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Carbon dioxide (CO2) fixation into value-added chemicals has attracted growing attention and one promising atom-efficient pathway is via the cycloaddition with three member-ring compounds like epoxides. Herein, we demonstrated that encapsulation of linear poly(ionic liquid)s (PILs) on ordered mesoporous carbon materials provides a facile and feasible approach towards environmental-friendly heterogeneous catalysts with high performance in CO2 cycloaddition with epoxides under mild conditions. A series of novel linear phenolic hydroxyl group functional imidazolium-based PILs synthesized from hydroxymethylation reaction between 4-(imidazol-1-yl)phenol-1-butyl-imidazolium iodide and formaldehyde was loaded on ordered mesoporous carbon FDU-15–600 derived from mesoporous phenolic resin. By virtue of controlling the initial polymerization temperature, the molecular weight of PILs was facilely modulated, reaching strong host–guest interaction during the PIL immobilization. Highly stable immobilized PIL species with spatial satisfaction of ionic moieties and surface groups were thus realized to enable a synergic CO2 conversion via cycloaddition with epoxides. The optimal catalyst exhibited high yield and stable recyclability by using atmospheric CO2 under metal-additive-solvent-free conditions and the activity surprisingly exceeded the corresponding homogeneous parent IL and PIL. Excellent substrate compatibility was found by extending the transformation of more than ten epoxides including the inert ones such as disubstituted cyclohexene oxide. The significantly enhanced activity is attributed to the synergistic effect of the surface hydrogen groups and ionic moieties to accelerate the rate-determining ring-opening process.

Xinjiang is an important power production base in China, and its electric energy production needs not only meet the demand of Xinjiang's electricity consumption, but also make up for the shortage of electricity in at least 19 provinces or cities in China. Therefore, it is of great significance to know ahead of time the electric energy production of Xinjiang in the future. In such terms, accurate electric energy production forecasts are imperative for decision makers to develop an optimal strategy that includes not only risk reduction, but also the betterment of the economy and society as a whole. According to the characteristics of the historical data of monthly electricity generation in Xinjiang from January 2001 to August 2020 , the suitable and widely used SARIMA (Seasonal autoregressive integrated moving mean model) method and Holt-winter method were used to construct the monthly electric energy production in Xinjiang for the first time. The results of our analysis showed that the established SARIMA((1,2,3,4,6,7,11),2,1)(1,0,1)12 model had higher prediction accuracy than that of the established Holt-Winters' multiplicative model. We predicted the monthly electric energy production from August 2021 to August 2022 by the SARIMA((1,2,3,4,6,7,11),2,1)(1,0,1)12 model, and errors are very small compared to the actual values, indicating that our model has a very good prediction performance. Therefore, based on our study, we provided a simple and easy scientific tool for the future power output prediction in Xinjiang. Our research methods and research ideas can also provide scientific reference for the prediction of electric energy production elsewhere.

To understand the potential risks of heavy metals, including their bioavailability and toxicity, 15 surface sediment samples were collected from Luhun Reservoir in Luoyang city, China. Total concentrations and chemical fractions of Cd, Cr, Cu, Ni, Pb, and Zn were analyzed. Various rating methods were used to evaluate the degree, risk, and toxicity of the heavy metal pollution. Results showed that Cd and Pb were preferentially associated with exchangeable (55.77–69.76%) and reducible (53.54–69.43%) fractions, respectively, and therefore exhibited high potential availability. Cr (57.14–86.56%) and Ni (32.21–72.77%) occurred primarily in the residual fraction. Metal concentrations in the effective fraction of the sediment decreased in the order: Cd (96.32%) > Pb (91.61%) > Cu (64.54%) > Zn (57.23%) > Ni (41.51%) > Cr (21.68%). Risk assessment indicated that the risk for Cd is extremely high (62.96%); Cu, Pb, and Zn are ranked as medium risk. Based on the potential ecological risk index, these metals (especially Cd) showed higher potential risk near the dam region. Toxic unit values (2.89–6.05) in more than 60% of sediment sites exceeded a value of 4, and Pb had a relatively higher contribution (1.06–2.65). Cd and Pb are the main contaminants in sediments of Luhun Reservoir and should be paid more attention in the future.