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This paper aims to study the synergistic lubrication effects of Sn–Ag–Cu and MXene–Ti₃C₂ to improve the tribological properties of M50 bearing steel with microporous channels.

M50 matrix self-lubricating composites (MMSC) were designed and prepared by filling Sn–Ag–Cu and MXene–Ti₃C₂ in the microporous channels of M50 bearing steel. The tribology performance testing of as-prepared samples was executed with a multifunction tribometer. The optimum hole size and lubricant content, as well as self-lubricating mechanism of MMSC, were studied.

The tribological properties of MMSC are strongly dependent on the synergistic lubrication effect of MXene–Ti₃C₂ and Sn–Ag–Cu. When the hole size of microchannel is 1 mm and the content of MXene–Ti₃C₂ in mixed lubricant is 4 wt.%, MMSC shows the lowest friction coefficient and wear rate. The Sn–Ag–Cu and MXene–Ti₃C₂ are extruded from the microporous channels and spread to the friction interface, and a relatively complete lubricating film is formed at the friction interface. Meanwhile, the synergistic lubrication of Sn–Ag–Cu and MXene–Ti₃C₂ can improve the stability of the lubricating film, thus the excellent tribological property of MMSC is obtained.

The results help in deep understanding of the synergistic lubrication effects of Sn–Ag–Cu and MXene–Ti₃C₂ on the tribological properties of M50 bearing steel. This work also provides a useful reference for the tribological design of mechanical components by combining surface texture with solid lubrication.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2023-0381/

This paper aims to predict and evaluate the wear rate of TiAl-2 Wt.% MoO₃ tabular crystals (TMCs) using the Newton interpolation methods.

The friction and wear behaviors of TMC were examined using pin-on-disc apparatus at different times, namely, 1,200, 2,400, 3,600, 4,800 and 6,000 s. The wear rates of five different times as interpolation nodes were measured and calculated by electron probe microanalysis (EMPA) and field emission electron microscope (FESEM). Then, the prediction formula of wear rate was constructed using the Newton interpolation method. The accuracy of the prediction formula and the relationship with friction layer and worn surface are verified for evaluating the reliability of the prediction formula.

The prediction formula shows a similar variation trend of TMC as the experimental results, indicating that the prediction formula can forecast the wear rate and working condition of TMC. Moreover, the microstructures of friction layer and worn surface also have a strong impact on the prediction formulas.

The prediction formulas of the Newton interpolation polynomial can be adopted to predict working longevity in the mechanical components, which can guide the practical engineering application in industrial fields.

The purpose of this paper is to examine how households’ engagement in concurrent business (CB), which is measured by the contribution of off-farm income to household income, affects the farm size–technical efficiency (TE) relationship in Northern China.

This paper applies a stochastic frontier analysis method to analyze data on 1,006 rural households collected from four major wheat-producing provinces in Northern China, adopting a translog specification for the underlying production function.

The analysis yields three findings. First, the farm size–TE relationship is inverted U-shaped for all CB engagement levels higher than 5 percent, and the most technically efficient farm size increases with the level of household CB engagement. Second, how TE varies with the level of CB engagement depends on farm size: an inverted-U relationship for relatively small farms (<10μ), a positive relationship for middle-size farms (10–20μ), and a negative relationship for large farms (>20μ). Finally, the overall TE score, 0.88, suggests that wheat output can be increased by 12 percent in Northern China if technical inefficiency were eliminated.

Unlike most previous studies that examine the impacts of farm size and households’ off-farm business involvement separately, this paper examines how these two factors interact with each other.

The spinel NiFe₂O₄ has been identified as being a potentially successful anti‐corrosion ceramic that can be used in aluminium electrolysis under molten salt corrosive conditions (970°C). The evaluation and fabrication processing of NiFe₂O₄ has been studied in this paper. According to the analysis and comparison of material properties, it has been concluded that fabrication technology for making anti‐corrosion electrode material would not be exceptionally difficult and therefore that the material has a strong potential for use in this service.

This paper applies the knowledge-based genetic algorithm to solve the optimization problem in complex products technological processes.

The knowledge-based genetic algorithm (KGA) is defined as a hybrid genetic algorithm (GA) which combined the GA model with the knowledge model. The GA model searches the feasible space of optimization problem based on the “neighborhood search” mechanism. The knowledge model discovers some knowledge from the previous optimization process, and applies the obtained knowledge to guide the subsequent optimization process.

The experimental results suggest that the proposed KGA is feasible and available. The effective integration of GA model and knowledge model has greatly improved the optimization performance of KGA.

The technological innovation of complex products is one of effective approaches to establish the core competitiveness in future. For this reason, the KGA is proposed to the technological processes optimization of complex products.

Purpose – Integrating a gender perspective with a world-system theory, we examine how the recent global economic crisis in China has differential impact on female and male migrant workers. We analyzes how this gendered impact is compounded by intersectionality that results in multiple inequalities shaping their work, identity, power relationship, agency, and family lives.

Method – Our analyses were primarily drawn from 14 surveys of major provinces with higher migration rates, and were supplemented by personal narratives and interviews of migrant workers.

Findings – The political-economic analysis of the world-system demonstrates how the intricate linkages among declines in trade, finance, and production led to the economic crisis in China, with more detrimental effects on women migrant workers than their male counterparts. The intersectionality of gender, class, age/generation, and regional differences has played out in the state-regulated process of migration, configuring and reconfiguring the organization of capital, labor, and production and determining unequal gender relations, class dynamics, citizenship, employment, and family life. Conditioned by complex inequalities, some affected migrant workers, far from being victimized, have demonstrated agency, resilience, and a spirit of resistance.

Research and practical implications – More disaggregated data by gender are needed to understand the full range of differential crisis effects on diverse women and men workers.

Originality/value of the study – This study suggests the importance of considering gender-sensitive policies and a gender mainstreaming approach to addressing gender inequality and improving migrant workers’ lives for their empowerment.

Safety climate plays an important role in the high-risk construction industry. Advances have been made in the understanding of construction safety climate in terms of four interrelated themes, specifically, its definition, measurement, antecedents and consequences. However, knowledge remains fragmented as the studies are scattered, and a systematic review covering these four themes is lacking. To address this research gap, this study aims to perform a systematic literature review of construction safety climate literature regarding the four themes.

Following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) protocol guidelines, 178 eligible articles were obtained. This study provided thematic analysis of the 178 papers to identify what is known and what is not yet fully known regarding the four themes of construction safety climate. This study also conducted a descriptive analysis to identify the influential scholars, keywords, theories and research methods used by the literature, and finally presented an integrative framework directing future research.

The literature has not reached a consensus on the definition and measurement of construction safety climate. While it has identified the impact of safety climate on both behavioral and accident consequences, it has paid less attention to the antecedents and their underlying mechanisms regarding safety climate. Fang D. and Lingard H. are identified as the most influential authors in this field. “Questionnaire” and “safety behavior” are the keywords most closely related to safety climate. Unfortunately, the existing evidence for the causal relationships between safety climate and its antecedents and consequences is weak, as many studies lack clear theoretical substance, use a concurrent research design and focus only on individual-level climate perceptions. Finally, to support the development of construction safety climate around the four themes, potential research directions and research methods supporting them are illustrated.

This review makes contributions by integrating existing construction studies covering its definition, measurement, antecedents and consequences. This review also makes contributions to specific themes: no review exists on the antecedents of construction safety climate, and this review fills that gap; with regard to consequences, the existing reviews focus either on safety outcomes or safety behavior, but this review included both of them and further elaborated the different theories underpinning the relationships between safety climate and them. It is hoped that this systematic review will be helpful to the research community toward developing a nomologic network and promoting knowledge integration with respect to construction safety climate.

Collaboration is essential to BIM-enabled construction projects (BECPs). To facilitate collaboration, various strategies have been proposed. Usually, project team adopts single collaboration strategy for convenience. However, BIM-based collaboration is rather dynamic and exposed to a lot of barriers and risks, which easily changes collaboration conditions among partners. Therefore, better understanding of collaboration conditions in BECPs is crucial to develop flexible and suitable strategies. To fill in the gap, this study intends to identify typical collaboration profiles in BECPs and develop a profile-oriented strategy selection framework.

This study establishes a six-dimensional collaborative behavior matric based on a comprehensive literature review to profile collaboration. Then a questionnaire survey is conducted to collect the collaboration data from 162 BECPs in China. Finally, latent profile analysis (LPA) is utilized to identify the typical collaboration profiles in BECPs.

Through LPA, four profiles are identified, including restricted collaboration profile, smarmy collaboration profile, intuitive collaboration profile, and modest collaboration profile. A profile-oriented strategy selection framework is also established to match strategies with collaboration profiles. Two major categories of strategies are proposed to promote these collaboration profiles including trust building and elevating strategies and collaborative behaviors facilitating strategies.

These identified profiles can provide an insightful understanding on the diversified collaboration conditions in BECPs.

The profile-oriented strategy selection framework will help managers develop strategies flexibly to promote collaboration in BECPs.

This study validates four typical collaboration profiles in BECPs. Moreover, a profile-oriented strategy selection framework is also established for collaboration facilitation in BECPs.

This in vitro study aims to explore the effects of selective laser melting (SLM) process parameters on the accuracy of the intaglio surface of cobalt–chromium alloy (Co–Cr), commercially pure titanium (CP Ti) and titanium alloy (Ti–6Al–4V) maxillary removable partial denture (RPD) frameworks and optimize these process parameters.

Maxillary RPD framework specimens designed on a benchmark model were built. The process parameters, including contour scan speed and laser power, infill scan speed and laser power, hatch space, build orientation and metallic powder type, were arranged through the Taguchi design. Three-dimensional deviations of the clasps area, connector area and overall area of maxillary RPD frameworks were analyzed by using root mean square (RMS) as a metric. One-way analyses of variance with the above RMSs as the dependent variable were carried out (α = 0.05).

Maxillary RPD frameworks built horizontally had a more accurate intaglio surface than those built at other orientation angles; CP Ti or Ti–6Al–4V maxillary RPD frameworks had a more accurate intaglio surface than Co–Cr ones; the Maxillary RPD framework built with a higher infill scan speed and lower infill laser power had the more accurate intaglio surface than the one built with other levels of these two process parameters.

A novel benchmark model for evaluating the accuracy of the intaglio surface of maxillary RPD frameworks manufactured by SLM is proposed. The accuracy of the intaglio surface of maxillary RPD frameworks can be improved by adjusting SLM process parameters. The optimal setting of process parameters concerning the accuracy of the intaglio surface of maxillary RPD frameworks was given.

The purpose of this paper is to consider the use and application of the “wire‐beam electrode” method to evaluate the effectiveness of corrosion inhibitors used in concrete.

The corrosion behavior of reinforcing bars in concrete was studied by simulating the 4×4 wire‐beam electrode array. Different inhibitors, such as NaNO₂, NaNO₂ + Na₂CO₃ and NaNO₂ + aniline, were added to reinforced concrete. By measuring the open‐circuit potential of an iron wire, the impact of different inhibitors on the corrosion of rebar in the concretes was studied after immersion in 3 percent NaCl solution.

Best protection was achieved by adding NaNO₂ and aniline as inhibitors jointly to the concrete, as this combination maintained the open‐circuit potential within the passivation range at all times, so ensuring the integrity of the passive membrane.

By addition of this combination of the inhibitors, the compactibility of the cement concrete structure can be increased, thereby protecting the reinforcing bar against the external corrosive media. It is a technical approach that can deliver long‐term protection of the steel, with the best practical and economic advantage.