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China has highly emphasized the research and operational application of numerical weather prediction. This paper determines the objective function parameters, such as CAPE and SRH, to apply an ensemble numerical prediction model in weather forecasting. Preprocessing and evaluating rainfall data is necessary to construct the WRF-ARW numerical weather prediction model. The WRF-ARW model is applied to simulate the weather forecasts in Henan Province, and the difficulties and challenges faced in the efficient implementation of the parameterized scheme are outlined. The WRFARW model’s prediction errors for the maximum rainfall and total rainfall in Henan Province range from 1.78%-13.51% and 0.16%-3.78%, respectively, which are significantly less than 15%, and the model is more predictive than the others. The raw data test set’s credibility ranges from 0.957 to 0.997, which is close to 1, indicating that the raw data collected in this paper are highly credible. The WRF-ARW model’s qualification rates for forecasting maximum rainfall and total rainfall are 86.7% and 93.3%, respectively, and its overall accuracy is grade B and grade A, respectively. The pass rates for the peak occurrence time of maximum rainfall and total rainfall were 93.3% and 86.7%, respectively, and the overall prediction accuracy was Grade A and Grade B, respectively. The WRF-ARW model is effective in weather forecasting throughout Henan Province. In summary, the WRF-ARW model is very effective in improving the efficiency of ensemble numerical weather prediction and parameterization schemes in Henan Province.

Amidoxime-functionalized hydrogels are one of most promising adsorbents for high-efficiency uranium (U) extraction from seawater, but bioadhesion on their surface seriously decreases their adsorption efficiency and largely shortens their service life. Herein, a semi-interpenetrating zwitterion–poly(amidoxime) (ZW-PAO) hydrogel was explored through introducing a PAO polymer into a poly [3-(dimethyl 4-vinylbenzyl amino) propyl sulfonate] (PDVBAP) polyzwitterionic (PZW) network via ultraviolet (UV) polymerization. Owing to the anti-polyelectrolyte effect of the PZW network, this ZW-PAO hydrogel can provide excellent super-hydrophilicity in seawater for high-efficiency U-adsorption from seawater. Furthermore, the ZW-PAO hydrogel had outstanding anti-biofouling performance for both highly enhanced U-adsorption and a relatively long working life in natural seawater. As a result, during only 25 days in seawater (without filtering bacteria), the U-uptake amount of this ZW-PAO hydrogel can reach 9.38 mg/g and its average rate can reach 0.375 mg/(g∙day), which is excellent among reported adsorbents. This work has explored a promising hydrogel for high-efficiency U-recovery from natural seawater and will inspire new strategy for U-adsorbing materials. [ABSTRACT FROM AUTHOR]

Combining mine exhaust waste heat with existing heat pump technology is a promising technical route to realise the efficient extraction and scientific use of low-grade waste heat resources in mines and to solve the problem of insufficient heat supply in remote mining areas. This study proposes a new type of mine-exhaust-air heat exchange coupled with heat-pump waste-heat-utilisation system based on deep enthalpy heat extraction. Using a mining area in Northwest China as a representative case, this study establishes a systematic exergy analytical model and a thermo-economic model. Through an in-depth analysis of the different evaporation temperatures and condensing temperatures, the system's energy efficiency ratio (COP) reaches its optimal performance, with the total exergy efficiency surpassing 90%. The minimum efficiency of the subsystem return air heat exchanger is 35%. The unit thermal costs of the mine exhaust air waste heat utilisation system and a conventional coal-fired boiler system are 0.1291 and 0.1573 million RMB/kW·h, respectively. This is a thermal economics cost saving of 21%. The studied system demonstrates great economic viability and the potential for energy saving throughout its life cycle. [ABSTRACT FROM AUTHOR]

Aliphatic‐aromatic copolyesters offer a promising solution to mitigate plastic pollution, but high content of aliphatic units (>40 %) often suffer from diminished comprehensive performances. Poly(butylene oxalate‐co‐furandicarboxylate) (PBOF) copolyesters were synthesized by precisely controlling the oxalic acid content from 10 % to 60 %. Compared with commercial PBAT, the barrier properties of PBOF for H2O and O2 increased by more than 6 and 26 times, respectively. The introduction of the oxalic acid units allowed the water contact angle to be reduced from 82.5° to 62.9°. Superior hydrophilicity gave PBOF an excellent degradation performance within a 35‐day hydrolysis. Interestingly, PBO20F and PBO30F also displayed obvious decrease of molecular weight during hydrolysis, with elastic modulus >1 GPa and tensile strength between 35–54 MPa. PBOF achieved the highest hydrolysis rates among the reported PBF‐based copolyesters. The hydrolytic mechanism was further explored based on Fukui function analysis and density functional theory (DFT) calculation. Noncovalent analysis indicated that the water molecules formed hydrogen bonding interaction with adjacent ester groups and thus improved the reactivity of carbonyl carbon. PBOF not only meet the requirements of the high‐performance packaging market but can quickly degrade after the end of their usage cycles, providing a new choice for green and environmental protection. [ABSTRACT FROM AUTHOR]

High performance copolyesters with ultrahigh glass transition temperature (Tg) are crucial in emerging technology fields such as electronic devices, automotives, and coatings. In this paper, a series of poly(ethylene bis[4‐(2‐hydroxyethoxy) phenyl] sulfone 2,6‐naphthalate) (PESNs) with high Tg are synthesized by the copolymerization of 2,6‐naphthalenedicarboxylic acid (2,6‐NDA), bis[4‐(2‐hydroxyethoxy) phenyl] sulfone (BHEBS), and ethylene glycol (EG). The chemical structure and compositions of prepared copolymers are confirmed by hydrogen nuclear magnetic spectra (1H NMR). Tg of copolyesters (121.1–152.2 °C) depends on composition and is comparable to that of polyetheretherketone (PEEK: 143 °C), increasing as the amount of BHEBS units is increased. The Fox, Gordon–Taylor, and Kwei equations are employed to evaluate the variation of Tg with respect to the composition of PESNs, respectively. In these three equations, the data calculated by Kwei equation fit the actual results best, attributed to the peculiar dielectric properties. In addition, PESNs show good solubility in 1,1,2,2‐tetrachloroethane, DMF, and DMSO, which is conducive to meet the needs of polyester coating. [ABSTRACT FROM AUTHOR]

In this work, dioctyl 2,5‐thiophenedicarboxylate (DOT), a potentially bio‐based plasticizer, was synthesized and evaluated as an alternative to traditional petroleum‐based plasticizers. The chemical structure of DOT was confirmed by FTIR and 1H NMR. Besides, its plasticization effect on poly(vinyl chloride) (PVC) was investigated in detail, and dioctyl 2,5‐furandicarboxylate (DOF) as well as dioctyl isophthalate (DOIP) with similar chemical structures were used as references. The DMA results showed that the glass transition temperature (Tg) of PVC/DOT, PVC/DOF, and PVC/DOIP was 45.1°C, 33.6°C, and 51.3°C, respectively, indicating that the plasticizing efficiency of DOT was better than that of DOIP but lower than that of DOF. However, the tensile test results exhibited that the elongation at the break of PVC/DOT was higher than that of PVC/DOF, which was attributed to the easy phase separation between DOF and PVC. In addition, DOT displayed the best volatility resistance and exudation resistance among the three plasticizers, attributed to its highest molecular weight. Moreover, the migration loss of DOT in non‐polar solvents was much smaller than that of DOIP because of its stronger molecular polarity. In conclusion, DOT has good potential to replace traditional petroleum‐based plasticizers and be used as a primary plasticizer for PVC. [ABSTRACT FROM AUTHOR]