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Gallic acid is a substance that is widely found in nature. Initially, it was only used as a corrosion inhibitor to retard the rate of corrosion of metals. In recent years, with intensive research by scholars, the modification of coatings containing gallic acid has become a hot topic in the field of metal protection. This study aims to summarize the various preparation methods of gallic acid and its research progress in corrosion inhibitors and coatings, as well as related studies using quantum chemical methods to assess the predicted corrosion inhibition effects and to systematically describe the prospects and current status of gallic acid applications in the field of metal corrosion inhibition and protection.

First, the various methods of preparation of gallic acid in industry are understood. Second, the corrosion inhibition principles and research progress of gallic acid as a metal corrosion inhibitor are presented. Then, the corrosion inhibition principles and research progress of gallic acid involved in the synthesis and modification of various rust conversion coatings, nano-coatings and organic resin coatings are described. After that, studies related to the evaluation and prediction of gallic acid corrosion inhibition on metals by quantum chemical methods are presented. Finally, new research ideas on gallic acid in the field of corrosion inhibition and protection of metals are summarized.

Gallic acid can be used as a corrosion inhibitor or coating in metal protection.

There is a lack of research on the synergistic improvement of gallic acid and other substances.

The specific application of gallic acid in the field of metal protection was summarized, and the future research focus was put forward.

To the best of the authors’ knowledge, this paper systematically expounds on the research progress of gallic acid in the field of metal protection for the first time and provides new ideas and directions for future research.

The purpose of this paper is to study the aerodynamic characteristics of Ahmed body in longitudinal and lateral platoons under crosswind by computational fluid dynamics simulation. It helps to improve the aerodynamic characteristics of vehicles by providing theoretical basis and engineering direction for the development and progress of intelligent transportation.

A two-car platoon model is used to compare with the experiment to prove the accuracy of the simulation method. The simplified Ahmed body model and the Reynolds Averaged N-S equation method are used to study the aerodynamic characteristics of vehicles at different distances under cross-winds.

When the longitudinal distance x/L = 0.25, the drag coefficients of the middle and trailing cars at β = 30° are improved by about 272% and 160% compared with β = 10°. The side force coefficients of the middle and trailing cars are increased by 50% and 62%. When the lateral distance y/W = 0.25, the side force coefficients of left and middle cars at β = 30° are reduced by 38% and 37.5% compared with β = 10°. However, the side force coefficient of the right car are increased by about 84.3%.

Most of the researches focus on the overtaking process, and there are few researches on the neat lateral platoon. The innovation of this paper is that in addition to studying the aerodynamic characteristics of longitudinal driving, the aerodynamic characteristics of neat lateral driving are also studied, and crosswind conditions are added. The authors hope to contribute to the development of intelligent transportation.

Studies on developed economies showed that imposing taxes on animal-based foods could effectively reduce agricultural greenhouse gas emissions (AGHGEs), while this taxation may not be appropriate in developing countries due to the complex nutritional status across income classes. Hence, this study aims to explore optimal tax rate levels considering both emission reduction and nutrient intake, and examine the heterogenous effects of taxation across various income classes in urban and rural China.

The authors estimated the Quadratic Almost Ideal Demand System model to calculate the price elasticities for eight food groups, and performed three simulations to explore the relative optimal tax regions via the relationships between effective animal protein intake loss and AGHGE reduction by taxes.

The results showed that the optimal tax rate bands can be found, depending on the reference levels of animal protein intake. Designing taxes on beef, mutton and pork could be a preliminary option for reducing AGHGEs in China, but subsidy policy should be designed for low-income populations at the same time. Generally, urban residents have more potential to reduce AGHGEs than rural residents, and higher income classes reduce more AGHGEs than lower income classes.

This study fills the gap in the literature by developing the methods to design taxes on animal-based foods from the perspectives of both nutrient intake and emission reduction. This methodology can also be applied to analyze food taxes and GHGE issues in other developing countries.

This study aims to examine the differences in the impact of three leadership styles (transactional, transformational and creative) on intraorganizational online knowledge-sharing and employee creativity. Specifically, we use self-determination theory (SDT) to examine the impact of these three leadership styles on four aspects of online knowledge sharing (knowledge donating, knowledge collecting, lurking and active lurking) and the moderating role of organizational innovation on these relationships.

Data were collected from 361 employees of business-to-business organizations in Vietnam to support all our hypotheses. Structural equation modelling was used for data analysis.

Transformational, transactional and creative leadership were found to affect online knowledge sharing, wherein creative leadership had the most potent effect. Online knowledge sharing was found to mediate the impact of three types of leadership on employee creativity. The results also showed that organizational innovation moderates the influence of leadership on online knowledge sharing.

This paper extends the current knowledge management research on online knowledge sharing by studying two new behaviors (lurking and active lurking), linking diverse leadership styles to these behaviors and employee creativity, and exploring the moderating role of organizational innovation. Our findings shed light on the complexity of the relationship between leadership and online knowledge sharing. This study also provides valuable implications for practitioners to help them choose the most appropriate leadership style for their digitalization process to ensure optimal outcomes.

Based on the weak seismic performance and low ductility of coupled shear walls, engineered cementitious composites (ECC) is utilized to strengthen it to solve the deformation problem in tall buildings more effectively and study its mechanical properties more deeply.

The properties of reinforced concrete coupled shear wall (RCCSW) and reinforced ECC coupled shear wall (RECSW) have been studied by numerical simulation, which is in good agreement with the experimental results. The reliability of the finite element model is verified. On this basis, a detailed parameter study is carried out, including the strength and reinforcement ratio of longitudinal rebar, the placement height of ECC in the wall limb and the position of ECC connecting beams. The study indexes include failure mode and the skeleton curve.

The results suggest that the bearing capacity of RECSW is significantly affected by the ratio of longitudinal rebar. When the ratio of longitudinal rebar increases from 0.47% to 3.35%, the bearing capacity of RECSW increases from 250 kN to 303 kN, an increase of 21%. The strength of longitudinal rebar has little influence on the bearing capacity of RECSW. When the strength of the longitudinal rebar increases, the bearing capacity of RECSW increases little. The failure mode of RECSW can be improved by lowering the casting height of the ECC beam in a certain range.

In this paper, ECC is used to strengthen the coupled shear wall, and the accuracy of the finite element model is verified from the failure mode and skeleton curve. On this basis, the casting height of the ECC casting wall limb, the strength and reinforcement ratio of longitudinal rebar and the position of the ECC beam are studied in detail.

Sandwich structures with well-designed cellular cores exhibit superior shock resistance compared to monolithic structures of equal mass. This study aims to develop a comprehensive analytical model for predicting the dynamic response of cellular-core sandwich structures subjected to shock loading and investigate their application in protective design.

First, an analytical model of a clamped sandwich beam for over-span shock loading was developed. In this model, the incident shock-wave reflection was considered, the clamped face sheets were simplified using two single-degree-of-freedom (SDOF) systems, the core was idealized using the rigid-perfectly-plastic-locking (RPPL) model in the thickness direction and simplified as an SDOF system in the span direction. The model was then evaluated using existing analytical models before being employed to design the sandwich-beam configurations for two typical engineering applications.

The model effectively predicted the dynamic response of sandwich panels, especially when the shock-loading pulse shape was considered. The optimal compressive cellular-core strength increased with increasing peak pressure and shock-loading impulse. Neglecting the core tensile strength could result in an overestimation of the optimal compressive cellular-core strength.

A new model was proposed and employed to optimally design clamped cellular-core sandwich-beam configurations subjected to shock loading.

Owing to the growing importance of frugal innovation to the development of firms in the developing and emerging countries, the purpose of this paper is to investigate the effect of inclusive leadership (IL) on frugal innovation through the mediating roles of tacit and explicit knowledge sharing (EK). It also explores the possible moderating role of competitive intensity (CI) in the relationship between knowledge sharing (KS) and frugal innovation.

This study collected data via a questionnaire survey of a sample of 325 participants from 112 manufacturing and service firms to validate the relationship between inclusive leadership, knowledge sharing behaviors, competitive intensity and frugal innovation. Structural equation modeling and regression are adopted to estimate the effects of inclusive leadership on frugal innovation through the mediating role of knowledge sharing and moderating role of competitive intensity.

Findings reveals the significant impacts of inclusive leadership on aspects of knowledge sharing and frugal innovation. Moreover, the influences of tacit and explicit knowledge sharing on frugal innovation capability are enhanced in the intensive competitive environments.

Future research should investigate the potential moderating role of perceived organizational support in the relationship between specific aspects of knowledge sharing behaviors and frugal innovation.

The paper provides a valuable understanding and novel approach for managers and directors of firms in developing and emerging countries to improve frugal innovation capability through inclusive leadership practices and promotion of knowledge sharing in organizations.

The paper is unique in its attempt to fill theoretical gaps on the relationship between inclusive leadership and frugal innovation, and advance the insights of how inclusive leadership directly and indirectly fosters frugal innovation via mediating roles of tacit and explicit knowledge sharing.

The purpose of this paper is to analyze the optimal competition or cooperation decision between technology service platforms and governments in the context of fierce competition within urban agglomerations.

Based on the cooperation and competition game model, this study builds a two-level model for government and technology service platforms considering three cases: perfect competition, platform cooperation and government-led cooperation.

By analyzing the optimal strategies of the government and a platform in three cases, the research shows that choosing appropriate cooperation in a competitive situation is beneficial to both the government and the platform. Government-led cooperation is conducive to increasing social welfare. From the perspective of the platforms, if they actively seek cooperation, they can obtain higher subsidies and profits. The more intense the competition is, the higher the profits and social welfare generated from the platforms' active cooperation.

The contribution of this study relates to the development of technology service platforms in urban agglomerations. As local governments and platforms continuously undertake decision-making processes, this study constructs quantitative models to analyze the advantages and disadvantages of competition and cooperation. It is worth noting that relying on government subsidies to maintain the sustainable development of technology service platforms is not a long-term solution. Government subsidies play a vital role in the initial development of technology service platforms. The analysis results are in line with Guo et al. (2016), Jung and Feng (2020) and Li (2021) conclusions. Furthermore, long-term government subsidies will make platforms dependent on these subsidies. These are the contributions to the scientific literature.

Instead of focusing on vertical relationships, this study emphasizes the horizontal cooperation and competition relationship between platforms and local governments in an urban agglomeration. Thus, the vertical effects of government subsidies on platforms can be investigated. Another innovation is the social welfare policy goal, which is an important index for the development of urban agglomerations.

Unlike other types of corporate disclosure, corporate political disclosure (CPD), which is the disclosure of corporate political contributions and the related governing policies and oversight mechanisms, does not provide completely new information to stakeholders. Some of the information disclosed in CPD is available from other public records (e.g. the Federal Election Committee website or OpenSecrets website). Given this unique feature of CPD, it is interesting to investigate the cost and benefit tradeoff for firms of altering their CPD practice in response to policy and political uncertainty.

This study employs recently developed indexes of aggregate economic policy uncertainty (EPU) and a novel dataset of CPD transparency to examine the impact of EPU on CPD transparency and how the proprietary cost of corporate political activities moderates this association. The sample consists of S&P 500 companies from the 2012 to 2019 period.

The authors document that firms mitigate the heightened information asymmetry associated with higher aggregate EPU by increasing CPD transparency. The positive association between EPU and CPD is less pronounced for firms that are more sensitive to EPU, for firms that more actively manage EPU through corporate political contributions or lobbying activities and for firms that are followed by more analysts. The authors also find that more transparent CPD helps to mitigate the information asymmetry caused by heightened EPU. This study’s results hold when the authors control for other types of voluntary corporate disclosure.

This study contributes to the emerging literature on the determinants of CPD transparency by identifying EPU's positive impact on CPD transparency. This study also provides empirical evidence that the proprietary costs arising from the controversial nature of corporate political activities dampen firms' incentives to provide transparent CPD in response to heightened EPU, and that information on corporate political activities gathered and processed by financial analysts seems to lower the marginal benefit to companies of publicizing CPD on their own website.