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Low-alloy structural steels (LASS) face severe microbiologically influenced corrosion (MIC) in their service environments. To mitigate this issue, Cu is often used as an alloying element owing to its intrinsic antimicrobial activity. However, the antibacterial performance and biofilm resistance of Cu-containing LASS (Cu-LASS) are still unclear. This study aims to analyze the effect of Cu addition to 420 MP LASS on its MIC by the Pseudomonas aeruginosa biofilm.

Scanning electron microscope, confocal laser scanning microscope and X-ray photoelectron spectroscopy were used to analyze the surface morphology and composition of corrosion products. The antibacterial activities of Cu-LASS were analyzed by the spread-plate method. In addition, electrochemical analysis was conducted to characterize the corrosion behavior of the produced alloy.

Bacterial analysis and morphological observation confirmed a reduced sessile cell count and inactivation of the P. aeruginosa biofilm on the surface of Cu-LASS coupons. Electrochemical measurements showed that Cu-LASS exhibited large polarization and charge-transfer resistances, which indicated excellent MIC resistance. This significantly enhanced resistance to MIC could be explained by the synergistic effect of released Cu²⁺ from the Cu-LASS surface and immediate contact to Cu-rich phase in the surface and the release of Cu²⁺ ions from the Cu-LASS surface.

The effect of Cu addition on the MIC resistance and antibacterial performance of LASS is seldom reported. It is necessary to investigate the corrosion resistance of Cu-LASS and clarify its antibacterial mechanism. This paper fulfills this need.

This paper aims to revel the leakage characteristics of the bent-axis piston pump considering elastohydrodynamic deformation via a dynamic leakage model.

A dynamic leakage model of bent-axis piston pump based on elastohydrodynamic lubrication theory is proposed, which is used to present the leakage characteristics of bent-axis piston pump. The model is composed of three parts. First, the dynamic gap in the piston ring-cylinder bore interface (PRCB) is described via the elastohydrodynamic lubrication equations. Then, the PRCB leakage is presented based on the dynamic gap. Finally, combined with leakage equation of the valve plate-cylinder block interface (VPCB), the total leakage model is proposed. Through the numerical simulation and experiment, the leakage characteristics of bent-axis piston pump considering elasto-hydrodynamic deformation are studied.

The PRCB leakage is negatively correlated with VPCB leakage under the range of 800–1400 r/min and 1–25 MPa. When the discharge pressure is less than the critical pressure, the PRCB leakage is the main factor affecting the total leakage in bent-axis piston pump. On the contrary, the VPCB leakage is the main factor. The critical pressure increases with increasing speed

The effect of operating parameters has a significant effect on the elastic deformation of piston ring without considering wear of friction pairs in bent-axis piston pump. There is a critical phenomenon in the leakage, which is related to the operating parameters, and provides a novel idea for extracting wear information from leakage and evaluating the status of bent-piston pump.

With the application and development of intelligent clothing and wearable technology, the term “micro-interaction” has gradually entered people’s lives. The paper aims to discuss this issue.

The paper takes the concept of “micro-interaction” as the design principle, starting from the consumer demand, combing the realization mode of the intelligent safety clothing in recent years, and finds out the existing problems in the design of the intelligent safety clothing.

Under the concept of micro-interaction, a new theoretical model has been proposed to study intelligent safety clothing. Finally, the paper also emphasizes the importance of the industrialization of the proposed model.

The paper proposes a new research and development mode for intelligent clothing in safety protection area which is a pioneering study and can be valuable for safety clothing manufacturers to produce more functional and attractive products.

The service environment of urban polyethylene (PE) pipes has a crucial influence on their long-term safety and performance. Based on the application and structural performance analysis of PE pipe failure cases, this study aims to investigate the impact of organic substances in the soil on the aging behavior of PE pipes by designing organic solutions with different concentrations, which are based on the composition of organic substances in the soil environment, and periodic immersion tests.

Soil samples in the vicinity of the failed pipes were analyzed by gas chromatography-mass spectrometry, sensitive organic substances were screened and soaking solutions of different concentrations were designed. After the soaking test, the PE pipe samples were analyzed using differential scanning calorimetry, Fourier-transform infrared spectroscopy and other testing methods.

The performance difference between the outer surface and the middle of the cross section of PE pipes highlights the influence of the soil service environment on their aging. Different organic solutions can have varying impacts on the aging behavior of PE pipes when immersed. For instance, when exposed to amine organic solutions, PE pipes may have an increased weight and decreased material yield strength, although there is no reduction in their thermal or oxygen stability. On the contrary, when subjected to ether organic solutions, the surface of PE pipe specimens may be affected, leading to a reduction in material fracture elongation and a decrease in their thermal and oxygen stability. Furthermore, immersion in either amine or ether organic solutions may result in the production of hydroxyl and other aging groups on the surface of the material.

Understanding the potential impact of organic substances in the soil environment on the aging of PE pipe ensures the long-term performance and safety of urban PE pipe. This research approach will provide valuable insights into improving the durability and reliability of urban PE pipes in soil environments.

The purpose of this paper is to provide the historical background of genealogical records and analyze the value of Chinese genealogical research through the study of names and genealogical resources.

The paper examines the historical evolution and value of Chinese genealogical records, with the focus on researching the Islamic Chinese names used by the people living in Guilin. The highlight of this paper includes the analysis and evolution of the Islamic Chinese names commonly adopted by the local people in Guilin. It concludes with the recommendations on emphasizing and making the best use of genealogical records to enhance the research value of Chinese overseas studies.

The paper covers the history of Islam and describes how the religion was introduced into China, as well as Muslims' ethnicity and identity. It also places focus on the importance of building a research collection in Asian history and Chinese genealogy.

This research study has a strong subject focus on Chinese genealogy, Asian history, and Islamic Chinese surnames. It is a narrow field that few researchers have delved into.

The results of this study will assist students, researchers, and the general public in tracing the origin of their surnames and developing their interest in the social and historical value of Chinese local history and genealogies.

The study of Chinese surnames is, by itself, a particular field for researching the social and political implications of contemporary Chinese society during the time the family members lived.

Very little research has been done in the area of Chinese local history and genealogy. The paper would be of value to researchers such as historians, sociologists, ethnologists and archaeologists, as well as students and anyone interested in researching a surname origin, its history and evolution.

Many users build personal projects in co-innovation community to accomplish their innovations. However, very few projects from such communities are successful and understanding of this phenomenon is limited. The purpose of this paper is to identify the factors facilitating user projects success in online co-innovation communities.

Based on the theories of persuasion and diffusion of innovation (DOI), a conceptual model is proposed to explain how project success likelihood is affected by the creator, project and user participation characteristics. Then, the model and hypotheses are tested through binary logistic regression on a secondary data set of 572 projects collected from a typical user co-innovation community, Local Motors.

The results show that creator characteristics (prior success rate), project characteristics (project popularity, length and duration) and user participation characteristics (participation users and degree) have significant and positive impacts on project success likelihood. The number of prior projects, which can hardly represent the creator’s credibility in open and unrestricted situations, has no significant influence on the project success likelihood.

This study offers project creators the keys to increase their projects successful possibility. Besides, this study recommends a new way to attract users and helps to identify creative and effective users for community practitioners.

This study expands the research scope in online co-innovation community by focusing on user personal projects. In addition, it combines persuasion theory and DOI theory to add the holistic understanding of user project success likelihood.

This paper traces the incorporation of western educational histories in the development of normal-school curricula during the late Qing Dynasty and the Republic of China (1901–1944). It uses publication networks to show how the study of comparative educational history facilitated the international circulation of knowledge in the teaching profession, and how the “uses” of educational history were shaped by larger geopolitical forces.

This paper analyzes the international exchange of texts between normal schools in China and Japan and, subsequently, between normal schools in China and the United States. A database of 107 publications in the field of western educational history that were adopted in China reveals specific patterns of textual citation, cross-reference, and canon-formation in the field of educational historiography.

With conclusions derived from a combination of social network analysis and clustering analysis, this paper identifies three broad stages in China's development of normal-school curricula in comparative educational history: “Japan as Teacher,” “transitional period” and “America as Teacher.”

Statistical analysis can reveal citation and reference patterns but not readers' understanding of the deeper meaning of texts – in this case, textbooks on the subject of western educational history. In addition, the types of publications analyzed in this study are relatively limited, the articles on the history of education in journals have not become the main objects of this study.

This paper uses both quantitative and qualitative methods to uncover the transnational circulation of knowledge in the field of comparative educational history during its formative period in China.

The purpose of this research is to investigate how postpartum mothers conduct self-disclosure on social media may obtain social support and therefore improve their depressive mood.

The authors extract variables of self-disclosure by manual coding postpartum mothers' 835 posts from a parenting social media in China. The ordinary least squares model and the binary logistic regression model are used to test the proposed hypotheses.

The study suggests that both mothers' superficial level disclosure and personal level disclosure positively affect online social support received, and the effect of personal level disclosure on social support is much greater than that of superficial level disclosure. Online social support received is related to the content of the post and reduces mothers' depressive mood. The authors further find that the association between personal level disclosure and depressive mood is fully mediated by social support.

The data are collected from a parenting social network. Although it is the major parenting social media with the most users in China, the generalizability of this model and the findings to other social media need additional research.

This study offers implications for researchers and practitioners with regard to social media uses and impacts, which also has important implications for policy and interventions for the mental health of mothers.

This paper makes theoretical contributions to the literature of social penetration theory and social support by (1) dividing self-disclosure into superficial level disclosure and personal level disclosure according to the intimacy of self-disclosure; (2) empirically investigating the direct effect of online self-disclosure on social support and the mediating effect of social support between online self-disclosure and mothers' depressive mood.

This study aims to revisit the stock price–volume relations, providing new evidence from the emerging market of Qatar. In particular, three main issues are examined using both aggregate market- and sector-level data. First, the return–volume relation and whether or not this relation is asymmetric. Second, the common characteristics of return volatility; and third, the nature of the relation between trading volume and return volatility.

The study uses the OLS and VAR modeling approaches to examine the contemporaneous and dynamic (causal) relations between index returns and trading volume, respectively, while an EGARCH-X(1,1) model is used to analyze the volatility–volume relation. The data set comprises daily index observations and the corresponding trading volumes for the entire market and the individual seven sectors of the Qatar Exchange (i.e. banks and financial services, consumer goods and services, industrials, insurance, real estate, telecommunications and transportation).

The empirical analysis reports evidence of a positive contemporaneous return–volume relation in all sectors barring transportation and insurance. This relation appears to be asymmetric for all sectors. For the market and almost all sectors, there is no significant causality between returns and volume. By and large, these findings lend support for the implications of the mixture of distributions hypothesis (MDH). Lastly, the information content of lagged volume seems to have an important role in predicting the future dynamics of return volatility in all sectors, with the industrials being the exception.

The findings provide important implications for portfolio managers and investors, given that the volume of transactions is generally found to be informative about the price movement of sector indices. Specifically, tracking the behavior of trading volume over time can give a broad portrayal of the future direction of market prices and volatility of equity, thereby enriching the information set available to investors for decision-making.

Based on both market- and sector-level data from the emerging stock market of Qatar, this study attempts to fill an important void in the literature by examining the return–volume and volatility–volume linkages.

The purpose of this paper is to analyse the dependence structure in volatility between Shanghai and Shenzhen stock market in China based on high-frequency data.

Using a multiplicative error model (hereinafter MEM) to describe the margins in volatility of China’s Shanghai and Shenzhen stock market, this study adopts static and time-varying copulas, respectively, estimated by maximum likelihood estimation method to describe the dependence structure in volatility between Shanghai and Shenzhen stock market in China.

This paper has identified the asymmetrical dependence structure in financial market volatility more precisely. Gumbel copula could best fit the empirical distribution as it can capture the relatively high dependence degree in the upper tail part corresponding to the period of volatile price fluctuation in both static and dynamic view.

Previous scholars mostly use GARCH model to describe the margins for price volatility. As MEM can efficiently characterize the volatility estimators, this paper uses MEM to model the margins for the market volatility directly based on high-frequency data, and proposes a proper distribution for the innovation in the marginal models. Then we could use copula-MEM other than copula-GARCH model to study on the dependence structure in volatility between Shanghai and Shenzhen stock market in China from a microstructural perspective.