• Nuclear Engineering and Technology
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• v.48 no.5
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• pp.1154-1161
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• 2016

The heat transfer characteristics between liquid lead bismuth eutectic (LBE) and helium are of great significance for the two-loop cooling system based on an accelerator-driven system (ADS). This paper presents an experimental study on the resistance characteristics and heat transfer performance in a LBE-helium experimental loop of ADS. Pressure drops in the LBE loop, the main heat transfer, and the coupled heat transfer characteristics between LBE and helium are investigated experimentally. The temperature of LBE has a significant effect on the LBE thermo-physical properties, and is therefore considered in the prediction of pressure drops. The results show that the overall heat transfer coefficient increases with the increasing helium flow rate and the decreasing inlet temperature of helium. Increasing the LBE Reynolds number and LBE inlet temperature promotes the heat transfer performance of main heat transfer and thus the overall heat transfer coefficient. The experimental results give an insight into the flow and heat transfer properties in a LBE-helium heat exchanger and are helpful for the optimization of an ADS system design.

• Korean Journal of Food Science and Technology
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• v.54 no.2
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• pp.147-154
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• 2022

The Mongolian lingonberry and blueberry are two essential food sources found in Mongolia. This study investigated the antioxidant and anti-inflammatory effects of methanol extracts from Mongolian lingonberry (LBE) and blueberry (BBE). Compared to the LBE, the BBE showed higher total phenolic, flavonoid, and anthocyanin contents, as well as antioxidant capacities. The LBE and BBE inhibited the mRNA expression of pro-inflammatory genes, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and cyclooxygenase (COX-2) in lipopolysaccharide-stimulated RAW 264.7 macrophage cells. In addition, the LBE and BBE inhibited NADPH oxidase-2 (Nox2) mRNA expression, indicating that they have cellular antioxidant capacities. Anthocyanin derivatives of the LBE and BBE were analyzed using LC-QTOF/MS. Six anthocyanins were identified in the BBE, while one was detected in the LBE. Our findings demonstrate that the anthocyanin-rich LBE and BBE could be used as functional food sources in Mongolia.

• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3919-3927
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• 2022

This study presents an optimal design of the coolant system of a non-refueling full-life small reactor by analyzing the space-integrated geometrical and electromagnetic variables of an extra vessel electromagnetic pump (EVEMP) for the circulation of a lead-bismuth eutectic (LBE) coolant. The EVEMP is an ideal alternative to the thermal-hydraulic system of non-refueling full-life micro reactors as it possesses no internal structures, such as impellors or sealing structures, for the transportation of LBE. Typically, the LBE passes through the annular flow channel of a reactor, is cooled by the heat exchanger, and then circulates back to the EVEMP flow channel. This thermal-hydraulic flow method is similar to natural circulation, which enhances thermal efficiency, while providing a golden time for cooling cores in the event of an emergency. When the forced circulation technology of the EVEMP was applied, the non-refueling full-life micro reactor achieve an output power of 60 MWt, which is higher than that achievable via the natural circulation method (30 MWt). Accordingly, an optimized EVEMP for Micro URANUS with a flow rate of 4196 kg/s and developed pressure of 73 kPa under a working temperature of 250 ℃ was designed.

• The Journal of Pediatrics of Korean Medicine
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• v.38 no.1
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• pp.1-9
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• 2024

Objective The purpose of this study was to confirm the effects of Galgeunhwanggeumhwangryeon-tang (PSCG) extract on skin moisturizing, antibacterial, and tight junction recovery in atopic dermatitis-induced mice. Methods In this study, we used 4-week-old NC/Nga mice divided into four groups: control (Ctrl), lipid barrier elimination (LBE), dexamethasone (Dx) after lipid barrier elimination (DEX), and PSCG after lipid barrier elimination (PSC). Ten rats were assigned to each treatment group. Three days after drug administration following lipid barrier elimination, ceramide kinase, caspase 14, sodium hydrogen antiporter (NHE), cathelicidin, claudin, and toll-like receptor (TLR)-2 were observed to confirm the restoration of skin moisturizer production, antimicrobial barriers, and tight junctions in the skin barrier. Results Ceramide kinase and caspase 14 positive reaction were significantly higher in PSC than in LBE and DEX. Both NHE and cathelicidin showed higher positive reactions in PSC than in LBE and DEX. Claudin, and TLR-2 showed higher levels of positive staining in the PSC group than in the LBE and DEX groups. Conclusion It was confirmed that the PSCG extract can have the potential to restore the damaged skin barrier in atopic dermatitis.

• The Journal of Pediatrics of Korean Medicine
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• v.35 no.4
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• pp.48-55
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• 2021

Objective The purpose of this study was to confirm the effects of Galgeunhwanggeumhwangryeon-tang in reducing inflammation through the endocannabinoid system (ECS) control in atopic dermatitis. Methods 8-week-old Balb/C mice were divided into 4 groups: contorl group (Ctrl), lipid barrier elimination group (ADE), palmitoylethanolamide treated group after lipid barrier elimination (PEA), and Galgeunhwanggeumhwangryeon-tang applied group after lipid barrier elimination (GGRT). After inducing atopic dermatitis, cannabinoid receptor (CB) 1, CB2, CD68, phosphorylated inhibitor kappa B (p-IκB), inducible nitric oxide synthase (iNOS), substance P and serotonin were observed to confirm the regulation of the ECS, macrophage activity and mast cell activity. Results CB1 and CB2 showed higher positive reactions in the GGRT than in the LBE and PEA. CD68, p-IκB and iNOS showed higher positive reaction in the LBE, PEA and GGRT than in the Ctrl, but the increase in the positive reaction was lower in the GGRT compared to the LBE and PEA. Substance P and serotonin showed higher positive reaction in the LBE, PEA and GGRT than in the Ctrl, but the increase in the positive reaction was lower in the GGRT compared to the LBE and PEA. Conclusions The effects of Galgeunhwanggeumhwangryeon-tang were confirmed though the regulation of the ECS, macrophage activity and mast cell activity.

• Corrosion Science and Technology
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• v.5 no.6
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• pp.201-205
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• 2006

HYPER(Hybrid Power Extraction Reactor) is the accelerator driven subcritical transmutation system developed by KAERI(Korea Atomic Research Institute). HYPER is designed to transmute long-lived transuranic actinides and fission products such as Tc-99 and I-129. Liquid lead-bismuth eutectic (LBE). Has been a primary candidate for coolant and spallation neutron target due to its appropriate thermal-physical and chemical properties, However, it is very corrosive to the common steels used in nuclear installations at high temperature. This corrosion problem is one of the main factors considered to set the upper limits of temperature and velocity of HYPER system. In this study, a parametric study for a corrosion model was performed. And a preliminary corrosion model was also developed to predict the corrosion rate in isothermal Pb and LBE flow loops.

• Korean Journal of Microbiology
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• v.24 no.4
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• pp.335-340
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• 1986

Two kind of ${\beta}-glucosidase$, tightly-bound enzyme(TBE) and loosely-bound enzyme(LBE), were obtained from the conidia of Aspergillus nidulans. The existence of enzymes in conidia was conformed by the fact that these enzyme activities were proportional to the number of conidia. The levels of enzyme activities were independent of aging of the conidia. Enzymes were characterized partially. In spite of the physical and chemical treatments of conidia, there was no significant change in TBE activity. The optimum pH and temperature was 6.0 and $55^{\circ}C$, respectively. Thermostability of the TBE was remarkably higher than that of mycelial ${\beta}-glucosidase$. The electrophoretic pattern of LBE was identical to that of mycelial ${\beta}-glucosidase$. These results suggest that conidial ${\beta}-glucosidase$ are involved in adaptation process of the conidia to variable environments.

• The Journal of Pediatrics of Korean Medicine
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• v.35 no.4
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• pp.156-166
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• 2021

Objectives The purpose of this study is to confirm the regulate effect of T helper (Th) 2 differentiation that Baekho-tang extract may produce to improves skin lipid barrier damages. Methods Four-weeks-old NC/Nga mice were divided into four groups: control group (Ctrl, n=10), lipid barrier eliminated group (LBE, n=10), Dexamethasone treatment after lipid barrier elimination group (DxT, n=10), and Baekho-tang extract treatment group after lipid barrier elimination group (BHTT, n=10). Baeko-tang extract was administered for 3 days after removal of the skin fat barrier in BHTT group. Then, we identified changes in external symptoms of the skin, factors affecting skin barrier such as potential of hydrogen (pH), filaggrin (FLG), transepidermal water loss (TEWL) and Th2 differentiation factors like Interleukin (IL)-4, Kallikrein Related Peptidase 7 (KLK7) and protease activated receptor 2 (PAR-2) through our immunohistochemistry. Results After lipid barrier elimination, the reduction of morphological skin inflammations was less in BHTT group than in LBE group and DxT group. Also, pH and TEWL were significantly decreased with BHTT group. However, FLG was significantly increased in BHTT group compared to LBE, DxT, and Ctrl group. All kinds of Th2 differentiation factors (IL-4, KLK7 and PAR-2) were also decreased in BHTT compared to the LBE and DxT. Conclusions As a result of this study, BHT administration decreased pH, TEWL, and increased FLG, thus participating in recovering damaged skin barrier. Since Th2 differentiation factors were decreased as well, BHT's regulatory effect in sequential immune reactions may be a possible explanation of how it enhances recovery of the damaged lipid barrier.

• The Journal of Pediatrics of Korean Medicine
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• v.36 no.1
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• pp.57-64
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• 2022

Objectives The purpose of this study is to confirm the regulate effect of T helper (Th) 2 differentiation that Sabaek-san extract may produce to improves skin lipid barrier damage. Methods Four-weeks-old NC/Nga mice were divided into four groups: control group (Ctrl, n=10), lipid barrier eliminated group (LBE, n=10), Dexamethasone treatment after lipid barrier elimination group (DXT, n=10), and Sabaek-san extract treatment group after lipid barrier elimination (SBT, n=10). Sabaek-san extract was administered for 3 d after removal of the skin fat barrier in SBT group. Then, we identified changes in external symptoms of the skin, factors affecting skin barrier such as potential of hydrogen (pH), filaggrin, transepidermal water loss (TEWL) and Th2 differentiation factors like Interleukin (IL)-4, Kallikrein Related Peptidase 7 (KLK7), and protease activated receptor 2 (PAR-2) through our immunohistochemistry. Results After lipid barrier elimination, the reduction of morphological skin inflammations was less in SBT group than in LBE and DXT group. Also, pH and TEWL were significantly decreased with SBT group. However, filaggrin was significantly increased in SBT group compared to LBE, DXT, and Ctrl group. All kinds of Th2 differentiation factors (IL-4, KLK7 and PAR-2) were also decreased in SBT compared to the LBE and DXT. Conclusions As a result of this study, SBT administration decreased pH, TEWL, and increased filaggrin, thus participating in recovering damaged skin barrier. Since Th2 differentiation factors were decreased as well, SBT's regulatory effect in sequential immune reactions may be a possible explanation of how it enhances recovery of the damaged lipid barrier.

• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.1972-1981
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• 2022

A typical ferritic/martensitic (F/M) steel sheet was subjected to pulsed laser surface remelting (LSR) and corrosion test in lead-bismuth eutectic (LBE) at 550 ℃. There present two modification zones with distinct microstructures in the LSRed specimen: (1) remelted zone (RZ) consisting of both bulk δ-ferrite grains and martensitic plates and (2) heat-affected zone (HAZ) below the RZ, mainly composed of martensitic plates and high-density precipitates. Martensitic transformation occurs in both the RZ and the HAZ with the Kurdjumov-Sachs and Nishiyama-Wassermann orientation relationships followed concurrently, resulting in scattered orientations and specific misorientation characteristics. Hardnesses of the RZ and the HAZ are 364 ± 7 HV and 451 ± 15 HV, respectively, considerably higher than that of the matrix (267 ± 3 HV). In oxygen-saturated and oxygen-depleted LBE, thicknesses of oxide layers developed on both the as-received and the LSRed specimens increase with prolonging corrosion time (oxide layers always thinner under the oxygen-depleted condition). The corrosion resistance of the LSRed F/M steel in oxygen-saturated LBE is improved, which can be attributed to the grain-refinement accelerated formation of dense Fe-Cr spinel. In oxygen-depleted LBE, the growth of oxide layers is very low with both types of specimens showing similar corrosion resistance.