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Liquid mobility on fibers is critical to the effectiveness of fiber matrices in face masks, water harvesting and aerosol filtration, but is typically affected by Plateau-Rayleigh instability. However, the spontaneous flow within precursor films arising from this instability has been largely overlooked, particularly regarding its fundamental flow pattern and the potential for liquid mobilization. This study reveals the pivotal role of spontaneous flow on ribbon-like fibers in enhancing liquid transport. The non-axisymmetric curvature of these fibers induces long-wave instabilities, generating a sustained flow that enables film-wise transport over centimeter-scale distances at velocities of several millimeters per second. Using particle-image velocimetry, we uncover intricate hydrodynamics, including opposing flows within the film and organized vortices in the shear layer, driven by capillary effects at the liquid-vapor interfaces. Building on these insights, we demonstrate a network structure capable of achieving planar liquid transport over a 10 cm2 area. The ribbon-like fibers investigated exhibit the longest transport distances relative to biomimetic structures and aerodynamic propulsion. The unique transport dynamics and planar configuration of the fiber matrix offer substantial potential for advanced fiber-based liquid transport systems, with enhanced mass/heat transfer, laminar mixing and aerodynamic characteristics.

Recent guidelines by WHO recommend delaying non-essential oral health care amid COVID-19 pandemic and call for research on aerosol generated during dental procedures. Thus, this study aims to assess the mechanisms of dental aerosol dispersion in dental offices and to provide recommendations based on a quantitative study to minimize infection transmission in dental offices. The spread and removal of aerosol particles generated from dental procedures in a dental office are measured near the source and at the corner of the office. We studied the effects of air purification (on/off), door condition (open/close), and particle sizes on the temporal concentration distribution of particles. The results show that in the worst-scenario scenario it takes 95 min for 0.5 um particles to settle, and that it takes a shorter time for the larger particles. The indoor air purifier tested expedited the removal time at least 6.3 times faster than the scenario air purifier off. Airborne particles may be transported from the source to the rest of the room, even when the particle concentrations in the generation zone return to the background level. These results are expected to be valuable to related policy making and technology development for infection disease control in dental offices and similar built environments., Comment: 9 figures 4 tables

Understanding the behavior of entities is critical to the development of new policies and technologies aiming at global health and wellbeing; this paper presents a unified model developed and validated for the deposition of entities, ranging from a few Angstroms to tens of nanometers,on nanofibers. The transport of entities is based on convective diffusion and interfacial interactive diffusion. As the size of entities decreases to intermediate sizes - between gas molecules and nanoparticles - adhesion probability on the surface is less than unity, which is determined by the interfacial interactions and kinetics of adhesion. Dimensionless surface coverage provides a better understanding of adhesion kinetic by considering the effects of initial concentration and time. The model is validated by available experimental data in the literature.