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Sawade, E.;Irie, S.;Sasaki, T.;Sakurai, K.
- Proceedings of the Korean Fiber Society Conference
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- 2003.10a
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- pp.97-97
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- 2003
Recently, attention has been paid to biodegradable polymers in relation to the global environment. Poly-lactide (PLA) is one of such polymers and has studied by some investigators. In this study, the changes of crystal structure, crystal orientation and supermolecular structure of Poly(L-lactide) (PLLA) during drawing or annealing have been investigated.
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Park, S.;Kim, K.;Kwak, H.S.
- Journal of computational fluids engineering
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- v.21 no.4
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- pp.11-18
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- 2016
A numerical study is conducted on the optical fiber coating flow in a primary coating nozzle consisting of three major parts: a resin chamber, a contraction and a coating die of small diameter. The flow is driven by the optical fiber penetrating the center of the nozzle at a high speed. The axisymmetric two-dimensional flow and heat transfer induced by viscous heating are examined based on the laminar flow assumption. Numerical experiments are performed with varying the convergent angle of nozzle contraction and the optical fiber drawing speed. The numerical results show that for high drawing speed greater than 30 m/s, there is a transition in the essential flow features depending on the convergent angle. For a large convergent angle greater than $30^{\circ}$, unfavorable multicellular flow structures are monitored, which could be associated with wall boundary-layer separation. In the regime of small convergent angle, as the angle increases, the highest resin temperature at the exit of die and the coating thickness decrease but the sensitivity of coating thickness on drawing speed and the maximum shear strain of resin on the optical fiber increase. The effects of the convergent angle are discussed in view of compromise searching for an appropriate angle for high-speed optical fiber coating.
https://doi.org/10.6112/kscfe.2016.21.4.011 인용 PDF KSCI

Cheon, Cheol;Kim, Seong-Ju
- Journal of the Korean Wood Science and Technology
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- v.26 no.1
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- pp.51-56
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- 1998
The bast fiber of paper bush misumada have been cultivated in south coast bay of the Korean peninsula were not used to handmade painting paper. Therefore, in using the bast fiber of paper bush misumada manufactured handmade painting paper, tested absorption speed, blot characteristics and organic functions. The results are summarized as follows; The handmade painting paper manufacured only the bast fiber of paper bush misumada proper to the absorption speed of China ink, didn't have difference of the length and width for blot. And it was most fitted to east writing-and-painting using. Also the flexibility excell, and light and shade in overpainting directly appeared, and fitted to black-and-white drawing. And the using increase plan of the paper bush misumada demanded.
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