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AISI 1045 steel has the characteristics of high strain rate, large strain, and sharp rise in temperature during high-speed deformation process, resulting in a concentrated deformation band and fine structure. In this work, the microstructure of submicron-sized grains in AISI 1045 steel material formed under 10 6 s –1 during a high speed cutting process was examined. To reveal the dynamic evolution mechanism of the AISI 1045 microstructure, the continuous dynamic recrystallization theory was introduced. The results show a high dislocation density which favor the formation of small angle grain boundaries during the high speed cutting process. Kinetics calculations that use continuous dynamic recrystallization mechanisms prove that the recrystallization size is constant when the strain rate ncreases from 10 3 s –1 to 10 6 s –1, and the transition time is reduced from 6×10 –5 s to 4×10 –8 s. The recrystallization grains were gradually formed during the deformation of the material, not generated after the deformation.

In this study, phosphate rock and iron powder were used as raw materials, and industrial silicon is used as a reducing agent. Through orthogonal experiments, the effects of smelting temperature, holding time and silicon ratio on the carbon content, titanium content, phosphorus content and the recovery rate of phosphorus in ferro-phosphorus alloy products are studied. The results show that the carbon content in ferro-phosphorus alloys obtained in the experiment is less than 0.043%, and the titanium content is less than 0.036%. The order of the degree of influence of various factors on the phosphorus content and the recovery rate of phosphorus from large to small is: silicon ratio, smelting temperature, holding time. The best process conditions for preparing ferro-phosphorus alloy by electro-silicothermic process are smelting temperature of 1390 ℃, holding time of 60 min, and silicon ratio of 1.2. Under these conditions, the ferro-phosphorus alloy has a carbon content of 0.010%, a titanium content of 0.036%, and a phosphorus content of 27.78%. The recovery rate of phosphorus was 96.49%.

Corn silk (CS) is known to reduce cholesterol levels, but its underlying mechanisms remain elusive concerning the gut microbiota and metabolites. The aim of our work was to explore how altered gut microbiota composition and metabolite profile are influenced by CS intervention in mice using integrated 16S ribosomal RNA (rRNA) sequencing and an untargeted metabolomics methodology. The C57BL/6J mice were fed a normal control diet, a high-fat diet (HFD), and HFD supplemented with the aqueous extract of CS (80 mg/mL) for 8 weeks. HFD-induced chronic inflammation damage is alleviated by CS extract intervention and also resulted in a reduction in body weight, daily energy intake as well as serum and hepatic total cholesterol (TC) levels. In addition, CS extract altered gut microbial composition and regulated specific genera viz. Allobaculum, Turicibacter, Romboutsia, Streptococcus, Sporobacter, Christensenella, ClostridiumXVIII, and Rikenella. Using Spearman’s correlation analysis, we determined that Turicibacter and Rikenella were negatively correlated with hypercholesterolemia-related parameters. Fecal metabolomics analysis revealed that CS extract influences multiple metabolic pathways like histidine metabolism-related metabolites (urocanic acid, methylimidazole acetaldehyde, and methiodimethylimidazoleacetic acid), sphingolipid metabolism-related metabolites (sphinganine, 3-dehydrosphinganine, sphingosine), and some bile acids biosynthesis-related metabolites including chenodeoxycholic acid (CDCA), lithocholic acid (LCA), ursodeoxycholic acid (UDCA), and glycoursodeoxycholic acid (GUDCA). As a whole, the present study indicates that the modifications in the gut microbiota and subsequent host bile acid metabolism may be a potential mechanism for the antihypercholesterolemic effects of CS extract.