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The purpose of this paper is to prepare metallocene polyalphaolefin 8 (mPAO8) by the oligomerization of olefin from coal with metallocene catalyst system and compare it with commercially available polyalphaolefin 8 (PAO8) from Chevron.

Molecular structures, component and mass were determined by nuclear magnetic resonance spectroscopy, gas chromatography and gel permeation chromatography, respectively. The physico-chemical properties, including Noack volatility, viscosity index and elemental analyses, were studied. The oxidative stability was evaluated by pressurized differential scanning calorimetry, whereas the thermal stability was studied by thermo-gravimetric analysis.

The produced mPAO8 consisted of a large part of tetramer, pentamer and a small part of trimer and hexamer. Additive T501 significantly improved the oxidation stability of PAO8 from Chevron and the synthesized mPAO8. Both samples had similar properties, such as oxidative stability, additive response, pour point and Noack volatility loss. But mPAO8 possessed a higher thermal stability, better viscosity index and flash point than PAO8. Therefore, the mPAO8 prepared by the oligomerization of olefin from coal could be used as base oil for lubricant development.

The mPAO8 base oil was successfully prepared by successive carbon numbers and shows similar properties with commercially available PAO8 products from Chevron. The findings can cover the shortage of the synthesis lubricants market in China.

In an era marked by growing environmental concerns, businesses are increasingly recognizing the importance of Corporate Social Responsibility (CSR) in influencing customer behavior, particularly in the context of sustainability and green practices. This paper aims to examine the impact of Corporate Social Responsibility (CSR) on Customer Green Behavior (CGB) through the mediating role of corporate image, service quality, customer trust and customer satisfaction.

A convenient sampling technique was employed to collect the data sample. A total of 741 questionnaires were distributed across four different hotel sectors in China. By using Structural Equation Modeling, the results suggest that CSR significantly influences CGB. Moreover, corporate image, service quality, customer trust and customer satisfaction show a partial mediating effect in the relationship between CSR and CGB.

The study findings suggest that the hotel industry should invest in CSR initiatives to enhance CGB by conducting pro-environmental activities. This study emphasizes how important CSR initiatives are in encouraging customers to adopt eco-friendly behavior. Overall, the results of this study extend the understanding of CSR, CGB, corporate image, service quality, customer trust and customer satisfaction in the context of the hotel industry and offer theoretical and managerial implications for developing and developed economies.

The originality value of this research lies in its comprehensive examination of the mediating effects of corporate image, service quality, customer trust and customer satisfaction on the relationship between CSR and CGB in the hotel industry. Furthermore, the study’s focus on the specific context of China adds novel insights to the existing literature on CSR and CGB. Discussions, limitations and research suggestions for future study are also provided.

This paper aims to establish a systematic cognition to alleviate the supply–demand contradiction in rural financial markets from an integrated perspective of knowledge management and proposes the concept of rural financial knowledge ecosystem (RFKE) to encourage multifaceted solutions.

The authors qualitatively describe the process that the knowledge management dilemmas cause the supply–demand contradiction in the rural finance and further summarize a systematic methodology from three dimensions: the knowledge subject, the knowledge environment and the knowledge ecology.

The authors list four types of knowledge management dilemmas leading to the supply–demand contradiction in the rural finance, i.e. the weak knowledge sharing, the poor knowledge flow, the slow knowledge updating and the imperfect knowledge environment. Meanwhile, the RFKE model consisting of the ecological subject, the ecological environment and the ecological regulation is also presented.

The role of knowledge management in improving the allocation of financial resources to various rural financial market participants (government, rural financial institutions, farmers, agricultural enterprises, etc.).

The authors creatively give the RFKE model, which complements and enriches the theory of knowledge management. Meanwhile, relevant management practices are urgently needed under the macro circumstance of the COVID-19 pandemic and the rural revitalization in China.

The purpose of this paper is to investigate the effect of different soldering temperatures on the performance of chip-on-board (COB) light sources during vacuum reflow soldering.

First, the influence of the void ratio of the COB light source on the steady-state voltage, luminous flux, luminous efficiency and junction temperature has been explored at soldering temperatures of 250°C, 260°C, 270°C, 280°C and 290°C. The COB chip has also been tested for practical application and aging.

The results show that when the soldering temperature is 270°C, the void ratio of the soldering layer is only 5.1%, the junction temperature of the chip is only 76.52°C, and the luminous flux and luminous efficiency are the highest, and it has been observed that the luminous efficiency and average junction temperature of the chip are 107 lm/W and 72.3°C, respectively, which meets the requirements of street lights. After aging for 1,080 h, the light attenuation is 84.64% of the initial value, which indicates that it has higher reliability and longer life.

It can provide reference data for readers and people in this field and can be directly applied to practical engineering.

This paper aims to provide a framework of the supervised hyperspectral classification, to study the traditional flowchart of hyperspectral image (HIS) analysis and processing. HSI technology has been proposed for many years, and the applications of this technology were promoted by technical advancements.

First, the properties and current situation of hyperspectral technology are summarized. Then, this paper introduces a series of common classification approaches. In addition, a comparison of different classification approaches on real hyperspectral data is conducted. Finally, this survey presents a discussion on the classification results and points out the classification development tendency.

The core of this survey is to review of the state of the art of the classification for hyperspectral images, to study the performance and efficiency of certain implementation measures and to point out the challenges still exist.

The study categorized the supervised classification for hyperspectral images, demonstrated the comparisons among these methods and pointed out the challenges that still exist.

Multi-cycle Learning Study and multi-cycle Lesson Study are the main collaborative action research approaches for teacher professional development in Hong Kong. The sustaining of these Lesson Study innovations may be inhibited by many challenges. The purpose of this paper is to identify the strategies school leaders utilized to overcome challenges and sustain Lesson Study innovations successfully in a Hong Kong primary school.

In-depth case study was adopted as the methodological approach to explore how Lesson Study was implemented to improve teaching and learning in the school and what leadership practices were enacted to sustain Lesson Study in the case school.

It was found that the leadership team under study had adopted positive peer leadership to successfully implement Lesson Study activities. The strategies of positive peer leadership will be discussed in detail.

The paper concludes with implications for sustaining school development and professional development with Lesson Study and a checklist of positive peer leadership practices for school leaders, teacher leaders and teacher trainers.

This paper will enrich the understanding of successful leadership practices for sustaining Lesson Study innovations in schools, on which few empirical studies have been conducted.

The purposes of this study were to measure the relevance status of Index Islamicus, evaluate the semantic correlation between a query and documents and inquire the basis of its rank. Sorting the retrieved results from the most relevant to the least relevant is the common option of an information retrieval system. This sorting mechanism or relevance judgment is computed by measuring closeness of query with its documents.

Forming up 100 queries on Islamic History and Civilizations, with two indexing elements (keyword and concept), a laboratory experiment was generated on its first ten items of the rank. Throughout an experimental research design, the relevance status value formula was used to measure system-computed rank and compare it with mean average precision.

The results showed that the average status value of Index Islamicus’s ranking on relevance criterion was 18 per cent effective in terms of retrieving precise documents. Despite the main focus of this study being only on one subject domain and the items calculated were only 1,000, this small percentage of its ranking mechanism proved that semantic correlations between queries with subject domain did not achieve the satisfactory level.

Implication of this study could be a guideline for further research on ranking mechanism of other search engines because the limitation of this study was Index Islamicus being the only database, which was the focus of this study.

Throughout this study, Index Islamicus would be benefited knowing the status of its ranking mechanism as well as other databases can make further research on their own ranking method following this study.

Researchers and vendors of online databases can ensure their users a true platform of search engine with a proper ranking list.

Relevance status value model for Index Islamicus on Islamic History and Civilization that allows the system to rank documents according to the match between document and query and gives the idea of a better index. The model improves the system’s ranking mechanism, and promotes the use of semantic relationships. This research promotes the computation of relevance status value by domain for capturing subject-specific relevance criteria and semantic relationships.