• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.160-167
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• 1996

The middle silk gland, that is a liquid silk thread gland consisting of silk protein, was taken out and a silk monofilament was made by drawing rapidly to approximately 3 times. In order to deteriorate the inter molecular hydrogen bonding force and to stretch in, the drawn silk filament was swoolen in boiling water. The results obtained are as follows ; The silk gland sample that just dried silk gland was occupied in crystalline region of silk-I type and random amorphous region. According to the examination of X-ray diffraction and thermal analysis, silk-II type crystal begins to appear partially in monofilament sample and spread to almost complet silk-II type crystal in 65.2% drawn sample. And, orientation of silk fibroin mlecule increased suddenly in early stage with a rise of drawing ratiofrom birefringence and density, and it was found that orientation of fibroin molecule was completed. As drawing ratio increases relation with time of hydrolysis, birefringence appeared almost fixed a tendency. Crystallization collapse by hydrolysis was not found in X-ray diffraction and thermal analysis. But, amorphous region began to flow by treated hydrolysis, that orientation of crystallization part was disturbed was supposed.

• Radiation Oncology Journal
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• v.10 no.1
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• pp.77-83
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• 1992

The incidence of malignant schwannoma in the head and neck is extremely rare. Most tumors appear as a rapidly expanding nonpainful mass and the symptoms are usually attributable to local expansion of the mass. About one half occurs in association with von Recklinghausen's disease. Wide surgical excision is generally recommended as a primary treatment. Recently, there has been a trend to include postoperative radiation therapy as a primary modality. Prognosis of head and neck malignant schwannoma has been reported as particularly poor, However, recent authors advocate that prolonged survival is possible after adequate therapy including postoperative radiation therapy. We present our experience with these tumors on very rare locations such as the ethmoid sinus and the larynx, with the review of literatures.

• Membrane Journal
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• v.18 no.2
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• pp.124-131
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• 2008

The biodegradable hyaluronic acid membranes cross-linked with lactide using the crosslinking agent, 1,3-butadiene diepoxide (BD), were prepared as a potential biocompatible material for tissue engineering. The degree of lactide and BD reaction of the crosslinked membrane was determined by the analysis of nuclear magnetic resonance spectroscopy 6% of growth inhibition was observed in case of high BD concentration but the value is low enough not to affect cell growth. As the crosslinking reaction temperature increased, elongation increased and swelling ratio decreased. The rate of degradation was found to increase with the crosslinking temperature. The drug release experiment showed that the transport of drug through the membrane decreased with the crosslinking temperature.

• Membrane Journal
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• v.11 no.1
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• pp.22-28
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• 2001

Various charged homogeneous membranes were fabricated by blending of ionic polymer with a non-ionic polymer with different ratios. In this study. sodium alginate, chitosan and poly(vinyl alcohol) were employed as anionic. cationic and non-ionic polymers, respectively. The permcation and separation behaviors of aquCOll::; salt solutions have been investigated through the charged membranes. As the content of ionic polymer increases in the membrane, the hydrophilicity of the membrane increases and pure water flux as well as solution flux increases correspondingly, indicating that the permeation performance through the membrane is cletemunecl mainly by its hydrophilicity-, Electrostatic interaction between the charged membrane and ionic solute molecules, that is. Donnan exclusion was observed to be attributed to salt rejection to a great deal of extent, and molecular sieve mechanism was effective [or the separation of the salt solution under a similar electrostatic circumstance of solutes.

• Applied Biological Chemistry
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• v.42 no.2
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• pp.91-98
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• 1999

To select the desirable soybean cultivar for chonggugjang processing, the physicochemical characteristics of raw soybean materials and chonggugjang samples were investigated. Eight soybean varieties including Danyeobkong, Danbaegkong, Kwanankong, Pureunkong, Manlikong, Sinpaldalkong 2, Jinpeumkong and Hwankeumkong were used for experiment. On the basis of quality characteristics of raw materials, such as seed coat weight rate, hydration swelling, and the content of fructose, glucose and sucrose, and chonggugjang, such as hardness, ${\gamma}-glutamyltranspeptidase\;({\gamma}-GTP)$ activity, free amino acid content, and amino type nitrogen content, Sinpaldakong 2 and Danyeobkong were desirable soybean cultivars for high quality chonggugjang processing.

• Polymer(Korea)
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• v.24 no.5
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• pp.621-628
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• 2000

Microporous polypropylene (PP) membranes have the high chemical and corrosion resistance, the good mechanical properties and the thermal stability under high temperatures, but its application is restricted within narrow limits due to hydrophobicity of membranes. In order to impart permanent hydrophilicity to the PP microfiltration membrane, the radiation-induced graft of 2-hydroxyethyl methacrylate (HEMA) and acrylic acid (AAc) containing hydrophilic functional group onto the membrane has been studied. The effect of graft conditions such as reaction time, total radiation dose, reaction temperatures, acid compositions on graft yield was investigated. Modified PP membranes were shown to cause an increase in the gas flux. Oil emulsion permeation flux of both original PP membrane and modified PP membrane was examined.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.11a
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• pp.61-61
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• 2011

비스코스 레이온(Viscose Rayon)은 목재 펄프를 원료로 한 재생섬유로서 은은한 광택과 발색성, 흡습성 등의 기능 뿐만 아니라, 천연섬유에 찾을 수 없는 Numeri감(Smoothness), Drape(처짐)성, 반발탄성을 가지고 있는 지극히 친환경적이며 자연순환형 소재로 인식, 지구온난화에 따른 CoolBiz Look 패션소재인 레이온 소재에 관심이 증대되고 있다. 한편, 레이온 소재는 수분흡수 시 강도저하, 수축과 구김, 염색 불균염 등의 문제점과 섬유공정상 생활취급상에 많은 애로를 가지고 있으며, 구성고분자가 수소결합에 의해 강고하여 "신축문제", 수분흡수시 팽윤(Swelling)에 의한 형태불안, 즉 "수축문제"가 개선해야 할 고질적 문제로 남아 있다. 또한, 습식방사에 따른 분자구조적 불안정성으로 건 습열처리시 형태불안정(치수변화율이 큼)으로 제직(준비) 및 후공정상 여러 가지 Trouble 유발과 완제품 세탁시 수축발생으로 종종 Dry Creanning해야 하는 문제점들이 내재되어 있다. 따라서 본 연구에서는 레이온 소재의 형태안정화 제품을 개발하기 위하여 복합사가공 및 염색가공 기술을 개발하고자 하며, 신축 및 복합기술에 의한 Rayon DTY, T/R 신축 및 복합기술에 의한 Rayon DTY, T/R 복합가공사를 개발, 제편직 요소기술과 최적의 전처리 조건, 다양한 염료의 종류, 염색온도 조건 등에 관한 연구를 진행하였다.

• Polymer(Korea)
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• v.29 no.1
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• pp.91-95
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• 2005

The PVA hydrogels were prepared by the chemical and irradiation method to improve the heat resistance of these hydrogels at the high temperature. The physical properties such as the gel content, the degree of swelling and the gel strength for the synthesized hydrogels were examined. Gel content increased as the chemical reaction time and the irradiation dose increased, and gel content of the hydrogels were higher when the two-steps of chemical and irradiation method were used rather than only the chemical method. Gel strength increased as the chemical reaction time increased, and as the irradiation dose decreased. The hydrogels prepared by the chemical reaction for 5 hours and the two-steps had the heat resistance at the high temperature.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.301-306
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• 1997

This study is presented to investigate the physico-chemical properties and qualities for the starch isogenic lines bred in barley(Hordeum vulgare L.).The pearling yield showed higher value in Franubet and Wafranubet than others, but the whiteness of pearled barley varied with the cultivars. The milling rate showed excellence in Franubet, fractured granular lines, whereas that of the waxy and round endosperm isogenic lines is poor. Franubet, the lines having fractures starch granule, was highest in starch content. The highest value in swelling power and water-binding capacity of the barley was proved by the lines having waxy and fractured starch endosperms. The amylogram patterns indicated that the waxy lines such as Wanubet and Wafranubet have lower initial gelatinization temperature and higher maximum viscosity than those of the normal lines. ${\beta}-Glucan\;viscosity$ was generally higher in waxy barley but changed greatly with the cultivars. The water absorption, soluble solid and expansibility in cooking property showed the highest value in waxy and fractured starch granular lines, and the whiteness of cooked barley did not differ with cultivars.

• Polymer(Korea)
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• v.33 no.5
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• pp.463-468
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• 2009

Syntheses of monodisperse and micron-sized hollow plastic pigment (HPP) were carried out through the core-shell reaction. The effects of the reaction parameters, such as the particle size, molecular weight, the swelling time, agitation rate, and the solid contect were investigated. This micron-sized HPP could be made by using the alkali soluble core with at least bigger than 200 nm size. To obtain a higher opacity ratio, the swelling time and molecular weight of the core should be controlled. The agitation rate affected the particle's morphology. To prevent the shell destruction, the agitation rate must be sufficiently low in case of the syntheses of micron-sized HPP. In this study, micron-sized HPP exhibiting the high hiding power and narrow particle distribution could be obtained.