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In this paper, Large Eddy Simulation (LES) is employed to investigate the evolution characteristics of a spiral jet mill. This study aims to provide a theoretical reference for the numerical simulation and design optimization of spiral jet mills. To evaluate the influence of grids on simulation accuracy, grid convergence index (GCI) analysis was carried out on three sets of non-structural grids with equal proportion refinement. The visualization results demonstrate that the feeding gas traction and jet impact attenuation contribute to momentum conversion from the edge to the central domain, facilitating the development of the central swirl. The cross-scale chamber structure makes the turbulent coherent structure in the swirl evolution tend to be complex and disordered. A large-scale annular swirl is formed by stacking and winding multiple strip vortices. By comparing with the steady-state solution calculated using the k-epsilon model, it is confirmed that the aerodynamic characteristics in the micronization chamber stabilize at 400 ms. At this time, the combined action of the radial and tangential velocity forms a spiral airflow trajectory.

To investigate the use of uniportal video-assisted thoracoscopic surgery (U-VATS) in the treatment of non-small cell lung cancer (NSCLC).

A total of 82 patients with early NSCLC in our hospital from May 2019 to January 2021 were enrolled to this study. Forty-one patients treated with spontaneous breathing U-VATS were the research group (RG), and 41 with conventional thoracoscopy were the control group (CG). Fasting peripheral blood was drawn from patients before (T0), one (T1) and three days after surgery (T2), respectively. White blood cells (WBC), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), matrix metalloproteinase-9 (MMP-9) and T-lymphocyte subsets were measured in the blood. In addition, we counted the conversion rate to open chest and tracheal intubation in the RG, and compared the operation time, intraoperative bleeding, chest drainage, chest tube retention time, antibiotic application time, postoperative hospital stays and complications between groups. Finally, a 1-year prognostic follow-up was performed to record overall survival, chemotherapy rate, and recurrent metastasis rate.

At T1, WBC, IL-6, TNF-α, and MMP-9 were lower in the RG than in the CG, while immune function was better in the RG at T1 and T2 (P<0.05). Complication rates were lower in the RG than in the CG when compared (P>0.05). The prognosis of 1-year overall survival, chemotherapy rate, and recurrence rate were not different between the two groups (P>0.05).

Spontaneous breathing U-VATS can effectively reduce the inflammation and enhance the stability of immune function in NSCLC patients undergoing surgery.

Flow separation in overexpanded single expansion ramp nozzles (SERN) involves complex phenomena, such as shock waves, expansion waves, turbulent boundary layers, and shear layers. Computational fluid dynamics plays a crucial role in studying unsteady flow behaviour in supersonic nozzles, allowing for an investigation into the dynamic flow field characteristics. However, the application of OpenFOAM as a numerical tool for studying SERN in the field of compressible flows, particularly in the overexpansion state where the flow field characteristics are more complex, has received relatively less attention. In this study, the flow field characteristics of an overexpanded SERN under different turbulence models are investigated through a combination of experiments and numerical calculations. The qualitative and quantitative predictive performance of two compressible flow solvers in OpenFOAM, namely, rhoCentralFOAM and sonicFOAM, are compared in terms of flow separation pattern and separation pattern transitions within the overexpanded SERN. The ability of rhoCentralFOAM and sonicFOAM to accurately predict complex flow states is evaluated. Results indicate that the numerical simulations conducted using rhoCentralFOAM and sonicFOAM successfully capture flow separation, separated shock waves, separated bubbles and shear layers for two types of restricted shock separation patterns at the same nozzle pressure ratio (NPR), demonstrating agreement with experimental results. However, sonicFOAM initiates the transition in the separation pattern 0.0773 NPR earlier than rhoCentralFOAM during the whole separation pattern transition process of the SERN. The transition process in sonicFOAM lasts longer and exhibits a greater variation in NPR. SonicFOAM fails to accurately predict certain aspects, such as the pressure rise after the separation bubble, the reattachment shock wave, and tends to overestimat the length of the separation shock length. Consequently, sonicFOAM cannot be recommended as a suitable solver for accurately capturing the separation pattern of an overexpanded nozzle.

In view of the uneven artificial sowing, low sowing, as well as the fact that the existing seeders cannot meet the sowing requirements of Pteris vittata, this paper designed an automatic plug seeder by using the method of spraying and sowing after mixing spores and water. In order to obtain the optimum working parameters of the seeder, response surface method (RSM) was employed to design the experiments and evaluate the results with the purpose of optimizing parameters for improving spraying uniformity. The parameters such as the distance between the nozzle and plug and the nozzle angle and transmission speed were selected, and then the regression equation of spraying uniformity was established. The results showed that the influence of various factors on spraying uniformity coefficient from high to low were nozzle angle, distance between the nozzle and plug and transmission speed. Through the experimental analysis, it can be concluded that when the distance between the nozzle and plug was 11.63 cm, the nozzle angle and the transmission speed were 79.23° and 0.21 m/s, respectively; the seeding uniformity coefficient was the largest, 83.43%. The verification test results indicated that the optimized result was reliable. This study can provide reference for the development of micro seed seeder.