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This paper aims to systematically study the effects of reflow temperature and SAC0307 (SAC) content on the micromorphology and mechanical properties of Sn58Bi-xSAC0307 composite solder joints to meet the requirements of high integration and low-temperature packaging of devices and provide references for the application of composite solder joints.

Sn58Bi and SAC0307 solder paste was mechanically mixed in different proportions to prepare Sn58Bi-xSAC0307/ENIG solder joints. The thermal properties, microstructure and mechanical properties of the composite solder joints were studied.

As SAC content in the solder increases, the balling temperature of SnBi-SAC solder gradually increases. The addition of SAC alloy reduces the grain size of large Bi-rich phase, and there are small-sized dispersed Bi and Ag3Sn particles in the bulk solder. The intermetallic compounds composition of the SnBi-xSAC/ENIG solder joint changes from Ni3Sn4 to (Ni, Cu)3Sn4 and (Cu, Ni)6Sn5 with SAC increasing. As the soldering temperature increases, the strength of all solder joints shows a rising trend. Among them, the shear strength of SnBi-20SAC solder joints at a reflow temperature of 150°C is approximately 37 MPa. As the reflow temperature increases to 250°C, the shear strength of solder joints increases to approximately 67 MPa.

This study provides a reference for the optimization of low-temperature solder composition and soldering process under different package designs.

In the era of the digital economy, higher demands are placed on versatile talents, and the cultivation of students with innovative and entrepreneurial abilities has become an important issue for the further development of higher education, thus leading to extensive and in-depth research by many scholars. The study summarizes the characteristics and patterns of dual-innovation education at different stages of development, hoping to provide a systematic model for the development of dual-innovation education in China and make up for the shortcomings.

This paper uses Citespace software to visualize and analyze the relevant literature in CNKI and Web of Science databases from a bibliometric perspective, focusing on quantitative analysis in terms of article trends, topic clustering, keyword co-linear networks and topic time evolution, etc., to summarize and sort out the development of innovation and entrepreneurship education research at home and abroad.

The study found that the external characteristics of the literature published in the field of bi-innovation education in China and abroad are slightly different, mainly in that foreign publishers are more closely connected and have formed a more stable ecosystem. In terms of research hotspots, China is still in a critical period of reforming its curriculum and teaching model, and research on the integration of specialization and creative education is in full swing, while foreign countries focus more on the cultivation of students' entrepreneurial awareness and the enhancement of individual effectiveness. In terms of cutting-edge analysis, the main research directions in China are “creative education”, “new engineering”, “integration of industry and education” and “rural revitalization”.

Innovation and entrepreneurship education in China is still in its infancy, and most of the studies lack an overall overview and comparison of foreign studies. Based on the econometric analysis of domestic and foreign literature, this paper proposes a path for domestic innovation and entrepreneurship education reform that can make China's future education reform more effective.

With the rise of digital construction, using organizational capabilities to improve project performance in a turbulent environment has become critical for the high-quality development of the construction industry. However, the complex relationships among them remain unclear. Therefore, this study explores these linear relationships under the digital construction mode and reveals the driving mechanism of multi-factor linkage on project performance.

Data were collected from 263 project participants in digital construction projects in China using a questionnaire. Hypothesis testing was conducted using partial least square structural equation modeling, and the differentiated patterns of project performance formation were revealed through fuzzy-set qualitative comparative analysis.

Organizational information technology, innovation, coordination, integration management and emergency management capabilities improve project performance. Environmental turbulence is a positive moderator between coordination capabilities and project performance, while other capabilities do not align with environmental turbulence. The research obtained five equivalent configurations for achieving high project performance, such as “capability layout” and “internal driven,” and two paths that lead to non-high project performance. Finally, in contrast to existing studies, we discovered the outstanding contribution of emergency management capabilities to project performance and the auxiliary effect of information technology capabilities.

This study innovatively integrates a dimensional framework of construction project organizations’ capabilities under a digital construction mode and extends the organizational capabilities to the specific and operational capability dimension level. Furthermore, this study opens the “black box” of the influence of organizational capabilities on project performance in environmental turbulence and reveals the differentiated and equivalent configurations for the formation of project performance. The study broadens the theoretical perspective of organizational capabilities on project performance research in the digital context and provides practical enlightenment for guiding the capability configuration of construction project organizations in a turbulent environment. The study broadens the theoretical perspective of organizational capabilities on project performance research in the digital context and provides practical enlightenment for guiding the capability configuration of construction project organizations in a turbulent environment.

This paper aims to investigate whether the establishment of commodity futures can effectively hedge systemic risk in the spot network, given the context of financialization in the commodity futures market.

Utilizing industry association data from the Chinese commodity market, the authors identify systemically important commodities based on their importance in the production process using multiple graph analysis methods. Then the authors analyze the effect of listing futures on the systemic risk in the spot market with the staggered difference-in-differences (DID) method.

The findings suggest that futures contracts help reduce systemic risks in the underlying spot network. Systemic risk for a commodity will decrease by approximately 5.7% with the introduction of each corresponding futures contract, since the hedging function of futures reduces the timing behavior of firms in the spot market. Establishing futures contracts for upstream commodities lowers systemic risks for downstream commodities. Energy commodities, such as crude oil and coal, have higher systemic importance, with the energy sector dominating systemic importance, while some chemical commodities also have considerable systemic importance. Meanwhile, the shortest transmission path for risk propagation is composed of the energy industry, chemical industry, agriculture/metal industry and final products.

The paper provides the following policy insights: (1) The role of futures contracts is still positive, and future contracts should be established upstream and at more systemically important nodes in the spot production chain. (2) More attention should be paid to the chemical industry chain, as some chemical commodities are systemically important but do not have corresponding futures contracts. (3) The risk source of the commodity spot market network is the energy industry, and therefore, energy-related commodities should continue to be closely monitored.