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This paper studies a 120 t converter, focusing on the influence of the CO bubbles generated by the carbon-oxygen reaction during the decarburization process on the stirring action of the melt pool. It examines the effect of the intensity and arrangement of bottom blowing on the homogenization effect, taking into account the dynamics of CO bubbles generated from the carbon-oxygen reaction. Initially, a macroscopic kinetics model for the generation of CO bubbles during the carbon-oxygen reaction in converter steelmaking is established. Subsequently, a water model simulation device for CO bubble generation from the converter's carbon–oxygen reaction is designed, establishing a 120 t converter water model experimental setup with a similarity ratio of 1:8. The main indicator for evaluating the homogenizing effect of the converter is the mixing time, based on which, experimental schemes are designed. Water model experiments are conducted to study the influence of bottom-blowing flow and nozzle arrangement on the melt pool's stirring flow field under the action of carbon-oxygen reaction. The results show that greater generation intensity of CO bubbles from the carbon-oxygen reaction leads to shorter mixing time in the melt pool; when the angular spread of the bottom-blowing elements is small, the bottom-blowing gas flow is relatively concentrated, facilitating stirring in the melt pool. However, increasing the angular spread of the nozzles to a certain extent leads to the dispersion of bottom-blowing energy, making it difficult to form effective stirring; when the bottom-blowing flow is less than 1.5 Nm3/h, the mixing time of the melt pool decreases with the increase of bottom-blowing flow; when the bottom-blowing flow is greater than 1.5 Nm3/h, the mixing time of the melt pool increases with the increase of bottom-blowing flow. In addition, a series of industrial experiments were carried out, and the research results were applied to the actual production process. By comparing the test results after the optimization scheme with the production data of the original process, it was found that the optimization scheme significantly improved the smelting efficiency and reduced the production cost. These research results not only provide a theoretical basis, but also provide practical guidance for the optimization of converter smelting process. [ABSTRACT FROM AUTHOR]

During liver surgery, hepatic blood flow needs to be blocked in order to reduce bleeding, which inevitably results in hepatic ischemia/reperfusion injury (HI/R). Paeoniflorin (PF) is the main active ingredient of the traditional Chinese herbal medicine peony, which has been shown to exert anti-oxidative and anti-apoptotic properties. In the present study, a mouse model of HI/R was generated by clamping the hepatoportal vein, hepatic artery, and hepatic duct of BALB/c mice with a vascular clamp for 30 min, followed by reperfusion for 6 h under anesthesia. Six mice in the three PF treatment groups (5, 10 and 20 mg/kg) were then injected with PF, via the tail vein. A sham group, consisting of six mice that did not undergo the procedure, and a vehicle group, consisting of 6 mice that underwent the procedure but subsequently received injections of physiological saline only, were used as controls. Liver injury was indicated by serum levels of the enzymes alanine transaminase (ALT) and aspartate transaminase (AST). The activities of oxidative stress biomarkers, including superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GSH-PX) and malondialdehyde (MDA), were also measured. Furthermore, the activity of caspase-3 was analyzed in hepatic tissue using a commercial kit. Treatment with PF significantly attenuated HI/R injury histologically, as compared with the vehicle group. In addition, significant reductions in the serum levels of ALT and AST were observed in the PF-treated ischemic mice. Furthermore, treatment with PF enhanced the activities of hepatic tissue SOD, GSH and GSH-PX, but decreased the MDA content. Treatment of ischemic mice with PF markedly reduced the expression levels of inflammatory mediators, including nuclear factor-κB, tumor necrosis factor-α, interleukin (IL)-6, and IL-1β, and decreased the HI/R injury-induced expression of caspase-3. The results of the present study suggest that PF attenuates the HI/R injury of mice via anti-oxidative, anti-inflammatory and anti-apoptotic activities.