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The purpose of this paper is to assess the hydrogen embrittlement sensitivity of carbon gradient heterostructure materials and to verify the reliability of the scratch method.

The surface-modified layer of 18CrNiMo7-6 alloy steel was delaminated to study its hydrogen embrittlement characteristics via hydrogen permeation, electrochemical hydrogen charging and scratch experiments.

The results showed that the diffusion coefficients of hydrogen in the surface and matrix layers are 3.28 × 10⁻⁷ and 16.67 × 10⁻⁷ cm²/s, respectively. The diffusible-hydrogen concentration of the material increases with increasing hydrogen-charging current density. For a given hydrogen-charging current density, the diffusible-hydrogen concentration gradually decreases with increasing depth in the surface-modified layer. Fracture toughness decreases with increasing diffusible-hydrogen concentration, so the susceptibility to hydrogen embrittlement decreases with increasing depth in the surface-modified layer.

The reliability of the scratch method in evaluating the fracture toughness of the surface-modified layer material is verified. An empirical formula is given for fracture toughness as a function of diffused-hydrogen concentration.

The purpose of this paper is to find a new method to evaluate the hydrogen embrittlement performance of heterogeneous materials and thin film materials.

The changes of hydrogen embrittlement properties of steel were studied by electrochemical hydrogen charging test and scratch test. The microstructure and properties of the alloy were analyzed by hardness tester, scanning electron microscope and three-dimensional morphology. The fracture toughness before and after hydrogen charging was calculated based on the scratch method.

The results showed that the hydrogen-induced hardening phenomenon occurs in the material after hydrogen charging. The scratch depth and width increased after hydrogen charging. The fracture toughness obtained by the scratch method showed that hydrogen reduces the fracture toughness of the material. The comparison error of fracture toughness calculated by indentation method was less than 5%.

The results show that the scratch method can evaluate the hydrogen embrittlement performance of the material. This method provides a possibility to evaluate the hydrogen embrittlement of thin-film and heterogeneous materials.

The purpose of this paper is to investigate, the effects of residual stress and microstructure on the corrosion behaviour of carburised 18CrNiMo7-6 steel in a 3.5% NaCl aqueous solution.

The electrochemical tests were conducted using an electrochemical workstation with a three-electrode system in a 3.5% NaCl aqueous solution, the residual stress of each working face was measured by a high-speed residual stress analyser, and microstructure of different carburised layers were observed scanning electron microscopy. Finally, the effect of carbon content, microstructure and residual stress on the corrosion behaviour of the steel was discussed.

The results showed that the residual compressive stress in the carburised layer initially increased and subsequently decreased with increasing depth of the carburised layer, reaching stability in the matrix layer. The electrochemical tests before and after stress reduction showed that the electrochemical impedance and the electrochemical potential increased with the reduction of residual compressive stress.

The residual compressive stress in the carburised layer initially increases and subsequently decreases with increasing carburised layer depth. The electrochemical impedance and the electrochemical potential increased with the reduction of residual compressive stress. The general relationship between electrochemical potential and residual stress was established.

The purpose of this study is to propose and test predictors of millennials’ social entrepreneurial intent (SEI), mediating mechanisms and influential contextual factors.

This study includes survey data from 1,890 respondents, 315 each from China, Mexico, Nigeria, Philippines, Russia and the USA.

Empirical results show that social entrepreneurial self-efficacy (SESE) mediated the relationship between perseverance and proactive personality and the dependent variable SEI in all six countries. Life satisfaction positively moderated this relationship among US students and negatively moderated it among Chinese students. In China dissatisfaction appears to enhance SEI, while in the US satisfaction appears to do so.

This paper identifies the mediating role of SESE and the moderating role of life satisfaction when explaining SEI, as well as providing data from millennials in six countries.

Varied shapes and sizes of different products with irregular rough surface and fragile properties give a challenge to traditional contact gripping. Single Bernoulli grippers are not suited to handle fragile objects as the impact of center negative pressure force could result in large deformation and stress which damage the materials, and they are also have some limitations for gripping objects with different large and small shapes. Thus, this paper aims to design a non-contact gripper for soft, rough-surfaced and fragile objects gripping with multi Bernoulli heads, which have optimal structures and parameters.

The compressed air is ejected into four Bernoulli heads through radial and long flow channels, then passes through four strip-shaped narrow gaps after fully developing in the annular cavity to provide negative pressure. Based on the mathematic model and the computational model, the key structural parameters affecting the gripping performance are selected, and parameters optimization of the gripper is performed by computational fluid dynamics simulation analysis and performance evaluation. The orthogonal method is used and L16 orthogonal array is selected for experimental design and optimization. The characteristics of the designed gripper are tested from the aspects of pressure distribution and lifting force.

From the applications in gripping different objects, the designed non-contact gripper can grip varied shapes and sizes of soft, rough-surfaced, fragile and sliced objects with little effect of torque.

In this paper, a non-contact gripper is designed for handling soft, rough-surfaced and fragile objects based on the Bernoulli principle. A systematic approach, which consists of modeling, simulation, optimization and measurement is provided for the non-contact gripper design and tests.

Wage reform is an important aspect of Chinese economic reform. The success of wage reform is likely to depend upon the following understanding: Neither use of the efficiency‐oriented market wage system nor use of the equity‐oriented planned wage system can solve the dual problem of economic growth and income distribution. A synergy of the two systems will therefore be needed. Such a synergetic wage system, which simultaneously solves the dual problem of production and distribution, can expedite the rise of social productivity – the fundamental mission in the preliminary stage of Chinese socialism. In other words, wages should be differentiated, and the differences should be related to workers′ effort and society′s demand for them. These differences, however, need not be very large.

This study aims to investigate the impact of geopolitical risk (GPR) on supply chain concentration (SCC) and the roles of operational capabilities and resources in this relationship.

Secondary longitudinal data from multiple sources is collected and combined to test for a direct impact of GPR on SCC. We further examine the moderating effects of firms’ operational capabilities and resources (i.e. firm resilience, operational slack and cash holding). Fixed-effect regression models are applied to test the hypotheses, followed by a series of robustness tests to check the consistency of the results.

Consistent with the tenets of resource dependence theory, our analysis reveals a significant negative impact of GPR on SCC. Moreover, we find that this adverse effect is attenuated for firms with higher levels of resilience, more operational slack and greater cash holdings. Further analysis suggests that maintaining a diversified supply chain base during heightened GPR is associated with a firm’s improved financial performance.

This study contributes to the supply chain management (SCM) literature by integrating GPR into the supply chain risk management framework. Additionally, it demonstrates the roles of diversification and operational resources in addressing GPR-induced challenges.

This paper aims to deduce a set of theory computational formula, and optimize and improve the heat conductivity of vias in printed circuit boards of electrical power apparatus.

The authors adopted numerical simulation and experimental measurement to verify the reliability of this formula.

Research result showed that 0.45 mm was the optimal bore diameter of vias; the conductivity had no obvious improvement when filling material was FR4 or Rogers, but if it was filled with texture of high thermal conductivity like soldering tine, the conductivity would improve a lot; the plating thickness of vias had a greater influence on thermal conductivity.

Through the theory computational formula, this paper studied the influence of aperture of vias, filled materials and thickness of copper plated on vias on thermal conductivity.

This paper aims to design a composite, aiming to improve the static puncture resistance through polyurethane impregnated treatment with five concentration gradients.

The relationship between polyurethane concentration, the number of polyester nonwovens, component fiber type (filament or staple) and the static puncture resistance is explored respectively and elaborately.

This study provides a new perspective to design flexible composites with better static puncture resistance, feasible preparation process as well as low cost.

The results show that the static puncture resistance of nonwovens impregnated by polyurethane is improved obviously. Meanwhile the puncture strength-T of nonwovens increases first and then decreases with the increase of the number of layers, and the maximum puncture strength-T is found at 20 layers. Moreover, the composite with filaments illustrates better mechanical resistance.

The purpose of this study is to introduce new tools to develop a more precise and focused bibliometric analysis on the field of digitalization in healthcare management. Furthermore, this study aims to provide an overview of the existing resources in healthcare management and education and other developing interdisciplinary fields.

This work uses bibliometric analysis to conduct a comprehensive review to map the use of the unified theory of acceptance and use of technology (UTAUT) and the unified theory of acceptance and use of technology 2 (UTAUT2) research models in healthcare academic studies. Bibliometric studies are considered an important tool to evaluate research studies and to gain a comprehensive view of the state of the art.

Although UTAUT dates to 2003, our bibliometric analysis reveals that only since 2016 has the model, together with UTAUT2 (2012), had relevant application in the literature. Nonetheless, studies have shown that UTAUT and UTAUT2 are particularly suitable for understanding the reasons that underlie the adoption and non-adoption choices of eHealth services. Further, this study highlights the lack of a multidisciplinary approach in the implementation of eHealth services. Equally significant is the fact that many studies have focused on the acceptance and the adoption of eHealth services by end users, whereas very few have focused on the level of acceptance of healthcare professionals.

To the best of the authors’ knowledge, this is the first study to conduct a bibliometric analysis of technology acceptance and adoption by using advanced tools that were conceived specifically for this purpose. In addition, the examination was not limited to a certain era and aimed to give a worldwide overview of eHealth service acceptance and adoption.