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When a droplet off-center impacts a macro-ridge, it may split into two asymmetric fragments, i.e., the smaller part (SP) and larger part (LP), which then exhibit asymmetric spreading and receding phenomena. Using lattice Boltzmann method simulations, the dynamics of a droplet off-center impacting a hydrophobic surface are explored for the first time. Influences of the off-center distance, the impact Weber number, and the surface wettability on the impact outcomes and the contact time are elucidated, and the impact regime is established. Six impact outcomes are discovered as off-center distance changes, which are dependent on the interaction force between the droplet and the surface. The effect of the off-center distance and the Weber numbers on the spreading and the receding dynamics of the SP is more obvious than that of the LP, due to the fact that adhesion of the ridge on the LP can be negligible compared to the inertial force and the surface tension. The contact time is closely related to the impact outcomes, that is, when the impact outcome is type 1 (SP and LP separate rebound), the contact time can be significantly reduced compared with that on the flat hydrophobic surface, due to the fact that the ridge can reduce the asymmetry of a liquid film and the receding distance in this case; while when the impact outcome is type 6 (SP and LP completely coalescence and rebound), the contact time cannot be reduced. This work extends the fundamental knowledge of off-center impact and provides inspiration for the efficient reduction in the contact time. [ABSTRACT FROM AUTHOR]

In this study, we experimentally explored the impact outcomes of droplets under a wide range of Weber numbers (0.2 ≤ We ≤ 200) and contact angles (91° ≤ θ ≤ 162°). Five impact outcomes were identified: deposition, rebound, partial rebound, receding breakup, and prompt splash. Compared to the literature, we gathered more comprehensive data on the impact outcomes at various contact angles, which were then organized into a complete phase diagram. Furthermore, we corroborated the accuracy of these outcomes through comparisons with other studies. We conducted a comprehensive analysis of the associated phenomena and underlying mechanisms of these outcomes. By introducing the concept of surface hysteresis energy, we also proposed identification criteria for partial rebound. This innovative approach provides an important reference for further understanding of droplet impact behavior and provides guidance for future research in this field. [ABSTRACT FROM AUTHOR]

This work presents a study of a droplet impacting an inclined hydrophobic surface using lattice Boltzmann method (LBM) simulation. The influence of surface inclination, surface wettability, and the Weber number on the dynamic of spreading and receding is elucidated. Intriguingly, the contact time is independent of the surface inclination. The surface wettability and Weber number do not affect the spreading time, while they significantly influence the receding dynamic. To further quantitatively describe the influence of surface wettability and Weber number, scaling laws of the receding rate are established as Vret ∼ (1 − cos θ)−0.25 and Vret ∼ Wen0.19, and, thus, scaling laws of the receding time are established as tr ∼ (1 − cos θ)−0.5 and tr ∼ Wen0.1, respectively, where Wen is the normal Weber numbers and θ is the contact angle. Based on this, a relationship of the contact time for a droplet impacting an inclined hydrophobic surface is ultimately established as tc = 3.1(ρR03/σ)1/2 (1 − cos θ)−1/2Wen0.1, where ρ, R0, and σ denote the droplet density, radius, and surface tension, respectively. This study provides a quantitative relationship to calculate the contact time of a droplet impacting an inclined hydrophobic surface, which can simultaneously efficiently evaluate the anti-freezing, anti-icing, and self-cleaning performance of hydrophobic surfaces employed in practical applications. [ABSTRACT FROM AUTHOR]

Objective: To observe the synergistic effect of Qilian decoction (QLD) with corresponding hypoglycemic agents on insulin sensitivity in patients with diabetes mellitus type 2 and its influence on related inflammatory cytokines., Methods: Sixty-two patients with diabetes mellitus type 2 were selected and randomly divided into two groups, they were treated with hypoglycemic agent in routine, and QLD was given orally, one dose taken in twice a day. Parameters as fasting blood glucose, insulin, peptide C, tumor necrosis factor-alpha (TNF-alpha), C-reactive protein (CRP), interleukin 6 (IL-6) were measured before and after treatment, and insulin sensitive index (ISI) was also calculated., Results: The level of fasting blood glucose lowered after treatment in both groups (P<0.01); levels of fasting insulin, peptide C, ISI, TNF-alpha, IL-6 and CRP significantly lowered after treatment (P<0.05 or P<0.01), and the effect was better than that in the control group (P<0.05 or P<0.01)., Conclusion: QLD could improve the insulin resistance and lower the levels of related inflammatory cytokines.