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Dye is an organic substance that seriously threatens the water environment. Using a solvothermal technique, MIL‐100(Fe) and M‐Fe have been synthesized to effectively remove methylene blue (MB) and methyl orange dyes from wastewater. The microstructures of the two products were analyzed using scanning electron microscopy, Fourier transform infrared, Brunauer–Emmett–Teller (BET), thermogravimetric (TG), and X‐ray diffractometer (XPS) test. Optimized the optimal experimental parameters through batch processing experiments, when the pH was 5 and 2, the amount of adsorbent was 50 mg, the temperature was 25°C, and the dye concentration was 30 mg/L, MIL‐100(Fe) and M‐Fe had the highest removal rates of MB, at 98.95% and 94.11%, respectively. Adsorption process was well described by the Freundlich isotherm and pseudo‐second‐order kinetics. After three regeneration experiments, the removal rate was still high. The removal efficiencies of the two adsorbents for MB were similar. However, the regeneration performance of M‐Fe was better. Through the simulation of materials studio, the adsorption energy of the product and MB is −0.93 eV, which is favorable for adsorption. The results show that the two adsorbents can effectively remove MB from wastewater and have broad application prospects.

China is a major coal producer, with huge differences in coal production and safety situations between the South and the North. Taking province A as an example, its coal enterprises have low output, poor efficiency, backward equipment, and low-quality personnel. The output accounts for 0.08% of the country, and the number of deaths accounts for 2.2% of the country, the safety situation of coal enterprises in province A is severe. In order to study the safety risk situation of coal mines under difficult conditions, this paper screens 98 factor indexes including multiple subjects such as enterprise managers, front-line workers, government supervisors, external environment, work quality, stress factors, economic factors, and other dimensions. For different data, the indicator weights were calculated using triangular fuzzy number, entropy weight method, CRITIC method, and three rough set methods in a total of six methods. The comprehensive weights of the indicators were obtained using the proposed new comprehensive weight method. The current situation of safety work of four coal mining enterprises and three levels of government supervision departments was evaluated, and the evaluation results were compared with other existing data to verify the reliability of the evaluation system. The horizontal comparison of the evaluation results indicates the main problems of each subject; the longitudinal comparison points out the problems that need to be solved with the assistance of higher-level enterprises and the central government, and corresponding suggestions for coal mining enterprises and government departments are put forward to reduce the safety risks of troubled coal mining enterprises.

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