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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.

Based on the stressor-detachment theory, this study aims to investigate the effect of daily customer mistreatment on proactive service performance and ego depletion, mediated by psychological detachment inhibition during the evening. Additionally, this study endeavors to investigate the dual moderating role of prosocial motivation.

A time-lagged, diary daily survey involving 74 participants over 8 consecutive workdays was conducted to test the hypotheses.

The findings indicate that the psychological detachment inhibition during the evening of Day t mediates the impact of Day t’s customer mistreatment on Day t + 1’s proactive service performance and ego depletion. Furthermore, although prosocial motivation was found to intensify the impact of customer mistreatment on psychological detachment inhibition, it alleviated the negative association between psychological detachment inhibition and proactive service performance.

When employees experience customer mistreatment, hospitality managers should not only provide emotional reassurance and resolve any related issues promptly but also encourage employees to engage in activities that distract them and help them to relax and recharge, especially for those who exhibit high prosocial motivation. Moreover, hiring employees with high prosocial motivation is recommended for hospitality organizations to enable them to maintain high service performance.

This study focuses on psychological detachment inhibition during the evening linking within-person design and daily spill-over impact, enriching the mechanisms through which the repercussions of daily customer mistreatment extend beyond the immediate workday and affect individuals’ outcomes. This study also expands upon the existing literature by clarifying the dual aspects – both detrimental and beneficial – of prosocial motivation.

Despite mounting evidence that job insecurity triggers counterproductive work behavior (CWB), the underlying mechanism within the association in hybrid employment remains unknown. This study aims to investigate turnover intention as a mediator in the association between job insecurity and CWB, as well as the differences between permanent and contract workers concerning the effect of job insecurity on employees’ CWB.

Dyadic data were collected from 213 workers (103 contract and 110 permanent workers) and their supervisors, who were employed in one of the three branches of a Chinese state-owned enterprise, respectively, located in Hunan, Shenyang and Xinjiang.

This study found that job insecurity was positively related to CWB, in which turnover intention acted as a partial mediator. Employment status acted as a moderator between job insecurity and CWB.

First, this study extends the theoretical knowledge concerning how job insecurity activates CWB by identifying turnover intention as a mediating mechanism. To the best of the authors’ knowledge, this is the first study to explore the mediating role of turnover intention in terms of job insecurity and CWB. Second, this research expands the understanding of the relation between job insecurity and CWB by investigating this link in the case of contract workers versus permanent workers. Finally, this paper aims to provide an understanding of why contract workers and permanent workers may differ in their reactions to job insecurity.