• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.10a
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• pp.95-96
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• 2003

We investigated the proteins that are associated with initiation, maintenance, and termination of diapause in silkworm eggs by means of 2D-gel electrophoresis. 1. Materials : Bombyx mori: unfertilized eggs, diapause eggs, non-diapause eggs, cold-treated egges. 2. Methods: isoelectric focusing, SDS-PAGE, silver staining. (omitted)

• Journal of the Korean Ceramic Society
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• v.26 no.5
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• pp.631-636
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• 1989

Submicron high-purity mullite powder was prepared by a colloidal sol-gel route. Boehmite and silica were the starting materials. 2wt% $\alpha$-Al2O3 or ZrO2 was used as a seeding material. The gelled powder was calcined at 130$0^{\circ}C$ for 100min and attrition milled for 3hrs. The mullite powder obtained was composed of submicrometer and uniform particles with a narrow size distribution. It was hot-pressed at 1$600^{\circ}C$ for 1hr under 10MPa or was sintered at 1$650^{\circ}C$ for 4hrs. The bulk densities of the products made by both processes were 3.14 and 3.12g/㎤. the mechanical, thermal and electrical properties of the sintered mullite were characterized by bending strength, thermal expansion coefficient, thermal conductivity, dielectric constant and dielectric loss, etc.

• Journal of the Korean Ceramic Society
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• v.26 no.5
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• pp.682-690
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• 1989

Fine mullite powder was prepared by colloidal sol-gel route. Boehmite as a starting material of Al2O3 and silica sol or fumed silica as a starting material of SiO2 were used. $\alpha$-Al2O3, TiO2 and ZrO2 were used as seeding materials. The combination of boehmite and silica was found to be the stoichiometric mullite powder. Techniques for drying used were spray drying, freeze drying, reduced pressure evaporation and drying in a oven. The gelled powder was heated at 130$0^{\circ}C$ for 100min and was attrition-milled for 1~3hrs. The mullite powder obtained was composed of submicrometer, uniform and spherical particles with a narrow size distribution. The mullite powder was characterized by BET, SEM, XRD and IR spectroscopy.

• International Journal of Concrete Structures and Materials
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• v.8 no.1
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• pp.61-68
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• 2014

This paper reports the physical properties and hydration products of slag cement that was prepared by activating ground granulated blast furnace slag with commercial lime and plaster of Paris (POP) as activators. The consistency, setting times and soundness of various mixes of slag-lime-POP is reported. The hydration products and formation of bonds in the paste during setting were studied with the help of SEM, FTIR and XRD tests and the same are correlated to the hydration process. The setting times of the mixes are found to be lower than that of the value prescribed for ordinary Portland cement (OPC). Borax is used as a setting retarder and a borax content of 0.4 % by mass gives setting times that are normally prescribed for OPC. In the early stages of setting C-A-S-H gels are found in this cementing material instead of C-S-H gel, as generally observed in the OPC.

• BMB Reports
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• v.31 no.4
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• pp.405-408
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• 1998

Endonuclease-sensitive sites detected by T4 endonuclease V or UvrABC nuclease treatments were compared in the dihydrofolate reductase gene of UV-irradiated Chinese hamster ovary B-11 cells. The number of endonuclease-sensitive sites detected by T4 endonuclease V treatment followed by NaOH denaturation was twice that of formamide denaturation. Repeated treatment of damaged genomic DNA with T4 endonuclease V resulted in no further increase in the number of endonuclease-sensitive sites detected. The numbers of endonuclease-sensitive sites detected by UvrABC nuclease using each denaturation condition were similar. Sequential treatment with the two endonucleases using formamide denaturation resulted in twice the number of endonuclease-sensitive sites detected by treatment of each nuclease alone. Due to a lack of AP endonuclease activity these results suggest the presence of T4 endonuclease V-sensitive sites which could be complemented by alkaline gel separation or by UvrABC nuclease treatment.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.3
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• pp.387-393
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• 2008

This paper has dealt with the probability of oyster shell desiccant cooling system driven by renewable energy of photo-volatic effect with fundamental experiment. The test materials for desiccant are activated charcoal, silica-gel, hi-dry, and oyster shell. The experiments were mainly performed with focusing on the observation of surface features, adsorption amounts of the adsorbent species, and the effect of temperature. Oyster shell has sufficient probability for using as desiccant in a air-conditioning system. Moreover, the heat releasing device would be attached in the system, the system based with oyster shell can be operated with high efficiency.

• Korean Journal of Pharmacognosy
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• v.45 no.1
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• pp.35-40
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• 2014

In this study, in order to search for new functional materials from natural products, was carried out the study of antioxidant active ingredients in persimmon calyx(calyx of Diospyros kaki Thunberg). I have experimented with the effect of antioxidant activity of five different extract(MeOH, n-hexane, EtOAc, n-BuOH and $H_2O$ extract) obtained from persimmon calyx. As a result, the butanol extract, that is the main component fraction of antioxidant activity was found. Three compounds were isolated by silica gel column chromatography from the n-BuOH extract of persimmon calyx. Their structures of compound 1, 2 and 3 isolated from n-BuOH extract of persimmon calyx were identified as quercetin, (+)-catechin and gallic acid by using the TLC, $^1H$-NMR and $^{13}C$-NMR.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.342-345
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• 2001

A bacterial strain PH-4, which produces an enzyme catalyzing the degradation of crosslinked poly(${\gamma}$-glutamic acid) hydrogels, was isolated and identified as a Flavobacterium sp. The enzyme was obtained by the sonication of the bacterial cells preincubated in a Bouillon medium with shaking, without adding of poly(${\gamma}$-glutamic acid) as an inducer. The products of the hydrogel degraded by the crude enzyme agreed closely with the depolymerized materials in SDS-polyacrylamide gel electrophoresis using methylene blue staining, and with a glutamic acid monomer on thin-layer chromatography, thereby suggesting that strain PH-4 produced a kind of exohydrolase.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.4
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• pp.865-871
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• 2009

Chondroitin sulfate was extracted by alkali method and enzyme method from shark cartilage. In extract system, various processing parameters such as concentration of alkali and alcarase, temperature etc, have been investigated for optimization condition. The pure chondroitin sulfate was obtained by UF membrane separation. The characteristics was also investigated with gel permeation chromatograpy(GPC). The molecular weight of chondroitin sulfate was $2.7\times10^4$ Da.

• 한국연소학회:학술대회논문집
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• 2007.05a
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• pp.37-44
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• 2007

A nickel foam, one of metal foams was seleced as a catalyst support instead of conventional ceramic materials. $Al_2O_3$ was coated on the surface of nickel foam to increase the surface area. $Al_2O_3$ coating process was based on sol-gel process. SEM image was obtained and $Al_2O_3$ coverage was confirmed. Combustion experiments were carried out using SUS combustor and $H_2$/air mixture. Temperatures were measured with different equivalence ratios and $H_2$ flow rates. $H_2$ conversion rates were calculated by the analysis of product gas using gas chromatography. Catalytic combustion of $H_2$ was complete and stable with Pt/$Al_2O_3$ coated nickel foam and influences of water vapor were confirmed during the beginning of combustion.