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In this paper, the authors aim to study the effect of hydrogen on the pitting corrosion behavior of Incoloy 825, a commonly used material for heat exchanger tubes in hydrogenated heat exchangers.

The pitting initiation and propagation behaviors were investigated by electrochemical and chemical immersion experiments and observed and analyzed by scanning electron microscope and energy dispersive spectrometer methods.

The results show that hydrogen significantly affects the electrochemical behavior of Incoloy 825; the self-corrosion potential decreased from −197 mV before hydrogen charging to −263 mV, −270 mV and −657 mV after hydrogen charging, and the corrosion current density increased from 0.049 µA/cm² before hydrogen charging to 2.490 µA/cm², 2.560 µA/cm² and 2.780 µA/cm² after hydrogen charging. The pitting susceptibility of the material increases.

Hydrogen is enriched on the precipitate, and the pitting corrosion also initiates at that location. The synergistic effect of hydrogen and precipitate destroys the passive film on the metal surface and promotes pitting initiation.

Previous research has mainly focused on the outcomes of empowering leadership, and empirical evidence on how to encourage leaders to display empowering behaviors has been overlooked, particularly from an interpersonal perspective.

Based on the integrative model of organizational trust, we investigate the relationship between employees' taking charge behaviors and empowering leadership considering the mediating role of leader trust in employees and the moderating role of risk propensity.

The results indicate that taking charge is positively associated with leader trust in employees, which influences the development of empowering leadership. Additionally, leaders' risk propensity moderates these relationships, that is, a higher level of risk propensity can enhance the promoting effect of leader trust on empowering behaviors.

This study explores the antecedents and mechanisms influencing empowering leadership and proposes the moderating effect of risk propensity. The findings not only clarify how and why employees' taking charge behaviors can stimulate empowering leadership but also offer a more comprehensive understanding of the antecedents of empowering leadership.

The purpose of this paper is to optimize and improve a bipolar charge transport (BCT) model used to simulate charge dynamics in insulating polymer materials, specifically low-density polyethylene (LDPE).

An optimization algorithm is applied to optimize the BCT model by comparing the model outputs with experimental data obtained using two kinds of measurements: space charge distribution using the pulsed electroacoustic (PEA) method and current measurements in nonstationary conditions.

The study provides an optimal set of parameters that offers a good correlation between model outputs and several experiments conducted under varying applied fields. The study evaluates the quantity of charges remaining inside the dielectric even after 24 h of short circuit. Moreover, the effects of increasing the electric field on charge trapping and detrapping rates are addressed.

This study only examined experiments with different applied electric fields, and thus the obtained parameters may not suit the experimental outputs if the experimental temperature varies. Further improvement may be achieved by introducing additional experiments or another source of measurements.

This work provides a unique set of optimal parameters that best match both current and charge density measurements for a BCT model in LDPE and demonstrates the use of trust region reflective algorithm for parameter optimization. The study also attempts to evaluate the equations used to describe charge trapping and detrapping phenomena, providing a deeper understanding of the physics behind the model.

Drawing on the work as calling theory, the purpose of this study is to explore how and when career calling promotes taking charge by focusing on the mediating effects of work meaningfulness and felt obligation and the moderating role of family-friendly human resource practice (FF-HRP).

The authors collected data from 293 supervisor–employee dyads at three time points in southeastern China. Path analysis and bootstrap method were used for hypothesis testing.

Employees' perceived career calling positively affected taking charge through work meaningfulness and felt obligation. The positive effects of career calling on work meaningfulness and felt obligation as well as the indirect effect of career calling on taking charge are stronger when employees perceive high levels of FF-HRP.

Organizational interventions should be designed to enhance employees' sense of calling, and the organization should inspire employees to take charge by awakening their perception of work meaningfulness and obligation. Moreover, FF-HRP should be implemented as a form of organizational support.

This research identifies work meaningfulness and felt obligation as mediators that link career calling to taking charge and reveals the role of FF-HRP in amplifying the positive impact of career calling.

Based on the conservation of resource theory, this paper explores the impact of differentiated transformational leadership on employees' taking charge in the context of Chinese organizations, with psychological availability as a mediator and collectivism orientation as a moderator.

The authors distributed paired questionnaires to 67 team managers and 219 team members to obtain research data and established a hierarchical linear model for the hypothesis testing.

The results show that team-focus transformational leadership has a significant positive impact on employees' taking charge, and individual-focus transformational leadership has a significant negative impact on employees' taking charge. Specifically, psychological availability plays a partial mediating role between differentiated transformational leadership and employees' taking charge. Moreover, collectivism orientation has no significant moderating effect between team-focus transformational leadership and psychological availability. But it has a significant moderating effect between individual-focus transformational leadership and psychological availability, i.e. the higher the level of collectivism orientation, the stronger the negative effect of individual-focus transformational leadership on psychological availability.

The paper notes the hierarchy of differentiated transformational leadership and divides it into team-focus transformational leadership and individual-focus transformational leadership. It also provides a new mechanism and boundary condition, i.e. differentiated transformational leadership has an impact on employees' taking charge through psychological availability and collectivism orientation is a moderator.

How does a manager’s coaching behaviour encourage taking charge behaviour among subordinates? Although prior research has found a positive association between managerial coaching behaviour and employee performance, to date few studies have examined its effect on proactive behaviours in the workplace such as taking charge. Drawing on social exchange theory (SET) and social cognitive theory (SCT), this study develops a theoretical model to examine the mediating effects of work engagement and role breadth self-efficacy (RBSE) in the relationship between managerial coaching and subordinates taking charge. Additionally, drawing on social role theory (SRT), we test whether our proposed relationships are contingent on subordinates’ gender.

We tested our proposed moderated-mediation model using empirical data collected across two waves from 196 employees within a large Malaysian services enterprise. Partial least squares structural equation modelling was used to test the proposed hypotheses.

The results revealed that managerial coaching has a significant, positive relationship with taking charge, work engagement and RBSE. However, only work engagement was found to partially mediate the relationship between managerial coaching and taking charge. Subordinates’ gender was found to positively attenuate the direct effect between managerial coaching and taking charge among females. However, the mediating effects of work engagement and RBSE in managerial coaching and taking charge were found to be not contingent on subordinates’ gender.

Finding from this study reveals that managerial coaching is useful in shaping employees' taking charge behaviour through work engagement. Hence, organisations should focus on strategies aiming to enhance managers' coaching capabilities.

This study extends the nomological networks of managerial coaching by highlighting it as a predictor of taking charge. Moreover, drawing on SET and SCT to explain the mechanism of managerial coaching and taking charge, we provide a novel perspective on how managerial coaching can influence taking charge. Specifically, we highlight the critical role of work engagement as a key mechanism that influences the relationship between managerial coaching and taking charge. Finally, we demonstrate managerial coaching as a means through which organisations can improve individual functioning.

Drawing on the “conservation of resources” theory, the current study examines the mechanisms by which individual-focused transformational leadership (i.e. individualized consideration and intellectual stimulation) is associated with employees' taking charge by investigating the mediating roles of psychological capital and thriving at work.

A three-wave research study was conducted, and the data for the study included 220 employees’-supervisors’ dyads from Indian IT (information technology) organizations. Further, confirmatory factor analysis (CFA) was utilized to assess the measurement model, and study hypotheses were tested using Process macro.

The study results showed that individual-focused transformational leadership (IFTL) is strongly associated with psychological capital, thriving at work and taking charge. The findings of Process macro analyses indicated that IFTL, directly and indirectly, impacts taking charge behavior via psychological capital and thriving at work.

The study offers significant practical implications to managers, counsellors and HRM practitioners for crafting workplace interventions to augment employees taking charge behavior. The study findings would aid HRM practitioners in designing individualized-oriented leadership programs for building employees' positive psychological capabilities and thriving experiences for taking charge.

This paper broadens the existing leadership literature by proposing new pathways through which IFTL encourages employees to take charge. Mainly, research studies need to shed more light on leadership characteristics that influence employees' positive psychological behavior, that is psychological capital and thriving at work. Consequently, this study examined the underlying mechanism through which leadership, psychological capital and thriving interact to stimulate employees taking charge behavior.

This paper aims to reduce the impact of disordered charging of large-scale electric vehicles (EVs) on the grid. EV is great significance for environmental protection, energy conservation and emission reduction to replace fuel vehicles with EVs. However, as a kind of random mobile load, large-scale integration into the power grid may lead to power quality problems such as line overload, line loss increase and voltage reduction. This paper realizes the orderly charging of electric vehicles and the safe operation of the distribution network by optimizing the dispatching scheme.

This paper takes the typical IEEE-33 node distribution system as the research object, adopts the improved particle swarm optimization algorithm and takes the minimum operation cost, the minimum environmental pollution, the minimum standard deviation of daily load, the minimum peak valley difference of load, the minimum node voltage offset rate and the minimum system grid loss rate as the optimization objectives.

Controlling the disordered charging of large-scale electric vehicles by optimizing the dispatching algorithm can realize the full consumption of renewable energy and the safe operation of the power grid.

Results show that the proposed scheme can realize the transfer of charging load in time and space, so as to stabilize the load fluctuation of distribution grid, improve the operation quality of power grid, reduce the charging cost of users and achieve the expected research objectives.

Recently, electric vehicles have been widely used in the cold chain logistics sector to reduce the effects of excessive energy consumption and to support environmental friendliness. Considering the limited battery capacity of electric vehicles, it is vital to optimize battery charging during the distribution process.

This study establishes an electric vehicle routing model for cold chain logistics with charging stations, which will integrate multiple distribution centers to achieve sustainable logistics. The suggested optimization model aimed at minimizing the overall cost of cold chain logistics, which incorporates fixed, damage, refrigeration, penalty, queuing, energy and carbon emission costs. In addition, the proposed model takes into accounts factors such as time-varying speed, time-varying electricity price, energy consumption and queuing at the charging station. In the proposed model, a hybrid crow search algorithm (CSA), which combines opposition-based learning (OBL) and taboo search (TS), is developed for optimization purposes. To evaluate the model, algorithms and model experiments are conducted based on a real case in Chongqing, China.

The result of algorithm experiments illustrate that hybrid CSA is effective in terms of both solution quality and speed compared to genetic algorithm (GA) and particle swarm optimization (PSO). In addition, the model experiments highlight the benefits of joint distribution over individual distribution in reducing costs and carbon emissions.

The optimization model of cold chain logistics routes based on electric vehicles provides a reference for managers to develop distribution plans, which contributes to the development of sustainable logistics.

In prior studies, many scholars have conducted related research on the subject of cold chain logistics vehicle routing problems and electric vehicle routing problems separately, but few have merged the above two subjects. In response, this study innovatively designs an electric vehicle routing model for cold chain logistics with consideration of time-varying speeds, time-varying electricity prices, energy consumption and queues at charging stations to make it consistent with the real world.

Promoting electric vehicles (EVs) is an effective way to achieve carbon neutrality. If EVs are widely adopted, this will undoubtedly be good for the environment. The purpose of this study is to analyze the impact of network externalities and subsidy on the strategies of manufacturer under a carbon neutrality constraint.

In this paper, the authors propose a game-theoretic framework in an EVs supply chain consisting of a government, a manufacturer and a group of consumers. The authors examine two subsidy options and explain the choice of optimal strategies for government and manufacturer.

First, the authors find that the both network externalities of charging stations and government subsidy can promote the EV market. Second, under a relaxed carbon neutrality constraint, even if the government’s purchase subsidy investment is larger than the carbon emission reduction technology subsidy investment, the purchase subsidy policy is still optimal. Third, under a strict carbon neutrality constraint, when the cost coefficient of carbon emission reduction and the effectiveness of carbon emission reduction technology are larger, social welfare will instead decrease with the increase of the effectiveness of emission reduction technology and then, the manufacturer’s investment in carbon emission reduction technology is lower. In the extended model, the authors find the effectiveness of carbon emission reduction technology can also promote the EV market and social welfare (or consumer surplus) is the same whatever the subsidy strategy.

The network externalities of charging stations and the subsidy effect of the government have a superimposition effect on the promotion of EVs. When the network effect of charging stations is relatively strong, government can withdraw from the subsidized market. When the network effect of charging stations is relatively weak, government can intervene appropriately.

Comparing previous studies, this study reveals the impact of government intervention, network effects and carbon neutrality constraints on the EV supply chain. From a sustainability perspective, these insights are compelling for both EV manufacturers and policymakers.