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The water exit problem, which is ubiquitous in ocean engineering, is a significant research topics in the interaction between navigators and water. The study of the water exit problem can help to improve the structural design of marine ships and underwater weapons, allowing for better strength and movement status. However, the water exit problem involves complex processes such as three-phase gas–liquid–solid coupling, cavitation, water separation, liquid surface deformation, and fragmentation, making it challenging to study. Following work carried out by many researchers on this issue, we summarize recent developments from three aspects: theoretical research, numerical simulation, and experimental results. In theoretical research, the improved von Karman model and linearized water exit model are introduced. Several classical experimental devices, data acquisition means, and cavitation approaches are introduced in the context of experimental development. Three numerical simulation methods, namely, the BEM (Boundary Element Method), VOF (Volume of Fluid), and FVM (Finite Volume Method) with LES (Large Eddy Simulation) are presented, and the respective limitations and shortcomings of these three aspects are analyzed. Finally, an outlook on future research improvements and developments of the water exit problem is provided. [ABSTRACT FROM AUTHOR]

Rock burst disasters severely restrict the safe and efficient mining of coal. The fundamental cause of their occurrence is the concentration of stress within the coal mass. Stress monitoring in coal seam drilling is widely used as an effective method for rock burst monitoring. However, how to scientifically and reasonably set the critical values of early warning indicators that match the conditions of each mine has always been a key issue restricting the accurate prediction of rock burst by the drilling stress method. This paper adopts a method combining theoretical analysis and field practice to conduct research on the critical values of drilling stress early warning indicators. Based on perturbation response instability theory, a mechanical model for the occurrence of impact ground pressure has been established. Based on the instability theory of disturbance response, a mechanical model for the occurrence of impact ground pressure has been established, leading to the derivation of the expression for the near-field critical stress of impact ground pressure events. The theoretical formula for the critical value of drilling stress early warning indicators was obtained based on the difference between the critical stress of rock burst occurrence and the actual stress in the roadway. This formula includes the mechanical parameters of the coal mass and its propensity for rock burst, roadway support stress, mining depth, stress concentration coefficient, and the initial installation pressure of the stress gauge. They can be determined by the geological and mining technical conditions of each mine. This theoretical formula breaks the uniformity of the critical values for stress warning indicators in various mine drill holes, allowing each mine to scientifically determine its critical value based on its own conditions. This theoretical method has been applied to a high-stress mine in Shanxi, China, and the critical values of drilling stress early warning indicators were obtained. When the monitored stress exceeded the critical value, dynamic phenomena of anchor rod and cable fractures occurred in the roadway roof. The distribution of microseismic events also shifted towards the warning area, and the microseismic monitoring indicators reached the warning values. This confirmed the engineering feasibility of the critical values for drilling stress early warning indicators determined by the theoretical method. [ABSTRACT FROM AUTHOR]

Background: The health as expanding consciousness (HEC) theory posits that health and disease are interconnected components of a comprehensive process aimed at expanding consciousness. Aim: The objective of this study is to introduce the concept, research status and applications of HEC and offer a comprehensive understanding of its various key components. Data sources: Databases including EMBASE, PubMed, ScienceDirect, ProQuest, Wiley, Web of Science, Sinomed, China National Knowledge Infrastructure, Wanfang, and CQVIP, covering the period from 1986 to 2023. Method: Employing Rodgers' evolutionary concept analysis approach, this study included and analysed 70 studies. Results: The characteristics of HEC comprise aspects such as movement, time, space, energy, rhythm, and paradigm of health. The antecedents of HEC encompass disease, chaos, binding, centring, and choice point. Consequences associated with HEC include self-transcendence, unbinding, decentring, expanded consciousness, real freedom, pattern recognition, absolute consciousness, and death. Conclusion: This study has identified substitute terms, related concepts, attributes, antecedents, consequences, and empirical references associated with HEC. The findings provide valuable information applicable across various domains of nursing, encompassing practice, education, research, and management. [ABSTRACT FROM AUTHOR]

Abstract Rock burst disasters severely restrict the safe and efficient mining of coal. The fundamental cause of their occurrence is the concentration of stress within the coal mass. Stress monitoring in coal seam drilling is widely used as an effective method for rock burst monitoring. However, how to scientifically and reasonably set the critical values of early warning indicators that match the conditions of each mine has always been a key issue restricting the accurate prediction of rock burst by the drilling stress method. This paper adopts a method combining theoretical analysis and field practice to conduct research on the critical values of drilling stress early warning indicators. Based on perturbation response instability theory, a mechanical model for the occurrence of impact ground pressure has been established. Based on the instability theory of disturbance response, a mechanical model for the occurrence of impact ground pressure has been established, leading to the derivation of the expression for the near-field critical stress of impact ground pressure events. The theoretical formula for the critical value of drilling stress early warning indicators was obtained based on the difference between the critical stress of rock burst occurrence and the actual stress in the roadway. This formula includes the mechanical parameters of the coal mass and its propensity for rock burst, roadway support stress, mining depth, stress concentration coefficient, and the initial installation pressure of the stress gauge. They can be determined by the geological and mining technical conditions of each mine. This theoretical formula breaks the uniformity of the critical values for stress warning indicators in various mine drill holes, allowing each mine to scientifically determine its critical value based on its own conditions. This theoretical method has been applied to a high-stress mine in Shanxi, China, and the critical values of drilling stress early warning indicators were obtained. When the monitored stress exceeded the critical value, dynamic phenomena of anchor rod and cable fractures occurred in the roadway roof. The distribution of microseismic events also shifted towards the warning area, and the microseismic monitoring indicators reached the warning values. This confirmed the engineering feasibility of the critical values for drilling stress early warning indicators determined by the theoretical method.

Abstract Background The health as expanding consciousness (HEC) theory posits that health and disease are interconnected components of a comprehensive process aimed at expanding consciousness. Aim The objective of this study is to introduce the concept, research status and applications of HEC and offer a comprehensive understanding of its various key components. Data sources Databases including EMBASE, PubMed, ScienceDirect, ProQuest, Wiley, Web of Science, Sinomed, China National Knowledge Infrastructure, Wanfang, and CQVIP, covering the period from 1986 to 2023. Method Employing Rodgers’ evolutionary concept analysis approach, this study included and analysed 70 studies. Results The characteristics of HEC comprise aspects such as movement, time, space, energy, rhythm, and paradigm of health. The antecedents of HEC encompass disease, chaos, binding, centring, and choice point. Consequences associated with HEC include self-transcendence, unbinding, decentring, expanded consciousness, real freedom, pattern recognition, absolute consciousness, and death. Conclusion This study has identified substitute terms, related concepts, attributes, antecedents, consequences, and empirical references associated with HEC. The findings provide valuable information applicable across various domains of nursing, encompassing practice, education, research, and management.

This paper aims to discern, clarify, criticise, and advocate some uses of phenomenology in sociological research. Phenomenology is increasingly evoked or implicitly employed in sociological endeavours. Little attention, however, is paid to what is entailed in taking a phenomenological approach, and whether it is employed to advance empirical or theoretical knowledge. I build an analytic typology of different empirical and theoretical uses of phenomenology, criticise a range of these uses, and argue that other uses bear significant potential for the advancement of theoretical and empirical knowledge. The paper's main contribution lies in comparing and contrasting the many invocations of phenomenology in contemporary social scientific research to discern their benefits and shortcomings. [ABSTRACT FROM AUTHOR]

High-rise buildings are inherently vulnerable to substantial wind-induced forces. The increasing complexity of building designs has posed challenges in calculating wind loads, while traditional methods involving physical models have proven to be intricate and time-consuming. In order to overcome these obstacles, this paper investigates a theoretical methodology aimed at streamlining the computation of wind loads. In the initial theoretical exploration, a simplified mathematical model based on Green's function is introduced to take into account the interaction between wind loads and building geometry, while the model is not user-friendly and difficult to solve for complex polygonal buildings. To overcome this challenge, the study incorporates numerical simulations to extend the ideas and refine the methodology. To simplify the problem from a three-dimensional to a two-dimensional context, a bold tangential field assumption is made, assuming the wind pressure distribution remains similar across horizontal sections at different heights. The Schwarz–Christoffel formulation is then employed to facilitate the transformation. By integrating Green's functions and conformal mapping to solve potential flow problems beyond the boundary layer, a comprehensive mathematical derivation is established. The above broadens the applicability of the mathematical theory and provides a new direction for estimations of high-speed wind load on buildings. [ABSTRACT FROM AUTHOR]

Karst caves should be avoided as far as possible during pile foundation construction, but sometimes it is unavoidable. Therefore, research on the bearing characteristics of pile foundations in karst areas is a problem that must be faced. The current status of research on the bearing characteristics of pile foundations in karst areas from three aspects: theoretical research, physical experiments, and numerical simulation was analyzed. The following conclusion was drawn. The existing bearing capacity calculation formulas have insufficient consideration of influencing factors, and subsequent theoretical research should consider the derivation of single pile ultimate bearing capacity calculation formulas under the synergistic influence of multiple factors. The variables in physical model tests are relatively single, and the influence of water on the bearing characteristics of pile foundations is often ignored during the testing process. Subsequent research should focus on the synergistic effect of groundwater and multiple factors. There are few in-situ experiments conducted, and the accuracy of the data obtained through detection needs to be improved. In the future, more in-situ experiments and in-site damage experiments should be carried out to obtain more comprehensive experimental data on the bearing characteristics of pile foundations. Most of the cave models are built with standard size in numerical simulation, which is inconsistent with the three-dimensional geometric size of the actual stratum cave. The establishment of a more realistic Geometric modeling of the cave is a key development direction in the future. [ABSTRACT FROM AUTHOR]

On the occasion of the death of Robert R. Holt (1917-2024), the Italian edition of the “personal introduction” to his book Freud Reappraised. A Fresh Look at Psychoanalytic Theory (New York: Guilford, 1989) is reprinted. In this introduction, Holt retraces the main aspects of his life as a scholar and theoretical researcher. Holt’s teachers and mentors included, among others, Gordon Allport, Henry A. Murray, and David Rapaport, and we can say that he has been an important witness of the history of psychology and psychoanalysis of the 20th century in North America. Holt was member of the editorial board of the journal Psicoterapia e Scienze Umane (“Psychotherapy and the Human Sciences”), in which he published various contributions, and came several times to hold seminars in Italy [ABSTRACT FROM AUTHOR]

The water exit problem, which is ubiquitous in ocean engineering, is a significant research topics in the interaction between navigators and water. The study of the water exit problem can help to improve the structural design of marine ships and underwater weapons, allowing for better strength and movement status. However, the water exit problem involves complex processes such as three-phase gas–liquid–solid coupling, cavitation, water separation, liquid surface deformation, and fragmentation, making it challenging to study. Following work carried out by many researchers on this issue, we summarize recent developments from three aspects: theoretical research, numerical simulation, and experimental results. In theoretical research, the improved von Karman model and linearized water exit model are introduced. Several classical experimental devices, data acquisition means, and cavitation approaches are introduced in the context of experimental development. Three numerical simulation methods, namely, the BEM (Boundary Element Method), VOF (Volume of Fluid), and FVM (Finite Volume Method) with LES (Large Eddy Simulation) are presented, and the respective limitations and shortcomings of these three aspects are analyzed. Finally, an outlook on future research improvements and developments of the water exit problem is provided.

Authenticity is considered a central feature in the context of teaching and learning mathematical modelling and is often demanded for both learning tasks and test items. Although large-scale studies hark back to this construct for years, it is largely unclear how a theoretical and empirically robust model for the description and practical operationalization of authenticity in modelling test items might look like. The article addresses this research desideratum and aims at deriving such a model based on existing theoretical concepts in mathematics education. The article provides a broad theoretical overview of the status quo of the construct and presents the "Model for Authenticity in Modelling Test Items" (MAMTI) as a result of those theoretical considerations. The model is based on the ideas of constructivist object authenticity and comprises a total of 8 aspects: real-world context, events, objects, question/assignment, data, figures, use of mathematics and purpose. The model enables further empirical studies to analyze and classify modelling test items or to vary them in terms of authenticity expression. [ABSTRACT FROM AUTHOR]

This article presents the latest progress in research on tire–pavement contact behavior. Firstly, the tire–pavement contact characteristics and their influencing factors are summarized. Then, the measurement methods and theoretical research on tire–pavement contact behavior are reviewed, and the advantages and shortcomings of different methods are compared and analyzed. Finally, analysis in the field of pavement engineering is summarized based on contact behavior. This article suggests a few key research directions: Tire–pavement contact behavior is influenced by multiple factors; therefore, multi-physical field-coupling analyses need to be carried out. Tire–pavement contact tests are mostly static and non-standardized, and it is a future trend to develop high-precision, low-cost, and standardized instruments that can measure dynamic contact. Theoretical research models rarely involve environmental factors; a contact model of the tire, pavement, and environment needs to be constructed that can truly describe the contact process. There is a relationship between contact characteristics and pavement performance; pavement performance evaluation indexes need to be established based on tire–pavement contact characteristics in the future. [ABSTRACT FROM AUTHOR]

The explorations of new three-dimensional (3D) microporous metal halides, especially the iodoargentate-based hybrids, and understanding of their structure-activity relationships are still quite essential but full of great challenges. Herein, with the aromatic 4,4′-dpa (4,4′-dpa = 4,4′-dipyridylamine) ligands as the structural directing agents, we solvothermal synthesized and structurally characterized a novel member of microporous iodoargentate family, namely [H2-4,4′-dpa]Ag6I8 (1). Compound 1 possesses a unique and complicated 3D [Ag6I8]n2n− anionic architecture that was built up from the unusual hexameric [Ag6I13] secondary building units (SBUs). Research on optical properties indicated that compound 1 exhibited semiconductor behavior, with an optical band gap of 2.50 eV. Under the alternate irradiation of light, prominent photoelectric switching abilities could be achieved by compound [H2-4,4′-dpa]Ag6I8, whose photocurrent densities (0.37 μA·cm−2 for visible light and 1.23 μA·cm−2 for full-spectrum) compared well with or exceeded those of some high-performance halide counterparts. Further theoretical calculations revealed that the relatively dispersed conduction bands (CBs) structures in compound 1 induced higher electron mobilities, which may be responsible for its good photoelectricity. Presented in this work also comprised the analyses of Hirshfeld surface, powder X-ray diffractometer (PXRD), thermogravimetric measurement, energy-dispersive X-ray spectrum (EDX) along with X-ray photoelectron spectroscopy (XPS). [ABSTRACT FROM AUTHOR]

A clear and systematic cognition of large deformation of tunnel surrounding rock is important for the further and specific research. Based on the existing research, large deformation of tunnel surrounding rock is defined as the deformation phenomenon, with obvious time effect and plastic deformation, exceeding the allowable range of specification and having seriously effects on the normal usability of tunnel engineering and even ultimately leading to the loss of the overall structural stability of tunnel. From the angle of deformation origin, the types of large deformation of tunnel surrounding rock are reclassified to expansion type, high ground stress soft rock type, loess type, high ground temperature type, and compound type. The deformation mechanism, constitutive model and supporting theory of large deformation of various surrounding rock types are summarized, and the control measures and construction methods are taken for different types of large deformation of surrounding rock. In this process, it was found that there are still some deficiencies, and possible future development trends are put forward: (1) The mechanism of large deformation of tunnel surrounding rock will be improved, and the law of large deformation and stress characteristics of tunnel surrounding rock are summarized through field detection, model test and finite element analysis and simulation, which can provide scientific basis for engineering practice and achieve accurate support of large deformation. (2) The classification control measures for large deformation of surrounding rock of different types of tunnels are unified. Due to the variety, complexity, and particularity of the project, it is difficult to summarize the general control measures for all types of large deformation of surrounding rock of various tunnels. However, based on a large number of large deformation cases, the formulation of control measures for specific large deformation type of different types of tunnels still has high engineering reference value. [ABSTRACT FROM AUTHOR]

The article "General Educational Science and the Problematisation of Pedagogical Knowledge - in the Age of AI" discusses the debate about the use of ChatGPT in higher education and emphasizes the relevance of General Educational Science. It is shown how this is realized as a "problem" in current forms of educational research. The article examines the impact of ChatGPT on university teaching and examination and discusses the opportunities, risks, and limitations of using AI models at universities. It emphasizes that the use of AI in higher education influences pedagogical processes of self-reflection and changes the shaping of pedagogy. The functions of General Educational Science and its relevance for problematizing pedagogy are examined, and the effects of algorithmic rationality on higher education are discussed. [Extracted from the article]

Copyright of Zeitschrift für Erziehungswissenschaft is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Traditional Chinese philosophy is the cornerstone of Chinese civilization, while the theory of art education is its cornerstone. In traditional Chinese philosophy, the core of art education is to improve students’ humanistic qualities and make them talented individuals who can be applied to the country and society. China’s traditional philosophy can provide useful guidance for modern art education, and also reflect the Chinese society’s core values. Chinese traditional philosophy has guiding significance and concrete guiding function to art education theory. This paper made a comprehensive analysis of the influence of China’s traditional philosophy on art education theory. The goal of this study is to explore how China’s traditional philosophy guides and influences the theory of art education and its adaptability to China society. However, the theory of art education from the perspective of traditional Chinese philosophy has both historical factors and the requirements of modern social development, and the two are, to some extent, separate. Traditional Chinese philosophy and culture have a great impact on contemporary art education theory. Contemporary art education in China should organically combine tradition and modernity, and attach importance to using traditional philosophical ideas to inspire contemporary art education to achieve comprehensive development of contemporary art education. In this context, this article utilized traditional Chinese philosophy to organically link its connotation with the characteristics of art education, attempting to guide the development of art education theory from the perspective of traditional Chinese philosophy.

High-rise buildings are inherently vulnerable to substantial wind-induced forces. The increasing complexity of building designs has posed challenges in calculating wind loads, while traditional methods involving physical models have proven to be intricate and time-consuming. In order to overcome these obstacles, this paper investigates a theoretical methodology aimed at streamlining the computation of wind loads. In the initial theoretical exploration, a simplified mathematical model based on Green’s function is introduced to take into account the interaction between wind loads and building geometry, while the model is not user-friendly and difficult to solve for complex polygonal buildings. To overcome this challenge, the study incorporates numerical simulations to extend the ideas and refine the methodology. To simplify the problem from a three-dimensional to a two-dimensional context, a bold tangential field assumption is made, assuming the wind pressure distribution remains similar across horizontal sections at different heights. The Schwarz–Christoffel formulation is then employed to facilitate the transformation. By integrating Green’s functions and conformal mapping to solve potential flow problems beyond the boundary layer, a comprehensive mathematical derivation is established. The above broadens the applicability of the mathematical theory and provides a new direction for estimations of high-speed wind load on buildings.

Authenticity is considered a central feature in the context of teaching and learning mathematical modelling and is often demanded for both learning tasks and test items. Although large-scale studies hark back to this construct for years, it is largely unclear how a theoretical and empirically robust model for the description and practical operationalization of authenticity in modelling test items might look like. The article addresses this research desideratum and aims at deriving such a model based on existing theoretical concepts in mathematics education. The article provides a broad theoretical overview of the status quo of the construct and presents the “Model for Authenticity in Modelling Test Items” (MAMTI) as a result of those theoretical considerations. The model is based on the ideas of constructivist object authenticity and comprises a total of 8 aspects: real-world context, events, objects, question/assignment, data, figures, use of mathematics and purpose. The model enables further empirical studies to analyze and classify modelling test items or to vary them in terms of authenticity expression.

Smooth surface blasting control technology is aimed at blasting the rock body until it is left with a smooth surface and to protect it from damage; the current air spaced axial uncoupled charge and air spaced radial uncoupled continuous charge are effective charging structures for smooth surface blasting. Reserved air spacing can effectively reduce the blast wave and the peak pressure of the explosive gas, improving the quasi-static pressure of the explosive gas under the action of rock surface blasting with fracture seam quality. In order to ensure the effect of surface blasting, small-diameter light surface holes are more often used; with the development of drilling machinery, the use of large-diameter light blast holes with an oversized uncoupled coefficient of loading structure effectively improves the efficiency of the construction and at the same time achieves better blasting results. However, according to the bursting assumption of obtaining the theory of light surface blasting in the application of large uncoupling coefficient loading, light surface blasting has certain limitations. In this regard, the bursting theory explores the air spacing uncoupling charge in line with the multi-faceted exponential expansion of the critical uncoupling coefficient and is in accordance with the following: the requirements of light surface blasting and the field loading structure; the derivation of the quasi-static pressure on the wall of the gunhole under the action of large uncoupling, uncoupling coefficient, and the parameters of the spacing between the gunholes; the establishment of the axial uncoupling coefficient and the radial uncoupling coefficient-equivalent relationship between the uncoupling coefficient and the theoretical relationship between the selection of the spacing between the holes; the uncoupling coefficient and the selection of the theoretical relationship between the spacing between the holes. This study reveals the mechanism by which different parameters of surface blasting can achieve good results in engineering practices. A slope in Guizhou is an example of sample calculations and the application of two different charging structures applied to field loading, which have achieved good surface blasting results. [ABSTRACT FROM AUTHOR]

In order to study the transient temperature effect during the construction of a cross-sea bridge off the coast, based on the Hong Kong-Zhuhai-Macao Bridge-Pipe Bridge Crossing Cliff 13-1 Gas Field, a refined analysis was conducted and the prediction of transient temperature gradient and structural response was carried out under the conditions of strong solar radiation and atmospheric convection using the method of combining theoretical research and numerical simulation. Firstly, the partial differential equation of uniform heat flux density on the outer surface of the main girder under the action of solar radiation and atmospheric convection was established. The equation was realized by calculating the solar radiation intensity and the comprehensive heat transfer coefficient, as well as fitting the atmospheric temperature on the outer surface of the main girder, and the equivalent comprehensive temperature at any time on the main girder was obtained. Secondly, a numerical analysis model of the heat conduction of the main girder section was established, and the equivalent comprehensive temperature was input into the numerical model as the temperature field boundary to solve the transient temperature gradient of the section, and the result was verified in comparison with the measured data. Finally, the transient temperature gradient was applied to the girder, and the temperature effect of the main girder during the closing process was also calculated. Construction control measures were also discussed. The research results show that the predicted value of the transient temperature gradient is consistent with the measured value (the maximum deviation is less than 2 °C), and the predicted value is slightly larger than the measured value, which makes the structure safer. During the closing process, the temperature gradient of the main girder has obvious non-linear characteristics: the temperature gradient is relatively high within 0.4 m of the top surface of the roof while tending to zero outside 0.4 m. The best closing time for the main girder is from 21:00 in the evening of the closing day to 6:00 a.m. the next day. For the small angles at both ends of the closure segment during the best closing time, temporary adjustment jacks and temporary counterweights can be adopted to eliminate the small angles at both ends of the closure segment in order to facilitate the welding construction and meet the smoothness requirements of bridge alignment. [ABSTRACT FROM AUTHOR]

Fine-tuning of alloy composition is crucial for improving the temperature capacity of Ni-based superalloys, which is required for deeper understanding of the strengthening mechanisms of complex alloying. However, the typical strengthening elements Re and Mo still lack clear physical explanations on their synergistic effects on diffusion behaviors. They directly control the dislocation climb and further influence the steady creep rate under high temperatures. In this work, we perform a theoretical investigation on the vacancy-mediated diffusion behaviors regulated by Re and Mo conjunctively in the γ-Ni phase. Combined with the high-accuracy first-principles calculations, a kinetic Monte Carlo model is applied to Ni-Re-Mo ternary systems to evaluate their diffusion kinetics for the first time. The results verify that the 1Re1Mo additions exhibit comparable hindering effects on vacancy formation. The most increased effects on Ni self-diffusion barrier have also been found for 1Mo1Re substitutions compared with 2Re and 2Mo cases. Besides, Mo could elevate the diffusion barriers of Re to some extent and Re would dramatically improve the diffusion barriers of Mo. Especially, the quantified predictions of vacancy diffusion constants of Ni-Rex-Moy (x + y = 5 at.%) systems vary slightly within ∼5% compared with Ni-Re5 system. From the viewpoints of diffusion kinetics, we provide the theoretical interpretations for the synergistic effects of Re–Mo co-alloying and verify the feasibility of partly substituting Mo for Re as an alloy design strategy.

An interesting chiral molecule with a double half-twisted π-electron system has been investigated with theoretical calculations. To investigate the geometry and electronic structure, the size of macrocyclic cavity, electrostatic potential (ESP) and density-of-states (DOS) were calculated. The multi-center bond order (MCBO) and AV1245 index were calculated to compare the aromaticity of phenylene groups. To investigate the spectroscopic properties, Raman, Raman Optical Activity (ROA), UV–Vis spectrum, fluorescence, CPL (circularly polarized luminescence) and ECD (electronic circular dichroism) spectra have been calculated and analyzed. The oscillator strengths, rotatory strengths and dissymmetry factor (glum) have been discussed. [ABSTRACT FROM AUTHOR]

Copyright of Zeitschrift für Pädagogik is the property of Julius Beltz GmbH & Co. KG Beltz Juventa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Translation strategies have been the subject of extensive research. However, each author or theorist's definition expresses his or her own point of view, and their opinions diverge from one another. The majority of theories concur that translators employ techniques when literal translation fails to solve a problem. Consequently, several translation procedures have been examined and explained by diverse researchers from their individual points of view. This study describes and contrasts some of the most well-known hypotheses in this field. This study's objectives were to provide the many theories in the field of translation strategies and to provide a comprehensive evaluation of the literature to aid in the study of translation strategies in future research. This article offers the clearest taxonomy of translation strategies that professional translators use when they encounter a translation problem while performing a translation task. [ABSTRACT FROM AUTHOR]

With growing awareness of unsustainable practices, communities are forcing businesses and governments to take serious steps towards sustainability. Microplastics enter the food chain and eventually reach humans. The threat of global warming and recurrent climate disasters necessitate immediate action. However, all governments and corporations rely on an 'increase in demand' as a growth metric, which prevents them from doing anything meaningful to ensure our planet's long-term viability. Against the above paradox, this article explores a compromise between sustainability, consumption, and economic growth. It is a theoretical framework for proposing a solution in which businesses can expand in tandem with our planet's long-term future or a glance through the areas where the Keynesian economy can coexist with environmentalists' concerns. The proposed framework claims significance in terms of practicality than the perfection of a solution. [ABSTRACT FROM AUTHOR]

Introduction. Nowadays the part of the diesel engines for KamAZ-740 cars are operated with fuel equipment, in which the injectors have hydro mechanical control. Their main disadvantage is the low fuel pressure in front of the injector openings (less than 60 MPa) and the lack of fuel supply control.The use of injectors with electro hydraulic control (EHC) increases the pressure in the injector cavity up to 250 MPa and control the fuel injection process. The disadvantage of the injectors with EHC is a structural complexity of a control valve, the difficulty of its regulation and coding. The object of the study is the injectors of KamAZ-740 diesel engine with electro hydraulic control of the atomizer needle stroke.The purpose of this work is to carry out theoretical research and improve the methods of maintenance of injectors with electro hydraulic control (control valve regulation and coding), which will increase their reliability, durability and ensure a reduction in diesel fuel consumption.Research methods. The study of the nozzle control valve is theoretical and calculated. The paper proposes a calculation method and performs theoretical studies for the influence of pressure (50 – 250 MPa) on the value of the effective flow section and the diameter of the nozzle holes of the sprayer.For the injectors with EHC, the control valve regulation procedure has been clarified, which consists in the fact that at the beginning of regulation, the main force acting on the ball from the side of the maximum pressure in the control chamber (for example, 200 MPa) equal to 76 N is calculated (see Figure 4). Then the required spring force of 100 N is determined (20-40% more, see Figure 5). Next, the strength of the electromagnet is estimated at 140 N (20 – 40% more of the spring force, see Figure 6).The results of theoretical research. The results of computational (theoretical) studies for the effective flow section of the sprayer and the diameter of the nozzle holes, depending on the pressure P in front of the nozzle holes, are presented.The paper defines. 1. The forces acting on the ball (57 – 105 N) depending on the pressure in the control chamber (150 – 275 MPa). 2. Spring forces (40 – 140 N) with a stiffness of 40 N /mm, depending on its compression up to 3.5 mm. 3. The forces of the electromagnet (140 – 20 N) depending on the gap between the anchor and the core (0.2 – 0.5 mm).The method of restoring the required (rated) cyclic fuel supply when it changes as a result of replacing the control valve or adjusting is considered. The calculated values of fuel supply per cycle (mm3/cycle) from the activation time are given.Conclusion. The results of the study are intended for organizations and enterprises engaged in diagnostics, restoration, adjustment and coding of injectors with electro hydraulic control for the needle stroke of sprayers. The results of computational studies can be used to refine the methodology of maintenance of fuel systems with electronic control (Common Rail).

China is rich in lithium resource, among which lithium ore in the Salt Lake has huge reserves, but the development and utilization technology has yet to be developed, and the main target of development is hard-rock lithium ore at present. Hard-rock lithium ore is mainly pegmatitic and concentrated in Xinjiang and Sichuan. The Mesozoic is the most important metallogenic period for pegmatite-type lithium deposits in China. A relatively stable tectonic environment after an orogeny is favored by the formation of pegmatite-type lithium deposits. After a decade of exploration practice and theoretical research, the types of lithium resource in China have shown a great variety. The brine-type lithium resource has expanded from surface brine to both shallow brine and deep brine, and the hard-rock lithium resources from single granitic pegmatite-type to altered granite-type, cryptoexplosion breccia tube-type and sedimentary-type. The metallogenic age has extended from the Meso-Cenozoic to the Paleozoic and other epochs. The metallogenic zones has increased from 12 to 16, and a number of new mineralized areas have been discovered in the Jiajika and Ke’eryin areas in western Sichuan and the Dahongliutan and Shaligou areas in Xinjiang . A new resource pattern of lithium is being formed. Moreover, Prospecting methods and exploration techniques have also developed from single surface prospecting and mapping to an integration of new techniques and methods, e.g., remote sensing to determine the prospective area, geological surveying to determine the type, geochemical prospecting to determine the mineral, geophysical prospecting to determine the location of drilling, drilling to determine the reserves, as well as biological prospecting, deep penetration of the deep exploration. In view of the rigid demand for lithium resources due to the rapid development of strategic emerging industries, it is suggested to strengthen a) the investigation, research, development and utilization of new types of lithium resources with lepidolite as the main industrial mineral and sedimentary-type lithium resources with Li-bearing clay as the main lithium resources; b) the research and prospecting of the Paleozoic and even Precambrian lithium deposits; c) the exploration of new lithium mineralization belts such as Altyn Tagh, Himalaya, Gangdise and western slope of Great Hinggan Mountains; d) the research on new mechanisms of dynamic management of lithium resources under market economy; e) the advanced research and resource reserve on lithium isotope as the raw material of controllable nuclear fusion, for leading the development of high-end mining industry.

With the in situ-formed [MDMAP]+ (MDMAP+ = 1-methyl-4-dimethylaminopyridine) cations as structure-directing agents, a new chain-typed iodoplumbate hybrid, i.e., [MDMAP]PbI3 (1) has been solvothermally obtained and structurally characterized. Compound 1 belongs to the Pbca (No. 61) space group and has an infinite one-dimensional (1 D) [Pb2I6]n2n− anionic chain. Interestingly, it exhibits the semiconductor behavior with the band gap of 2.82 eV, which endows it with rapid and conspicuous photocurrent response property. Presented in this work also includes its thermal stability, X-ray photoelectron spectroscopy characterization and theoretical studies. [ABSTRACT FROM AUTHOR]

The existing seal is not designed with a special sand retaining structure, and it is difficult to discharge the mud particles after entering, resulting in serious wear of the seal and premature failure. Therefore, a special-shaped sealing structure for sand blocking of roller cone bits is proposed to solve the problem of sealing wear. Starting from the structural principle, the structural parameters of the special-shaped seal of the sand-retaining flap are designed based on the O-ring, and the sealing principle is analyzed, the formula of grease leakage is derived, and the simulation and optimization analysis are completed with the aid of APDL. This proved the feasibility of the design. The influence law of structural parameters on contact pressure and leakage is obtained, and the formula of leakage is verified; The influence of structural parameters on the contact gap of the sand flap is obtained. Under the condition of optimal combination of structural parameters, the grease leakage is 43 mg/h, a decrease of 85%. Theoretically, it takes 580 h to exhaust the grease, and the contact gap of the sand flap is 0.00019479 mm, a decrease of 95%, which can greatly reduce the wear of the main seal. This study opens up a new idea for seal design. [ABSTRACT FROM AUTHOR]

When theorizing, it is sometimes colloquially said "I reckon..." This essay attempts to reckon with theorizing by proposing a heuristic for systematically gauging rigorous and/or meaningful theoretical research with the analysis of eight factors: novelty, challenge, relevance, power, fecundity, usefulness, deliberateness, and clarity. These factors offer a manual for theorists writing theoretical research, and a loose set of considerations to begin discussions of what it is that makes invigorating theory. [ABSTRACT FROM AUTHOR]

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The explorations of new three-dimensional (3D) microporous metal halides, especially the iodoargentate-based hybrids, and understanding of their structure-activity relationships are still quite essential but full of great challenges. Herein, with the aromatic 4,4′-dpa (4,4′-dpa = 4,4′-dipyridylamine) ligands as the structural directing agents, we solvothermal synthesized and structurally characterized a novel member of microporous iodoargentate family, namely [H2-4,4′-dpa]Ag6I8 (1). Compound 1 possesses a unique and complicated 3D [Ag6I8]n2n− anionic architecture that was built up from the unusual hexameric [Ag6I13] secondary building units (SBUs). Research on optical properties indicated that compound 1 exhibited semiconductor behavior, with an optical band gap of 2.50 eV. Under the alternate irradiation of light, prominent photoelectric switching abilities could be achieved by compound [H2-4,4′-dpa]Ag6I8, whose photocurrent densities (0.37 μA·cm−2 for visible light and 1.23 μA·cm−2 for full-spectrum) compared well with or exceeded those of some high-performance halide counterparts. Further theoretical calculations revealed that the relatively dispersed conduction bands (CBs) structures in compound 1 induced higher electron mobilities, which may be responsible for its good photoelectricity. Presented in this work also comprised the analyses of Hirshfeld surface, powder X-ray diffractometer (PXRD), thermogravimetric measurement, energy-dispersive X-ray spectrum (EDX) along with X-ray photoelectron spectroscopy (XPS).

The discussion reflects the points of view of doctors of sciences from the Russian State Library, the Russian National Library, the Saint-Peterburg State Institute of Culture and the State Public Scientific and Technical Library of the Siberian Branch of the Russian Academy of Sciences (SPSTL SB RAS), voiced on March 16, 2022 at the round table “Science in Libraries”. The round table was held within the framework of the international conference “Libway” held by the SPSTL SB RAS. The participants of the discussion answered the following questions: general assessment of the state of domestic library science, book science, bibliography; key areas of library science, book science and bibliography in the second decade of the 21st Century; problems of scientific personnel training; the place of library science and the prospects for its development within the new Nomenclature of scientific specialties. The discussion made it possible to single out the following problems: the importance of solving practice-oriented problems of library science and bibliography, and only then their theoretical analysis and generalization; work in the library field of specialists from other industries with a poor understanding of librarianship and bibliography issues; lack of educational and methodological materials for graduate students and their supervisors; a very small number of state-funded places in graduate school and the lack of material incentives to attract specialists to scientific research. In a general assessment of the state of the disciplines of the documentary and communication cycle, opinions differed – from an optimistic view of the future of these disciplines to a pessimistic one due to the presence of numerous internal problems. The necessity of collaboration is stressed. All participants expressed their deepest satisfaction with the inclusion of library, bibliography and book sciences in the new Nomenclature of scientific specialties and the emergence of a new specialty passport.

A mechanical model of a circular section of a tunnel roadway considering damage is established to improve the impact protection performance of the “roadway rock-support” system and provide a theoretical basis for designing coal mine impact ground pressure roadway support. The formula of the critical rock burst load of a circular roadway is derived according to the instability theory of rock burst disturbance response. The influence of mechanical properties of surrounding rock and roadway support strength on the critical rock burst load of a roadway rock-support system is studied using the control variable method. The research shows that 1) under the support condition of a roadway, with the increase of uniaxial compressive strength, softening modulus, and internal friction angle of surrounding rock, the critical rock burst load of a roadway has an increasing trend; the critical rock burst load of roadway decreases with the increase of the elastic modulus of the surrounding rock. 2) Under the condition of no support, with the increase of uniaxial compressive strength, elastic modulus, and internal friction angle of surrounding rock, the critical rock burst load of roadway tends to increase. With the decrease of the surrounding rock’s softening modulus, the critical rock burst load of the roadway decreases. When the aforementioned four kinds of surrounding rock influence factors are the same, the critical load of rock burst under the supporting condition is much larger than that under the non-supporting condition. 3) A new impact tendency index K is defined as the ratio of the softening modulus and the elastic modulus. 4) The critical load of rock burst increases approximately linearly with the increase of support stress. The critical load of a rock burst is about 400 times as large as the supporting stress. Increasing roadway support strength can greatly improve the stability of the supporting and roadway surrounding rock system, and the stability of the supporting and roadway surrounding rock system can be improved by reasonably changing the mechanical properties of the surrounding rock.

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A series of cyclometalated platinum (II) complexes with aromatic ligands, such as pyridyl, pyrimidinyl, and pyrazolate, were investigated with theoretical calculations. To investigate the relationship between ligands with molecular orbital, molecular rigidity, electroluminescent properties, and spectroscopic properties, the electrostatic potential (ESP), density-of-states (DOS), and root mean squared displacement (RMSD) were calculated. On the basis of calculated absorption and phosphorescence data, the analysis of 'hole' and 'electron' have also been performed. From the RMSD and spin–orbit coupling (SOC) matrix elements calculations, complex 3 shows significant structural distortions on S1 state and it may be applied in thermal activation delayed fluorescence (TADF) materials. The electroluminescent properties calculations show that complex 1 is suitable for hole transport material and complex 4 can be applied to electron transport material. [ABSTRACT FROM AUTHOR]

• Novel optimization strategies of vapor chamber using emerging thermal management technologies. • Complex mechanisms with heat and flow regimes and multi-scales were considered. • The technical limitation existing as well as the challenges of future research were proposed. • Micro-nanomanufacturing technology enhances the heat transfer performance of vapor chamber. With the rapid development of the economy and society, the contradiction between energy supply and the deterioration of the ecological environment has become increasingly prominent. Efficient thermal management, capable of reducing water and energy consumption while maintaining environmental sustainability, has emerged as a pivotal factor in addressing the prevailing energy crisis, garnering significant attention. Due to latent heat induced super thermal conductive capability, robustness and localized hotspot mitigation ability, vapor chambers (VCs) have emerged as one of the most efficient thermal management solutions for high heat flux cooling. Numerous researchers have diligently worked on enhancing VC heat transfer performances from the aspects of wick design, evaporation/condensation, and liquid-vapor transport. Based on the specific functions triggered by structural changes, this review comprehensively summarizes the latest research progress of novel VC designs, encompassing aspects such as heterogeneous/hybrid wettability design, biomimetic wick design, vapor-liquid space design, nanoengineered and new materials, extreme scale design, and integrated design. Subsequently, the latest advancements in the optimization of wick-level thin film evaporation/boiling and the enhanced capillary performance are discussed, while offering comparisons of their respective advantages and disadvantages. Furthermore, the diverse applications of VCs in electronic cooling, proton exchange membrane fuel cells, battery thermal management systems, solar cells, waste heat recovery, and space exploration are introduced. Finally, this review is concluded by providing the existing challenges and suggested directions for future research directions. [ABSTRACT FROM AUTHOR]

Smooth surface blasting control technology is aimed at blasting the rock body until it is left with a smooth surface and to protect it from damage; the current air spaced axial uncoupled charge and air spaced radial uncoupled continuous charge are effective charging structures for smooth surface blasting. Reserved air spacing can effectively reduce the blast wave and the peak pressure of the explosive gas, improving the quasi-static pressure of the explosive gas under the action of rock surface blasting with fracture seam quality. In order to ensure the effect of surface blasting, small-diameter light surface holes are more often used; with the development of drilling machinery, the use of large-diameter light blast holes with an oversized uncoupled coefficient of loading structure effectively improves the efficiency of the construction and at the same time achieves better blasting results. However, according to the bursting assumption of obtaining the theory of light surface blasting in the application of large uncoupling coefficient loading, light surface blasting has certain limitations. In this regard, the bursting theory explores the air spacing uncoupling charge in line with the multi-faceted exponential expansion of the critical uncoupling coefficient and is in accordance with the following: the requirements of light surface blasting and the field loading structure; the derivation of the quasi-static pressure on the wall of the gunhole under the action of large uncoupling, uncoupling coefficient, and the parameters of the spacing between the gunholes; the establishment of the axial uncoupling coefficient and the radial uncoupling coefficient-equivalent relationship between the uncoupling coefficient and the theoretical relationship between the selection of the spacing between the holes; the uncoupling coefficient and the selection of the theoretical relationship between the spacing between the holes. This study reveals the mechanism by which different parameters of surface blasting can achieve good results in engineering practices. A slope in Guizhou is an example of sample calculations and the application of two different charging structures applied to field loading, which have achieved good surface blasting results.

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Copyright of Bearing is the property of Bearing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Physical Education / Tiyu Xuekan is the property of Journal of Physical Education Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The stronger stability of a half-through truss bridge can improve the bridge performance for resisting extreme loads, such as earthquakes and shock. To improve the bridge stability, it is necessary to improve the torsional stiffness of the half-through truss bridge. To study the torsional characteristics of the main girder of the half-through truss bridge, the half-through truss is equivalent to an open slot thin-walled member, and the calculation formula of the free torsional moment of inertia of the main girder is deduced. Because the main truss can resist warping deformation through bending, it has a great contribution to the torsional stiffness. Based on the vertical bending action of the main truss, the calculation formula of the correction of the torsional moment of inertia of the main girder is deduced. Taking a half-through truss pedestrian bridge as an example, the torsional moment of inertia of the bridge under different width-span ratios is calculated by theoretical and finite element analysis. The results show that when calculating the torsional moment of inertia of the main girder of the half-through truss bridge, the free torsional moment of inertia calculated by the equivalent open slot section is very different from the actual torsional stiffness, and the bending correction value must be considered. The theoretical solution after taking into account the corrected value is well-fitted with the finite element results. The theoretical formula can be used to explain the torsional mechanism of this kind of bridge. According to the mechanism research, the method of installing X-shaped longitudinal supports between the upper transverse girders to improve the torsional stiffness is finally formulated. Installing the X-shaped longitudinal supports not only can keep the size of the half-through truss bridge unchanged but can also have a considerable enhancement effect, which will significantly improve the torsional stiffness and stability of existing bridges. [ABSTRACT FROM AUTHOR]

The increase in interest in science and scientific research, as a result of societal ambition in development and progress, has made different societies adopt different scientific methods, in preparing theoretical and applied research, but there are some studies that did not follow the steps of scientific research in formulating the form and content. Experts and professors specializing in providing some observations and directions to support researchers in the development of scientific research, from this point of view was the research problem that stresses the importance of the policy of development and intellectual creativity, in the scientific system, in order to contribute to providing positive solutions in the development of scientific research, and from this point of view can be identified The research problem in the following question: How can the scientific system be an important entry point in the development of theoretical and applied research in the field of design? Where the research assumes that the scientific system is the primary approach in developing theoretical and applied research in the field of design, and the research aims to activate the development policy in the formulation of theoretical and applied research while directing attention to theorizing applied research in the manner of theoretical research steps and dealing with the importance of research revealing the difference between formulating theoretical research And applied design in the field of design and contribution to the process of effective development in preparing scientific production in the scientific system, and the research methodology deals with dealing with the descriptive and analytical approach in several axes linked in a theoretical framework, first: strategies for preparing theoretical and applied research, and secondly: the components of formulating the topic of theoretical and applied research, Third: the formulation of goals and importance in scientific research, and fourth: the characteristics of interest in preparing theoretical and applied research, and fifth: the results and recommendations, the most important of which is that taking into account the scientific objectivity in preparing the research away from subjectivity, and that the steps of preparing theoretical research are the same as the steps of preparing research and applied.

The use of transcritical R744 systems has become increasingly popular in recent years in a variety of different applications. For applications that span a wide temperature range between the heat source and heat sink, the use of two-stage compressor results in numerous advantages in terms of efficiency and compressor discharge temperature. This paper presents experimental data for a transcritical R744 compressor system operating at high heat rejection temperatures. A comprehensive system model was developed and validated with the experimental results. Based on this, the simulation tool was used to further optimize the system design specifically to accommodate the two-stage compression process. The optimum heat transfer area distribution has been determined to simultaneously ensure efficient intercooling at intermediate pressure and gas cooling at the high-pressure level. Simultaneously, the system was also optimized with respect to optimal intermediate pressure and the results show that for this particular system, the optimum intercooler pressure deviated substantially from the standard design approach that uses the geometric mean between suction and discharge pressures