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Daqing Gulong shale oil exhibits elevated wax content, a high wax precipitation point, and a high freezing point. However, its oil density and viscosity are relatively low, making it susceptible to wax crystal precipitation. The risk of pipeline clogging is heightened in lower ambient temperatures, posing a hazard to the safe production of shale oil. This study focuses on testing the fundamental physical properties of crude oil. The wax deposition flow loop was employed to replicate wax deposition in extracted fluids under actual high-flow gas-liquid conditions within a pipeline. The deposition patterns were determined based on the experimental findings. The results indicate that, irrespective of whether in single-phase, gas-liquid two-phase, or oil-gas-water three-phase conditions, the deposition mass rises with decreasing oil temperature. Furthermore, the deposition mass rises with an increased temperature difference between the oil and the pipeline wall. Conversely, the deposition mass declines with an increased gas-liquid ratio, and the deposition thickness declines with elevated water content. The observed deposition patterns highlight the significant influence of molecular diffusion and the impact of gas phase shear. These experimental findings offer valuable references and insights for the transportation of Daqing shale oil through pipelines.

This study attempts to shed new light on how the state as a minority shareholder benefits stakeholders, by investigating its role in deterring corporate fraud in non‐state‐owned enterprises (non‐SOEs). Through an analysis of publicly traded non‐SOEs in China, this study reveals that minority state ownership negatively impacts firm fraud, and the results hold after alternative tests. The identified channels of this association are that minority state ownership mitigates tunnelling, enhances internal control, and alleviates the financial constraints of non‐SOEs. Further analysis shows that this relationship is more pronounced in firms with weaker corporate governance, stronger fraud incentives, and lower levels of political connections. Overall, this study contributes to our understanding of the role of minority state ownership in emerging markets within the context of corporate fraud, highlighting the importance of critically evaluating the effects of government intervention in different contexts. [ABSTRACT FROM AUTHOR]

Partially encased concrete (PEC) has better mechanical properties as a structure where steel and concrete work together. Due to the increasing amount of construction waste, recycled aggregate concrete (RAC) is being considered by more people. However, although RAC has more points, the performance is inferior to natural aggregate concrete (NAC). To narrow or address this gap, lightweight, high-strength and corrosion-resistant CFRP can be used, also protecting the steel flange of the PEC structure. Therefore, carbon fiber reinforced polymer (CFRP) confined partially encased recycled coarse aggregate concrete columns were studied in this paper. With respect to different slenderness ratios, recycled coarse aggregate(RCA) replacement ratios, and number of CFRP layers, the performance of the proposed CFRP restrained columns are reported. The RCA replacement ratio is analyzed to be limited negative impact on the bearing capacity, generally within 6%. As for the slenderness ratio, the bearing capacity increased with it. However, wrapping CFRP significantly increased the bearing capacity. Considering the arch factor, a simple formula for calculating the ultimate strength of CFRP-confined partially encased RAC columns is developed based on EC4 and GB50017-2017. By comparison with the experimental values, the error is within 10%. [ABSTRACT FROM AUTHOR]

Research Question/Issue: We study whether tax enforcement can function as a corporate governance mechanism in emerging countries with weak tax enforcement. In the case of China, we examine whether and how external monitoring by tax authorities constrains insiders' opportunistic behavior in corporate mergers and acquisitions (M&As). Research Findings/Insights: We employ the implementation of the third stage of the China Tax Administration Information System (CTAIS‐3) as a quasi‐natural experiment and adopt a difference‐in‐differences (DID) approach. We find that strengthening tax enforcement by CTAIS‐3 can improve the efficiency of M&As by reducing agency problems in the decision‐making process. Our conclusions remain unchanged under a series of robustness checks. Moreover, the results show that the impact is mainly observed in regions with stronger local government taxation motivation and in firms with poorer internal or external governance and poorer accounting information. Theoretical/Academic Implications: We find that strengthening tax enforcement can improve M&A decisions even in emerging markets, which provides direct evidence for the predictions from theory that tax authorities play a governance role in supervising corporate insiders. Our paper also extends the literature on the determinants of M&A performance from the perspective of tax authorities. Practitioner/Policy Implications: This study has policy implications for governments around the world to improve corporate governance by strengthening tax enforcement. The Chinese government applying advanced information technology to tax enforcement can provide a reference for other countries. [ABSTRACT FROM AUTHOR]

The purposes are to solve the option pricing problem in financial derivatives and provide a practical basis for reducing the risk rate of the financial market. First, the classification of fractal theory and option pricing is outlined, the connotation of stochastic volatility is analyzed, and a stochastic volatility model is established. According to the Fourier transform and nonlinear differential equation, the pricing method in the volatility swap process and the pricing method of volatility derivatives are analyzed. Finally, the option pricing parameters are set, and the Origin 75 software is employed to visually analyze the mathematical results. The forward prices under stochastic volatility are compared monthly and weekly, and the resulted values are all close to 235. There is a gap between the forward prices of each month and each quarter, and the difference between the forward prices of each quarter is large, close to 50. The average relative percentage errors (ARPEs) within and out of the sample calculated by the stochastic volatility model are close to 16%, and the error gaps between different monetary intervals are also large. With the increase in strike price, the change rate of options under the random volatility model is faster than that of options under VIX index. When the strike price increases to 0.6, the two options are equal. The fitting trend of the stochastic volatility model for implied volatility at different maturity dates first decreases and then tends to a fixed value. The implied volatility of the 60-day-expiring option has changed significantly, showing a trend of increasing first and then tending to a fixed value (0.8). In contrast, the implied volatility of the 90-day-expiring option and the 120-day-expiring option almost have no change. When w (fractional operator) takes 1 and Y takes 1.6 and 1.3, the solution to the stochastic volatility model is consistent with that to the classic CGMY model. When w takes 1, the stochastic volatility model has the same solution as the classic CGMY and BS models. As the fractional order of time increases, the trend of asset price changes becomes smaller. [ABSTRACT FROM AUTHOR]

Revegetation programmes aim to avoid land degradation, control soil erosion, reduce floods, and improve ecological conditions. China has planted billions of trees over the past 20 years. However, little is known about the effectiveness of this artificial revegetation and its consequences on China's national conservation policies and changes in biophysical factors at the county level. Here we use satellite time series data and develop a new metric, the revegetation index (RVI), that quickly monitors revegetation and its long‐term changes. We found that the number of regions where the Grain to Green Program (GTGP) was successfully implemented was only about 55.8% of the areas of GTGP implementation. Surprisingly, we provide observational evidence that the implementation of the GTGP can decrease soil erosion and drought, and increase water availability, but revegetation in the Yangtze River basin (YRB) in China has a limited impact on soil erosion, water, and drought. In particular, for revegetation between 1999 and 2016, indicating that a previous assessment by the Government revealed as official statistics may have overestimated the effects of the ecological restoration practices. [ABSTRACT FROM AUTHOR]