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Polyethylene terephthalate (PET) as a fiber molding polymer is widely used in aerospace, electrical and electronic, clothing and other fields. The purpose of this study is to improve the thermal insulation performance of polyethylene terephthalate (PET), the SiO₂ aerogel/PET composites slices and fibers were prepared, and the effects of the SiO₂ aerogel on the morphology, structure, crystallization property and thermal conductivity of the SiO₂ aerogel/PET composites slices and their fibers were systematically investigated.

The mass ratio of purified terephthalic acid and ethylene glycol was selected as 1:1.5, which was premixed with Sb₂O₃ and the corresponding mass of SiO₂ aerogel, and SiO₂ aerogel/PET composites were prepared by direct esterification and in-situ polymerization. The SiO₂ aerogel/PET composite fibers were prepared by melt-spinning method.

The results showed that the SiO₂ aerogel was uniformly dispersed in the PET matrix. The thermal insulation coefficient of PET was significantly reduced by the addition of SiO₂ aerogel, and the thermal conductivity of the 1.0 Wt.% SiO₂ aerogel/PET composites was reduced by 75.74 mW/(m · K) compared to the pure PET. The thermal conductivity of the 0.8 Wt.% SiO₂ aerogel/PET composite fiber was reduced by 46.06% compared to the pure PET fiber. The crystallinity and flame-retardant coefficient of the SiO₂ aerogel/PET composite fibers showed an increasing trend with the addition of SiO₂ aerogel.

The SiO₂ aerogel/PET composite slices and their fibers have good thermal insulation properties and exhibit good potential for application in the field of thermal insulation, such as warm clothes. In today’s society where the energy crisis is becoming increasingly serious, improving the thermal insulation performance of PET to reduce energy loss will be of great significance to alleviate the energy crisis.

In this study, SiO₂ aerogel/PET composite slices and their fibers were prepared by an in situ polymerization process, which solved the problem of difficult dispersion of nanoparticles in the matrix and the thermal conductivity of PET significantly reduced.

Aiming at the high temperature, high speed, high precision and high surface quality of the copper belt cold rolling, the purpose of this paper is to develop a new type of lubricant for cold rolled copper belt.

The component of the developed oil was determined based on the physical and chemical properties of the base oil and the tribological properties, the oxidation resistance properties, the rust resistance properties, the anti-foam properties, the demulsibility and the other properties of the additives. The orthogonal experiment method was used to determine the optimum adding amount of the additives; finally, the developed oil formulation was determined.

The physical and chemical experiment results show that the developed oil has a good performance of oil film bearing capacity and oxidation resistance. The simulation of rolling experiment found that the developed oil can significantly reduce rolling pressure and effectively reduce the friction in the process of rolling.

The experimental results show that the developed oil has excellent performance and can meet the requirement of lubrication in the process of cold rolling copper belt.

In recent decades many emerging markets (EMFs) have undertaken entrepreneurial transformations to adapt to institutional transition and industrial change. Corporate entrepreneurship (CE) provided EMFs viable ways to revitalize, reconfigure, and transform successfully with the dynamic environment. Although previous research examined government roles on EMFs' CE activities, little is known about the mechanisms of how government exerts influence on CE activities. To fully understand CE of EMFs, we propose a stage model to explore specific roles governments play that affect CE activities over time. In particular, we investigate how governments' grabbing hand, helping hand, and invisible hand roles affected Chinese auto firms' CE activities at different stages from 1980 to 2016. Government involvement is summarized and the advantages and disadvantages of these roles are analyzed.

As a crucial institutional form established since the Chinese economic reform, the system of competitive local governments has been shaping the characteristics of China's socialist market economy to a considerable degree.

This study not only adopts the view of existing studies that attribute the economic motive of local governments to rent and consider land public finance as a means through which local governments carry out strategic investment but also attempts to further develop the view within a Marxist analytical framework.

As a result, the local governments have helped to maintain an incredibly high investment rate over a considerable period of time, facilitating the continuous, rapid growth of the Chinese economy.

This study concludes that China's local governments function as the productive allocator and user of rent in the strategic investment based on land public finance and thereby embed themselves in the relative surplus-value production initially arising from competition amongst enterprises, forming the dual structure of relative surplus-value production unique to China's economy.

The purpose of this paper is to analyze the historical development and characteristics of the globalizing Chinese automobile industry.

This study is positioned as an exploratory case study, using data triangulation techniques based on archival research and published reports of statistical agencies both at central government and single industry level.

China's automobile industry represents an extraordinary case of a development path toward globalization in a transitional economy. One of the obvious characteristics of the auto industry is that it necessitates technology transfer and innovative learning, which can be regarded as an important aspect of maintaining competitiveness in industrialization and global competition. The automobile industry in China is also characterized by state intervention and industrial regulations. The state initiated open-door reform has led to a mixed regulatory mechanism including both market-based competition and the legacy of a command economy. Other major features are demonstrated as follows: state-owned auto enterprises have been gradually given more freedom in the decision-making processes; the Chinese auto industry has shown phenomenal growth in the country's economic development with an average annual rate of about 9 percent. This achievement combined with the increasing impacts of globalization of production and market expansion has undoubtedly led to the increasing inflows of foreign direct investment in the form of international partnerships between the auto-producing MNCs and major local Chinese firms as per the industrial policies in the Chinese automobile industry.

This paper addresses an important topic, the historical development path of the Chinese automobile industry, but to date, it has received very little research attention. It advances the institution-based perspective and therefore develops a better understanding of changes in China's automobile industry over the past decades since 1949 and concludes that the combination of the influences of foreign technology, China's industrial policies and institutional dynamic processes has resulted in a unique dynamic development path for the globalizing Chinese automobile industry.

This study aims to improve the accuracy of hyperspectral estimation of soil organic matter content.

Based on the uncertainty in spectral estimation, 76 soil samples collected in Zhangqiu District, Jinan City, Shandong Province, were studied in this paper. First, the spectral transformation of the spectral data after denoising was carried out by means of 11 transformation methods such as reciprocal and square, and the estimation factor was selected according to the principle of maximum correlation. Secondly, the grey weighted distance was used to calculate the grey relational degree between the samples to be estimated and the known patterns, and the local linear regression estimation model of soil organic matter content was established by using the pattern samples closest to the samples to be identified. Thirdly, the models were optimized by gradually increasing the number of modeling samples and adjusting the decision coefficient, and a comprehensive index was constructed to determine the optimal predicted value. Finally, the determination coefficient and average relative error are used to evaluate the validity of the model.

The results show that the maximum correlation coefficient of the seven estimated factors selected is 0.82; the estimation results of 14 test samples are of high accuracy, among which the determination coefficient R² = 0.924, and the average relative error is 6.608%.

Studies have shown that it is feasible and effective to estimate the content of soil organic matter by using grey correlation local linear regression model.

The paper succeeds in realizing both the soil organic matter hyperspectral grey relation estimating pattern based on the grey relational theory and the estimating pattern by using the local linear regression.

Sharing and disseminating debunking information are critical to correcting rumours and controlling disease when dealing with public health crises. This study investigates the factors that influence social media users' debunking information sharing behaviour from the perspective of persuasion. The authors examined the effects of argument adequacy, emotional polarity, and debunker's identity on debunking information sharing behaviour and investigated the moderating effects of rumour content and target.

The model was tested using 150 COVID-19-related rumours and 2,349 original debunking posts on Sina Weibo.

First, debunking information that contains adequate arguments is more likely to be reposted only when the uncertainty of the rumour content is high. Second, using neutral sentiment as a reference, debunking information containing negative sentiment is shared more often regardless of whether the government is the rumour target, and information containing positive sentiment is more likely to be shared only when the rumour target is the government. Finally, debunking information published by government-type accounts is reposted more often and is enhanced when the rumour target is the government.

The study provides a systematic framework for analysing the behaviour of sharing debunking information among social media users. Specifically, it expands the understanding of the factors that influence debunking information sharing behaviour by examining the effects of persuasive cues on debunking information sharing behaviour and the heterogeneity of these effects across various rumour contexts.