• Journal of Environmental Science International
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• v.30 no.3
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• pp.279-287
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• 2021

In this study, the composition and morphology of deposited dust particles with size ranging from a few to tens ㎛ were investigated using SEM/EDX (scanning electron microscopy with energy dispersive x-ray spectrometer). Then deposited dust particles were classified into 8 groups: quartz, aluminosilicates, ca-rich, Fe/Ti oxide, carbon-rich, industrial particle, Fe-rich, and biogenic particle. The sources of deposited dust were high in the order of aluminosilicates 41% > biogenic 18% > Fe-rich 11% > quartz and C-rich 8% > industrial 7% > Fe/Ti oxide 5% > Ca-rich 1%. In particular, the ratio of biogenic particles was relatively high due to influence of pollen. The ratio of carbon-rich was 11% at YM site, 10% at MD site, and 4% at MO site, and the site close to the large emission source was high.

• KEPCO Journal on Electric Power and Energy
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• v.7 no.2
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• pp.237-240
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• 2021

Failure of a suspension clamp made of hot dip galvanized cast iron in 154kV transmission tower was investigated. Metallurgical analysis of a crack of the clamp was performed using a digital microscope, an optical microscope, and a scanning electron microscope. It was revealed that the crack surface was covered by continuous zinc layer. Distinctive casting skin was found underneath both the outer surface and crack surface. The result showed that pre-existing crack had been formed in the fabrication, and liquid metal embrittlement during hot dip galvanization may assist crack propagation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.170-171
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• 2021

This study compared the characteristics of the newly established JISA 5011-5 coal gasification slag fine aggregate with the characteristics of CGS generated in Korean IGCC through microscopic analysis. As a result of the study, similar results to K_CGS and J_CGS were found

• Journal of the Korean Chemical Society
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• v.47 no.3
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• pp.250-256
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• 2003

In this work, the effect of cationic initiator content on the electron-beam (EB) curing process of diglycidylether of bisphenol-A (DGEBA) resin was studied using near-infrared spectroscopy (NIRS), thermogravimetric analysis (TGA), and critical stress intensity factor $(K_{IC})$. Benzylquinoxalinium hexafluoroantimonate (BQH) were used as an initiator and its content was varied from 0.5 to 3 phr. NIRS measurements showed that the hydroxyl group of EB-cured epoxy resin was increased with increasing the BQH content. Thermal stability and $K_{IC}$ value of EB-cured epoxy resin were increased with increasing the BQH content but were decreased above 2 phr content. These results could be attributed to the decrease of the conversion and degree of crosslinking. In another word, the conversion and degree of crosslinking were restricted by the incomplete network structure from high reactivity at the BQH content above 2 phr, resulting in decreasings of thermal stability and $K_{IC}$.

• Journal of the Korean Society of Radiology
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• v.9 no.7
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• pp.459-465
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• 2015

Energy absorption distribution according to lead shielding for 511 keV ${\gamma}$ ray was evaluated using a Monte Carlo simulation in PET/CT. Experimental method was performed about the depth of skin surface(0.07), lens(3) and the depth(10) was conducted by using ICRU Slab phantom. Difference of energy absorption distribution according to lead thickness and effect of air gap according to distance of lead and phantom. As a result, study showed that using a lead shielding makes high energy distribution by backscatter electron. As a distance between lead and phantom increased, energy absorption distribution gradually decreased. 9 cm or more air gap should exist to prevent effect of backscatter electron which reaches skin surface, when 0.25 mmPb shielding is used. Also 1 cm or more air gap was needed to prevent the effect in 0.5 mmPb. If air gap was not concerned, 0.75 mm or more lead thickness was necessary to prevent effect of backscatter electron.

• Microbiology and Biotechnology Letters
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• v.35 no.3
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• pp.210-219
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• 2007

In this study was investigated the growth effect of native plant (Microlepia marginata(panzer Christ., Prunella vulgaris. aleutica Fernald, Perillafrutescens var. japonica Hara., Gleichenia japonica Spreng) extracts on various lactic acid bacterias, electron donating ability, total cell count and hydroxyl radical scavenging activity. The total cell count of Enterococcus faecium KCCM 12118, Lactobacillus rhamnosus KCCM 32826, Lactobacillus plantarum KCCM 11542, Pediococcus pentosaceus KCCM 40464 in the absence of native plant extracts (10%) at $37^{\circ}C$ after 48hr were $2.2{\times}10^9\;cfu/ml$, $2.1{\times}10^9\;cfu/ml$, $2.3{\times}10^9\;cfu/ml$, $2.2{\times}10^9\;cfu/ml$. On the other hand, the total cell count of E. faecium KCCM 12118, L. rhamnosus KCCM 32826, L. plantarum KCCM 11542, P. pentosaceus KCCM 40464 in the presence of native plant extracts (10%) at $37^{\circ}C$ after 48hr were $4.3{\times}10^9\;cfu/ml$, $4.3{\times}10^9\;cfu/ml$, $4.8{\times}10^9\;cfu/ml$, $3.9{\times}10^9\;cfu/ml$. The electron donating ability indicated to E. faecium KCCM 12118, L. rhamnosus KCCM 32826, L. plantarum KCCM 11542, P. pentosaceus KCCM 40464 added by 10% native plant extracts, respectively. when 10% native plant extracts were added lactic acid bacterias, the electron donating ability is the highest. Hydroxyl radical scavenging activity of E. faecium KCCM 12118, L. rhamnosus KCCM 32826, L. plantarum KCCM 11542, P. pentosaceus KCCM 40464 showed higher than that of control.

• Journal of Life Science
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• v.17 no.11
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• pp.1547-1554
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• 2007

In this study was investigated the growth effect of Prunella vulgaris. aleutica Fernald(leaf and flower) extracts on various lactic acid bacterias, electron donating ability and hydroxyl radical scavenging activity. The total cell count of Enterococcus faecium KCCM 12118, Lactobacillus rhamnosus KCCM 32826, Lactobacillus plantarum KCCM 11542, Pediococcus pentosaceus KCCM 40464 in the absence at $37^{\circ}C$ after 48hr were $2.2{\times}10^9\;cfu/ml,\;2.1{\times}10^9\;cfu/ml,\;2.3{\times}10^9cfu/ml,\;2.2{\times}10^9\;cfu/ml$. On the other hand, the total cell count of E. faecium KCCM 12118, L. rhamnosus KCCM 32826, L. plantarum KCC 11542, P. pentosaceus KCCM 40464 in the presence of Prunella vulgaris. aleutica Fernald(leaf and flower) extracts(10%) at $37^{\circ}C$ after 48hr were $4.3{\times}10^9-4.5{\times}10^9\;cfu/ml,\;4.3{\times}10^9-4.5{\times}10^9\;cfu/ml,\;4.8{\times}10^9-4.9{\times}10^9\;cfu/ml,\;4.1{\times}10^9-4.1{\times}10^9\;cfu/ml$. The electron donating ability indicated to E. faecium KCCM 12118, L. rhamnosus KCCM 32826, L. plantarum KCCM 11542, P. pentosaceus KCCM 40464 added by 10% Prunella vulgaris. aleutica Fernald(leaf and flower) extracts, respectively. when 10% native plant extracts were added lactic acid bacterias, the electron donating ability is the highest. Hydroxyl radical scavenging activity of L. plantarum KCCM 11542, L. rhamnosus KCCM 32826, E. faecium KCCM 12118, P. pentosaceus KCCM 40464 showed higher than that of control.

• Applied Microscopy
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• v.30 no.2
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• pp.185-191
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• 2000

An unusually large protein complex was found in the cytosol of the hyperthmophilic archaeon. Thermococcus profundus. The purified protein was shown to be a homomultimer of 93 kDa subunit (P93 complex). The complex is extremely heat stable. During 12 hrs incubation with SDS (final concentration 1%) at $85^{\circ}C$, no changed structure could be observed. Electron image analysis of negatively stained showed that the complex has a single, stable characteristic view and a well-preserved core with threefold rotational symmetry. The periphery of the assembly is composed of a nebulose, possibly flexible, component. Based on the projected structure suggest the P93 complex from T. profundus is composed 24 homomultimer.

• Molecular & Cellular Toxicology
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• v.4 no.3
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• pp.177-182
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• 2008

Caveolin proteins are mediators of cell death or the survival of injured cells, and they are inhibitors of various signaling pathways. The expression of caveolin-, which is involved in the protein kinase A (PKA) signaling pathway, was examined in the differentiated mouse vestibular cell line UB/UE-1 after gentamicin ototoxicity. Caveolae in the vestibular hair cell of healthy guinea pigs were observed through an electron microscope. UB/UE-1 cells were cultured at 95% $CO_2$ with 5% $O_2$ at $33^{\circ}C$ for 48 hours and at 95% $CO_2$ with 5% $O_2$ at $39^{\circ}C$ for 24 hours for differentiation. Cells were treated with 1 mM gentamicin, 0.02 mM H89 (PKA inhibitor), and then incubated for 24 hours. Caveolin-1 expression was examined by western blotting and PKA activity by a $PepTag^{(R)}$ assay. Caveolae were observed in the vestibular hair cells of healthy guinea pigs by electron microscopy. Caveolin-1 was expressed spontaneously in differentiated UB/UE-1 cells and increased after gentamicin treatment. PKA was also over-activated by gentamicin treatment. Both gentamicin-induced caveolin-1 expression and PKA over-activation were inhibited by H89. These results indicate that gentamicin-induced caveolin-1 expression is mediated by the PKA signaling pathway. We conclude that caveolae/ caveolin activity, induced via a PKA signaling pathway, may be one of the mechanisms of gentamicin-induced ototoxicity.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.9
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• pp.589-593
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• 2014

AlNO multi-layer thin films on aluminum substrates were prepared by DC reactive magnetron sputtering method. $Al_2O_3$/AlNO(LMVF)/AlNO(HMVF)/Al/substrate of 4 multi-layer has been prepared in an Ar and ($N_2+O_2$) gas mixture, and $Al_2O_3$ of top layer is anti-reflection layer on double AlNO(LMVF)/AlNO(HMVF) layers and Al metal of infrared reflection layer. In this study, the roughness and surface properties of AlNO thin films were estimated by field emission scanning electron microscopy(FE-SEM). The grain size of AlNO thin films increased with increasing sputtering power. The composition of thin films has been systematically investigated using electron probe microanalysis(EPMA). The optical properties with wavelength spectrum were recorded by UV-Vis-NIR spectrophotometry at a range of 200~1,500 nm. The absorptance of AlNO films shows the increasing trend with swelling ($N_2+O_2$) gas mixture in HMVF and LMVF deposition. The excellent optical performance showed above 98% of absorptance in visible wavelength region.