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In order to solve the problem of spontaneous combustion of coal in U-shaped stope during dynamic advance, a multiphysical field coupled mathematical model including the inlet and return airway, working face and goaf is established, and the reasonableness of the model is verified by field measurement data. The simulation analyzed the law of temperature field and oxygen concentration field in the goaf with the dynamic advance of working face, and further studied the influence of surrounding rock temperature, air flow temperature and working face advance speed on the self-heating of coal oxidation in the mining area. The results indicate that the temperature field on the inlet side of the goaf forms the phenomenon of high temperature region tailing in the shape of “wing section” in the process of advancing the working face, and the temperature of the high-temperature area gradually decreases under the effect of compaction of the goaf and heat dissipation of the surrounding rock; the temperature in the goaf continues to rise after the stoppage of mining, but the high-temperature area migrates to the working face; in the early stage of mining, different ventilation temperature has almost no effect on the maximum temperature in the mining area, while in the later stage of mining, the higher the ventilation temperature, the higher the maximum temperature in the mining area; the faster the working face advances, the lower the maximum temperature in the mining area.

In the present study, the nutrient composition of Crassostrea hongkongensis from two oyster fattening areas in Qinzhou Bay, Guangxi was evaluated. And then the metabolism-related gene expression in the mantle, adductor muscle and gill tissues of C. hongkongensis was analyzed, and the correlation between nutrient composition and gene expression was discussed. The results showed that the contents of cholesterol, vitamin A, vitamin E, zinc and some amino acids including phenylalanine, histidine, glutamic acid and alanine of C. hongkongensis in Qinzhou Port fattening area were significantly higher than those in Dafeng River fattening area (P0.05). The heat map of Spearman correlation showed that the gene expression of P5CS, GP and SREBP were positively correlated with the contents of multiple nutrient composition and amino acids, in which the gene expression of GP was significantly positively correlated with energy, fat, cholesterol and vitamins (P

The AlCoCuFeMnNi high-entropy alloy cladding layer with CeO2 was prepared by plasma cladding technology on 45 steel. The microstructure and phase composition of the cladding layer were investigated by XRD, SEM and EDS, and its microhardness and wear property were also tested. The results show that the phase structure of the cladding layer is mainly composed of BCC dendrites and FCC interdendrites. Thermodynamic calculation shows a small amount of AlCoNi phase exists in the cladding layer without CeO2, and a large number of Fe-rich precipitated particles in the dendrites is observed, the hardness value exhibits gradient changes from 260HV0.2 to 420HV0.2, and their friction coefficient is between 0.16 and 0.57. After adding 1%(mass fraction) CeO2, the Fe diffusion decreases into cladding layer, and a 32μm Fe-rich peritectic transition layer is formed on the bottom of the cladding layer. The average hardness value is about 400HV0.2, and their friction coefficient is relatively stable (0.28-0.31). The mass loss of the layer with CeO2 is 74.4% of that without CeO2. The grain refinement strengthening is the main reason of the improvement of wear properties.

The cubic spline interpolation function has good convergence, stability and 2nd-order smoothness. A numerical method for the solutions to nonlinear dynamic systems was constructed with the cubic spline interpolation functions. Advantages and disadvantages were compared between this method and the previous numerical methods for nonlinear dynamic systems, with the error estimation conducted in the 2 numerical examples. The results show that the numerical method derived out of the cubic spline interpolation functions has faster convergence rate and higher accuracy than the existing methods, and has good approximation to the analytical solutions to nonlinear dynamic systems. [ABSTRACT FROM AUTHOR]

Gastric cancer is one of the common malignant tumors of digestive system in our country. The proportion of patients in advanced and late stage is large, and the choice of perioperative treatment program is always difficult in clinic. For most locally advanced gastric cancer, compared with standard radical surgery combined with postoperative adjuvant chemotherapy, perioperative treatment mode may further improve the survival of patients. However, the efficacy of conventional chemotherapy regimen has reached a plateau, while the progress of traditional molecular targeted therapy is relatively slow. In recent years, with the increasing role of immunotherapy in the treatment of advanced gastric cancer, more and more clinical studies have shown that immunotherapy can also achieve better efficacy in perioperative gastric cancer patients. This article reviewed the research progress of immunotherapy in perioperative gastric cancer in recent years.

Superhydrophobic surface is a common extreme wetting phenomenon in nature. It is generally believed that superhydrophobic surface is determined by surface microstructure and chemical composition. Due to its unique non - wettability, superhydrophobic surface had a broad application prospect in change of wettability, drag reduction, liquid drop bounce, heat transfer, evaporation, condensation and other aspects. In this paper, the research results of numerical simulations on the change of wettability, drag reduction, droplet bounce, heat transfer, evaporation, condensation of superhydrophobic surfaces in recent years were reported, and then the commonly used numerical simulation methods in the study of superhydrophobic performance were summarized and evaluated. In addition, their advantages and disadvantages were pointed out as well. Finally, the key points and research directions of numerical simulation research on superhydrophobic properties were put forward.

Objective: To differentiate and identify several species of "Muxiang"., Methods: The main microscopic features and HPLC chromatograms of diagnostic components were studied., Results: Distinguishable characters were found in two methods., Conclusion: The results provide reliable and simple reference for the authentication of raw materials of" Muxiang" species, especially the toxic species.