With the development of market economy and the enhancement of environmental awareness, market-based environmental regulation will play an increasingly important role. Based on the panel data of 300 prefecture-level cities in China from 2008 to 2022, taking carbon emission trading policies as a quasi-natural experiment, the multi-time-point differential method was adopted to empirically study the impact of market-based environmental regulations on regional green innovation. It is found that the carbon emission trading policy significantly promotes urban green innovation, and this conclusion remains valid in the robustness test. Mechanism analysis shows that talent gathering, public awareness of environmental protection and government investment in science and technology play an important role in promoting green innovation. In addition, there is regional heterogeneity in the policy effect, which has a more significant promoting effect on green innovation in East China, Central China and non-central cities. The research conclusions of this paper have important implications for the government to strengthen the construction of carbon trading market, increase personnel training, enhance public awareness of environmental protection, and strengthen regional collaborative management, so as to promote the construction of a green and low-carbon society and the realization of sustainable development goals.

The offshore RMB market is not only an important part of China’s great power, but also a long-term demand for China’s financial opening up and an objective need to promote the internationalization of RMB. However, with the acceleration of RMB internationalization, the development of the RMB offshore market faces obstacles such as the slowdown in domestic economic growth, the decline in the yield of RMB assets, the lack of liquidity in the offshore market, and the high external geopolitical risks. In view of the above problems, on the basis of a comprehensive review of the current situation of RMB internationalization, financial institutions was encouraged to innovate financial products, the share of RMB in trade settlement and the scale of reshoring with RMB treasury bonds as the carrier were expanded, and multilateral cooperation and dialogue mechanisms was strengthened, so as to provide suggestions and suggestions for the healthy development of the RMB offshore market.

Improving the ecological resilience of the Yellow River Basin is an important aspect of ecological protection and high-quality development.A spatial econometric model was used to analyze the impact of digital economy on ecological resilience in 66 cities in the Yellow River Basin from 2011 to 2020.The results indicate that the overall level of ecological resilience in the Yellow River Basin is relatively low, with slow development and further widening regional disparities. The role of digital economy in ecological resilience has obvious nonlinear characteristics, with a more significant impact on the entire watershed and upstream, while the impact on the midstream is less significant. The impact of the digital economy on ecological resilience has a significant spatial spillover effect, with direct and indirect benefits across the entire watershed. The direct effect is dominant in the middle and lower reaches, while the spatial spillover effect in the upstream is not significant. The main reasons for the non-linear effect of digital economy on ecological resilience are the differences in economic development, government intervention, and foreign investment.

With the rapid development of the digital economy, digital assets, as a new type of asset category, are showing an exponential growth trend. A comprehensive and systematic classification and summary of the types of digital assets was firstly conducted, and the valuation systems and operation mechanisms of various digital assets were deeply analyzed. The risks and challenges currently faced by the digital asset field were also examined and the regulatory measures at the regulatory level were discussed. Through in-depth and detailed sorting and analysis, scientific basis and guidance are provided for the future development of the digital asset field.

In the context of high-quality development, in response to the new requirements of improving the innovation system, can environmental regulation promote the simultaneous improvement of the quantity and quality of green innovation of enterprises? Based on the enterprise level, an index was constructed in this study to describe the intensity of environmental regulation, and the impact of environmental regulation on the quantity and quality of green innovation and the heterogeneous characteristics of environmental regulation through the mediating role of innovation investment was examined. The results show that environmental regulation can significantly promote the quantity of green innovation of enterprises, but the impact on the quality of innovation is not statistically significant, and the conclusion is still valid after the endogenous treatment and robustness test. Enterprise R&D investment and government subsidies play a partial and complete mediating role in the relationship between environmental regulation and the quantity and quality of green innovation of enterprises, respectively. The heterogeneity analysis shows that environmental regulation can affect the number of green innovation in the central region, foreign-funded enterprises and large enterprises. The impact on the quality of green innovation is more pronounced in state-owned enterprises and large enterprises.

To address the lack of emphasis on carbon emissions in traditional airline network and fleet planning, an integrated optimization approach that incorporates carbon emissions into the planning process was proposed. The model was based on a multi-allocation hub-and-spoke network structure, taking into account route selection, demand distribution, capacity constraints and fleet size. Emissions were calculated using Environmental Protection Agency (EPA) standards, cruise phases, and a carbon tax mechanism was applied to convert emissions into cost elements, resulting in a joint optimization mathematical model aimed at minimizing airline operating costs. The model was solved using the Gurobi commercial solver. Results indicate that airlines should prioritize low-emission short-haul flights to meet market demand, and policymakers should consider gradually raising carbon tax levels to foster sustainable development in the aviation industry.

Erosion wear of movable elbow is an important problem that cannot be ignored in fracturing field. In view of the phenomenon that particles carried in fracturing fluid are prone to erosion and wear of movable elbow pipes, a flow channel model was established. Orthogonal tests were designed according to the fluid parameters and pipeline structural parameters of movable elbow, and the influence of the erosion rate was analyzed by CFD numerical simulation. The test results show that the influence degree of each working parameter on the erosion rate of movable elbow is particle mass flow rate > particle diameter >2# bend Angle > flow rate. According to the orthogonal test results can guide the actual work, when the movable elbow is placed in U-shape, the erosion wear is the largest, and the position is in the bending surface of the elbow, so the movable elbow should be avoided in the U-shape state to reduce the erosion. At the same time, the erosion resistance design of the bend of the movable elbow is carried out, and the triangle erosion resistance groove is added. The maximum erosion wear rate of the original structure and the improved structure is compared with that of the original structure. The erosion wear of the improved structure is reduced by 39.01%, which proves that the improvement can effectively reduce the erosion wear of the movable elbow during work, and provides a solution for the erosion resistance of the movable elbow.

In the context of smart city development, the intelligent transformation of communities, as a critical juncture for the interaction between urban information and residents’ daily lives, has become increasingly significant. Based on 251 relevant articles from the CNKI database spanning 2012 to 2024, bibliometric analysis was employed and CiteSpace6.3.R1 was used to visualize keyword co-occurrences, clustering and emerging trends, thereby the research hotspots and frontiers in smart community development was identified. The findings show that future advancements should focus on five key areas, such as information security, human-centered design, smart elderly care services, sustainability and resilience and equitable public service provision.

To study the optimal excavation method for shallow-buried soft rock large-section tunnels, detailed numerical models were established for the step method, the cross-middle wall method and the double side wall guiding pit method. The research focused on the time-space evolution of the ground displacement field during the construction process and the stress distribution of the supporting structure. The results show than the excavation using the double side wall guiding pit method induces smaller crown settlement displacements. The ground settlement caused by the three excavation methods is characterized by a U-shaped curve, with the double side wall guiding pit method resulting in the smallest surface settlement displacement. The initial support stress calculated for the double side wall guiding pit method is higher, but remains within a safe range.

Agricultural credit is an important driving force for the economic development of pastoral areas, and the lending behavior is also very common among the herdsmen. Some herdsmen even repay the loans by means of “borrowing the new and returning the old”. Therefore, it is of great significance to explore the heterogeneous impact of agricultural credit on the income increase of the herdsmen. Using the survey data of pastoral farmers covering the four cities of Inner Mongolia in 2020, the two stage of least squares (2 SLS) was used to test the heterogeneous effect of agricultural credit on animal husbandry. The results show that the promotion effect of agricultural credit on the net income of pastoral households is relatively significant, mainly acting on livestock income and non-livestock income. There is obvious heterogeneity in the income effect of agricultural credit in pastoral households with different micro characteristics. It is better income effect of pastoral credit with higher income level, higher income effect of pastoral credit with rich human capital, and higher income effect of credit in pastoral households with short feeding time is more effective. In the results of the mediation effect analysis, agricultural credit can affect the livestock size of pastoral households and thus affect their income. In view of the above results, suggestions are put forward for further improving the financial literacy of pastoral families in the future, vigorously playing the role of inclusive finance and commercial credit, and increasing the credit support of pastoral families.