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The aim of the present paper was to investigate the inhibition performance of the OF and/or IM on L360 steel in CO₂/H₂S environments. The pipeline steel surface usually has been pre-treated before using in the oil/gas field, such as by passivation, blackening, and phosphiding. The effectiveness of inhibition can vary because there are many differences between the metal matrix and the treated film.

Imidazoline (IM) was synthesized by using oleic acid and diethylenetriamine, and its composition was verified using Fourier transform infrared spectroscopy. The oxide film (OF) covering a sample of L360 steel was characterized using X-ray diffraction, and its surface morphology was observed using scanning electron microscope. Electrochemical impedance spectroscopy measurements were conducted to study the inhibition performance of IM- and/or OF-covered L360 steel in the CO₂/H₂S environments.

The results show that IM and OF can prevent corrosion on L360 steel in CO₂/H₂S environments, and the synergistic inhibition effect of IM and OF was very evident. A possible model is proposed to explain the synergistic inhibition effect in the CO₂/H₂S environments of IM and OF on L360 steel.

Few reports have concerned the effect of the OF on the inhibitor’s performance, especially in CO₂/H₂S systems. The aim of the present study was to investigate the inhibition performance of the OF and/or IM on L360 steel in CO₂/H₂S environments. A model is proposed to explain the synergistic inhibition effect mechanism between IM and OF.

Evaluating mechanical properties of simply made samples by 3D printing technology at nanoscale provides a clear path to better understand larger-scale responses of complex natural rocks. Therefore, to realize the similarity between synthetically manufactured materials and natural geomaterials, this study focused on nanoscale mechanical characterization of a 3D printed object with only two constituent components (gypsum powder and infiltrant).

The study method includes nanoindentation technique combined with numerical simulation via discrete element method (DEM).

Four typical load-displacement curves were identified from nanoindentation of total test points indicating a typical elastic-plastic behavior of the 3D printed gypsum rock sample. Mechanical parameters such as Young’s modulus and hardness were calculated by energy-based methods and a positive correlation was observed. The infiltrant was found to considerably be responsible for the majority of the sample nano-mechanical behavior rather than the gypsum particles, thus expected to control macroscale properties. This was decided from deconvolution and clustering of elastic modulus data. Particle flow modeling in DEM was used to simulate the nanoindentation process in a porous media yielding rock-alike mechanical behavior.

The results show a matching load-displacement response between experimental and simulation results, which verified the credibility of simulation modeling for mechanical behavior of 3D printed gypsum rock at nanoscale. Finally, differential effective medium theory was used to upscale the nanoindentation results to the macroscale mechanical properties, which provided an insight into the geomechanical modeling at multiscale.

This study aims to realize the multipurpose use of inorganic materials in adsorption treatment of pigment wastewater and preparation of core-modified Color Index Pigment Red 57:1 (C.I. Pigment Red 57:1, PR 57:1).

In this paper, the inorganic materials (sepiolite and SiO₂·nH₂O) were used in both PR 57:1 production wastewater treatment and its core-modification. The inorganic material firstly adsorbed 3-hydroxy-2-naphthoic acid (bon acid) in the pigment wastewater to reduce chemical oxygen demand. Then, the inorganic material adsorbed with bon acid was reused to prepare core-modified PR 57:1.

In the pigment wastewater adsorption experiment, it was found that under pH = 3, the adsorption percentage of bon acid by inorganic material can reached up to 46.00%. The pigment characterization results showed that the core-modified PR 57:1 had a core-shell structure. Under UV light irradiation for 1 h, the core-modified PR 57:1 prepared with sepiolite and SiO₂·nH₂O showed total color difference ΔE value of 1.43 and 2.05, respectively, which was lower than that of unmodified PR 57:1 (ΔE = 2.89). In addition, the transmittance of pigment water suspension test results showed that the core-modified PR 57:1 showed better water dispersibility.

This paper attempts to develop a synergistic strategy based on the multipurpose use of inorganic materials in adsorption treatment of pigment wastewater and preparation of core-modified PR 57:1.

As a crucial element of city planning, an adequately planned logistics center for agricultural products can improve the circulation efficiency of agricultural products, thereby contributing to a convenient lifestyle of urban residents. First, this study analyzed the functional zones of urban green logistics centers for agricultural products based on low-carbon idea. A method was also proposed to calculate the area of each functional zone. Moreover, this study proposed a layout planning innovation method of urban green logistics centers for agricultural products based on logistics motion line analysis and logistics intensity calculation. Lastly, this study analyzed the application processes of the layout planning methodology according to the topographical conditions of Huai’an logistics center project case in China. Results of the case study show that the construction innovation method proposed in this study is scientific, reasonable, and practical. The construction innovation method can be also used for the planning and designing of similar urban logistics centers.

Autonomous flight of unmanned aerial vehicles (UAVs) in global position system (GPS)-denied environments has become an increasing research hotspot. This paper aims to realize the indoor fixed-point hovering control and autonomous flight for UAVs based on visual inertial simultaneous localization and mapping (SLAM) and sensor fusion algorithm based on extended Kalman filter.

The fundamental of the proposed method is using visual inertial SLAM to estimate the position information of the UAV and position-speed double-loop controller to control the UAV. The motion and observation models of the UAV and the fusion algorithm are given. Finally, experiments are performed to test the proposed algorithms.

A position-speed double-loop controller is proposed, by fusing the position information obtained by visual inertial SLAM with the data of airborne sensors. The experiment results of the indoor fixed-points hovering show that UAV flight control can be realized based on visual inertial SLAM in the absence of GPS.

A position-speed double-loop controller for UAV is designed and tested, which provides a more stable position estimation and enabled UAV to fly autonomously and hover in GPS-denied environment.

This paper describes the organic geochemical characteristics and their roles on barium enrichment in the No. 2 Coal from Huanglong Jurassic Coalfield, China. A total of 18 bench samples were taken from Huangling Mine 2. The average content of barium (3701 mg/kg) was about 23 times higher than that of common world coals. Terrestrial higher plants were the main coal-forming parent material. Relying on the parameters of OEP, Pr/Ph and so on, there is little correlation between organic geochemical characteristics and barium enrichment. Therefore, organic material has little influence on the process of coal-forming and the enrichment of barium.

Live streaming commerce, a new form of social commerce where firms integrate with broadcasters, community members and customers in live chat rooms for real-time interaction to help sell products, has become increasingly popular. However, factors that impact the success of live streaming commerce are not fully explored. The purpose of this study is to examine these factors by exploring the relationships among customer trust (i.e., trust in broadcasters, community members, and products) and customer engagement, and the mediating role of swift guanxi.

The authors surveyed 422 customers who have watched Taobao Live, one of the largest live streaming commerce sites in China, and used their questionnaires to test the research model employing partial least squares modeling.

The authors’ results indicate that trust in broadcasters has a positive effect on trust in products and community members, which positively influences trust in products. Additionally, swift guanxi has a fully mediating effect on the relationship between customers' trust in broadcasters and customer engagement.

First, from the theoretical perspective, this study comprehensively identifies three types of trust, explores the transfer relationships among trust in broadcasters, community members, and products based on Trust Transfer Theory. In addition, this study examines the mediating influence of swift guanxi on the relationship between customer trust and engagement. Second, from the managerial perspective, the study provides insights to help broadcasters and practitioners use live streaming to facilitate shopping.

This paper aims to reveal the green governance role played by stock connect in transition economies from the perspective of corporates’ environmental violations and provides implications for the coordination and optimization of subsequent stock market liberalization and green transformation policies in pursuit of carbon peaking and carbon neutrality goals.

With the data of Chinese listed enterprises, this paper takes the Shanghai-Hong Kong Stock Connect or Shenzhen-Hong Kong Stock Connect in China as a quasi-natural experiment and applies the multi-period difference-in-difference (DID) model to identify the impact of stock market liberalization on the corporates’ environmental violations.

The findings reveal that the stock market liberalization significantly restrains the corporates’ environmental violations. These findings are robust to a series of sensitivity tests, including excluding two-way effects, adjusting the year of policy implementation, replacing the core variables, introducing the regional fixed effects and excluding the interference effect of other relevant policies during the sample period. Furthermore, the stock market liberalization is beneficial for upgrading information disclosure quality, improving internal governance capability, strengthening environmental protection incentives, and thus restrains corporates’ environmental violations. Meanwhile, heterogeneity tests show that the inhibitory effects are more significant in those grouped samples which is large scale, state-owned nature, located in eastern region, with poor evaluation performances and heavy tax burden.

We make two marginal contributions to the current literature. First, this paper enriches the literature on the factors influencing corporate environmental violations by focusing on how the macro-level financial policy influences the micro-level corporate environmental violations. One the one hand, prior studies mainly focused on the consequences of corporate environmental violations; however, there is still a puzzle that the effect of stock market liberalization cannot be fully justified to influence corporate environmental violations. The findings help explain this puzzle by examining that stock market liberalization can restrain corporate environmental violations. Moreover, prior studies mainly focused on corporate share price (Yunsen Chen et al., 2022), market liquidity (Han Kim and Singal, 2000), information disclosure (Liang, Lin, and Chin 2012), corporate governance (Bae and Goyal, 2010) and corporate violations (Lingyun Xiong et al., 2021), but not on corporate environmental violations. We assume that the suppression effect of stock market liberalization on corporate environmental violations can help reduce corporate environmental violations, improve corporates’ awareness of environmental compliance. Second, this paper contributes to a better understanding of the literature on stock market liberalization by investigating the restraining effect of Stock Connect on corporate environmental violations from the perspective of information channel, corporate governance channel and motivation channel, which is of practical significance. Moreover, we investigate the differences in the inhibitory effects of stock market liberalization on different enterprises' environmental violations, from firm size, property rights, enterprise assessment results, tax burden to geographical location, which is conducive to the construction of a green financial system and the promotion of sustainable economic development. Our results show that firms which are large scale, state-owned nature, located in eastern region, with poor evaluation performances and heavy tax burden tend to compliance with environmental laws. These findings emphasize the importance and benefits of Stock Connect.

In recent years, China's marine industry has maintained rapid growth in general, and marine-related economic activities have continued to improve. The purpose of this research is to analyze the basic situation of China's marine economy development, identify the problems therein, forecast development trends and propose policy recommendations accordingly.

This research conducts a comprehensive and detailed analysis of the development of China's marine economy with rich data in diversified aspects. The current situation of China's marine economy development is analyzed from the perspective of scale and structure, and the external and internal development environment of China's marine economy is discussed. With the application of measurement and prediction method such as trend extrapolation, exponential smoothing, grey forecasting and neural network method, the future situation of China's marine economy development is forecasted.

In a complex environment where uncertainties at home and abroad have increased significantly, China's marine economy development suffers tremendous downward pressure in recent years. As China has achieved major achievements in the prevention and control of the COVID-19 epidemic, the marine economy development will gradually return to normal. It is estimated that the gross marine production value in 2022 will exceed 10 trillion yuan. China's marine economy will continue to maintain a steady growth trend in the future, and its development prospects will remain promising.

This research explores the current situation and trends of China's marine economy development and puts forward policy recommendations to promote the steady and health development of China's marine economy accordingly.

Drawing upon the social cognitive and customer engagement theories, the purpose of this paper is to investigate how individuals’ simple follow, purely aiming for information but with little contribution, could affect fans behavior and make them engage in company social network (CSN). The study identifies the impact of personal motivators (follower participation motivation), environmental antecedents (perception of information quality) and individual behavior (fan engagement behavior and stickiness) on CSNs and examines the interaction relationship between the follower participation motivation and perception of information quality.

Data collected from 392 valid questionnaires from WeChat Official Account users were analyzed by structural equation modeling.

Personal factor such as follower participation motivation (intrinsic and extrinsic motivator) was found to be significant predictor of fan engagement behavior. Environmental factor (perception of information quality: perceived usefulness as well as perceived entertainment) was a significant factor in determining followers’ proclivity to engage in CNSs. One significant interaction effect was found: the effect of perceived entertainment on fan engagement behavior was manifested to a greater extent when followers’ participation aimed for intrinsic motivator. The second interaction effect, between the extrinsic motivator and perceived usefulness, was also found to be statistically significant.

This study enriches and extends the studies on the theories of customer engagement and social cognitive theory. It applies the above theories to CSNs and advances CSNs research by taking into consideration both personal and environmental factors (follower participation motivation and perception of information quality), and the interaction effects of the two on individual behavior.