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The suppression of photogenerated carrier recombination in carbon nitride and the consequent enhancement of its photocatalytic hydrogen evolution performance have emerged as a research hotspot in the field of photocatalysis. Herein, Nickel phosphide (Ni 2 P) was anchored onto carbon nitride with carbon defects through a synthesis involving thermal polymerization and photoreduction. The existence of carbon defects derived from the rupture of carbon nitride (CN) heterocycles were beneficial to strengthening optical absorption and the separation capabilities of photogenerated carriers. Furthermore, Ni 2 P cocatalysts could serve as electron acceptors that effectively accelerate the transfer and transport capabilities of the photogenerated charge carriers. Consequently, the 7 wt% Ni 2 P/CNN photocatalyst achieved a maximum hydrogen evolution rate of 2062 μmol·g−1·h−1, which was 7.8 times and 6.2 times greater than that of Ni 2 P/CN and Ni/CNN, respectively, and was comparable to the rate achieved by 3 wt% Pt/CNN. This result was comparable or even better than those reported previously. Our work provided a simply strategy for developing non-precious metal-based nickel phosphide photocatalysts for renewable solar-driven photocatalytic hydrogen production. [Display omitted] • Ni 2 P/CNN photocatalyst was prepared by hydrothermal and thermal polymerization combined with photoreduction method. • The synergistic effects of carbon defect of carbon nitride and Ni 2 P boost the photocatalytic hydrogen production. • Ni 2 P cocatalyst served as electron acceptors to accelerate the separation capabilities of photogenerated charge carriers. • The introduction of carbon defects enhanced optical absorption and acceleration separation rate of photogenerated carriers. [ABSTRACT FROM AUTHOR]

• Dynamic loaded tooth contact analysis (DLTCA) for computing entrainment speed. • Accurate solution to elastohydrodynamic lubrication (EHL) governing equation. • Discrete convolution and fast Fourier transformation (DC-FFT) for flank elastic deformation. • A separation flow method for iteration of EHL governing equation. • Accurate entrainment effect-based EHL forecasting model for hypoid gears. In full consideration of time-varying meshing performance and oil film characteristics, entrainment effect on elastohydrodynamic lubrication (EHL) is developed for establishing accurate forecasting model of the complex hypoid gears. Firstly, dynamic loaded tooth contact analysis (DLTCA) is employed to determine the meshing interface kinematics, load distribution and entrainment speed under dynamic load condition. Then, entrainment speed is introduced into the EHL governing equation and accurate forecasting model is established. With accurate discretization of EHL governing equation, discrete convolution and fast Fourier transformation (DC-FFT) method is employed to compute the flank elastic deformation. Finally, a hypoid gear set in automotive industrial application is exercised to verify entrainment effect on EHL assessment in the proposed model. [ABSTRACT FROM AUTHOR]

This study employed the DFT method to calculate the catalytic activity of various organic functional groups during phenol production on seaweed biochar. It also used machine learning to analyze the correlation between electronic structure parameters of different sites and their catalytic activity. Finally, it summarized the essential characteristics of the most active site. [Display omitted] • Establishing cluster models of algal biochar catalyst and its catalytic mechanisms for lignin upgrading using a DFT method. • Decision trees, random forests, gradient boosting, and extreme gradient boosting were used to establish prediction models. • The random forest method performs best in revealing catalyst reactivity. • Fukui function is an effective descriptor for evaluating the reaction activity of adsorption sites. With the continuous development of the industrialization process, the reserves of primary energy sources such as petroleum have sharply decreased. The development of efficient and economical catalysts is of great significance in promoting the rapid pyrolysis of biomass to produce high-quality liquid fuels and chemicals. In this study, density functional theory (DFT) and machine learning (ML) were used to explore the catalytic reaction mechanism of guaiacol pyrolysis over seaweed biochar catalyst. Models of algae biochar catalysts with oxygen-containing or nitrogen-containing functional groups were established, and the surface transformation mechanism of guaiacol over the biochar catalyst was calculated using DFT. Furthermore, four machine learning methods (decision tree (DT), random forest (RF), gradient boosting (GB), and extreme gradient boosting (XGBoost)) were used to establish a mathematical model based on catalyst characteristics for predicting key intermediate adsorption energy during catalysis reaction. The fitting results and performance analysis of each prediction model show that the RF method-trained model has the highest accuracy. Fukui function (f-) was proved as an effective descriptor to evaluate the reactivity of adsorbed sites. This study provides a pathway to developing more efficient biochar catalysts, which could lead to more sustainable and environmentally friendly energy solutions. [ABSTRACT FROM AUTHOR]

[Display omitted] • The carbon quantum dot is employed as cocatalyst to boost the catalytic oxidative desulfurization of phosphotungstic acid ionic liquid. • The carbon quantum dot favors the activation of hydrogen peroxide. • The CQDs/C 18 PWIL-1 exhibits excellent desulfurization efficiency under ambient conditions, in which dibenzothiophene was completely removed within 30 min. SO x emission from fossil fuel combustion is an important reason for environmental pollution. Achieving deep removal of sulfur-containing compounds from the fuel is essential. Herein, by combining phosphotungstic acid (HPW) with ionic liquids (ILs) and incorporating carbon quantum dots (CQDs), a series of catalysts (CQD/C 18 PWIL-x) for oxidative desulfurization (ODS) are prepared. Experimental results reveal that the modification of ILs could facilitate full contact between the active site and the organic phase, and improve mass transfer in the oxidative desulfurization process. Moreover, the incorporation of CQDs can promote the utilization of hydrogen peroxide. The synergistic action of multiple components leads to better activation of hydrogen peroxide. Therefore, the CQDs/C 18 PWIL-1 exhibits excellent desulfurization efficiency under ambient conditions, in which dibenzothiophene was completely removed within 30 min. Meanwhile, as heterogeneous catalyst, CQDs/C 18 PWIL-1 shows excellent cycling stability. The direct incorporation of CQDs significantly improves the catalytic activity and provides a new inspiration for the application of CQDs to ODS processes. [ABSTRACT FROM AUTHOR]

For hypoid gear transmission showing time-varying meshing characteristics, three always is a very complicated solid-liquid-thermo-mechanical coupling lubrication interface behavior. In full consideration of tooth flank roughness and non-Newton fluid effect for this thermal elastohydrodynamic lubrication (TEHL) interface, an innovative multi-field coupling lubrication interface heat transfer model is established. Firstly, dynamic loaded tooth contact analysis (DLTCA) is performed to determine the input parameters about lubrication interface behavior, such as meshing interface kinematics, load distribution and entrainment speed parameters. Then, considering tooth roughness setup and non-Newton fluid flow, accurate TEHL interface heat transfer model is developed by establishing three-dimensional (3D) energy equation. Moreover, heat transfer model is solved for time-varying TEHL assessments including oil film pressure, temperature and thickness. Where, a non-Newton fluid effect correction is used to get accurate discretization of oil film pressure flow. In accurate solution to non-Newton fluid effect, an improved Eyring rheological model is employed for accurate computation of comprehensive shear force, flow factor and equivalent viscosity. A column-by-column scanning method is applied to determine the temperature field in a given computational domain. Finally, the numerical instances are provided to verify the proposed model. • DLTCA for basic input parameters determination; • TEHL governing equation considering tooth flank roughness and non-Newton fluid effect; • Computation for roughness tooth flank non-Newton TEHL forecasting equation; • Roughness tooth flank non-Newton TEHL forecasting model; • Time-varying characteristics of TEHL assessments [ABSTRACT FROM AUTHOR]

ZSM-5 supported cobalt tungstate catalyst (CoWO 4 /ZSM-5-DR) was prepared by a facile dissolution-regrowth strategy. The sulfur removal could reach 100% within 5h over the obtained CoWO 4 /ZSM-5-DR. [Display omitted] • CoWO 4 /ZSM-5-DR was prepared via a facile dissolution-regrowth strategy. • The surface structure was reconstructed including the morphology and the pore size. • Removal of DBT could reach 100 % by CoWO 4 /ZSM-5-DR within 5 h. • CoWO 4 /ZSM-5-DR showed superior cycling stability even after 6 cycles. • O 2 •− was deduced as the main active species for the conversion of DBT to DBTO 2. Compared with homogeneous catalysts, heterogeneous catalysts have greater separability and recyclable properties. Yet, the uneven distribution of active sites in the conventional synthetic method is a challenge. Herein, ZSM-5 supported cobalt tungstate catalyst (CoWO 4 /ZSM-5-DR) was prepared by a facile dissolution-regrowth strategy under mild conditions. In comparison to the supported CoWO 4 catalyst generated by impregnation, the catalyst demonstrated a higher desulfurization efficiency in oxidative desulfurization due to the surface structural reconstruction of ZSM-5 and the uniform dispersion of the active substances. The as-prepared CoWO 4 /ZSM-5-DR catalyst can achieve 100 % sulfur removal within 5 h, which exhibits good stability and a high removal rate even after 6 cycles. This work provides new insight into supported binary metal oxide catalysts with highly homogenous dispersion and effectivity. [ABSTRACT FROM AUTHOR]