• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.4
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• pp.340-349
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• 2007

Free flap transplantation with microvascular anastomosis has been successfully performed by development of surgical technique, materials and postoperative monitoring equipments of flap. But success rate of microvascular anastomosis is influenced by various factors, and failure rate is about 5-10%. The most influential factor for success rate is surgical technique and other factors that influence failure of microvascular anastomosis are ischemic time of free flap, thrombus formation of anastomosis region and vascular spasm. In this study, vascular patency and thrombus formation in experimental micro-venous anastomosis, and endothelial repair were observed with histologic analysis, scanning electron microscopy, transmission electron microscopic examination. The results were obtained as follows: 1. In vascular patency test in 30 minute and 7 days after micro-venous anastomosis with heparin irrigation, all of 12 anastomosis site were good vascular patency. 2. In thrombus formation in 2 weeks group(Experimental I), 2 site of 6 cases were observed thrombus, and in 4 weeks group(Experimental II), 1 site of 6 cases were observed thrombus. 3. In histologic examination, normal vein(Control Group) showed continued internal elastic lamina, well formed thick smooth muscle layer and connective tissue. The group of 2 weeks after microvenous anastomosis(Experimental I) showd locally recovered internal lamina, discontinued internal lamina, disorganized smooth muscle cells and granulation tissue around suture silk. In the group of 4 weeks after micro-venous anastomosis(Experimental II), anastomosis site showed almostly continued internal lamina, disorganized smooth muscle cells and cicartrized tissue around suture silk. 4. In scanning electron microscope examination in 2 weeks(Experimental I) after micro-venous anastomosis, mesh fibrin formation showed near to endothelial cells, and in 4 weeks after micro-venous anastomosis(EXperimental II), numerous blood cells and fibrin mesh formation was seen associated with irregular endothelial cell arrangement. 5. In transmission electron microscope examination in 2 weeks after micro-venous anastomosis(Experimental I), irregular arrangement of smooth muscle cells was seen adjacent to collagenized tissue around suture silk. In 4 weeks after micro-venous anastomosis(Experimental II), denuded venous wall composed of relatively well arranged smooth muscle cells was covered by endothelial cells, but fibroblast cells and foreign body giant cells near to suture silk was remained. From the results obtained in this study, results of good vascular patiency and anti-thrombotic effect of heparin were obtained as a local irrigation solution, and repair of venous endothelial cell was observed in 2 weeks after micro-venous anastomosis.

• Journal of Sericultural and Entomological Science
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• v.29 no.2
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• pp.67-72
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• 1987

This study was carried out for the optimum predegumming in the protease degumming process of silk fabrics by ocmparing the physical properties of silk fabrics degummed with different weight losses of predegumming. 1. In twill habutai, the stiffness of fabric was reduced and the smoothness was improved with increasing weight loss of predegmming, however, the soft feeling value which means the total handle value of medium fabric for lady, was maximum at 20% of predegumming weight loss. 2. In the case of crepe de chine representing thin fabric for lady, the anti-drape stiffness was relatively increased with 22% weight loss of predegumming. However, the other physical properties, such as the flexibility with soft feeling were less related to the degrees of predegumming.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.1
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• pp.124-132
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• 2002

Dyeing properties of silk fabric on gromwell roof colorants were studied for the effect of dyeing conditions, such as methanol ratio, colorants concentration, pH, temperature and time etc. on the dye uptake and effect of mordants and mordanting methods on color change and dye uptake. And various colorfastnesses of dyed fabrics were evaluated far practical use. Gromwell colorants showed high affinity to silk and its isotherm adsorption curve was Freundlich type close to Nernst type. Therefore, it is considered that hydrogen bonding and Van der Waals force were involved in the adsorption of cromwell colorants to silk fabric. Post-mordanting method gave higher K/S value than other methods, but it was not significantly different color values from unmordanted one. Gromwell colorants produced mainly R and RP color depending on mordants and mordanting method. Dyed fabrics showed high colorfastness irrespective of mordanting treatment. Light colorfastness was increased for repeatedly dyed and Fe mordanted dyed fabrics.

• Korean Journal of Human Ecology
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• v.19 no.4
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• pp.709-717
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• 2010

This study investigated the properties and functions of wool and silk dyed with Catechu by examining the effects of dying conditions such as dye concentration, dying temperature, dyeing time, pH level and pre-mordants. These conditions were examined in relation to dye uptake and color changes, washing fastness, light fastness, ultraviolet-cut ability and antimicrobial ability of the dyed fabrics. Catechu showed good affinity to silk fiber. Langmuir adsorption isotherm was obtained, and so it was considered that ionic bondings are formed between Catechu and protein fiber. As the dyeing time and temperature is increased, the dyeability of both silk and wool fabrics also increases. At high temperatures the color of dyed fabrics changes from Y and YR to R. Wool is effective in using Al, Cu, Fe mordant, while silk is effective only in using only Cu mordants. The dyeability was shown to be improved at low pH levels. Additionally, both washing fastness and light fastness were shown to be low. However, the fabric color gradually changed to red was due to mailard reaction of catechol tannin causingby repeated washing and sunlight. The ultraviolet-cut ability was improved for cotton fabric dyed with Catechu. Also, dyed fabric with Catechu showed very good antimicrobial abilities at 99.9%.

• Journal of Sericultural and Entomological Science
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• v.37 no.1
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• pp.33-38
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• 1995

The mechanical properties and structure of degummed silk fiber stretched after being treated with 8M LiBr aqueous solution were investigated. The mechanical properties of degummed silk fiber were depended upon the treatment temperature of 8M LiBr aqueous solution. That is, the strength and elongation had a tendancy to increase with the temperature, whereas the Young's modulus tended to decrease. The X-ray diffraction pattern showed that the crystalline orientation was disordered by 8$0^{\circ}C$ treatment neverthless destruction of the crystallites did not occur. rho silk fiber could be successfully stretched up 160% under the condition of 8M LiBr aqueous solution at 80 * after immersed for 1hr. For the highly stretched sample(160%), the tensile strength and Young's modulus were significantly improved in spite of lower elongation at break. According to the examination of X-ray diffraction pattern and SEM, the orientation tends to be occured more and more with stretching ratio. From the DSC thermograms, it shows that the thermal decomposition behavior was different between untreated and treated specimen with 8M LiBr aqueous solution. The maximun endothermic peak of thermal decomposition tends to increase to high temperature with the increase of stretching ratio.

• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.180-185
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• 1996

Biosynthesis tracing of the silk fibroin in Bombyx mori silkworm was examined in vivo with isotopic [1-13C] Gly. labeling by nuclear magnetic resonance method. The [1-13C] Gly. labeled silk fibroin yielded very sharp 13C NMR signal in the posterior silk gland as well as in aqueous solution and the amound of [1-13C] Gly. labeled signal in the silkworm increased gradually and rapidly to 5-th day of fifth instar. However, the decomposition or decrease of the [1-13C] Gly. labeled signal occured from 5-th to 9-th day of fifth instar unexpectedly. These findings suggest that a relative amount of ${\alpha}$-helical portion or amorphous silk II portion was formed without any further signal from 6-th day of fifth instar to pupation. Through peak separation of orientation spectrum, between the fiber axis and the molecular bond direction, N-H bond in Bombyx mori silk fiber as well as the orientation distribution around the silk fibroin axis were determined and two kinds of peaks were also obtained from this orientation spectrum.

• Korean Chemical Engineering Research
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• v.51 no.3
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• pp.330-334
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• 2013

Mixtures of poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) and silica nanoparticles are coated on the surface of a silk fabrics separator. The coated separators are finally prepared by injecting an electrolyte solution and then characterized for use of lithium-ion battery separator/electrolyte. In the preparation, various contents of dibutylphthalate (DBP) as a plasticizer are used to enhance the formation of micropores within the coated membrane. The coated silk fabrics separators are characterized in terms of ionic conductivity, drenching rate, and electrochemical stability, and the charge-discharge profiles of lithium-ion batteries adopting the coated separators are also examined. As a result, the coated silk fabrics separator prepared using DBP 40~50 wt% and silica shows the superior separator properties and high-rate capability. This is due to (i) high sustainability of silk fabrics, (ii) the formation of micropores with the coated layer membrane by DBP, (iii) increase in drenching rate by silica nanoparticles to involve great enhancements in specific surface area and ionic conductivity.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.111-114
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• 2002

실크는 우수한 광택, 촉감, 물성을 바탕으로 하여 인류에 있어 최고의 의류용 섬유로서 널리 이용되어 왔으며 최근에는 생체적합성 등을 활용한 의료용 및 생물공학용 소재로서 응용하고자 하는 연구가 활발하게 진행중이다[1-2]. 그러나 실크는 합성섬유와는 달리 누에가 토사하는 그 순간에 그 구조 및 형태가 결정되어 고정되는 단점을 안고 있어 다양한 특성이 요구되는 의류용 및 산업용 분야로의 응용에 한계가 있다. (중략)

• 한국생활과학회:학술대회논문집
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• 2010.05a
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• pp.107-108
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• 2010

• Proceedings of the Korean Society of Soil Zoology Conference
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• 1997.03a
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• pp.2-4
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• 1997

This report includes 4 Part. I the characteristic of chinese Arachnological research; II, Systematic studies on Araneae we made in resent years; III. The survey of ecological study of Chinese Arachnology ; IV. Biocemical study of the venom and silk proteins of spiders.