• Korean Journal of Microbiology
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• v.8 no.2
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• pp.85-89
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• 1970

Effects of the sugar content in molasses media and pH on cell constituents of produced yeast adopting Saccharomyces cerevisiae Rasse O as a seed organism were studied, and following results were obtained. 1. Trehalose accumulation of the yeast was reduced at lower range of pH, however protein was increased. 2. Trehalose content of the yeast enriched by feeding increased sugar at suitable pH. 3. There was no significant increase of thehalose content in the cell by feeding concentrated molasses at lower range of pH.

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.114-115
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• 2007

In this study, low temperature sintering property of the $0.6TiTe_3O_8-0.4MgTiO_3$ ceramics with sintering adds were investigated for LTCC application which enable to cofiring with Ag electrode. $TiTe_3O_8$ mixed with $MgTiO_3$ to improve the temperature property. In the X-ray diffraction patterns, the columbite structure of $TiTe_3O_3$ phase and ilmenite structure of $MgTiO_3$ phase were coexisted in all specimens. In the case of $H_3BO_3$ addition, the bulk density and dielectric constant were decreased but quality factor was increased with amount of $H_3BO_3$ additions. The TCRF of the $0.6TiTe_3O_8-0.4MgTiO_3+xwt%H_3BO_3$ ceramics were moved to positive direction. In another case, SnO addition, the bulk density and dielectric constant were increased but Quality factor was decreased with amount of SnO additions. The TCRF of the $0.6TiTe_3O_8-0.4MgTiO_3$+ywt%SnO ceramics were shifted to negative direction. The dielectric constant, quality factor and TCRF of the $0.6TiTe_3O_8-0.4MgTiO_3$ ceramics with $2wt%H_3BO_3$ and 2.5wt%SnO sintered at $830^{\circ}C$ for 1h, were 28.5, 39,570GHz, $+9.34ppm/^{\circ}C$ and 29.86, 35,80000z, $-0.58ppm/^{\circ}C$, respectively.

• Korean Journal of Materials Research
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• v.8 no.12
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• pp.1110-1114
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• 1998

The crystallization behaviors and electrical conductivities of the glasses heat-treated at various times and temperatures in the CuO-Bi$_2$O$_3$-V$_2$O$_{5}$ glass system were investigated. Among glass samples with various compositions, the highest conductivity obtained in the 31CuO-14Bi$_2$O$_3$-55V$_2$O$_{5}$ (mol%) glass sample. The 31CuO-14Bi$_2$O$_3$-55V$_2$O$_{5}$ (mol%) glass sample crystallized by heat treatment at 358$^{\circ}C$ for 8h had 2.67$\times$10$^{-2}$ $\Omega$$^{-1}$ $cm^{-1}$ /, which was much high value as a solid electrolyte. Compared to the glass sample, the heat- treated glass sample was increased in conductivity by an order of 10$^3$-10$^4$due to the formation and growth of BiVO$_4$ and CuVO$_3$crystals.

• Journal of Environmental Science International
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• v.21 no.4
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• pp.421-435
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• 2012

Novel $N_2O_2$ tetradentate ligands, H-3BPD and H-2BPD were synthesized. Hydrochloric acid salts of Br-3BPD, Cl-3BPD, Br-2BPD and Cl-2BPD having Br and Cl substituents at the $para$ position of the phenol hydroxyl group, were synthesized. The ligands were characterized by C. H. N atomic analysis, $^1H$ NMR, $^{13}C$ NMR, UV-visible, and mass spectra. The proton dissociation constants ($logK_n{^H}$) of the phenol hydroxyl group and secondary amine of the synthesized $N_2O_2$ ligands were shown by four step wise values. The orders of the calculated overall proton dissociation constants ($log{\beta}_p$) were Br-3BPD < Cl-3BPD < H-3BPD in case of 3BPD and Br-2BPD < Cl-2BPD < H-2BPD in case of 2BPD respectively. The order agreed well with that of $para$ Hammett substituent constants(${\delta}_p$). The stability constants($logK_{ML}$) of the complexes between the synthesized ligands and transition metal(II) ions agreed with the order of $log{\beta}_p$ of the ligands. The order of the $logK_{ML}$ value of the each transition metal (II) ion was Co(II) < Ni(II) < Cu(II) > Zn(II) > Cd(II) > Pb(II), which agreed well with that of Iriving-Williams series.

• The Journal of Internal Korean Medicine
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• v.41 no.1
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• pp.44-58
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• 2020

Objectives: This study was conducted to identify the protective effects of Chongmyunggongjin-dan (CMGJD) on Hydrogen peroxide (H₂O₂)-induced apoptosis mechanisms in C6 glial cells. Method: We used CMGJD after distilled water extraction, filtration, and lyophilization. The ROS scavenging effect was examined by fluorescence microscopy. Expression levels of proteins related to ROS generation were investigated by western blotting. Functional changes in organelles related to Reactive oxygen species (ROS) generation were investigated by immunoblotting and by verifying expression level of relevant enzymes. Results: The CMGJD extract protected the cells against H₂O₂-induced morphological changes and DNA fragmentation, inhibited the increase of Heme_oxygenase-1(HO^-1) and the decrease in catalase, protected against the loss of mitochondrial membrane potential, inhibited disturbances of lysosomal function, and induced an increase in peroxisomes. Conclusion: CMGJD was confirmed to have a protective effect on H₂O₂-induced C6 glial cell death possibly by blocking the pathways causing damage to subcellular organelles, such as mitochondria, lysosomes, and peroxisomes. We assume that CMGJD will be effective for the prevention and treatment of ischemic stroke in a clinical environment.

• Journal of Korean Society on Water Environment
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• v.36 no.4
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• pp.314-321
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• 2020

This study evaluated the applicability of UV-AOP process using medium-pressure UV lamp and H₂O₂ to remove TOC and emerging micropollutants in the effluent from a sewage treatment plant. The UV lamp with higher output(1.6~8.0 kW) showed slightly higher amount of power in removing TOC of 1 mg/L(0.09 kWh/mg/L~0.11 kWh/mg/L), however it was found that there was no significant difference for each cases. In addition, under the condition that the H₂O₂ concentration is sufficient, as the power consumption of the UV lamp increases, the unit TOC removal concentration per unit H₂O₂ decomposition concentration also increases, resulting in effective removal of TOC. The removal rate of 7 new trace contaminants, such as antibiotics by the UV-AOP tested, was at least 89.4%, and the ability to remove the emerging micro pollutants in the process was very effective. But, it was judged that it could not be excluded that the probablity of transforming to oxidated by-product in the case of a low TOC removal efficiency. Depending on the operating conditions of the UV and H₂O₂ processes, a higher BOD concentration is found in the treated water than in the influent, and it is necessary to review the UV power and proper injection conditions of H₂O₂ to maintain the BOD concentration increase below a certain level.

• Journal of Ginseng Research
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• v.30 no.1
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• pp.1-7
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• 2006

Ceramide has been involved in celt death and acted as a lipid mediator of stress responses. Elevation of ceramide level was reported to occur in oxidative stress and lead to cell death in many cell types. This study was undertaken to elucidate a protective role of ginsenoside Rgl in cell death induced by oxidative stress. When LLC-PK1 cells were treated with $H_2O_2$ at a concentration of $400{\mu}M$ for 5 hr, cell death was observed and a released LDH activity indicative of cytotoxicity was Increased. $H_2O_2$ exposure to LLC-PK1 cells was shown to elevate the content of total ceramide by approximately 200% compared to control cells. Ceramide level was hypothesized to be a key to a reversal of cell death to survival. Ginsenoside Rgl at the concentrations ranging from 12.5 to $250{\mu}M$ protected LLC-PK1 cells from cell death induced by $H_2O_2\;at\;400{\mu}M$ for 5 hr, and decreased the ceramide level relative to $H_2O_2$. Ginsenoside Rgl inhibited neutral human ceramidase by 71% of controls, while sphingomyelinase was not inhibited. These results suggest that ginsenoside Rgl show the protection against cell death via the modulation of ceramide metabolism, and ceramide may be a promising therapeutic target for human diseases related to cell death.

• Resources Recycling
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• v.21 no.6
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• pp.74-81
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• 2012

The Influence of temperature on the recovery reaction of silver in aqueous solution was investigated based on Pourbaix diagram constructed by thermodynamic calculation at different temperatures. It was observed that the stability of water is more strongly affected by pH variation and the stable region of ${Ag^+}_{(aq)}$ is diminished at higher temperature. It was shown that the recovery of $Ag_{(aq)}$ in the forms of $Ag_{(s)}$ and $Ag_2O_{3(s)}$ is more advantageous thermodynamically at lower temperature, however, the recovery of $Ag_{(aq)}$ in the forms of $Ag_2O_{(s)}$ 및 $Ag_2O_{2(s)}$ is more advantageous as temperature increases. The rise of temperature is considered to demote the recovery of silver thermodynamically in strong acidic condition ($pH{\leq}2$), but more silver is regarded to be recovered with temperature above pH 2. Finally, The recovery of silver in the elemental state is shown to be more sensitively influenced by temperature variation compared with the recovery of silver in its oxide form.

• The Korea Journal of Herbology
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• v.28 no.4
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• pp.57-62
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• 2013

Objectives : Lonicerae Japonicae Flos (LJF) has been shown anti-oxidant, anti-inflammatory, anti-viral, anti-rheumatoid properties. However, it is still largely unknown whether LJF inhibits skin injury against oxidative stress in human keratinocyte, HaCaT cells. The purpose of this study was to evaluate the protective effects of LJF against hydrogen peroxide($H_2O_2$)-induced oxidative stress in human keratinocytes, HaCaT cells. Methods : To evaluate out the protective effects of LJF on oxidative injury in HaCaT cells, an oxidative stress model of HaCaT cells was established under a suitable concentration (500 ${\mu}M$) hydrogen peroxide. HaCaT keratinocyte cells were pre-treated with LJF (0.1, 0.25 or 0.5 mg/ml), and then stimulated with $H_2O_2$. Then, the cells were harvested to measure the cell viability, DNA damage, and release of reactive oxygen species (ROS). Results : LJF (0.1, 0.25 or 0.5 mg/ml) itself did not show any significant toxicity in HaCaT cells. The treatment of $H_2O_2$ caused the oxidative stress, leading to the cell death, and DNA injury. However, pretreatment with LJF reduced cell death, and DNA injury. The stimulation of $H_2O_2$ on HaCaT cells resulted in excessive release of ROS, which is the main factor of oxidative stress. The excessive release of ROS was inhibited by LJF treatment significantly. Conclusions : These results could suggest that LJF exhibited the protective effects of HaCaT cells against $H_2O_2$-induced oxidative stress by inhibiting ROS release. It could be explained that LJF inhibit skin damages against oxidative stress. Thus, LJF would be useful for the development of drug or cosmetics treating skin troubles.

• Progress in Superconductivity
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• v.11 no.2
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• pp.123-127
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• 2010

The properties of buffer layer for thermal and chemical stability in coated conductor is a very important issue. $CeO_2$ has desirable thermal and chemical stability as well as good lattice match. In this study, $CeO_2$ was deposited by electron beam deposition. The MgO(001) single crystal and LMO buffered IBAD substrate(LMO/IBAD-MgO/$Y_2O_3/Al_2O_3$/Hastelloy) were used as substrates, which have $\Delta\phi$ values of ${\sim}8.9^{\circ}$. The epitaxial $CeO_2$ films was deposited with high deposition rate of $12{\sim}16\;{\AA}/sec$. During deposition, the change of oxygen partial pressure(${\rho}O_2$) does not cause change in c-axis texture. In case of $CeO_2$ on MgO single crystal, the substrate temperature was optimized at $750^{\circ}C$ with superior $\Delta\phi$ and $\Delta\omega$ value. Otherwise, In case of LMO buffered IBAD substrate, It was optimized at $650^{\circ}C$ with increasing its deposition thickness of $CeO_2$, which was finally obtained with best $\Delta\phi$ value of $5.5^{\circ}$, $\Delta\omega$ value of $2^{\circ}$ and Ra value of 2.2 nm.