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The purpose of this paper is to evaluate the effect of micro-nano mixed super-hydrophobic structure on corrosion resistance and mechanism of magnesium alloys.

A super-hydrophobic surface was fabricated on AZ91 and WE43 magnesium alloys by laser etching and micro-arc oxidation (MAO) with SiO₂ nanoparticles coating and low surface energy material modification. The corrosion resistance properties of the prepared super-hydrophobic surfaces were studied based on polarization curves and immersion tests.

Compared with bare substrates, the corrosion resistance of super-hydrophobic surfaces was improved significantly. The corrosion resistance of super-hydrophobic surface is related to micro-nano composite structure, static contact angle and pretreatment method. The more uniform the microstructure and the larger the static contact angle, the better the corrosion resistance of the super-hydrophobic surface. The corrosion resistance of super-hydrophobic by MAO is better than that of laser machining. Corrosion of super-hydrophobic surface can be divided into air valley action, physical shielding, pretreatment layer action and substrate corrosion.

The super-hydrophobic coatings can reduce the contact of matrix with water so that a super-hydrophobic coating would be an effective way for magnesium alloy anti-corrosion. Therefore, the corrosion resistance properties and mechanism of the prepared super-hydrophobic magnesium alloys were investigated in detail.

The purpose of this paper is to present an oligopolistic version of the cobweb model that departs from the strict assumptions of perfect competition in the traditional cobweb model.

Introducing a model where n identical producers engage in Cournot competition, with output decisions influencing market prices. The paper retains the original assumptions of naive expectations and a linear model where price expectations of Cournot competitors are made simultaneously with production decisions. The investigation focuses on the model's behavior as the number of producers decreases or industry concentration increases. The authors also show empirical evidence when drawing the data from the pig sector in China and the USA.

The findings indicate that the cobweb model undergoes a transition from divergent to continuous and even convergent as the number of producers decreases or industry concentration increases. The incorporation of costs related to entry and exit from the market contributes to achieving a more stable equilibrium state.

The cobweb model has been primarily studied in an idealized market structure of perfect competition, and the assumptions that they share are not obviously appropriate to many agriculture markets. This study presents an alternative version of the cobweb model in an oligopolistic market that relaxes the strict assumptions of perfect competition. The authors show the dynamics of reduced competitor numbers or increased industry concentration on the convergence of the cobweb model based on subtle variations in parameters.

The purpose of this paper is to propose an overall deformation rolling mechanism based on double four-link mechanism. The double quadrilateral mobile mechanism (DQMM) has two switchable working modes which can be used to traverse different terrains or climb over obstacles.

The main body of the DQMM is composed of a double four-link mechanism which sharing a public link and two symmetrical steering platforms which placed at both ends of the four-link mechanism. The steering platforms give the DQMM not only steering ability but also reconnaissance ability which can be achieved by carrying sensors such as cameras on steering platforms. By controlling the deformation of the DQMM, it can switch between two working modes (tracked rolling mode and obstacle-climbing mode) to achieve the functions of rolling and obstacle-climbing. Dynamic simulation model was established to verify the feasibility.

Based on the kinematics analysis and simulation results of the DQMM, its moving function is realized by the tracked rolling mode, and the obstacle-climbing mode is used to climb over obstacles in structured terrains such as continuous stairs. The feasibility of the two working modes is verified on a physical prototype.

The work of this paper is a new exploration of applying “overall closed moving linkages mechanism” to the area of small mobile mechanisms. The adaptability of different terrains and the ability of obstacle-climbing are improved by the combination of multi-modes.

The purpose of this paper is to propose a deformable two-wheel-like mobile mechanism based on overconstrained mechanism, with the abilities of fast rolling and obstacle surmounting. The drive torque of the multi-mode motions is generated by self-deformation. Moreover, the analyses of feasibility and locomotivity of two mobile modes are presented.

The main body of the two-wheel-like mobile mechanism is a kind of centrally driven 4 R linkages. The mobile mechanism can achieve the capabilities of fast rolling and obstacle surmounting through integrating two mobile modes (spherical-like rolling mode and polyhedral-like obstacle-surmounting mode) and can switch to the corresponding mode to move or surmount obstacles. The mobility and kinematics of the mobile modes are analyzed.

Based on the results of kinematics analysis and dynamics analysis of the wheel-like mechanism, the spherical-like rolling mode has the capability of fast rolling, and the polyhedral-like obstacle-surmounting mode has the capability of surmounting different obstacle heights by two submodes (quasi-static obstacle-surmounting submode and dynamic obstacle-surmounting submode). The proposed concept is verified by experiments on a physical prototype.

The work presented in this paper is a novel exploration to apply bar linkages in the field of scout. The two-wheel-like mobile mechanism improves the torque imbalance of bar linkages by centrally driven method, removes the rear support structures of the traditional two-wheeled mechanisms by self-deformation and increases the height of obstacle surmounting by mode switching angle.

The purpose of this paper is to investigate the impact of various decision-making approaches and government subsidies on supply chain performance, aiming to enhance the profits of disposal firms and retailers as well as to improve social welfare.

In this paper, a two-echelon biomass supply chain composed of a disposal firm and a retailer is developed. Firstly, considering the effects of government subsidies, we analyze biofuels prices, corporate social responsibility levels, social welfare and supply chain profitability under centralized and decentralized decision-making scenarios, respectively. Furthermore, we assess how subsidies influence pricing, market participation, profitability and social welfare. Secondly, we propose a revenue sharing–cost sharing contract to enhance the profits of the disposal firm and retailer. Thirdly, we extend the supply chain to a disposal firm and two retailers and explore the impact of competition intensity on corporate decision-making behavior. Finally, numerical analysis is conducted by taking one biomass energy firm as an example to support the results.

Our research finds that (1) Equilibrium strategies under the centralized decision-making scenario are greater than those under the decentralized decision-making scenario. Centralized decision-making can increase market demand and consumer surplus. (2) Government subsidies can promote corporate social responsibility levels, despite causing a slight increase in retail price for biofuels. When market competition intensifies, companies usually reduce their investment in CSR, and this trend is particularly pronounced in the absence of subsidies. (3) In both the decentralized and the centralized decision-making scenarios, increasing conversion rates and the CSR coefficient can significantly increase the overall profitability and social welfare.

A three-echelon biomass supply chain involving collection station, disposal firm and retailer can be studied in the future.

By examining the effects of subsidies on CSR engagement and market outcomes, our study contributes valuable insights into policy design for promoting sustainable practices in biomass industries.

The purpose of this paper is to establish a new dynamic coupled discrete-element contact model used for investigating fresh concrete with different grades and different motion states, and demonstrate its correctness and reliability according to the rheological property results of flow fresh concrete in different working states through simulating the slump process and mixing process.

To accurately express the motion and force of flowing fresh concrete in different working states from numerical analysis, a dynamic coupled discrete-element contact model is proposed for fresh concrete of varying strength. The fluid-like fresh concrete is modelled as a two-phase fluid consisting of mortar and aggregate. Depending on the contact forms of the aggregate and mortar, the model is of one of the five types, namely, Hertz–Mindlin, pendular LB contact, funicular mucous contact, capillary LB contact or slurry lift/drag contact.

To verify the accuracy of this contact model, concrete slump and cross-vane rheometer tests are simulated using the traditional LB model and dynamic coupled contact model, for five concrete strengths. Finally, by comparing the simulation results from the two different contact models with experimental data, it is found that those from the proposed contact model are closer to the experimental data.

This contact model could be used to address issues such as (a) the mixing, transportation and pumping of fresh concrete, (b) deeper research and discussion on the influence of fresh concrete on the dynamic performance of agitated-transport vehicles, (c) the behaviour of fresh concrete in mixing tanks and (d) the abrasion of concrete pumping pipes.

To accurately express the motion and force of flowing fresh concrete in different working states from numerical analysis, a dynamic coupled discrete-element contact model is proposed for fresh concrete of varying strength.

The purpose of this paper is to verify and extend the application of the policy acceptance model (PAM) in the field of green behavior. Under the PAM framework, the authors develop and empirically examine on how employee perception of corporate green policy (perceived ease of use and perceived usefulness) increases the acceptance of corporate green policy, which further leads to two types of employee green behavior. The authors also test the moderating roles of moral reflectiveness and performance orientation on these relationships.

The authors collected complete survey data from 223 work professionals in this study. Multiple regression method was used to test the hypotheses.

The results showed that there were significant positive impacts of two types of employee perceptions of corporate green policy (perceived ease of use and perceived usefulness) on their attitudes toward corporate green policy. Second, this study reported positive relationships between employees’ attitudes toward corporate green policy and their two types of green behavior. Finally, supplemental analyses supported moderated mediation models, that is, moral reflectiveness and performance orientation, respectively, and moderated indirect effects of employee perceptions on green behaviors through attitude toward corporate green policy.

The data came from a narrow demographic population, which restricts the generalizability of the findings and also raises questions about the specificity of green behaviors manifest in different industries. Besides, this study used cross-sectional, self-reported data, which limits our ability to draw causal conclusions.

Companies can shape employee perceptions regarding the usefulness and ease of corporate green policy to induce and consolidate employees’ task-related and proactive green behaviors.

This research will help companies to pay more attention to employees’ reflections and attitudes toward green policies, thus effectively promoting employees’ green behavior in the workplace. These actions will further promote the green development of the economy and society.

The authors extend the PAM framework to the area of green behavior. The PAM is applied to a more micro level of corporate green policy. Further, this paper points out that employees’ instrumental value (performance orientation) and moral trait (moral reflectiveness) moderate the impact of employees’ policy perceptions on their green behaviors.

The purpose of this paper is to investigate the relationship between union practices and two types of employees’ extra-role behaviors, namely, union citizenship behavior (UCB) and employee voice (EV), and the mechanisms that mediate this relationship.

Using matched data from 46 union leaders and 279 union members of 33 workplaces in China, this study utilized multilevel structural equation modeling to test the cross-level influences of union practices on employees’ extra-role behaviors and the mediation effects.

The results show that (1) union practices have a positive impact on employees’ UCB and EV, and (2) union practices increase UCB and EV through the improvement of industrial relations (IR) climate at the workplace level, as well as union commitment (UC) and union instrumentality (UI) at the individual level.

Although the authors collected data from multi-sources (i.e. union leaders and members), the cross-sectional data of this study limited the ability to make casual inferences.

This study contributes to the literature by providing theoretical explanation and empirical evidence to illustrate the role of union practices in increasing the extra-role behaviors of employees (i.e. UCB and EV). This is of particular importance in elaborating the effectiveness of enterprise unions under the recent reforms in China. In addition, the authors also unpacked the antecedents of extra-role behaviors in the union context by investigating how IR climate, UC and UI mediate the relationship between union practices and extra-role behaviors of employees.

Employee engagement has received a considerable amount of research attention over the last decade. However, most of the research has been on job or work engagement. Much less attention has been given to organization engagement, which is a distinct but related target of employee engagement. In this paper, we review the research on organization engagement and identify how it has been measured, its antecedents and consequences and how it compares to job engagement.

This paper provides a narrative review of 40 studies that have measured organization engagement. Most of these studies have been published in the last five years, and they come from 20 different countries. The majority of studies also measured job or work engagement.

Most studies used Saks' (2006) measure of organization engagement. Many antecedents have been found to be related to organization engagement; however, those most often studied and consistently related to organization engagement are organizational-related resources such as perceived organizational support (POS), justice perceptions, corporate social responsibility (CSR), organizational structural factors, organizational climate and HR practices. Organization engagement has been found to be positively related to job satisfaction, organizational commitment, organizational citizenship behavior (OCB), job performance and organizational performance and negatively related to intention to quit. Organization engagement has also been found to partially or fully mediate the relationship between antecedents and consequences. In comparison to job engagement, organization engagement scores tend to be lower, and there are meaningful differences in the antecedents and consequences of organization engagement and job engagement. A number of studies found that organization engagement was more strongly related to several of the consequences than job engagement.

The results of this review indicate that organization engagement is as important if not more important than job engagement when it comes to its relationship to some of the consequences of employee engagement. Organizations should include a measure of organization engagement in employee surveys and focus on improving organization engagement by providing a supportive work environment, ensuring that employees have positive perceptions of justice, increasing CSR initiatives, providing a variety of human resources (HR) practices and improving organizational climate.

This paper provides the first comprehensive review of research on organization engagement and offers a new model of the antecedents and consequences of organization engagement and compares organization engagement to job engagement.

A novel grafted temperature-responsive ReO₄⁻ Imprinted composite membranes (Re-ICMs) was successfully prepared by using polyvinylidene fluoride (PVDF) resin membranes as substrates, this study aimed to separate and purify ReO effectively.

Re-ICMs were synthesized by PVDF resin membranes as the substrate, acrylic acid (AA), acrylamide (AM), ethylene glycol dimethacrylate (EGDMA) were functional monomers. The morphology and structure of Re-ICMs were characterized by scanning electron microscope and Fourier transform infrared spectroscopy.

The maximum adsorption capacity toward ReO₄⁻ was 0.1,163 mmol/g and the separation decree had relation to MnO₄⁻ was 19.3. The optimal operation conditions were studied detailedly and the results as follows: the molar ratios of AA, AM, EGDMA, ascorbic acid, NH4ReO₄, were 0.8, 0.96, 0.02, 0.003 and 0.006. The optimal time and temperature were 20 h and 40°C, respectively. The Langmuir and pseudo-second-order models were fit these adsorption characteristics well.

Rhenium (Re) is mainly used to chemical petroleum and make superalloys for jet engine parts. This study was representing a technology in separate and purify of Re, which provided a method for the development of the petroleum and aviation industry.

This contribution provided a novel method to separate ReO₄⁻ from MnO₄⁻. The maximum adsorption capacity was 0.1163 mmol/g at 35°C and the adsorption equilibrium time was within 2 h. Meanwhile, the adsorption selectivity rate ReO₄⁻/MnO₄⁻ was 19.3 and the desorption rate was 78.3%. Controlling the adsorption experiment at 35°C and desorption experiment at 25°C in aqueous solution, it could remain 61.3% of the initial adsorption capacity with the adsorption selectivity rate of 13.3 by 10 adsorption/desorption cycles, a slight decrease, varied from 78.3% to 65.3%, in desorption rate was observed.