Journal of Asian Ceramic Societies

Sánchez Torres, Carlos Gibran; Miranda López, Martín Itzcóatl; Sereno, Hugo; Pola, Antonio

doi: 10.1080/21870764.2026.2672837pmid: N/A

This study evaluates how adding 0.2 wt% EMSIL-DRY™, a commercial low-melting burn-out polymeric multifilament fiber used to enhance permeability during dry-out, affects the pore-network evolution, thermal-gradient development, and ultrasonic integrity of ultra-low cement castables (ULCCs). Cubic specimens (6″ and 11″) were heat-treated at 350°C, 560°C, and 730°C to assess porosity evolution, thermal gradients, and integrity. Mercury intrusion porosimetry showed increased total porosity, especially intraparticle, with fiber addition. Interparticle porosity rose at intermediate temperatures due to fiber burnout but decreased at 730°C. A secondary pore network (0.1–2 μm) improved vapor release and reduced internal thermal gradients by up to 23.75% at 560°C. Despite a decrease in P-wave velocity (4120 m/s to 3880 m/s), structural integrity was preserved. Larger specimens exhibited more pronounced effects, highlighting scale-dependent behavior. Overall, fiber addition improved thermal dissipation by enhancing pore connectivity and permeability while preserving ultrasonic integrity, offering practical insights for optimizing refractory castables in high-temperature industrial environments.

Iwabuchi, Naoki; Simba, Daigo; Kanai, Toshimitsu

doi: 10.1080/21870764.2026.2680785pmid: N/A

Silica microparticles are widely used in various fields, including chromatography, catalysis, and drug delivery systems, owing to their excellent intrinsic properties and micrometer-scale. To improve product quality and reproducibility, it is necessary to develop a preparation method for monodisperse silica microparticles with tunable size. Although monodisperse silica microparticles can be prepared using microfluidic devices, silica gel tends to form in premixed reaction precursor solutions over time, leading to clogging of the flow channels. This paper reports a preparation method for monodisperse silica microparticles across a wide size range while mitigating channel clogging. Specifically, monodisperse droplets of an aqueous sodium silicate solution were generated using a microfluidic device and subsequently reacted with an aqueous sodium bicarbonate solution outside the device. By adjusting the flow channel dimensions, gas pressure for the aqueous phase flow, and oil phase flow rate, monodisperse silica microparticles were successfully prepared over a size range spanning two-orders-of-magnitude.