Pushing Droplet Through a Porous Medium
Ontology highlight
ABSTRACT: Supplementary Information
The online version contains supplementary material available at 10.1007/s11242-021-01705-z.
SUBMITTER: Matyka M
PROVIDER: S-EPMC8546388 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:The addition of gyrotactic microbes in the nanoparticles is essential to embellish the thermal efficiency of many systems such as microbial fuel cells, bacteria powered micro-mixers, micro-volumes like microfluidics devices, enzyme biosensor and chip-shaped microdevices like bio-microsystems. Porous media also plays a pivotal role in augmentation of the thermal efficiency. Our approach in the present work is to offer a novel study of bioconvection due to gyrotactic microbes in a nanofluid flow comprising thermal radiation within a porous media over a nonlinear shrinking/stretching surface. The entire coupled system involving nonlinear equations is tackled by means of Successive over Relaxation technique. The impacts of the involved parameters on the flow, motile microbes diffusion rate, mass and heat transfer rates are examined and shown through diagrams and tables. Comparisons with graphical and tabular data are provided and observed to be in a good agreement. Numerical results evidently point out that the motile microbes parameter and the bioconvection Peclet number elevate the motile microorganisms' density whereas the thermal radiation phenomenon enhances the temperature.
| S-EPMC7773592 | biostudies-literature
Project description:Droplet evaporation on porous materials is a complex dynamic that occurs with spontaneous liquid imbibition through pores by capillary action. Here, we explore water dynamics on a porous fabric substrate with in-situ observations of X-ray and optical imaging techniques. We show how spreading and wicking lead to water imbibition through a porous substrate, enhancing the wetted surface area and consequently promoting evaporation. These sequential dynamics offer a framework to understand the alterations in the evaporation due to porosity for the particular case of fabric materials and a clue of how face masks interact with respiratory droplets.
| S-EPMC8776847 | biostudies-literature
Project description:Porous particles have found widespread applications in therapeutic diagnosis, drug delivery, and tissue engineering due to their typical properties of large surface area, extensive loading capacity, and hierarchical microstructures. Attempts in this aspect are focusing on the development of effective methods to generate functional porous particles. Herein, a simple droplet microfluidics for continuously and directly generating porous particles by introducing bubble-propelled nanomotors into the system is presented. As the nanomotors can continuously generate gas bubbles in the unsolidified droplet templates, the desirable porous microparticles can be obtained after droplet polymerization. It is demonstrated that the generation process is highly controlled and the resultant microparticles show excellent porosity and monodispersity. In addition, the obtained porous microparticles can serve as microcarriers for 3D cell culture, because of their characteristic porous structures and favorable biocompatibility. Moreover, owing to the existence of oxygen in these microparticles, they can be used to improve the healing effects of wounds in the type I diabetes rat models. These remarkable features of the generation strategy and the porous microparticles point to their potential values in various biomedical fields.
| S-EPMC8811803 | biostudies-literature
Project description:The aim of this article is to model and analyze an unsteady axisymmetric flow of non-conducting, Newtonian fluid squeezed between two circular plates passing through porous medium channel with slip boundary condition. A single fourth order nonlinear ordinary differential equation is obtained using similarity transformation. The resulting boundary value problem is solved using Homotopy Perturbation Method (HPM) and fourth order Explicit Runge Kutta Method (RK4). Convergence of HPM solution is verified by obtaining various order approximate solutions along with absolute residuals. Validity of HPM solution is confirmed by comparing analytical and numerical solutions. Furthermore, the effects of various dimensionless parameters on the longitudinal and normal velocity profiles are studied graphically.
| S-EPMC4349699 | biostudies-literature
Project description:To investigate liquid seepage process in a coal granular-type porous medium, a new sampling device was designed to obtain coal samples with required porosity. Meanwhile, an approach combining ultra-deep-field microscopy with advanced digital image processing technologies was proposed to rebuild granular-type porous medium models. The liquid seepage process was simulated with CFD, and the effects of head pressure, liquid viscosity, and pore size were studied. The results show that only liquids with head pressures above a critical value can penetrate into coal stacks and the hydraulic conductivity and permeability are positively correlated to the driving head pressure. Liquid viscosity enhances flow deformation, causing more eddy current energy dissipation; the turbulent eddy dissipation caused by acetone, methanol, and ethanol was 700, 1200, and 4700 m2/s3, respectively. Larger pores can strengthen the additional pressure at the front end of the flow, reducing the flow resistance and thus increasing the fluid kinetic energy and seepage velocity.
| S-EPMC7439363 | biostudies-literature
Project description:[This corrects the article DOI: 10.1371/journal.pone.0117368.].
| S-EPMC4395451 | biostudies-literature
Project description: Not available
| S-EPMC4408140 | biostudies-literature
Project description:Transformation mapping theory offers us great versatility to design invisible cloaks for the physical fields whose propagation equations remain invariant under coordinate transformations. Such cloaks are typically designed as a multi-layer shell with anisotropic material properties, which makes no disturbance to the external field. As a result, an observer outside the cloak cannot detect the existence of this object from the field disturbances, leading to the invisible effect in terms of field prorogation. In fact, for many prorogating fields, at a large enough distance, the field distortion caused by an object is negligible anyway; thus, a thin cloak is desirable to achieve near-field invisibility. However, a thin cloak typically requires more challenging material properties, which are difficult to realize due to the huge variation of anisotropic material parameters in a thin cloak region. For a flow field in a porous medium, by applying the bilayer cloak design method and integrating the inner layer with the obstacle, we successfully reduce the anisotropic multi-layer cloak into an isotropic single-layer cloak. By properly tailoring the permeability of the porous medium, we realize the challenging material parameters required by the ultrathin cloak and build the thinnest shell-shaped cloak of all physical fields up to now. The ratio between the cloak's thickness and its shielding region is only 0.003. The design of such an ultrathin cloak may help to achieve the near-field invisibility and concealment of objects inside a fluid environment more effectively.
| S-EPMC9190057 | biostudies-literature
Project description:The confluence of droplet-compartmentalised chemical systems and architectures composed of interacting droplets points towards a novel technology mimicking core features of the cellular architecture that dominates biology. A key challenge to achieve such a droplet technology is long-term stability in conjunction with interdroplet communication. Here, we probed the parameter space of the Belousov-Zhabotinsky (BZ) medium, an extensively studied model for non-equilibrium chemical reactions, pipetted as 2.5 mm droplets in hexadecane oil. The presence of asolectin lipids enabled the formation of arrays of contacted BZ droplets, of which the wave patterns were characterised over time. We utilised laser-cut acrylic templates with over 40 linear oil-filled slots in which arrays are formed by pipetting droplets of the desired BZ composition, enabling parallel experiments and automated image analysis. Using variations of conventional malonic acid BZ medium, wave propagation over droplet-droplet interfaces was not observed. However, a BZ medium containing both malonic acid and 1,4-cyclohexanedione was found to enable inter-droplet wave propagation. We anticipate that the chemical excitation properties of this mixed-substrate BZ medium, in combination with the droplet stability of the networks demonstrated here for nearly 400 droplets in a template-defined topology, will facilitate the development of scalable functional droplet networks.
| S-EPMC6107623 | biostudies-literature
Project description:Iontophoresis uses electricity to deliver solutes into living tissue. Often, iontophoretic ejections from micropipets into brain tissue are confined to millisecond pulses for highly localized delivery, but longer pulses are common. As hippocampal tissue has a ?-potential of approximately -22 mV, we hypothesized that, in the presence of the electric field resulting from the iontophoretic current, electroosmotic flow in the tissue would carry solutes considerably farther than diffusion alone. A steady state solution to this mass transport problem predicts a spherically symmetrical solute concentration profile with the characteristic distance of the profile depending on the ?-potential of the medium, the current density at the tip, the tip size, and the solute electrophoretic mobility and diffusion coefficient. Of course, the ?-potential of the tissue is defined by immobilized components of the extracellular matrix as well as cell-surface functional groups. As such, it cannot be changed at will. Therefore, the effect of the ?-potential of the porous medium on ejections is examined using poly(acrylamide-co-acrylic acid) hydrogels with various magnitudes of ?-potential, including that similar to hippocampal brain tissue. We demonstrated that nearly neutral fluorescent dextran (3 and 70 kD) solute penetration distance in the hydrogels and OHSCs depends on the magnitude of the applied current, solute properties, and, in the case of the hydrogels, the ?-potential of the matrix. Steady state solute ejection profiles in gels and cultures of hippocampus can be predicted semiquantitatively.
| S-EPMC3312800 | biostudies-literature