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A simplified analytical solution for the flow of power-law liquids through a conical annulus was derived to estimate the flow profile, wall shear rate, and elongation rate in the spinneret during the spinning of hollow fiber membranes. The velocity profiles and shear and elongation rates of the power-law fluid showed good agreement with those obtained from computational fluid dynamic simulations. Although the actual spinneret is characterized by an annulus with a converging cross section, most studies to date have used a geometrical concentric annulus for the sake of simplicity. The results of the current work indicate that neglecting the converging characteristics of the actual spinneret can lead to significant underestimation of the wall shear rate. Using the equations derived in our work, we were able to predict not only the velocity profile but also the wall shear rate and the elongation rate; the influence of the spinneret design on the membrane morphology and properties were also examined. © 2011 American Institute of Chemical Engineers AIChE J, 2012 [ABSTRACT FROM AUTHOR]

The capture of CO2 in a rotating packed bed (RPB) using highly concentrated alkanolamine solutions has been proved to be an effective way to enhance the absorption efficiency of CO2. In this investigation, the effects of alkanolamine concentration on the CO2 removal efficiency and mass transfer coefficients (KGa) at various lean CO2 loadings were studied. Monoethanolamine and 2‐methyl‐amino‐ethanol solutions were used to absorb CO2 in an RPB. Experimental results showed that increasing the alkanolamine concentration effectively enhanced the CO2 absorption efficiency of a fresh absorbent. For an absorbent with a high CO2 loading, an optimal alkanolamine concentration was observed because the viscosity of the absorbent dramatically increased at high alkanolamine concentration and high CO2 loading. A correlation of KGa was proposed and the mass transfer coefficient can be expressed as a function of the free alkanolamine concentration and the viscosity of the absorbent. [ABSTRACT FROM AUTHOR]

To achieve the modification of photonic band structures and realize the dispersion control toward functional photonic devices, composites of photonic crystal templates with high-refractive-index material are fabricated. A two-step process is used: 3D polymeric woodpile templates are fabricated by a direct laser writing method followed by chemical vapor deposition of MoS 2 . We observed red-shifts of partial bandgaps at the near-infrared region when the thickness of deposited MoS 2 films increases. A ∼10 nm red-shift of fundamental and high-order bandgap is measured after each 1 nm MoS 2 thin film deposition and confirmed by simulations and optical measurements using an angle-resolved Fourier imaging spectroscopy system., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)