Jie Li

Membrane technology demonstrates broad prospects in the field of methane capture and purification due to its high efficiency and low energy consumption characteristics. This paper systematically reviews the research progress in membrane technology for methane separation in recent years, focusing on the design and optimization of membrane material systems, in-depth analysis of mass transfer mechanisms, and practical applications in areas such as biogas upgrading and natural gas decarbonization. Researchers have significantly enhanced membrane separation performance for CO₂/CH₄, CH₄/N₂, and other systems by developing novel material systems such as polymer membranes, inorganic membranes, and mixed matrix membranes (MMMs), combined with strategies like pore structure regulation, interface optimization, and functionalization. Although membrane technology has shown good economic feasibility and application potential in some scenarios, challenges such as long-term material stability, anti-plasticization capability, and large-scale manufacturing remain the main current obstacles. Future research should further focus on the development of novel membrane materials, process integration optimization, and intelligent process control to promote a greater role for membrane technology in the efficient utilization of methane resources and energy structure transformation.

There are important ways to solve the ecological risk problems of regional water resources and soil resources, and to promote the benign development of soil and water resources, involving scientific evaluation of the ecological risk of soil and water resources in Hefei metropolitan area, clarifying the intrinsic evolution law of ecological risk and identifying the characteristics of spatial and temporal variations. Based on the conceptual model of “ST-QS-RR”, the evaluation indicator system is constructed, the CRITIC method is used to assign weights, and the TOPSIS method, kernel density method, markov chain and resistance model are used to measure and analyse the spatial and temporal characteristics of ecological risk of soil and water resources, and to explore the main factors that cause ecological risk of soil and water resources. The results of the study show that: (1) Hefei metropolitan area and its cities show a steady decline and the characteristics of “high in the north and low in the south, high in the west and low in the east”. (2) Most of the subsystems in the Hefei metropolitan area and the cities show a decreasing trend, with its resistance factors mainly concentrated in the QS system. (3) There is club convergence in Hefei metropolitan area. When the type of adjacent domain is higher, the change of risk type is more sensitive.

With the over-exploitation of mineral resources leading to major conflicts such as water shortage, water quality deterioration, and water ecology deterioration, the risks arising from water ecology in mining areas have received extensive attention from scholars at home and abroad. Using the Web of Science core collection as the data source, 1939 papers from 2007-2021 were used as research objects. CiteSpace and VOSviewer were used to draw a knowledge map for literature visualization and analysis, with the aim of exploring the inner rules, research hotspots and evolutionary trends in the field of water ecology risks in mining areas. The study shows that: (1) The number of publications has been steadily increasing, with China being the country with the highest number of publications. (2) Many studies are conducted within research teams, but cooperation between teams is not strong enough. (3) The current research area has shifted from single substances to coupled research on multiple substances generated by mining. (4) Pollutants from mining areas have a direct impact on the ecological and health safety of humans.

Studying the ecosystem service value is of great value for solving the contradiction between ecological protection and economic development in the Huaihe River Basin. The characteristics of land use change were studied by using the Landsat remote sensing image data of Anhui section and Henan section of Huaihe River Basin from 2010 to 2020. The equivalent factor method was used to estimate the ecosystem service value, and the spatial autocorrelation model was used to analyze the spatial distribution characteristics of ecosystem service value The GM-BP model was used to predict the land use change in 2025. The results showed that: (1) From 2010 to 2020, cultivated land and construction land dominated the land use in the study area, and the degree of land use change changed from severe to stable. (2) The value of ecosystem services is in the transition stage from low level (II) to medium level (III). (3) ecosystem service value has a significant positive spatial correlation, and the spatial distribution is generally high in the southeast and low in the northwest. (4) Compared with 2020, ecosystem service value will rise by 0.54 % in 2025.

With the continued increase in international students in China, the problem of their academic adaptation has become increasingly prominent. Analysis of the factors affecting the academic adaptation of international students and corresponding management practices can suggest measures to improve their academic adaptability. Based on grounded theory, this paper first summarizes the four main factors affecting the academic adaptation of international students, then uses structural equation modeling to construct a model of academic adaptation of international students that is tested and verified by a questionnaire survey of 2540 international students in China (51% male, 49% female). The main conclusions of this paper are as follows: (1) learning communication, course learning, and self-regulation are the main factors affecting the academic adaptation of international students, of which course learning is the most important factor; (2) academic communication and course learning have significant positive effects on self-regulation, while academic communication, course learning, and self-regulation have significant positive effects on the academic adaptation of international students; and (3) there was no significant difference in academic adaptation between genders, though there were significant differences by age. Among them, the mean score for overseas students is the largest for those older than 41 years (M = 4.79; SD = 0.33), showing that these students are most adaptable to study. Accordingly, this study advances policy suggestions for strengthening international students’ academic adaptation on the part of both universities and the government to improve the academic adaptation ability of international students in China.

With the gradual formation of the open pattern of higher education, the issue of the cultural integration of international students has attracted increasing attention. This paper conducts a questionnaire survey of 2000 international students in East China and used factor analysis and structural equation modeling to determine the effects of life adaptation, interpersonal communication, and the training system on cultural integration, with possible moderation by study adaptation to explore the cultural integration of international students. The study found that the cultural integration of international students is jointly affected by multiple realistic factors, among which life adaptation and interpersonal communication are the primary factors. Furthermore, the training system has an important impact on the cultural integration of international students through study adaptation. Accordingly, we argue that universities should strengthen the informal organization and guidance of international students, enhance individual adaptability, promote international exchange, cooperation, and policy regulation of international students, and improve their training system. Moreover, efforts are needed to improve the study adaptability of international students so as to comprehensively address the problem of the cultural integration of international students and improve their education level.

Coal cities are the impetus and guarantee of China's economic development. However, the longterm unreasonable exploitation of coal seriously affects the quality of eco-environment and residents' lives in coal cities. This study takes five coal cities in Anhui Province as the research objects, selects ten evaluation indicators of three dimensions based on the production-life-ecology (PLE) model, and improves the evaluation model of relative resource carrying capacity (RRCC). The relative carrying capacity (RCC) of various resources and the relative resource comprehensive carrying capacity (RRCCC) in coal cities from 2010 to 2019 are calculated by entropy-catastrophe progression method to explore the spatio-temporal dynamic evolution of RRCCC in each city, and the critical resistance factors are identified by resistance model. The results show that: (1) There is a particular gap between the RCC of various resources and the existing population resources. (2) RRCCC, with a good development trend in general, is at a relatively strong load level, tending to a strong load level. (3) The level of RRCCC in each city is unevenly distributed, with regional differences. (4) The ecological subsystem had the most significant impact on RRCCC before, and it will be replaced by the production subsystem in the future.