• Polymer(Korea)
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• v.25 no.2
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• pp.151-160
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• 2001

Polymeric membranes consisting of poly(d,1-lactide) as a polymer matrix and crystallizable progesterone as a drug were prepared by coagulating polymeric solutions. The homogeneous casting solutions in dimethyformamide were solidified by using three different coagulating processes : solvent evaporation under vacuum, solvent extraction via immersion into the nonsolvent bath, or vapor exposure at high humidity condition. With solvent removal via evaporation under vacuum, the cast solution film was vitrified to form a homogeneous film containing progesterone of spherical shape distributed evenly in the film. Being prepared by solvent extraction via immersion into a water bath, the resulting membrane showed an asymmetric structure, with progesterone of big crystallites distributed unevenly in the structure. On the other hand, the coagulation under high humidity transformed the cast film into a sponge-like structure, where progesterone took a shape like flake.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.4
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• pp.357-363
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• 2014

The electrolyte wetting phenomena in the electrode of lithium ion battery is studied numerically using a multiphase lattice Boltzmann method (LBM). When a porous electrode is compressed during roll-pressing process, the porosity and thickness of the compressed electrode are changed, which can affect its wettability. In this study, the change in electrolyte distribution and degree of saturation as a result of varying the compression ratio are investigated with two-dimensional LBM approach. We found that changes in the electrolyte transport path are caused by a reduction in through-plane pore size and result in a decrease in the wettability of the compressed electrode.

• Membrane Journal
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• v.11 no.2
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• pp.89-95
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• 2001

Polysulfone membranes containing an inorganic fluor, cerium activated yttrium silicate (CA Y5), were prepared via the phase inversion technique. The casting solutions with the fluor' were solidified to result in a membrane by using two different nonsolvent coagulants, water and isopropanol. In the process, the fluor worked as a monitioring agent for investigating the characteristics of the phase inversiun process. On the initial contact with water as nonsolvent, the induction of rapid polymer collapse results.in the entrapment of the fluor in the formed membrane structure. Impregnated fluor is dispersed in the polymer structure rather than being enveloped by polymer molecules. In comparison, the fluor is localized in the cell-like structure of membrane, as the cast solution film is cuagulated by immersion into a isopropanol bath.

• Journal of Ocean Engineering and Technology
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• v.23 no.2
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• pp.98-103
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• 2009

The resin infusion method is the latest technology of FRP laminating and cleaning to improve FRP hull quality. This method is focused on how to arrange infusion channels for the laminiating strategy. The laminating strategy using the resin infusion method has been utilized to complete the infusion work and remove the cavities on the FRP surface within the curing time. It is resulting from the arrangement of infusion and vacuum channels, the resin property, and the combination of FRP. This strategy has been depended on the field experience for manufacturing FRP without the resin infusion simulation. This study can help to improve the efficiency of FRP fabrication with the laminating strategy including the resin infusion simulation instead of the field experience.