• Journal of the Korean Society for Heat Treatment
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• v.14 no.4
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• pp.205-211
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• 2001

The characteristics of super duplex stainless steel were investigated on its fibrous structure and dispersed structure. These structures consist of various volume fractions and distributions of the austenite phase that were obtained by changing the heat treatment temperature and cycle. The fibrous structure had higher austenite volume fraction than dispersed structure on the same temperature. As the austenite volume fraction increased in both structures, tensile strength and elongation increased, but hardness decreased. Fatigue life of fibrous structure parallel to rolling direction was shorter than that of perpendicular to rolling direction. Fatigue life of dispersed structure was longer than parallel fibrous structure, and shorter than perpendicular fibrous structure. Fatigue crack propagation rate of fibrous structure was faster than that of dispersed structure.

• Journal of the Korean Ceramic Society
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• v.34 no.7
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• pp.758-766
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• 1997

Non-brittle fracture behaviour of the two composite structures made of two different brittle materials was investigated using 3-point bending test. First, the layered and fibrous macro-composites were fabricated using the material easily formed, yet showing a brittle fracture behaviour similar to ceramics. The layered and fibrous Al2O3 /Al2O3 composites with weak interface were also fabricated using plate of 2 mm thickness and rod of 3 mm diameter respectively. Comparison of the mechanical properties between these two structures was performed in the lights of flexural strength and work of fracture for the composites consisting of Al2O3 and simulated materials respectively. The strength ratio of layered structure to the monolith of same volume was 0.6 and the ratio of fibrous one was about 0.2 for the composites made of simulated brittle material. The ratio of the work of fracture of the fibrous to the layered was 0.47. For Al2O3/Al2O3 composites, the strength ratio of layered and fibrous structures to the monolith with same volume were about 0.6 and 0.2 respectively. The ratio of work of fracture of the fibrous to the layered was 0.6. These confirmed that the layered structure was superior to the fibrous one in terms of flexural strength and work of fracture.

• Imaging Science in Dentistry
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• v.41 no.1
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• pp.23-28
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• 2011

Purpose : This study was to find the computed tomographic features of fibrous dysplasia of the maxillofacial region. Materials and Methods : All eight cases included in the study reported either to Government Dental College and Hospital or Nair Hospital Dental College, Mumbai between 2003 and 2009. The patients were prescribed computed tomogram in addition to conventional radiographs of maxillofacial region which were studied for characteristic features of fibrous dysplasia. The diagnosis of fibrous dysplasia was confirmed by histopathological report. Results : All cases showed the ill-defined margins of lesions except in the region where the lesions were extending to cortex of the involved bone. Internal structure of all cases showed ground glass appearance. Four cases of maxillary lesion showed the displacement of maxillary sinus maintaining the shape of maxillary sinus. Two cases showed complete obliteration of maxillary sinus. Displacement of inferior alveolar canal did not follow any typical pattern in any of the cases but was displaced in different directions. Conclusion : The craniofacial type of fibrous dysplasia is as common as fibrous dysplasia of jaw. The margins, extent, internal structure and effect on surrounding structure are well detected on computed tomographic images.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.5
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• pp.311-325
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• 2001

Tissue engineering scaffolds play a critical role in regulating the reconstructed human tissue development. Various types of scaffolds have been developed in recent years, including fibrous matrix and foam-like scaffolds. The design of scaffold materials has been investigated extensively. However, the design of physical structure of the scaffold, especially fibrous matrices, has not received much attention. This paper compares the different characteristics of fibrous and foam-like scaffolds, and reviews regulatory roles of important scaffold properties, including surface geometry, scaffold configuration, pore structure, mechanical property and bioactivity. Tissue regeneration, cell organization, proliferation and differentiation under different microstructures were evaluated. The importance of proper scaffold selection and design is further discussed with the examples of bone tissue engineering and stem cell tissue engineering. This review addresses the importance of scaffold microstructure and provides insights in designing appropriate scaffold structure for different applications of tissue engineering.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.65-69
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• 2002

An Al film deposited on the Kovar alloy substrate was anodically-bonded to the borosilicate glass, and the bond interfaces was closely investigated by transmission electron microscopy. Al oxide was found to form a layer ~l0 nm thick at the bond interface, and fibrous structure of the same oxide was found to grow epitaxially in the glass from the oxide layer. The fibrous structure grew with the bonding time. The mechanism of the formation of this fibrous structure is proposed on the basis of the migration of Al ions under the electric field. Penetration of Al into glass beyond the interfacial Al oxide was not detected. The comparison of the amount of excess oxygen ions generated in the alkali depletion layer with that incorporated in the Al oxide suggests that the growth of the alkali-ion depletion layer is controlled by the consumption of excess oxygen to form the interfacial Al oxide.

• Tribology and Lubricants
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• v.11 no.2
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• pp.8-14
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• 1995

The filtration of the magnetic fibrous polymeric filter with packing density profile made of a self-bonded, nonwoven structure comprising a thermoplastic polymer and a magnetic substance was investigated using an oil filter tester, a particle quantifier and an image analyzer system. The magnetic fibrous polymeric filter showed excellent filtration efficiency compared with conventional paper filter. From the experimental results, It is deduced that the filtration mechanism of conventional paper filter is only the function of physical porosity by surface filteration. On the other hand, the newly magnetic fibrous polymeric filter is designed with a new concept in filtration mechanism. That is, it has a dual function of depth and magnetic filters by physical porosity and magnetic attraction. The newly magnetic fibrous polymeric filter has been shown to be a highly effective oil filter for lubrication systems.

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2295-2298
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• 2012

We describe herein a three-dimensionally diverse micropatterning of poly(lactic acid), as a biopolymer, using 1-butyl-3-methylimidazolium-based room-temperature ionic liquids (bmim-based RTILs), [bmim]X (X = $SbF_6$, $PF_6$, $NTf_2$, Cl). Utilizing the hydrophobic bmim-based RTILs, [bmim]X (X = $SbF_6$, $PF_6$, $NTf_2$) and a phase separation technique, we were able to produce white and opaque membranes with a three-dimensional structure closely packed with particles ($10-50{\mu}m$ in diameter). The particlulate structure, made by the assistance of [bmim]$NTf_2$ and DCM, interestingly transformed to a fibrous structure by using a cosolvent, e.g., DCM/$CF_3CH_2OH$. When we used an increased amount of [bmim]$NTf_2$, the particles were effectively detached and macrosized ($100-500{\mu}m$ in diameter) and the oval-shaped beads were obtained in a powder form. By varying the counter-anion type of the imidazolium-based RTIL, for example from $NTf_2^-$ to $Cl^-$, the particulate 3D-morphology was once more transformed to a porous structure. These reserch results could be potentially useful, as a method to fabricate particulate scaffolds, fibrous or porous scaffolds, and beads as a biopolymer device in diverse fields including drug delivery, tissue regeneration, and biomedical engineering.

• Journal of Ocean Engineering and Technology
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• v.17 no.2
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• pp.40-46
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• 2003

The corrosion resistance of super duplex stainless steel on both its fibrous and dispersed phase was investigated. These structures consist of various volume fraction and distribution of austenite structure, which were obtained by changing the heat treatment temperature and cycle. The fibrous phase had higher austenite volume fraction than that of the dispersed phase at the same temperature. Corrosion resistance of super duplex stainless steel was evaluated through an immersion test and an impingement test, using 35% HCI and sea water, respectively. Super duplex stainless steel was compared with STS316L and STS304. The corrosion resistance of super duplex stainless steel was superior to ST316L and STS304. The dispersed phase of super duplex stainless steel was more stabilized than the fibrous phase in corrosion. The magnitude of corrosion rate was in order STS304, STS316L, fibrous phase of super duplex stainless steel and dispersed phase of super duplex stainless steel.

• Journal of International Society for Simulation Surgery
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• v.3 no.2
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• pp.60-63
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• 2016

Fibrous dysplasia is quite a rare disease usually involving maxilla and mandible. Because of its benign clinical course, conservative contouring surgery has been recommended for facial deformity. 3D rapid prototype (RP) model gives a lot of informations before operation such as depth of drilling, area of resection and important anatomic structure. The purpose of this study was to report maxilla-mandibular contouring surgery in fibrous dysplasia patients. A total of 14 consecutive patients were included for surgical and esthetic evaluation. Among 14 patients, RP model study was performed in two patients with severe facial deformity. The other patients underwent contouring surgery under conventional methods. Surgical evaluation was performed with computed tomography scan before and after operation. Surgical resection was successful and patients were satisfied with the surgical results.

• Journal of the Korean Ceramic Society
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• v.54 no.6
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• pp.499-505
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• 2017

Flexible silicon carbide fibrous mats were fabricated by a combination of electrospinning and a polymer-derived ceramics route. Polycarbosilane was used as a solute with various solvent mixtures, such as toluene and dimethylformamide. The electrospun PCS fibrous mats were cured under a halogen vapor atmosphere and heat treated at $1300^{\circ}C$. The structure, fiber morphology, thermal behavior, and crystallization of the fabricated SiC fibrous mats were analyzed via scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermal imaging. The prepared SiC fibrous mats were composed of randomly distributed fibers approximately $3{\mu}m$ in diameter. The heat radiation of the SiC fiber mats reached $1600^{\circ}C$ under microwave radiation at a frequency of 2.45 GHz.