• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.206.2-206
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• 2003

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.6
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• pp.725-730
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• 1992

The internal invertase was purified from cell free extract of Rhodosporidium toruloides IFO 0559-M-919 by acid precipitation, ion-exchange chromatography and gel filtration to the unique enzyme protein on disc electrophoresis. We have found out that molecular weight of purified internal invertase was 90,000 by gel filtration and the purified enzyme was protein with 4 homogeneous subunits appearing as single band of 22,000daltons on SDS-polyacrylamide gel electrophoresis.

• Restorative Dentistry and Endodontics
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• v.29 no.4
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• pp.370-377
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• 2004

The purpose of this study was to regenerate human dental pulp tissues similar to native pulp tissues. Using the mixture of type I collagen solution, primary cells collected from the different tissues (pulp, gingiva, and skin) and NIH 3T3 ($1{\;}{\times}{\;}10^5{\;}cells/ml/well$) were cultured at 12-well plate at $37^{\circ}C$ for 14 days. Standardized photographs were taken with digital camera during 14 days and the diameter of the contracted collagen gel matrix was measured and statistically analyzed with student t-test. As one of the pulp tissue engineering, normal human dental pulp tissue and collagen gel matrix cultured with dental pulp cells for 14 days were fixed and stained with Hematoxyline & Eosin. According to this study, the results were as follows: 1. The contraction of collagen gel matrix cultured with pulp cells for 14 days was significantly higher than other fibroblasts (gingiva, skin) (p < 0.05), 2. The diameter of collagen gel matrix cultured with pulp cells was reduced to 70.4% after 7 days, and 57.1% after 14 days. 3. The collagen gel without any cells did not contract, whereas the collagen gel cultured with gingiva and skin showed mild contraction after 14 days (88.1% and 87.6% respectively). 4. The contraction of the collagen gel cultured with NIH 3T3 cells after 14 days was higher than those cultured with gingival and skin fibroblasts, but it was not statistically significant (72.1%, p > 0.05). 5. The collagen gel matrix cultured with pulp cells for 14 days showed similar shape with native pulp tissue without blood vessels. This approach may provide a means of engineering a variety of other oral tissue as well and these cell behaviors may provide information needed to establish pulp tissue engineering protocols.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.10
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• pp.768-772
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• 1998

The new type polymer electrolyte composed of polymethyl methacrylate(PMMA) - polyethy leneoxide(PEO) contain $LiClO_4$ -EC/PC was developed for the weightless and long or life time of lithium polymer batery system with using polyaniline electrode. the gel type electrolytes were prepared by PMMA with PEO at different lithium salts in the glove box. The minimum thickness of PMMA-PEO gel electrolyte for the slim type is about(400~450$\mu\textrm{m}$. These gel electrolyte showed good compatibility with lithium electrode. The test cell Li/polymer electrolyte/polyaniline solid state cell which was prepared by different lithium salt was researched by electrochemical technique.

• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.1
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• pp.289-296
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• 2003

The evaluation on performance of gel type penetrative water-repellent for durability progress of concrete structure has carried out in this study. And liquid type waterproof agents have been estimated with same method. Also normal concrete that was not applied water-repellent and waterproof agents have been estimated. As results, the penetrative depth of gel type water-repellent were deeper than that of liquid type waterproof agents and those were superior to these in physical and durable performance.

• Journal of the Korean Society of Safety
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• v.21 no.1 s.73
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• pp.86-91
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• 2006

Oil spills caused by the accidents have been occurred from house and factory waste, grounded tanker, the rupture of storage tank and oil pipelines, the deterioration of various industrial facilities, etc. Many oil spills result in contamination of shorelines and workplace. Fire and explosion may happen from these spills. There are several technologies used for clean-up application, which include use of oil dispersing agents, absorbents, solidifiers, booms and skimmers by physical, chemical, and biological methods. Methods for oil spill clean-up operation are classified into the absorption type, gel type and self-swelling type. Porous materials with oil absorptive properties are classified into micropore, mesopore, and macropore depending on their pore sizes. Recently, new porous materials with smaller size have been developed, but the selective oil absorption in water-in-oil interface demonstrates the macro pore size. In this study oil absorption effects were evaluated using the organic porous materials with a complex function of gel type and swelling type. Samples were subjected to analysis by FT-IR spectroscopy and were characterized in terms of gel formation and morphologies. Oil sorption capacity, pressure retention force and gel strength were also measured. From these results, the physicochemical reactivity before and after gelation was verified and the industrial applications of clean-up operation were suggested.

• Elastomers and Composites
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• v.54 no.3
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• pp.247-251
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• 2019

Two different urethane acrylates (mono-acrylate and di-acrylate) were used to prepare unsaturated polyester-based hybrid gel-coats. The physical properties and surface characteristics of these gel-coats were investigated on the basis of the content and type of urethane acrylate. The set-to-touch time increased and the physical properties (surface hardness and tensile strength) decreased with an increase in the urethane acrylate content. However, the type of urethane acrylate did not affect these parameters. It was found that the optimal urethane acrylate content for the application of unsaturated polyester-based hybrid gel-coats is ~10 wt%.

• Korean journal of food and cookery science
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• v.32 no.4
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• pp.524-530
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• 2016

Purpose: The properties of starch and starch gel prepared from a newly inbred sweet potato, Daeyumi were compared to the properties of starch and starch gel prepared from Sinyulmi which is a well known mealy type sweet potato. Methods: The starch was isolated by using the alkaline steeping method. Physicochemical, pasting, and thermal properties, and crystallinity were measured. The texture properties of starch gel (10%, w/w) were examined. Results: The amylose contents of Daeyumi and Sinyulmi starches were 25.57% and 22.59%, respectively. The initial pasting temperature of Daeyumi starch was significantly higher than that of Sinyulmi starch (p<0.05), but other paste viscosities were not different. The peak and conclusion temperatures of Daeyumi starch were higher than those of Sinyulmi starch by differential scanning calorimetry. The shape of Daeyumi starch gel was more clear and rigid than the shape of Sinyulmi starch gel. The surface and the upper side of Daeyumi starch gel were smoother than the surface and the upper side of Sinyulmi starch gel. Hardness and gumminess were higher in Daeyumi starch gel than in Sinyulmi starch gel. The crystallinity types of Daeyumi and Sinyulmi starches were $C_b$ and A types, respectively, but starch gels showed an amorphous type. Conclusion: Therefore, it is suggested that Daeyumi starch would have better physicochemical properties and higher quality of starch gel than Sinyulmi starch.

• Polymer(Korea)
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• v.36 no.6
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• pp.789-794
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• 2012

Poly(lactic-co-glycolic acid) (PLGA) has been most widely used due to its advantages such as good biodegradability, controllable rate of degradation and metabolizable degradation products. We manufactured composite scaffolds of PLGA scaffold penetrated DBP gel (PLGA/DBP gel) by a simple method, solvent casting/salt leaching prep of PLGA scaffolds and subsequent soaking in DBP gel. Chondrocytes were seeded on the PLGA/DBP gel. The mechanical strength of scaffold, histology (H&E, Safranin-O, Alcian-blue) and immunohistochemistry (collagen type I, collagen type II) were performed to elucidate in vitro and in vivo cartilage-specific extracellular matrices. It was better to keep the characteristic of chondrocytes in the PLGA/DBP gel scaffolds than that PLGA scaffolds. This study suggests that PLGA/DBP gel scaffold may serve as a potential cell delivery vehicle and a structural basis for in vivo tissue engineered cartilage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.2
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• pp.129-133
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• 1997

A total 943 accession of soybeans (G. max) and 50 wild soybeans (G. soja) were examined for leucine aminopeptidase (LAP) isozyme variation by 5％ polyacrylamide gel electrophoresis(PAGE) and isoelectric focusing(IEF) of pH 4~6.5. The Lap1*b by PAGE was the most common phenotype in both G. max and G. soja. The frequency of Lap1*b allele was observed to be higher in G. max(1.00) than in G. soja(0.96) of Korea. This result shows that G. max is fixed for Lapl*b allele at the Lap1 locus. LAP isozyme band type I and II were found using IEF of pH 4~6.5 in G. max and G. soja of Korea. Type I was observed from 92.8％ in G. max and 92.0％ in G. soja, and type II was discovered in 7.2％ G. max and 8.0％ G. soja. This result suggested the possibility to be found more various band types.