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Son J.S.,Korea Textile Development Institute | Jang S.H.,Korea Textile Development Institute | Kwon T.-Y.,Kyungpook National University | Kim K.-H.,Kyungpook National University | And 2 more authors.
Materials Letters | Year: 2014

This paper studied the production and properties of bioceramics bone graft substitutes from duck beak bone, as a natural source. Duck beak bone particles were fabricated by de-fatting, followed by heat-treatment at 1000 C for 3 h in an air atmosphere. It was confirmed that heat-treated beak bone particles were highly porous in their structure, with a rough surface, and the Ca/P atomic ratio value was 1.65, similar to that of human bone. In addition, the heat-treatment process of beak bone particles resulted in single phase hydroxyapatite (HA) with high crystallinity. In vivo performance of beak bone particles using rat calvarial defects showed a significantly higher bone volume than that of bovine bone particles at 4 weeks post implantation. This study demonstrated that duck beak bones can be prepared as economical bone graft substitutes of natural, biological origin HA. © 2014 Elsevier B.V. Source

Kim S.-J.,Yeungnam University | Shim S.-B.,Korea Textile Development Institute
Fibers and Polymers | Year: 2010

This paper is aiming to develop high shrinkable differential shrinkage and mixed fibre nylon composite yarns by applying the high shrinkable polyester manufacturing technology. The wet and dry thermal shrinkages and mechanical properties of developed nylon composite yarns are measured and discussed with processing factors in the spinning and texturing processes. And the effects of the processing factors on the physical properties of high shrinkable nylon composite yarns are investigated. For this purpose, twenty seven nylon 30d/12f SDY were prepared with variation of spinning temperature, 2nd godet roller temperature and draw ratio on the spinning machine. The optimum spinning condition which showed maximum wet thermal shrinkage and stress was determined and high shrinkable nylon 30d/12f SDY spun under this optimum condition used as a core and three kinds of regular nylon filaments used as sheath were processed on the texturing machine with variation of 1st and 2nd heater temperatures. The optimum texturing process condition was decided through analysis of dry thermal shrinkage of these core and sheath nylon filaments. Finally, high shrinkable differential shrinkage and mixed fibre nylon composite yarns were made under the optimum texturing condition on the texturing machine, its wet thermal shrinkage was 13. 8 %, which was much more higher than that of regular nylon composite yarns. The differential shrinkage effect of the developed nylon composite yarns was found in the yarn surface and cross section profiles by microscope and SEM. © 2009 The Korean Fiber Society and Springer Netherlands. Source

Lee M.-H.,Kyungpook National University | Min B.K.,Yeungnam University | Son J.S.,Korea Textile Development Institute | Kwon T.-Y.,Kyungpook National University
Materials | Year: 2016

This in vitro study investigated whether different storage conditions of plasma-treated zirconia specimens affect the shear bond strength of veneering porcelain. Zirconia plates were treated with a non-thermal atmospheric argon plasma (200 W, 600 s). Porcelain veneering (2.38 mm in diameter) was performed immediately (P-I) or after 24 h storage in water (P-W) or air (P-A) on the treated surfaces (n = 10). Untreated plates were used as the control. Each group was further divided into two subgroups according to the application of a ceramic liner. All veneered specimens underwent a shear bond strength (SBS) test. In the X-ray photoelectron spectroscopy (XPS) analysis, the oxygen/carbon ratios of the plasma-treated groups increased in comparison with those of the control group. When a liner was not used, the three plasma-treated groups showed significantly higher SBS values than the control group (p < 0.001), although group P-A exhibited a significantly lower value than the other two groups (p < 0.05). The liner application negatively affected bonding in groups P-I and P-W (p < 0.05). When the veneering step was delayed after plasma treatment of zirconia, storage of the specimens in water was effective in maintaining the cleaned surfaces for optimal bonding with the veneering porcelain. © 2015 by the authors. Source

Go A.,Chonnam National University | Eun Kim S.,Chonnam National University | Mi Shim K.,Chonnam National University | Lee S.-M.,Chonbuk National University | And 3 more authors.
Journal of Biomedical Materials Research - Part A | Year: 2014

The current study was designed to investigate the chemical and physical properties of porcine-derived xenografts of different crystallinity (low and high) and to evaluate their osteogenic potential. Porcine femur bone underwent a heat treatment process at 400°C (P400) and 1200°C (P1200) and was then milled into particles of 1 mm or less. In X-ray diffraction, P400 exhibited a low crystallinity compared with that of P1200, as indicated by the relatively wide diffraction peaks. Brunauer-Emmett-Teller analysis revealed that P400 also had a wider surface area than P1200. In micro-CT scan analysis of specimens in a rat calvarial defect model, bone mineral density of the P400 group was significantly higher than that of the P1200 group (p < 0.01). New bone formation was also remarkably higher at 8 weeks in the P400 group, which showed more new osteocytes in the lacuna compared with the P1200 group. In this study, low crystalline bone particles were obtained at low processing temperature (at temperature of 400°C) and achieved superior new bone formation compared with the high crystalline bone particles created at a higher process temperature (1200°C). It can be concluded that lower process temperature bone particles might provide a more effective graft material for enhancing bone formation. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3609-3617, 2014. © 2013 Wiley Periodicals, Inc. Source

Lim S.K.,Daegu Gyeongbuk Institute of Science and Technology | Hong S.H.,Daegu Gyeongbuk Institute of Science and Technology | Hwang S.-H.,Daegu Gyeongbuk Institute of Science and Technology | Kim S.,Daegu Gyeongbuk Institute of Science and Technology | And 2 more authors.
Textile Research Journal | Year: 2012

Gold, silver, and platinum nanoparticles were immobilized on the surface of TiO2 in the sheath part of bi-component filaments. The processes involved include the spinning process used to prepare polyethylene terephthalate (PET)/PET-TiO2 bi-component filaments and the photocatalytic deposition process of gold, silver and platinum nanoparticles. The core part and the sheath part consist of virgin PET and 4 wt.% of TiO2 compounded PET, respectively. The sheath: core ratio of the filament was 50:50. For the photo-deposition of metal nanoparticles, adsorption of the metal ions on the surface of the fabrics was performed by immersing them in AgNO3, HAuCl4, and H2PtCl6 aqueous solutions, with simultaneous addition of methanol as a sacrificial agent. Photo-deposition was then carried out under UV light with an irradiation time of 60 seconds. The structural and antibacterial properties of the bi-component filaments were characterized. The nano-sized noble metal particles in a polka dot form were observed around the surface of the TiO2 particles in sheath region of bi-component filaments after photocatalytic deposition. Ag, Au, and Pt metal photo-deposited fabrics showed excellent antimicrobial effect against the two types of bacteria Staphylococcus aureus and Klebsiella pneumoniae under dark conditions. © The Author(s) 2012 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav. Source

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