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Environmental media affect the atmospheric oxidation processes of phenolic compounds (PhCs) released from biomass burning in the troposphere. Phenol (Ph), 4-hydroxybenzaldehyde (4-HBA), and vanillin (VL) are chosen as model compounds to investigate their reaction mechanism and kinetics at the air-water (A-W) interface, on TiO2 clusters, in the gas phase, and in bulk water using a combination of molecular dynamics simulation and quantum chemical calculations. Of them, Ph was the most reactive one. The occurrence percentages of Ph, 4-HBA, and VL staying at the A-W interface are ~72 %, ~68 %, and ~73 %, respectively. As the size of (TiO2)n clusters increases, the adsorption capacity decreases until n > 4, and beyond this, the capacity remains stable. A-W interface and TiO2 clusters facilitate Ph and VL reactions initiated by the O3 and HO•, respectively. However, oxidation reactions of 4-HBA are little affected by environmental media because of its electron-withdrawing group. The O3- and HO•-initiated reaction rate constant (k) values follow the order of PhA-W > VLTiO2 > VLA-W > 4-HBAA-W > 4-HBATiO2 > PhTiO2 and VLTiO2 > PhA-W > VLA-W > 4-HBATiO2 > PhTiO2 > 4-HBAA-W, respectively. Some byproducts are more harmful than their parent compounds, so should be given special attention. This work provides key evidence for the rapid oxidation observed in the O3/HO• + PhCs experiments at the A-W interface. More importantly, differences in oxidation of PhCs by different environmental media due to the impact of substituent groups were also identified. [ABSTRACT FROM AUTHOR]

Due to the excellent film‐forming specific surface area of the disk reactor, its application in the polymer devolatilization process can greatly improve the devolatilization performance of the equipment. In view of this, the fluid volume function method in computational fluid dynamics is used to simulate the film forming performance and surface renewal performance in high viscosity zone of disk reactor. In the disk window area, the liquid film thickness becomes thinner and the surface update frequency becomes faster, indicating that the disk window has a positive effect. The devolatilization performance of five new disk structures under different operating conditions is compared and analyzed. It was found that the influence of liquid level height on film area was greater than that of viscosity and rotation speed, the porous sector disk has excellent surface renewal performance and the baffle can achieve better mass transfer efficiency at a distance of 45–60 mm from the disk. [ABSTRACT FROM AUTHOR]

Background: Myocardial ischemia-reperfusion (I/R) injury is accompanied by an imbalance in the cardiac autonomic nervous system, characterized by over-activated sympathetic tone and reduced vagal nerve activity. In our preceding study, we pioneered the development of the magnetic vagus nerve stimulation (mVNS) system. This system showcased precise vagus nerve stimulation, demonstrating remarkable effectiveness and safety in treating myocardial infarction. However, it remains uncertain whether mVNS can mitigate myocardial I/R injury and its specific underlying mechanisms. In this study, we utilized a rat model of myocardial I/R injury to delve into the therapeutic potential of mVNS against this type of injury. Results: Our findings revealed that mVNS treatment led to a reduction in myocardial infarct size, a decrease in ventricular fibrillation (VF) incidence and a curbing of inflammatory cytokine release. Mechanistically, mVNS demonstrated beneficial effects on myocardial I/R injury by inhibiting NLRP3-mediated pyroptosis through the M2AChR/OGDHL/ROS axis. Conclusions: Collectively, these outcomes highlight the promising potential of mVNS as a treatment strategy for myocardial I/R injury. [ABSTRACT FROM AUTHOR]