• Biomedical Science Letters
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• v.10 no.3
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• pp.263-268
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• 2004

This study was carried out to evaluate the cytotoxic effect of phenolic compound on normal NIH 3T3 fibrolasts. The colorimetric assay for phenol compound, syringic acid was performed by MTT assay or XTT assay. MTT or XTT assays are known as a very sensitive method in measuring the cytotoxic effect of chemical agents in vitro. In the present study, syringic acid on normal Nlli 3T3 fibroblasts did not show any cytotoxicity for MTT assay or XTT assay compared with control after cells were treated with various concentrations of syringic acid for 48 hours. MTT/sub 50/ and XTT/sub 50/ were 3,340.9 μM and 2,462.4 μM of syringic acid, respectively. From the above the results, it is suggested that phenolic compound of syringic acid did not have any cytotoxicity on normal NIH 3T3 fibroblasts.

• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.296-301
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• 2009

The ice storage system uses water for low temperature latent heat storage. However, a refrigerator capacity is increased and COP is decreased due to supercooling of water in the course of phase change from solid to liquid. This study investigates the cooling characteristics of the TMA-water clathrate compound including TMA (Tri-methyl-amine, $(CH_3)_3N)$ of $20{\sim}25wt%$ as a low temperature latent heat storage material. The results showed that the phase change temperature and the specific heat is increased and the supercooling degree is decreased as the weight concentration of TMA increased. Especially, the clathrate compound containing TMA 25wt% has the average phase change temperature of $5.8^{\circ}C$, the supercooling degree of $8.0^{\circ}C$ and the specific heat of 3.499 kJ/kgK in the cooling process. This can lead to reduction of operation time of refrigerator in low temperature latent heat storage system and efficiency improvement of refrigerator COP and overall system. Therefore, energy saving and improvement of utilization efficiency are expected.

• Applied Chemistry for Engineering
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• v.5 no.6
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• pp.943-948
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• 1994

The properties of uncured rubber compound and swelling behavior of cured rubber compound with carbon black(N33O grade) increment. Bound Rubber content(BRC) increased according to carbon black increment and ${\alpha}_f$, behavior of uncured rubber compound filled with carbon black, was 1.46. Carbon black added to rubber compound showed behavior of spherical particle by bound rubber. The $C_1$ values of cured rubber compounds, which measured by the stress-strain method of Mooney-Rivlin, increased with carbon black increment.

• 한국초전도학회:학술대회논문집
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• v.10
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• pp.1-1
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• 2000

The infinite layer compound $ACuO_2$, (A-Alkaline earth) consists of infinite stacking of $CuO_2$ planes separated only by alkaline earth ions. This compound attracted much attention because it contains only key ingredient of all cuprate high temperature superconductor; $CuO_2$ plane with controllable carrier concentration without charge reservoir block. High pressure synthesis method has been found to be preferable for this system due to its ability of doping various lanthanide ion into A site with larger superconducting volume fraction. But rigorous study on this rudimentary compound has been hindered by insufficient quality of sample. Especially superconductlng volume fraction was often too small to identify its origin. In this presentation, we report high pressure synthesis of $Sr_{0.9}Ln_{0.1}CuO_2$ (Ln=La, Sm). By controlling the heating temperature precisely during high pressure synthesis we could have superconductors with quite high superconducting volume fraction for this compound. The magnetic properties of the graln aligned samples show very different behavior compared to the cuprate high temperature superconductors. Details will be discussed.

• Journal of the Korean Society of Safety
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• v.30 no.6
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• pp.12-17
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• 2015

In this study, the collapse characteristic of CFRP/Al compound square tube was investigated experimentally. The conclusions are as follows; The impact collapse characteristic of CFRP/Al compound square tube was found to be the most superior stacking conditions $[90^{\circ}]_8$. It showed that a very stable collapse mode was crushing. In the member with $[0_2{^{\circ}}/90_2{^{\circ}}]_s$ and $[90_2{^{\circ}}/0_2{^{\circ}}]_s$, stacking conditions, $0^{\circ}$ fibers were splayed to the external by laminar bending, while the $90^{\circ}$ fibers were held between the folds of the aluminum member by laminar bending, local buckling and transverse crack. In the member with $[45_2{^{\circ}}/45_2{^{\circ}}]_s$ stacking conditions, fibers were held between the folds of the aluminum member by local buckling and transverse crack.

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.709-715
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• 1999

A series of antifungal compounds were obtained from the methanol extract of the mycelium from marine actinomycetes M428 which was identified as a Stereptomyces species by fatty acid composition and biochemical characteristics. These compounds were purified by combined chromatographic techniques and the structures were characterized with spectroscopic methods including 1D and 2D NMR, and mass spectrometry as sn-l lysophosphatidyl inositols. The side chains were established by chemical degradation followed by GC analysis to be 14-methyl pentadecanoic acid (iso-palmitic acid, i-C16:0, compound A) and 13-methyl tetradecanoic acid (iso-pentadecanoic acid, i-C15:0, compound B). These compounds displayed highly selective antifungal activity against C. albicans with MIC values of $5{\;}\mu\textrm{g}/ml$ (compound A) and $2.5{\;}\mu\textrm{g}/ml$ (compound B), while it had almost negligible antibiotic activity against E. coli and P aerogenosa with MIC value higher than $50{\;}\mu\textrm{g}/ml$ and no cytotoxic activities against human myeloma leukemia K562 ($IC_{50}>100{\;}\mu\textrm{g}/ml$).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.258-259
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• 2005

[ $CuInSe_2$ ] thin films were fabricated at various fabrication conditions (substrate temperature, sputtering pressure, BC/RF power, vapor deposition, heat treatment). And structural and electrical properties were measured in order to certify optimum conditions for growth of the ternary compound semiconductor $CuInSe_2$ thin films with stoichiometric composition. $CuInSe_2$ thin film was well made at the heat treatment of 500[$^{\circ}C$] of SLG/Cu/In/Se stacked elemental layer which was prepared by sputter and thermal evaporator, and chemical composition of the thin film was analyzed nearly as the proportion of 1 : 1 : 2. At the same time, carrier concentration, hall mobility and resistivity of the thin films was $1.27\sim9.88\times10^{17}[cm^{-3}]$, $49.95\sim185[cm^2/V{\cdot}s]$ and $10^{-1}\sim10^{-2}[\Omega{\cdot}cm]$, respectively

• Journal of the Korean Society for Heat Treatment
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• v.2 no.4
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• pp.27-39
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• 1989

The effect of gas mixing ratios during gas nitrocarburizing treatment on the formation of compound layer and the mechanical properties has been studied for hot work tool steel by using a combined heat treating technique. The thickness of compound and diffusion layers has been shown to grow as a parabolic relation with increasing the amount of ammonia at a given flow quantity of $CO_2$ gas. The compound layer consists mainly of ${\varepsilon}-Fe_3$(C, N) with small amounts of ${\gamma}^{\prime}-Fe_4N$ and ${\alpha}$-Fe. The combined heat treated hot work tool steel has shown that the thickness of compound layer increases with increasing nitrocarburizing time, but the rate of growth slows down as gas nitrocarburizing time goes more than two hours. Tensile properties have given a remarkable improvement. In particular, the wear resistance of combined heat treated hot work tool steel has exhibited an improvement of about 165% greater than that obtained from conventional quenching and multi-tempering treatments.

• Korean Journal of Pharmacognosy
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• v.28 no.2
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• pp.88-92
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• 1997

The full NMR assignment of hispidulin 7-0-neohesperidoside (1) isolated from Cirsium japonicum var. ussuriense was made with the aid of 2D correlation NMR techniques such as HMQC and HMBC. To investigate detoxification of bromobenzene-induced hepatic lipid peroxidation by compound 1, hepatic lipid peroxide level and the activities of enzymes responsible for production and removal of epoxide were studied. The level of lipid peroxide elevated by bromobenzene was significantly reduced by compound 1. This compound administered daily over one week before intoxication with bromobenzene did not affect the activities of aminopyrine N-demethylase, aniline hydroxylase, glutathione S-transferase. Epoxide hydrolase activity was decreased significantly by bromobenzene, which was restored to the control level by pretreatment of persicarin. The results suggest that the bromobenzene-induced hepatic lipid peroxidation by compound 1 is reduced by enhancing the activity of epoxide hydrolase, an enzyme removing bromobenzene epoxide.

• International Journal of Air-Conditioning and Refrigeration
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• v.17 no.1
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• pp.32-36
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• 2009

The ice storage system uses water for low temperature latent heat storage. However, a refrigerator capacity is increased and COP is decreased due to supercooling of water in the course of phase change from solid to liquid. This study investigates the cooling characteristics of the TMA-water clathrate compound including TMA (Tri-methyl-amine, $(CH_3)_3N$) of $20{\sim}25wt%$ as a low temperature latent heat storage material. The results showed that the phase change temperature and the specific heat is increased and the supercooling degree is decreased as the weight concentration of TMA increased. Especially, the clathrate compound containing TMA 25 wt% has the average phase change tempera ture of $5.8^{\circ}C$, the supercooling degree of $8.0^{\circ}C$ and the specific heat of 3.499 kJ/kgK in the cooling process. This can lead to reduction of operation time of refrigerator in low temperature latent heat storage system and efficiency improvement of refrigerator COP and overall system. Therefore, energy saving and improvement of utilization efficiency are expected.