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The purpose of this paper was to compare the electrochemical homogeneity of AZ91D after various heat treatment processes, and its influence on the growth, composition, microstructure and corrosion resistance of phosphate conversion coatings.

The electrochemical activity of different heat-treated Mg alloys was evaluated via scanning vibrational electrode technique; the characterization of the microstructure and phase composition of coatings was conducted using a scanning electron microscope and X-ray diffraction. The corrosion resistance was evaluated by electrochemical tests and accelerated neutral salt spray tests.

T6 treatment increased the electrochemical homogeneity, while T4 treatment decreased the microstructure homogeneity of AZ91D magnesium alloy, due to the existence of residual Al-Mn impurity phase. The phosphate conversion coating (PCC) on T6 heat-treated Mg alloys showed the most compact microstructure and the best corrosion resistance, while the coating on the T4 heat-treated Mg alloy exhibited the worst microstructure and corrosion resistance.

The microstructure and protectiveness of coatings are related to the homogeneousness of Mg alloy: an Mg substrate with a more heterogeneous electrochemical reactivity yields a PCC with less protectiveness, which could be explained by the difference of precipitation kinetics at the metal/electrolyte interface.

There is coupling between the branches of mobile parallel robots, similar to traditional parallel mechanisms, but there is currently relatively little research on the coupling problem between the branches of mobile parallel robots.

This study optimizes the coupling analysis method of traditional parallel mechanisms, treats the mobile parallel mechanism as a whole, takes the motion of the active pair as input and the overall motion of the mobile parallel mechanism as output and analyzes the input–output characteristics of the mobile parallel mechanism. Moreover, this study applies this theory to a mobile parallel mechanism, designs control logic and finally conducts simulation and physical verification.

This study proposes a coupling analysis method suitable for parallel mobile robots and designs the control logic of their active pair based on the results of their coupling analysis. This study designs a multimode variable coupling parallel mobile robot, which can change the coupling of the mechanism by changing its own branch chain structure, so that it can switch between different coupling configurations to meet the different needs brought by different terrains.

The work presented in this paper propose a method for analyzing the coupling of mobile parallel robots and simplify their control logic by applying coupling theory to the design of mobile parallel robots. This study conducts simulation and physical experiments, thereby filling the gap in the coupling analysis of parallel mobile robots and laying the foundation for the research of uncoupled parallel mobile robots.

This study aims to make the mobile robot better adapt to the patrol and monitoring in industrial field substation area, a multi-mode mobile carrying mechanism which can carrying data collector, camera and other equipment is designed.

Based on the geometric axis analysis and interference analysis, the multi-mode mobile carrying mechanism is designed. The screw constraint topological theory and zero-moment point (ZMP) theory is used to kinematic analysis in mechanism mobile process.

The mobile carrying mechanism can realize the folding movement, hexagonal rolling and quadrilateral rolling movement. A series of simulation and prototype experiment results verify the feasibility and actual error of the design analysis.

The work of this paper provides a mobile carrying mechanism for carrying different data acquisition equipment and surveillance camera in industrial field substation zone. It has excellent folding performance and mobile capabilities. The mobile carrying mechanism reduces the workload of human being and injuries suffered by workers in industrial substation area.

The purpose of this study is to evaluate the role of encapsulation pH and iron source on the anchorage mode and performance of iron oxide-encapsulated aluminium pigments.

The coloured waterborne aluminium pigments were prepared at pH 5-7.5 by using FeSO₄ and FeCl₃ as iron source. The anchorage mode of iron oxides on aluminium was characterized using optical microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction. Furthermore, the pigmentary performance was characterized through anticorrosion test and multi-angle spectroscopy.

Diaspore and boehmite could form from H₂O₂ oxidizing aluminium. Both low pH and FeSO₄ systems are beneficial for diaspore, inducing green rust anchor on the aluminium to form goethite. Either in FeSO₄ or FeCl₃ system, slightly high pH is beneficial for the formation of boehmite, which occurred together with ferrihydrite to form denser coating with yellowness and excellent anticorrosion property. At pH above 7, the formation of dendritic iron oxide is detrimental to the anticorrosion property and the glossiness.

Only FeSO₄·7H₂O and FeCl₃·6H₂O as iron sources were explored.

The investigation results provide theoretical basis to obtain excellent chromatic waterborne aluminium pigments.

The method for investigation of encapsulation mechanism by surveying the structure of iron oxides on aluminium, which varies with the pH of the system and iron sources, is novel.

The purpose of this paper is to put forward a nvew reconfigurable multi-mode walking-rolling robot based on the single-loop closed-chain four-bar mechanism, and the robot can be changed to different modes according to the terrain.

Based on the topological analysis, singularity analysis, feasibility analysis, gait analysis and the motion strategy based on motor time-sharing control, the paper theoretically verified that the robot can switch between the four motion modes.

The robot integrates four-bar walking, self-deforming and four-bar and six-bar rolling modes. A series of simulation and prototype experiment results are presented to verify the feasibility of multiple motion modes of the robot.

The work presented in this paper provides a good theoretical basis for further exploration of multiple mode mobile robots. It is an attempt to design the multi-mode mobile robot based on single loop kinematotropic mechanisms. It is also a kind of exploration of the new unknown movement law.

This paper aims to review bright sides of corporate social responsibility (CSR) and touches on its dark sides, providing researchers and CSR-driven lay readers with a starting point for further contributions and discussions. The paper also outlines a conceptual perspective about CSR scale development relevant to the uncertain times Syrian Arab Republic is still facing.

With a top ten-journal set indexed in social science citation index (SSCI), the current paper reviewed dozens CSR-references. In different search settings, the paper also included other authoritative references relevant.

CSR, whose bright side is still in the lead, is a significant working philosophy that can keep stakeholders posted on the extent to which organizations can sustain businesses and protect society's welfare at interconnected levels (economic, social, ethical and environmental, among others).

The review at hand has only covered the tip of the CSR iceberg.

Investing in CSR transparently could lead to a promising sustainability.

With transparent CSR information, stakeholders (including the public and policymakers) could make an informed decision regarding the extent to which organizations with CSR could protect their well-being.

The current review makes an authoritative reference point new in the CSR literature. In addition, it bridges a research gap not yet studied – by bringing a roadmap outlining a potential CSR-scale development that could cope with the postwar reconstruction phase (an example of which being Syrian Arab Republic).

This paper aims to present a longitudinal and visualising study using bibliometric approaches to depict the emerging trends and research hotspots within the mobile information system domain.

Publications included in the Web of Science (WoS) database for 2001–2021 are reviewed and analysed on various aspects through coauthorship, cocitation and co-occurrence analysis. The analyses are conducted using VOSViewer, a scientific visualisation software program.

Academic publications related to mobile information systems fluctuated at a low level during the initial part of the 21st century and have grown rapidly in number in the past decade. The USA and China are the leading contributors to these publications and hold dominant positions in the obtained collaboration network. Computer science, engineering and telecommunications are the top three research areas in which mainstream mobile information system research occurs. Moreover, medical informatics and health-care science services have gradually become new research hotspots.

This study provides a systematic and holistic account of the developmental landscape of the mobile information system domain. This study provides a good basis for analysing the evolution of research in mobile information systems and may serve as a potential foundation for future research.

As to different angles of attack and nonlinear problems caused by high temperatures in coexisting hypersonic aircraft, people mainly rely on fluid software for research but lack analysis of flow mechanisms. Owing to computational difficulties, few people use numerical algorithms to combine them for discussion. Hence, this study aims to make a deep inquiry into the laminar flow and heat transfer of compressible Newtonian fluid in hypersonic aircraft with small attack angles.

In this paper, on the basis of mass, momentum and energy conservation laws, the governing equations of the hypersonic boundary layer are established. Viscosity, specific heat capacity and thermal conductivity are considered nonlinear functions concerning temperature. In virtue of the MacCormack finite difference method, the stationary numerical solutions are solved directly, and the validity of the algorithm is verified.

The results demonstrate that at Mach number 5, compared to the 0° attack angle, the maximum temperature near-wall at the 3° attack angle increases by about 25%. An enjoyable phenomenon is discovered, where the position corresponding to the maximum wall shear force shifts back as the attack angle and Mach number increase. The relationship between the near-wall maximum temperature versus attack angle and Mach number is fitted through numerical calculation results.

Empirical formulas can be used to estimate heat transfer characteristics at small attack angles, which will guide the design of aircraft thermal protection systems.

This study, based on construal level theory, aims to examine the influential mechanism of leader empowerment behaviour on employee creativity. Specifically, it examines the mediating role of cognitive flexibility between leader empowerment behaviour and employee creativity, along with the moderating effect of consideration of future consequences (CFC) on this linkage.

A two time-point survey study (n = 214) was conducted to collect information from leaders and employees in terms of mutual evaluation in several Chinese industries. To effectively avoid common source bias, this survey was conducted through pairing leaders and employees. During the survey, the supervisors and subordinates were double-blinded. Correlation analysis and hierarchical regression analysis were used to test the research hypotheses.

Firstly, leader empowerment behaviour can significantly predict employee creativity. Second, cognitive flexibility plays a partial mediating role in the linkage between leader empowerment behaviour and employee creativity. Thirdly, CFC moderates the relationship between leadership empowerment behaviour and cognitive flexibility. The mediating role of cognitive flexibility underlies the overall moderating effect of CFC on the relationship between leader empowerment behaviour and employee creativity.

We used construal level theory to explain the influence of the mechanism of leader empowerment behaviour on employee creativity. In this manner, this study bridges the gap between theory and practice, as well as enriching the research on leader empowerment behaviour and employee creativity, especially in the Chinese context. Moreover, our study has several practical managerial implications, based on the importance of employee creativity. It inspires the implementation of leader empowerment behaviour, cultivation of employee creativity and introduction of several procedures.

This paper discusses the influential mechanism of leader empowerment behaviour on employee creativity from a new perspective and explains the process of encouraging employee creativity through information-processing methods. It mainly highlights the application of construal level theory to discuss employee creativity and develops a new research frame for employee creativity. Leaders can raise employee creativity through leader empowerment behaviour.

The former residences of historical figures are typical landscape elements of historic districts, which are characterised by the styles of these residences and spiritual historical figures cultures. The purpose of this paper is to determine how the former residences respond once the historical figures living there have passed.

The history of human culture and progression of urban construction – which are submerged in societal transformation – is recorded for old Beijing city. Narrative space theory is used and methods such as a content analysis, map overlay and the Geographic Information System are employed to analyse the selected 300 former residences of historical figures in old Beijing city.

The results are as follows: the political setting played a key role in the evolution process, three political narrative areas in the inner city and one cultural narrative area in the outer city form the narrative spatial structure of the former residences of historical figures, “government construction” and “resident construction” are the main reasons for the loss and destruction of narrative spaces and ordinary life is an important channel for showcasing the history of former residences. The narrative spaces of these residences carry double histories, namely, the development of human history and of city construction.

Different from former studies that focus on the preservation of the single historical building, this study explores the integral logic of historic buildings in the whole city through narrative space theory to get a combination of culture and space.