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This paper aims to investigate the influence of different post-annealing cooling conditions, i.e. furnace cooling (heat treatment (HT) 1 – slow cooling) and air cooling (HT 2 – fast cooling), on the microstructure and mechanical properties of selective laser melting (SLM) built austenitic 316L stainless steel (SS).

Three sets of 316L SS samples were fabricated using a machine standard scanning strategy. Each set consists of three tensile samples and a cubic sample for microstructural investigations. Two sets were subsequently subjected to annealing HT with different cooling conditions, i.e. HT 1 and HT 2, whereas one set was used in the as-built (AB) condition. The standard metallographic techniques of X-ray diffraction, scanning electron microscopy and electron back-scattered diffraction were used to investigate the microstructural variations induced by different cooling conditions. The resultant changes in mechanical properties were also investigated.

The phase change of SLM fabricated 316L was observed to be independent of the investigated cooling conditions and all samples consist of austenite phase only. Both HT 1 and HT 2 lead to dissolved characteristic melt pools of SLM. Noticeable increase in grain size of HT 1 and HT 2 samples was also observed. Compared with AB samples, the grain size of HT 1 and HT 2 was increased by 12.5% and 50%, respectively. A decreased hardness and strength, along with an increased ductility was also observed for HT 2 samples compared with HT 1 and AB samples.

From previous studies, it has been noticed that most investigations on HT of SLM fabricated 316L were mainly focused on the HT temperature or holding time. However, the post-HT cooling rate is also an equally important factor in deciding the microstructure and mechanical properties of heat-treated components. Therefore, this paper investigates the influence of different post-annealing cooling conditions on microstructure and mechanical properties of SLM fabricated 316L components. This study provides a foundation for considering the post-HT cooling rate as an influential parameter that controls the properties of heat-treated SLM components.

The Fabry-Perot sapphire optical fiber sensor is an excellent choice for high-temperature sensing in civil and military fields, such as oil exploitation, engine and turbine. The purpose of this paper is to study the high-reflective film system withstanding high temperature in Fabry-Perot sapphire optical fiber high-temperature sensor. To improve the performance of the sensor and reduce the difficulty of signal acquisition, one of the key ways is to enhance the normalized light intensity of F-P sensor, which can be achieved by coating the high-reflective film system on the fiber end.

The high-reflective film system can be achieved by a multilayer film with alternating ZrO₂ and Al₂O₃ film layers whose refractive indexes are different. In addition, the optimum film alternating sequences and the influence of the number of film layers, incident angle and temperature should be obtained by numerical analysis.

With the increase of the number of film layers, the reflectivity rises gradually and the change trend is more and more gentle. A minimum of the spectral reflectivity will occur at a certain incident angle depending on the design of the periodic multilayer system. Temperature affects the reflectivity of high-reflective film system. The normalized light intensity of the F-P sensor coated with high-reflective film system enhances greatly which is helpful to the signal demodulation. The temperature response of the F-P sensor is mainly determined by the characteristics of the F-P cavity.

Higher reflectivity, lower cost and easy signal acquisition are the most important features of the introduced high-reflective film system for the Fabry-Perot sapphire optical fiber high-temperature sensor.

This paper aims to study the electrochemical corrosion performance of ultrafine-grained (UFG) Cu bulk in 0.5 M NaCl solution.

UFG Cu bulk were prepared by impacting at −196°C and following heat treatment. The electrochemical corrosion behaviors of coarse-grained (CG), impacted and subsequently annealed at 190°C Cu bulks were studied.

All the bulks displayed typical active-passive-transpassive behaviors (dual passive films without stable passive regions). The resistance to corrosion of impacted Cu bulk was notably superior to that of CG Cu bulk, and subsequently annealing further improved its corrosion resistance.

Except for mechanical properties, corrosion performance has been considered to be one of the most important aspects in bulk UFG metallic materials research for the prospective engineering applications.

Cryogenic impacting could effectively reduce grain size of CG Cu bulk to UFG scale and induce high density dislocation. Subsequent annealing resulted in a further decrease of grain size even to nanoscale, as well as nanometer twins. The grain refinement, high density dislocation and annealing twins effectively enhance the passivation capability, resulting in an increase in the corrosion resistance.

Using protest event analysis, this study aims to investigate which risk factors influence the severity of environmental protests in China, thus filling a gap in China-related environmental protest literature.

Using a database derived from media coverage of 129 environmental protests in China from 2009 to 2015, this empirical study identifies underlying risk factors influencing environmental protest severity, quantifies these protest cases and verifies the associations between risk factors and severity using ordered logistic regression.

The results show that higher environmental health threat, economic loss, distrust of local government, lack of local governmental response, improper local government action and higher population density are likely to increase environmental protest severity; however, contrary to expectations, environmental information disclosure has no significant effect. These findings illuminate the vital and variational role of local government throughout all stages of the evolutionary process in environmental protests. Moreover, public distrust of local government is the principal cause of these protests.

This study enhances the understanding of how Chinese environmental protests arise from the identified risk factors and contributes to quantitative multi-case research in this area. Furthermore, the findings may help local governments in China, as well as in other countries, to enact positive measures to prevent serious environmental protests and improve their ability to address the environmental problems that cause protests. More effective governance can decrease the number and severity of environmental protests and thus promote social stability.

Constructing a low-carbon agriculture (LCA) park is considered an effective means to reduce greenhouse gas (GHG) emissions in developing countries. This study aims to explore the effectiveness of integrated low-carbon agricultural technologies based on evidence from a pilot LCA experiment in Shanghai, China, from 2008 to 2011.

Integrated low-carbon technologies in an agricultural park were adopted to reduce GHG emissions. Reduced emissions and net economic benefits were calculated by comparing emissions before and after the implementation of the experiment.

Results show that the low-carbon agricultural park experiment markedly reduced GHG emissions. This outcome can be attributed to the integrated technologies adopted in the experiment, including the reuse and recycle of resources, control of environmental pollution and GHG emissions and improvement of economic efficiency and social benefit. All the technologies adopted are already available and mature, thus indicating the great potential of LCA to reduce GHG emissions despite the lack of advanced technologies. However, supporting policies may be necessary to motivate private interests in LCA because of the considerable starting investments.

Previous macro-level and policy studies on LCA are based on knowledge from experimental studies, which typically specify environmental conditions to explore solely the effects of one low-carbon technology. Practically, integrating several low-carbon technologies in one experiment may be more effective, particularly for extensive agriculture, in developing countries. The effectiveness of integrated technologies is insufficiently discussed in the literature. Therefore, this study explores how effective integrated feasible LCA technologies can be in terms of both emission reduction and economic benefits based on the data obtained from an experiment in Shanghai, China.

The purpose of this paper is to find out the anti‐smoking counselling frequency and its correlates in a sample of Chinese physicians.

In this paper, 268 physicians in Baoding, a city near Beijing, filled out a questionnaire asking about their own smoking status, their anti‐smoking behaviors as well as their opinions on how to reduce cigarette smoking in China.

The paper finds that 54 percent of the male and 8.4 percent of the female physicians were current cigarette smokers. When asked whether they had counselled their patients about cigarette smoking in the past year, 43.7 percent answered “always”; 38.1 percent “often”; 13.1 percent “sometimes”; 2.6 percent “occasionally”, and 2.6 percent said: “not much”. However, only 9.0 percent said that they were “very successful”. Physicians' anti‐smoking counselling practices were highly correlated with their own smoking status; whether they perceived their past anti‐smoking activities as successful; whether they thought that they should set examples by not smoking; whether they felt that they had the responsibility to help patients and whether they perceived themselves as influential in persuading patients to quit smoking.

The paper shows that messages aimed at increasing Chinese physicians' anti‐smoking counselling should appeal to their responsibility, exemplary role, and unique influence on patients' health‐related behaviors.

The paper adds to the few studies on Chinese physicians' cigarette smoking behavior and their anti‐smoking activities. In a country where cigarette smoking is a way of life among males, and few people are aware of the health consequences of cigarette smoking, physicians' efforts can be a spearhead to a cessation campaign.

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.

Environmental performance becomes a key issue for the sustainable development. Recently, incremental information technology is adopted to collect environmental data and improve environmental performance. Previous environmental efficiency measures mainly focus on individual decision-making units (DMUs). Benefited from the information technology, this paper develops a new environmental efficiency measure to explore the implicit alliances among DMUs and applies it to Xiangjiang River.

This study formulates a new data envelopment analysis (DEA) environmental cross-efficiency measure that considers DMUs' alliances. Each DMUs' alliance is formulated by the DMUs who are supervised by the same manager. In cross-efficiency evaluation context, this paper adopts DMUs' alliances rather than individual DMUs to derive the environmental cross-efficiency measure considering undesirable outputs. Furthermore, the Tobit regression is conducted to analyze the influence of exogenous factors about the environmental cross-efficiency.

The findings show that (1) Chenzhou performs the best while Xiangtan performed the worst along Xiangjiang River. (2) The environmental efficiency of cities in Xiangjiang River is generally low. Increasing public budgetary expenditure can improve environmental efficiency of cities. (3) The larger the alliance size, the higher environmental efficiency. (4) The income level is negatively correlated with environmental efficiency, indicating that the economy is at the expense of the environment in Xiangjiang River.

This paper contributes to developing a new environmental DEA cross-efficiency measure considering DMUs' alliance, and combining DEA cross-efficiency and Tobit regression in environmental performance measurement of Xiangjiang River. This paper examines the exogenous factors that have influences on environmental efficiency of Xiangjiang River and derive policy implications to improve the sustainable operation.

The stability maintenance system has played an essential role in maintaining social stability although it also has brought about social problems worthy of attention. Admittedly compensation-based stability maintenance policy can address the appeals of citizens whose rights are infringed and the dissolving effect in the provision of compensation can save the cost of stability maintenance but such stability maintenance system lacks equilibrium.

The establishment of a strict assessment system for stability maintenance performance can encourage the stability maintenance authorities to eliminate the “fuse effect” as much as possible and ensure the effective implementation of the stability maintenance system. However, the rigorous stability maintenance performance assessment also provides the possibility for profit-driven petitions.

Due to the continuous accumulation of social dissatisfaction and the lack of stability maintenance equilibrium in the implementation of the compensation-based stability maintenance policy, public governance will fall into a stability maintenance paradox of “greater instability resulting from stability maintenance”.

The provision of sufficient means for the people to protect their interest by implementing measures such as strengthening the rule of law mechanisms is the key to achieve long-term social stability.

The purpose of this paper is to investigate the role of transnational entrepreneurs in growing born global firms, with a focus on the growth process facilitated by collaborative entry mode.

The author chose the solar photovoltaic industry as the empirical setting. This industry is a particularly good context for the study because many firms in this industry sell knowledge-intensive products internationally from their inception. The primary data consist of 32 in-depth interviews with entrepreneurs, industry association representatives, research institute scholars, and professional service firms.

The study highlights the importance of transnational entrepreneurs who develop born global firms to maturity by using their technological knowledge, international connections, and bicultural advantages to navigate and leverage institutional complexity. Collaborative entry mode with distributors enables born global firms’ high growth rapidly, whereas transnational entrepreneurs play a central role in building and expanding international network. Initial public offering in overseas stock exchange accelerates the high growth trajectory of born global firm by signalling its maturity.

The author took a process perspective by examining the growth and maturity of born global firms by collaborative partnership; the author’s focus on the role of transnational entrepreneurs highlighted entrepreneurs’ sensitivity to institutional complexity along the growth trajectory.

The author recommends both incumbent and entrepreneurial firms in developed economies collaborate with transnational entrepreneurs in various business areas. Industry firms may be able to cooperate on product and marketing development, and professional service firms can offer services to expand born global firms further, because transnational entrepreneurs follow the global “rules of the game”.

The author shed important light on the role of transnational entrepreneurs throughout the growth of born global firms via collaborative entry mode. Furthermore, the author develops a multilevel framework for analysing the combined influence of transnational entrepreneur and institutional complexity on the growth of born global firm.