удельных проводимостей на постоянном токе, энергии активации носителей заряда и реальная часть диэлектрической проницаемости. Показана эволюция температурных аномалий удельной проводимости и диэлектрической проницаемости при термоциклировании. Обнаруженые эффекты связанны со структурными фазовыми переходами, определена температура Кюри. LiNaTaNbOпретерпевает фазовый переход второго рода. Установлено, что в LiNaTaNbO образуется метастабильная фаза, обладающая высокой электропроводностью в области комнатной температуры. При нагреве выше температуры Кюри данная фаза разрушается. Обсуждаются возможные механизмы обнаруженных явлений.

The results are presented of a study of a ferroelectric solid solution LiNaTaNbO with a perovskite structure based on sodium niobate and synthesized under high pressure and temperature. In the temperature range of 290-800 K, the values of the specific conductivity at direct current, the activation energy of charge carriers, and the real part of the dielectric constant were determined by the method of impedance spectroscopy. Evolution of temperature anomalies of specific conductivity and dielectric constant during thermal cycling is shown. The observed effects are associated with structural phase transitions, and the Curie temperature is determined. The LiNaTaNbO undergoes a second-order phase transition. It was found that a metastable phase is formed in LiNaTaNbO, which has a high electrical conductivity at the room temperature. When heated above the Curie temperature, this phase is destroyed. Possible mechanisms of the discovered phenomena are discussed.
IMPROVING THE EFFICIENCY OF THE CONTACT FORCE METHOD OF THE ATOMIC FORCE SPECTROSCOPY
Authors: Кузнецова Юлия Васильевна
Published: December 2021

Предложена методика, оптимизирующая метод контактной силовой спектроскопии. С помощью макроязыка, интегрированного в программное обеспечение NOVA установки сканирующего зондового микроскопа Solver P47, был разработан алгоритм, позволяющий анализировать силовые кривые, не покидая его основного интерфейса. Апробация метода выполнена на образцах синтезированного полимера, поскольку одним из важнейших механических свойств, определяющим их спектр областей применения, является упругость. В работе получены локальные значения модуля Юнга на поверхности полимера методом контактной силовой спектроскопии с применением скрипта YUNG, разработанного с помощью макроязыка, интегрированного в программу управления сканирующего зондового микроскопа. Показано, что применение скрипта YUNG позволяет оптимизировать метод контактной силовой спектроскопии по поиску показателя степени γ, выбору модели для расчета силы взаимодействия для дальнейшего определения локального модуля Юнга.

We propose a technique that optimizing the method of contact force spectroscopy. With the help of a macro language integrated into the NOVA software of the Solver P47 scanning probe microscope, an algorithm was developed that allows analyzing force curves without leaving its main interface. The approbation of the method was done on samples of synthesized polymer, since one of the most important mechanical properties determining their range of applications is elasticity. In this paper, local values of the Young's modulus on the polymer surface are obtained by the method of contact force spectroscopy using the YUNG script developed using a macro language integrated into the control program of a scanning probe microscope. It is shown that the use of the YUNG script makes it possible to optimize the method of contact force spectroscopy by searching for the exponent γ, choosing a model for calculating the interaction force for further determination of the local Young modulus.