The conversion of lignin into valuable products has attracted the interest of researchers. A series of modified polyurethane adhesives were prepared by blending corn straw enzymatic hydrolyzed lignin with polyester polyol and tolylene-2,4-diisocyanate. Mechanical properties, chemical structures, and thermal stability of the adhesives were characterized by mechanical properties tests, Fourier transform infrared spectrometry (FTIR), and thermogravimetric analysis (TGA). The results of shear strength test under room temperature and high temperature showed that the shear strength for modified polyurethane adhesives was improved by introduction of lignin. The introduction of lignin also improved the heat resistance of polyurethane adhesive. The TGA analysis results showed there were two stages in the thermal decomposition of the lignin blend modified polyurethane adhesive, and the maximum decomposition temperature of the first stage increased with the increase of lignin content, while the maximum decomposition temperature of the second stage decreased with the increase of lignin content. The TGA-FTIR combination analysis studied the main gas generated in the two decomposition stage’s peak times, of which CO2 was produced in the first stage, and CH4 was created in the second stage, indicating that the molecular chain fracture process of the two kinds of adhesives was similar in the whole decomposition process.

High-speed overloading puts forward very strict requirements on the bending strength of spiral bevel gears, and shot blasting is a technological process method to increase gear bending fatigue strength significantly. During the process of shot blasting, a large number of tiny pellets bombard metal target material surface at very high speed in order to let the target material form plastic deformation and form strengthened layer at the same time. As the bombarded target, the microstructure of gear surface spiral bevel gear is inevitably changed. This paper aims at revealing how the shot peened surface microstructure of the spiral bevel gear affects lubrication of gear and establishes a reasonable microstructure description model of the shot blasting surface of the spiral bevel gear, revealing the tribological characteristics of spiral bevel gears after shot blasting treatment based on the elastohydrodynamic lubrication theory. Also, comparative research is carried out on a variety of lubrication characteristics of the microstructure surface.

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Impact of Oleanolic Acid on Myocardial DamageOne of the leading causes of diabetes-related deaths is myocardial damage, which may be the cause of heart failure in people with type 2 diabetes mellitus. The objective of the research was to look at the impact of coronary failure with kind a pair of type 2 diabetes mellitus. This project aimed to explore the protective impact of oleanolic acid on myocardial damage in type 2 diabetes mellitus and to investigate the connected mechanism. Specific pathogen free grade db/db male mice were elected as model, while the Db/m mice were opted for control. Different doses of drug intervention were performed and the general condition, cardiac function, blood glucose, blood lipids, degree of myocardial injury, and degree of oxidative stress were examined by morphological examination of myocardial tissues, biochemical examination, and gene and protein amount detection. The results showed that lactate dehydrogenase, creatine kinase isoenzyme, total cholesterol, triglycerides and malondialdehyde levels in serum of Db/db mice were increased, while phosphatidylinositol 3 kinase, protein kinase B, glucose transporter 4 expression and superoxide dismutase level in myocardial tissue were decreased. After using oleanolic acid, the serum concentrations of lactate dehydrogenase, creatine kinase isoenzyme, total cholesterol, triglycerides and malondialdehyde were declined in Db/db mice, while phosphatidylinositol 3 kinase, protein kinase B, glucose transporter 4 expression and superoxide dismutase level were rised. The results recommend that oleanolic acid has protective impact on cardiac muscle injury in Db/db mice and conjointly the mechanism could also be correlated with promoting the activation of phosphatidylinositol 3 kinase/protein kinase B/glucose transporter 4 signal transduction.