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With excellent mechanic properties and hydrogen embrittlement (HE) resistance, 12Cr2Mo1R(H) steel is suitable to make hot-wall hydrogenation reactors. However, longtime exposure to a harsh environment of high-pressure hydrogen at medium temperature in practical application would still induce severe hydrogen uptake and eventually damage the mechanical properties of the steel. The study aims to evaluate the HE resistance of the steel under different tensile strain rates after hydrogen charging and analyze the hydrogen effect from atomic level.

This research studied the HE properties of 12Cr2Mo1R(H) steel by slow strain rate tests. Meanwhile, the effect of hydrogen on the structures and the mechanical properties of the simplified models of the steel was also investigated by first-principle calculations.

Experimental results showed that after hydrogen pre-charging in this work, hydrogen had little effect on the microstructure of the steel. The elongations and reduction of cross-sectional area of the samples reduced a lot, by contrast, the yield and tensile strengths changed slightly. The 12Cr2Mo1R(H) steel was not very susceptible to HE with a maximum embrittlement index of about 20.00%. First principles calculation results showed that after H dissolution, lattice distortion occurred and interstitial H atoms would preferentially occupy the tetrahedral interstitial site in bcc-Fe crystal and increase the stability of the supercells. With the increase of H atoms added into the simplified model, the steel still possessed a good ductility and toughness at a low hydrogen concentration, while the material would become brittle as the concentration of hydrogen continued to increase.

These finds can provide valuable information for subsequent HE studies on this steel.

12Cr2Mo1R(H) steel is commonly used to make hot-wall hydrogenation reactors given its excellent mechanical properties and hydrogen embrittlement (HE) resistance. Longtime exposure to high-pressure hydrogen at medium temperature would still severely damage the mechanical properties of the Cr-Mo steel with surface HICs caused by hydrogen adsorption and hydrogen uptake. The mechanisms of HE remain controversial and have not been fully understood so far.

The HE of the steel was investigated by slow strain rate test at different strain rates with in situ hydrogen charging. The diffusion coefficient of hydrogen in the steel is measured by electrochemical technology of hydrogen permeation. HIC cracks of the fractured specimens were captured with field emission SEM equipped with an electron backscatter diffraction system.

Results showed that the hydrogen led to the plasticity of the samples reduced significantly, together with the distinct work hardening behavior induced by hydrogen charging during plastic flow stage. The fracture of in situ charged sample changes from quasi-cleavage to intergranular fracture with the decreasing of strain rates, which indicates that the steel become more susceptible to hydrogen. High densities of dislocations and deformation are found around the crack, where grains are highly sensitive to HIC. Grains with different Taylor factor are more susceptible to intergranular crack.

The results of the study would be helpful to a safer application of the steel.

This paper aims to study the mechanism of hydrogen embrittlement in 12Cr2Mo1R(H) steel, which will help to provide valuable information for the subsequent hydrogen embrittlement research of this kind of steel, so as to optimize the processing technology and take more appropriate measures to prevent hydrogen damage.

The hydrogen diffusion coefficient of 12Cr2Mo1R(H) steel was measured by the hydrogen permeation technique of double electrolytic cells. Moreover, the influence of hydrogen traps in the material and experimental temperature on hydrogen diffusion behavior was discussed. The first-principles calculations based on density functional theory were used to study the occupancy of H atoms in the bcc-Fe cell, the diffusion path and the interaction with vacancy defects.

The results revealed that the logarithm of the hydrogen diffusion coefficient of the material has a linear relationship with the reciprocal of temperature and the activation energy of hydrogen atom diffusion in 12Cr2Mo1R(H) steel is 23.47 kJ/mol. H atoms stably exist in the nearly octahedral interstices in the crystal cell with vacancies. In addition, the solution of Cr/Mo alloy atom does not change the lowest energy path of H atom, but increases the diffusion activation energy of hydrogen atom, thus hindering the diffusion of hydrogen atom. Cr/Mo and vacancy have a synergistic effect on inhibiting the diffusion of H atoms in α-Fe.

This article combines experiments with first-principles calculations to explore the diffusion behavior of hydrogen in 12Cr2Mo1R(H) steel from the macroscopic and microscopic perspectives, which will help to establish a calculation model with complex defects in the future.

This paper examines China's historiography on foreign education since 1900, with an emphasis on the period since 1949. The understanding of “foreign education” in China during this period shifted rapidly from the Western-centered approach that had been introduced from Japanese during the late Qing dynasty and the Republic of China to the Soviet-centered approach that followed the founding of New China to a restoration of Western-centered approaches after the “opening” of the late 1970s and 1980s. The paper asks: how has the study of foreign educational history changed over time in the People's Republic of China, how has the broader discipline of history of education changed, and how have successive generations of historians of education conceived of their intellectual and political roles?

Grounded in archival documents and the published works of influential historians of education, this study notes the ways in which political regime change affected the construction and application of academic knowledge.

This study identifies four stages in the Chinese historiography on foreign education: a formative stage (from 1900 until the late 1940s); a difficult post-revolutionary recovery, followed by growth and then suppression (from 1949 until the mid-1970s); a period of achievement combined with an academic crisis (from 1978 until the early 2000s); and finally, a recent transition marked by theoretical innovation and global integration (from the 2000s until the present).

This study finds that a narrow focus on “practical utility” or service to politics and policy has perturbed historians of foreign education in China and stunted their field's development. A look back at early periods in the historiography offers a warning about the potential dangers of extreme ideological/political utilitarianism. These dangers existed not only in the history of foreign education but also in the history of education research more broadly. A close examination of these dangers can help twenty-first-century historians of education in China balance the practical, political and professional dimensions of their research. To grasp the meaning of foreign education, historical research needs to be politically independent.

By applying the American Customer Satisfaction Index (ACSI) model to virtual art exhibitions, this research aims to reveal insights into the factors impacting visitor satisfaction and electronic word-of-mouth (e-WOM). Furthermore, the investigation of exhibition promotion seeks to understand how external factors contribute to the overall visitor experience in virtual art exhibitions.

With advancements in virtual communication technology and the transformative impact of the COVID-19 pandemic in recent years, there has been a notable surge in the popularity of virtual art exhibitions based on the Internet. This study uses the ACSI model to examine visitor satisfaction and e-WOM in virtual art exhibitions. Additionally, it explores the influence of exhibition promotion on the ACSI model.

Key findings revealed that 1) both promotion efforts and e-WOM exhibited significant relationships with the ACSI model, and 2) most of the relationships within the ACSI model were consistent with previous research outcomes.

This study extends the ACSI model’s application to virtual art exhibitions, enhancing its relevance. Additionally, it addresses the knowledge gap concerning the direct impact of promotion on audience expectations and its relationship with the ACSI model in virtual art exhibitions. Furthermore, the research explores the influence of customer satisfaction on electronic word-of-mouth in exhibitions, offering valuable insights for exhibition evaluation systems. The study serves as a guide, providing data and models for researchers investigating virtual art exhibitions.

The paper aims to know about energy condition’s impacts on inflation comprehensively.

This paper constructs China’s energy condition index (ECI) by bringing in three variables (China’s energy price, consumption and production) based on the financial condition index.

The result of empirical analysis shows that the index can predict China’s inflation well.

China’s ECI can predict China’s inflation well.

“Sleeping beauties” are very common in science, so this paper aims to uncover the reasons and formulation mechanism of information awakening on a more general level. Based on this, the paper will further propose useful strategies to awaken those “sleeping beauties” earlier.

Explanation‐building of case study is used to develop some models of information awakening and also to uncover different types of reasons for triggering academic information to be awakened.

Based on the three basic elements of information utilisation, namely, information value, access channel and user needs, the paper summarises several reasons for information awakening: the information value is re‐mined because of the relevance among various information; different uses of information are discovered; information availability and visibility are improved; information is placed into the appropriate place; and, with time passing by, demands for the information rise.

The presence of excessive “sleeping beauties” is not only a kind of idleness and waste to knowledge, but also may result in aggravation of information redundancy and increasing cost of storage. The revelation of its essence and reasons is not only helpful to establish better management mechanism to awaken “sleeping beauties” and thus to maximise their value, but also helpful to distinguish “sleeping beauties” from “pseudo‐sleeping beauties” as early as possible, so that all that worthless information can be cleared up without hesitation.

Most existing studies remain on the level of collecting instances and interpreting specific cases, but this paper investigates reasons from a more general level. What is more, current understandings are very one‐sided in that they treat information awakening and delayed recognition as the same, so this paper clarifies their differentiation and summarises the reasons comprehensively.

Interorganizational reciprocity plays a key role in relationships among software firms and open source communities. This study seeks to illuminate how a firm's open source strategy, characterized by its participation in the open source community, contributes to its financial performance.

Based on the norm of reciprocity and social capital theory, the study proposes a model comprising the behavioral antecedents and business results of a firm's symbiotic relationship with the open source community. Data were collected through a survey. Partial least squares-based structural equation modeling (PLS-SEM) was used to assess the results.

A firm's participative behaviors can have three dimensions: technology giving, technology taking and social participation. Technology taking directly impacts financial performance, whereas the effects of technology giving and social participation on financial performance are fully mediated by the firm's symbiotic relationship with the open source community.

Managers can understand how a specific behavior ultimately contributes to a symbiotic relationship or a firm's financial performance and how to flexibly align participation strategies with the business orientation.

The study adds to the open source literature by refining and enriching the conceptual domain of a firm's participative behaviors in open source communities. It also reveals how contrasting behavioral strategies impact a firm's financial performance.

This paper aims to explore the characteristics of knowledge diffusion of library and information science to reveal its development trend and influence on other disciplines.

Based on the ESI discipline classification, this paper measures the knowledge diffusion from the library and information science to other disciplines over the last 24 years using indicators in four dimensions: breadth, intensity, speed and theme of knowledge diffusion.

The results show that the knowledge diffusion breadth of library and information science is wide, spreading to 21 ESI disciplines; the knowledge spread mainly concentrates in four soft or applied disciplines, and yet partially inter-disciplinary, and the knowledge diffusion intensity to each ESI discipline is parabolic whose highest point is mostly in 2004–2005; the speed of spreading to the 21 ESI disciplines is faster and faster, and the articles at the highest speed of knowledge diffusion are basically published after 2005; the knowledge diffusion themes are becoming increasingly diverse, deepening and specialization over time.

This paper modifies the relevant indicators of knowledge diffusion and constructs a measurement framework of knowledge diffusion from four aspects: breadth, intensity, speed and theme. The research method can also be used to explore the characteristics of knowledge absorption of a discipline from other ones.