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This capsule contains the data analysis of lattice Boltzmann simulations of the structural response of bijels stabilized by magnetic ellipsoidal particles. Analysis includes the average and directional microstructure change observed after application or removal of magnetic fields. 

This capsule contains the data analysis of lattice Boltzmann simulations of the formation of bijels stabilized by magnetic ellipsoidal particles. Using data from hybrid Lattice Boltzmann-Molecular Dynamics simulations of a binary liquid with suspended magnetic ellipsoidal particles, we analyze the bond orientational order within the interfacial particle layer, the mean and Gaussian curvature of the interfaces, and the topological properties of the emulsion morphology. 

Bicontinuous interfacially jammed emulsion gels offer a versatile platform for emulsion templating of functional porous materials, including membranes, electrodes, and tissue-mimetic biomaterials. In many applications of such materials, the microstructure determines the properties and performance of devices. Characterization of the morphological structure of emulsion templates is, thus, an important step in developing fabrication methods for porous materials with tunable microstructure. We present a structural analysis of bijels stabilized by magnetic ellipsoidal particles. Using data from hybrid lattice Boltzmann-molecular dynamics simulations of binary liquids with suspended magnetic ellipsoidal particles, we analyze the bond orientational order within the interfacial particle layer, the mean and Gaussian curvature of the interfaces, and the topological properties of the emulsion morphology. The results suggests that the particle packing at the interface is influenced by the local topology as characterized by the Gaussian curvature, and the global topological properties can be linked to domain coarsening mechanisms, such as coalescence of domains and pinch-off of channels. By analyzing independent simulation runs with different initial conditions, we probe the statistical variations of different properties, including the channel size distribution and the average channel size. Our analysis provides a more detailed picture of the structural properties of bijels stabilized by magnetically responsive ellipsoids and can guide the optimization of interfacial particle packing and domain structure of particle-stabilized emulsion systems. 

This capsule contains the data analysis of lattice Boltzmann simulations of the formation of bijels stabilized by magnetic ellipsoidal particles. The analysis includes the scaling of the structure factor and domain size, and the dependence of the domain size and tortuosity on the magnetic field. The orientational order of the magnetic dipoles and the interface alignment is analylzed as well as the particle packing in the interface. 

Lattice Boltzmann simulations of bijels stabilized by ellipsoidal magnetic particles in external magnetic fields demonstrate the potential of magnetic particles for fabrication of emulsion systems with tunable, anisotropic properties. 

The properties of multicomponent fluids are governed by the interplay of phase behavior, fluid dynamics, and interfacial thermodynamics. A mixture formulation that leverages this interplay is an important aspect in many fabrication processes based on emulsion templating. The lattice Boltzmann method (LBM) has become a popular approach for simulating hydrodynamic effects in complex fluids and soft matter. Here we present an implementation of a ternary lattice Boltzmann model that allows to simulate a mixture of three immiscible fluids. We build on the LATBOLTZ extension of the open-source package LAMMPS and implement a ternary free energy model recently introduced by Semprebon et al. [Phys. Rev. E 93, 033305 (2016)]. We validate the static and dynamic properties by simulating liquid lenses, double emulsions, and ternary mixtures. From the simulations, we obtain the complete morphology diagram of the ternary mixture in composition space. We further discuss an application of the method to phase segregation of ternary films. The implementation of the ternary LBM in LAMMPS opens vast opportunities for mesoscale simulations of interfacial phenomena and non-equilibrium transport processes in multicomponent fluid mixtures. 

Abstract Filtering facepiece respirators (FFRs) provide effective protection against diseases spread through airborne infectious droplets and particles. The widespread use of FFRs during the COVID-19 pandemic has not only led to supply shortages, but the disposal of single-use facemasks also threatens the environment with a new kind of plastic pollution. While limited reuse of filtering facepiece respirators has been permitted as a crisis capacity strategy, there are currently no standard test methods available for decontamination before their repeated use. The decontamination of respirators can compromise the structural and functional integrity by reducing the filtration efficiency and breathability. Digital segmentation of X-ray microcomputed tomography (microCT) scans of the meltblown nonwoven layers of a specific N95 respirator model (Venus-4400) after treatment with one and five cycles of liquid hydrogen peroxide, ultraviolet radiation, moist heat, and aqueous soap solution enabled us to perform filtration simulations of decontaminated respirators. The computed filtration efficiencies for 0.3 µm particles agreed well with experimental measurements, and the distribution of particle penetration depths was correlated with the structural changes resulting from decontamination. The combination of X-ray microCT imaging with numerical simulations thus provides a strategy for quantitative evaluation of the effectiveness of decontamination treatments for a specific respirator model. 

Multimaterial interface reconstruction has been investigated over the years both from visualization and analytical point of view using different metrics. When focusing on visualization, interface continuity and smoothness are used to quantify interface quality. When the end goal is interface analysis, metrics closer to the physical properties of the material are preferred (e.g., curvature, tortuosity). In this paper, we re-evaluate three Multimaterial Interface Reconstruction (MIR) algorithms, already integrated in established visualization frameworks, under the lens of application-oriented metrics. Specifically, we analyze interface curvature, particle-interface distance, and medial axis-interface distance in a time-varying bijel simulation. Our analysis shows that the interface presenting the best visual qualities is not always the most useful for domain scientists when evaluating the material properties.