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Copper-graphite (Cu/C) is a type of seal material that has been widely used in liquid rocket engines and with normal metal pairs, has a high wear rate under liquid oxygen lubrication. In this study, bearing steel disks were subjected to a high-temperature oxidization and phosphating progress to create an oxidized tricresyl phosphating film (OTCP) film, using tricresyl phosphate (TCP) as the phosphating solvent. It is hoped that the surface wear rate and friction coefficient can be reduced by this method.

This study aim to form an anti-wear film on the surface of bearing steel, which can significantly improve the lubrication performance of Cu/C and bearing steel. The surfaces of bearing steel disks were dried to remove surface water and then put on a heating plate with a magnetic stirrer and a blue glazed oxide film obtained by heating the disks in the air at 200°C for 1 h. To create the OTCP film, bearing steel disks with a blue glazed oxide film were cleaned ultrasonically three times in ethanol and then placed in baths of TCP. After heating for 2 h at 120°C, excess TCP liquid was removed from the disks using ethanol, leaving an OTCP film on the disk surface.

It was found that steel coated with an OTCP film demonstrated better tribological performance (lower coefficient of fiction and wear rate) when pairing with Cu/C than either oxidized or untreated bearing steel. Additional chemical reactions occur when the oxide disk is immersed in TCP and the FePO₄ film is formed after heating. Additionally, the OTCP film coated steel displayed good corrosion resistance, as confirmed by electrochemical corrosion tests. This finding demonstrates the potential for this process in the aerospace industry.

The preparation of OTCP films via high-temperature oxidization and phosphating of bearing steel was demonstrated, with the tribological properties of the OTCP film being investigated alongside those of the original surface and an oxidized film surface. The fabrication of OTCP films is easily scaled up and exhibits significant advantages as a new technology for applications in mechanical contact seal lubrication.

The advances and continuous development of technology have been identified as significant influences on the accounting profession (AICPA, 1998). In the last twenty years, both academia and the accounting profession have been giving much attention to the demand and opportunity for audits to be performed automatically, continuously and in nearly real time. This paper presents a comprehensive review of continuous auditing research by providing an overview of the emergence and growth of the continuous auditing literature and classifying the extant continuous auditing research on the basis of four research characteristics indicated by a newly developed research taxonomy.

Bat algorithm (BA) is a global optimization method, but has a worse performance on engineering optimization problems. The purpose of this study is to propose a novel chaotic bat algorithm based on catfish effect (CE-CBA), which can effectively deal with optimization problems in real-world applications.

Incorporating chaos strategy and catfish effect, the proposed algorithm can not only enhance the ability for local search but also improve the ability to escape from local optima traps. On the one hand, the performance of CE-CBA has been evaluated by a set of numerical experiment based on classical benchmark functions. On the other hand, five benchmark engineering design problems have been also used to test CE-CBA.

The statistical results of the numerical experiment show the significant improvement of CE-CBA compared with the standard algorithms and improved bat algorithms. Moreover, the feasibility and effectiveness of CE-CBA in solving engineering optimization problems are demonstrated.

This paper proposed a novel BA with two improvement strategies including chaos strategy and catfish effect for the first time. Meanwhile, the proposed algorithm can be used to solve many real-world engineering optimization problems with several decision variables and constraints.

The purpose of this paper is to examine the relationship between the purchase of insurance and economic growth among agricultural households.

Using survey data of the agricultural sector obtained from China over two years, the authors highlight the effect of job switching between farm and non-farm activities on the demand for insurance by applying the difference-in-differences and triple differences methodologies.

The results show that compared with farm income, non-farm income is associated with an increased (decreased) demand for insurance among households in Eastern (Western) China. The inequality in degree of economic development between the regions plays an important role in this finding. Both education and income exhibit a positive relationship with insurance demand for most regions. In addition, in 2007, regardless of farm or non-farm sector, switches are (except in the northeast region) associated with a significant increase in insurance expenditures. Households who switched from the farm to non-farm sector in 2007 are significantly negatively associated with insurance expenditures in the western region.

Inequalities in the degree of economic development play an important role in insurance consumption.

The authors assess the determinants of insurance market development in the agricultural sector in China, characterized by inter-regional disparities in economic development.

This information will be useful in the selection of materials and technology for the detection and removal of mercury ions at a low cost and with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity.

Different nano- and bio-materials allowed for the development of a variety of biosensors – colorimetric, chemiluminescent, electrochemical, whole-cell and aptasensors – are described. The materials used for their development also make it possible to use them in removing heavy metals, which are toxic contaminants, from environmental water samples.

This review focuses on different technologies, tools and materials for mercury (heavy metals) detection and remediation to environmental samples.

This review gives up-to-date and systemic information on modern nanotechnology methods for heavy metal detection. Different recognition molecules and nanomaterials have been discussed for remediation to water samples. The present review may provide valuable information to researchers regarding novel mercury ions detection sensors and encourage them for further research/development.

Purpose: The study aims to explore the wider acceptance of blockchain technology and growing faith in this technology among all business domains to mitigate the chances of fraud in various sectors.

Design/Methodology/Approach: The authors focus on studies conducted during 2015–2022 using keywords such as blockchain, fraud detection and financial domain for Systematic Literature Review (SLR). The SLR approach entails two databases, namely, Scopus and IEEE Xplore, to seek relevant articles covering the effectiveness of blockchain technology in controlling financial fraud.

Findings: The findings of the research explored different types of business domains using blockchains in detecting fraud. They examined their effectiveness in other sectors such as insurance, banks, online transactions, real estate, credit card usage, etc.

Practical Implications: The results of this research highlight (1) the real-life applications of blockchain technology to secure the gateway for online transactions; (2) people from diverse backgrounds with different business objectives can strongly rely on blockchains to prevent fraud.

Originality/Value: The SLR conducted in this study assists in the identification of future avenues with practical implications, making researchers aware of the work so far carried out for checking the effectiveness of blockchain; however, it does not ignore the possibility of zero to less effectiveness in some businesses which is yet to be explored.

This work empirically evaluates the effectiveness of the novel ontology-based access-control mechanism and the common password-protected access-control mechanism for social blogs. The paper aims to discuss these issues.

The ontology-based access-control scheme is designed to fit two characteristics of blog activities: social relationships and tags. A laboratory experiment is conducted to assess the perceived privacy benefit and perceived ease of use of the two mechanisms.

Analytical results indicate that, with the ontology-based access-control scheme, users perceive more privacy benefit than with the password-protected access-control scheme. The perceived ease of use with the ontology-based and password-protected access-control systems did not differ significantly.

Cross-boundary collaborations need an appropriate approach to control communication access. Further study is required to evaluate the ontology-based access-control scheme applied in cross-organizational and cross-departmental collaborations.

From a knowledge management perspective, blogs can store personal and organizational knowledge and experiences. The ontology-based access-control scheme encourages knowledge sharing for appropriate persons.

The new ontology-based access-control mechanism can help online users keep secrets from selected people to gain more privacy benefits than the existing password-protected access-control mechanism.

Check-in based advertising is growing dramatically as the popularity of social media increases. The purpose of this paper is to explore which social cues are appropriate for check-in based advertising in social media based on media richness theory and how content effectiveness affects content generation intention based on achievement motivation theory.

A laboratory experiment was performed to evaluate the effects of social cue strategies on content effectiveness of attitude toward the ad and self-efficacy on recall. The influence of effectiveness on content generation intention are also measured in the experiment.

The results of a laboratory experiment indicated that a strategy of using plentiful social cues has high effectiveness as measured by the concept of attitude toward the ad. Content effectiveness measured by attitude toward the ad and self-efficacy on recall can directly affect user intentions to generating check-in based advertisements.

Although check-in based advertising is driven by the customers themselves rather than by the company, companies can encourage their customers to follow an appropriate check-in content generation strategy to improve effectiveness.

The findings of this study provide useful information for designing the content of social media designed to facilitate the promotion of products and companies in online marketing.

In theoretical contribution, this study integrates media richness theory and achievement motivation theory to explore how users intent to generate check-in advertising according to social cues effectiveness.

Although research on foreign market entry and expansion behavior has attracted significant interest in the literature, there is a general lack of research (either conceptual or empirical) on the exit behavior of international companies. To address this issue, the authors develop a conceptual framework to understand firms’ foreign exit behavior. The objective is to lay the conceptual foundation for subsequent empirical research in this area. A series of research propositions have been advanced that can guide hypothesis generation for future research.

The application of digital twins to optimise operations and supply chain management functions is a bourgeoning practice. Scholars have attempted to keep pace with this development initiating a fast-evolving research agenda. The purpose of this paper is to take stock of the emerging research stream identifying trends and capture the value potential of digital twins to the field of operations and supply chain management.

In this work we employ a bibliometric literature review supported by bibliographic coupling and keyword co-occurrence network analysis to examine current trends in the research field regarding the value-added potential of digital twin in operations and supply chain management.

The main findings of this work are the identification of four value clusters and one enabler cluster. Value clusters are comprised of articles that describe how the application of digital twin can enhance supply chain activities at the level of business processes as well as the level of supply chain capabilities. Value clusters of production flow management and product development operate at the business processes level and are maturing communities. The supply chain resilience and risk management value cluster operates at the capability level, it is just emerging, and is positioned at the periphery of the main network.

This is the first study that attempts to conceptualise digital twin as a dynamic capability and employs bibliometric and network analysis on the research stream of digital twin in operations and supply chain management to capture evolutionary trends, literature communities and value-creation dynamics in a digital-twin-enabled supply chain.