• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.2
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• pp.137-164
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• 2018

The guarantee of the performance of the engineered barriers in a geological repository is very important for the long-term safety of disposal as well as the efficient design of the repository. Therefore, the performance of the engineered barriers under repository condition should be demonstrated by in-situ experiments conducted in an underground research laboratory. This article provides a review of the major in-situ experiments that have been carried out over the past several decades at underground research laboratories around the world to validate the performance of engineered barriers of a repository, as well as their results. In-situ experiments to study the coupled thermal-hydraulic-mechanical behavior of the engineered barrier system used to simulate the post-closure performance of the repository are analyzed as a priority. In addition, in-situ experiments to investigate the performance of the buffer material under a real repository environment have been reviewed. State-of-the art in-situ validations of the buffer-concrete interaction, and the installation of the buffer, backfill and plug, as well as characterization of the near-field rock and the corrosion of the canister materials are, also performed.

• Journal of the Korean institute of surface engineering
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• v.41 no.3
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• pp.83-87
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• 2008

This study described the effects of RF power, DC bias voltage, chamber pressure and gas mixing ratio on the etch rates of TiN thin film and selectivity of TiN thin film to $SiO_2$ with $BCl_3$/Ar gas mixture. When the gas mixing ratio was $BCl_3$(20%)/Ar(80%) with other conditions were fixed, the maximum etch rate of TiN thin film was 170.6 nm/min. When the DC bias voltage increased from -50 V to -200 V, the etch rate of TiN thin film increased from 15 nm/min to 452 nm/min. As the RF power increased and chamber pressure decreased, the etch rate of TiN thin film showed an increasing tendency. When the gas mixing ratio was $BCl_3$(20%)/Ar(80%) under others conditions were fixed, the intensity of optical emission spectra from radical or ion such as Ar(750.4 nm), $Cl^+$(481.9 nm) and $Cl^{2+}$(460.8 nm) was highest. The TiN thin film was effectively removed by the chemically assisted physical etching in $BCl_3$/Ar ICP plasma.

• Nuclear Engineering and Technology
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• v.42 no.1
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• pp.79-88
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• 2010

Spent $UO_2$ nuclear fuel discharged from a nuclear power plant (NPP) contains fission products, U, Pu, and other actinides. Due to neutron capture by $^{238}U$ in the rim region and a temperature gradient between the center and the rim of a fuel pellet, a considerable increase in the concentration of fission products, Pu, and other actinides are expected in the pellet periphery of high burnup fuel. The characterization of the radial profiles of the various isotopic concentrations is our main concern. For an analysis, spent nuclear fuels originating from the Yeonggwang-2 pressurized water reactor (PWR) were chosen as the test specimens. In this work, the distributions of some actinide isotopes were measured from center to rim of the spent fuel specimens by a radiation shielded laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS) system. Sampling was performed along the diameter of the specimen by reducing the sampling intervals from 500 ${\mu}m$ in the center to 100 ${\mu}m$ in the pellet periphery region. It was observed that the isotopic concentration ratios for minor actinides in the center of the specimen remain almost constant and increase near the pellet periphery due to the rim effect apart from the $^{236}U$ to $^{235}U$ ratio, which remains approximately constant. In addition, the distributions of local burnup were derived from the measured isotope ratios by applying the relationship between burnup and isotopic ratio for plutonium and minor actinides calculated by the ORIGEN2 code.

• Natural Product Sciences
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• v.22 no.2
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• pp.93-101
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• 2016

For efficient quality control of the Samryeongbaekchul-san decoction, a powerful and accurate an ultra-performance liquid chromatography (UPLC) coupled with electrospray ionization (ESI) tandem mass spectrometry (MS) method was developed for quantitative analysis of the thirteen constituents: allantoin (1), spinosin (2), liquiritin (3), ginsenoside Rg1 (4), liquiritigenin (5), platycodin D2 (6), platycodin D (7), ginsenoside Rb1 (8), glycyrrhizin (9), 6-gingerol (10), atractylenolide III (11), atractylenolide II (12), and atractylenolide I (13). Separation of the compounds 1 - 13 was performed on a UPLC BEH $C_{18}$ column ($2.1{\times}100mm$, $1.7{\mu}m$) at a column temperature of $40^{\circ}C$ with a gradient solvent system of 0.1% (v/v) formic acid aqueous-acetonitrile. The flow rate and injection volume were 0.3 mL/min and $2.0{\mu}L$. Calibration curves of all compounds were showed good linearity with values of the correlation coefficient ${\geq}0.9920$ within the test ranges. The values of limits of detection and quantification for all analytes were 0.04 - 4.53 ng/mL and 0.13 - 13.60 ng/mL. The result of an experiment, compounds 2, 6, 12, and 13 were not detected while compounds 1, 3 - 5, and 7 - 11 were detected with 1,570.42, 5,239.85, 299.35, 318.88, 562.27, 340.87, 12,253.69, 73.80, and $115.01{\mu}g/g$, respectively.

• Natural Product Sciences
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• v.14 no.4
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• pp.274-280
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• 2008

Platycosides are the saponins in Platycodi Radix and they have several beneficial effects such as antiinflammatory and anti-obesity activities. This study was designed to determine the changes in the saponin composition in Platycodi Radix (platycosides) after being processed under steam and pressure and to investigate the anti-inflammatory effects of their extracts. The change of the platycoside compositions was investigated after 1, 2, 3, 6 and 9h heat processing of Platycodi Radices by using HPLC coupled with an evaporative light scattering detection (ELSD) system. After heat treatment ($125^{\circ}C$, 1, 2, 3, 6 and 9 h), the contents of several platycosides such as platycoside E, platycodin $D_3$, platycodin D, polygalacin D, and platycodin A decreased as the processing time was longer. While the total contents of the saponins decreased, the contents of deapi-forms of deapiplatycoside E, deapi-platycodin $D_3$, and deapi-platycodin D increased relatively. These results indicate that the linkage between apiose and xylose located at C-28 is labile to heat and pressure. The LPS-induced iNOS inhibitory activities of the samples treated for 1 and 2 hours were enhanced and after then, the activities were reduced. These results suggested that heat treatment of the samples affect the content of the total saponins and the saponin content may be the important criteria representing the anti-inflammatory activity.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.92-92
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• 2012

경안천은 팔당호로 직접 유입되는 하천 중 유입량 대비 오염도가 매우 높아 상수원보호를 위한 특별관리가 요구되는 지역이다. 또한 경안천 유역은 수도권과 인접하고 있어, 도시화에 의해 토지이용이 지속적으로 변화되고 있다. 이러한 토지이용의 변화는 불투수면적을 증가시켜 강우시 유출 및 수질오염 발생량을 증가시킨다. 그러므로 불투수면적 증가에 따른 영향을 줄이기 위해서는 친환경 도시개발에 적용하고 있는 LID기법을 도입하여, 개발지역의 불투수면적 발생을 최소화하여야 하며 오염원 발생을 사전에 제어해야 한다. 그러나 도시개발시 무분별한 LID기법 도입은 정부의 막대한 예산 및 인력낭비를 초래하므로 현장적용 전 모델링을 통해 LID기법의 기대효과 및 비용을 산출하여야 하며, 도시 계획 수립시 가장 효과적인 LID기법을 제시하여야 한다. 따라서 효과적인 LID기법을 제시하기 위해서는 LID기법 평가가 가능한 SWMM모형을 이용해야 한다. 하지만 경안천 유역과 같이 유역 내 도시 와 비도시지역이 혼재되어 있는 우리나라의 대부분의 유역은 SWMM모형만으로는 유역의 강우-유출 및 수질 평가가 불가능하기 때문에, 유역 내 도시와 비도시지역의 유출 및 수질관리 평가가 가능한 SWAT-SWMM 연계모델을 이용하여 유출량 및 수질관리 효과를 분석해야 한다. 본 연구에서는 SWAT-SWMM 연계모델을 이용하여 LID기법 별 시나리오를 구축하였고, 시나리오별 유출량 및 수질오염 발생량을 모의하여 분석하였다. 분석결과 상당량의 유출량 저감 및 수질개선 효과가 나타났다. 또한 SWAT-SWMM 연계모델을 이용하여 모의된 수질자료는 환경부에서 제시하고 있는 단위유역 대표지점 수질환경기준 달성의 객관적인 평가를 가능하게 한다. 향후 LID를 적용한 SWAT-SWMM 연계모델을 이용하여 정부에서 규제하는 개발제한구역이 포함된 유역에서의 도시개발시 수질환경기준에 맞는 친환경적인 개발을 할 수 있을 것이라 기대된다.

• Membrane Journal
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• v.25 no.6
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• pp.503-514
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• 2015

In this study, water purification system without coagulant was consisted of F/A and membrane to produce purified water which only uses physical treatment without coagulant. Because the use of coagulant has a possibility remaining of hazardous aluminum with our health. Especially, the Filtralite was reviewed the possibility to remove turbidity and organic material. It was found that the turbidity removal rate of Filtralite was 83~84%. It show that Filtralite has similar efficiency to sand-filter. But Filtralite has higher 50% removal rate of organic material than sand-filter due to well-developed pore on the surface of it. So, Filtralite could be used to substitute the sand-filter for the F/A process due to higher removal rate. And also coupled with activated carbon in F/A process, TMP was increased by TOC value. To prevent increasing TMP, media that has outstanding organic adsorption ability should be used.

• The Journal of Pediatrics of Korean Medicine
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• v.34 no.4
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• pp.11-21
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• 2020

Objectives This study aimed to investigate the efficacy of Ephedra sinica (E. sinica), Panax ginseng (P. ginseng), and Alisma orientale (A. orientale) Extract (MIT) on insulin resistance induced by Non-alcoholic fatty liver disease (NAFLD). Methods C57BL /6 male mice (8-week-old, 20 g) were divided into four groups: control group (Ctrl), high-fat diet group (HFDF), high fat diet with metformin administration group (METT), and high fat diet with MIT administration group (MITT). Each 10 mice were allocated to each group (a total of 40 mice). All mice were allowed to eat fat-rich diet freely throughout the experiment. To examine the effect of MIT, we observed Cannabinoid receptor type 1 (CB1), Cannabinoid receptor type 2 (CB2), G protein-coupled receptor 55 (GPR55), and Transforming growth factor-β (TGF-β). Results In the MITT group, positive reactions of the CB1, CB2, and GPR55 were significantly was significantly suppressed compared to the HFDF group. The positive reactions of the CD36 and TGF-β in the liver tissue were significantly suppressed in MITT. Conclusions MIT has the effect of improving NAFLD induced insulin resistance through the regulation of the lipid metabolism.

• Biomolecules & Therapeutics
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• v.10 no.4
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• pp.293-302
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• 2002

The classical concept for iron uptake into mammalian cells has been the endocytosis of transferrin( $T_{f}$ )-bound F $e^{3+}$ via the $T_{f}$ - $T_{f}$ receptor cycle. In this case, we could not explain the uptake of F $e^{2＋}$ ion and the export of iron from endosome. Studies on iron transport revealed that other transport system exists in epithelial cells of the intestine. One of non- $T_{f}$ -receptor-mediated transport systems is Nramp2/DMT1/DCT1 which transports M $n^{＋＋}$, $Mg^{＋＋}$, Z $n^{＋＋}$, $Co^{＋＋}$, N $i^{＋＋}$ or C $u^{＋＋}$ ion as well as F $e^{+2}$ ion. DMT1 was cloned from intestines of iron-deficient rats and shown to be a hydrogen ion-coupled iron transporter and a protein regulated by absorbed dietary iron. DMT1 is founded in other cells such as cortical and hippocampal glial cells as well as endothelial cells in duodenum. Two F $e^{3+}$ ion bound to transferrin( $T_{f}$ ) are taken up via the $T_{f}$ - $T_{f}$ receptor cycle in the intestinal epithelial cell. F $e^{3+}$ in endosome was converted to F $e^{2＋}$ ion, and then exported to cytosol via DMT1. F $e^{2＋}$ ion is taken up into cytosol via DMT1. Several other transporters such as FET, FRE, CCC2, AFT1, SMF, FTR, ZER, ZIP, ZnT and CTR have been reported recently and dysfunction of the transporters are related with diseases containing Wilson's disease, Menkes disease and hemochromatosis. Evidences from several studies strongly suggest that DMT1 is the major transporter of iron in the intestine and functions critically in transport of other metal ions.

• Journal of the korean society of oceanography
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• v.39 no.4
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• pp.234-242
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• 2004

The pigment composition and concentration of phytoplankton assemblages using HPLC in the adjacent waters of four nuclear power plants (Yonggwang, Kori, Wolsong and Ulchin) were investigated during the spring blooming in 2004. The mean concentration of chlorophyll a ranged from 563.8 to 2,949.0ng $l^{-1}$, with the lowest concentration at Kori and the highest concentration at Wolsong. Among the carotenoids, the amounts of fucoxanthin and chlorophyll $C_2$ were relatively higher than those of other pigments in the study site. As minor pigments, zeaxanthin, chlorophyll b, 19'-butanoyloxyfucoxanthin, diadinoxanthin, 19'-hexanoyloxyfucoxanthin, chlorophyll $C_3$ and peridinin were detected. The results of pigment composition and concentration showed that diatoms had an important proportion of phytoplankton community when a spring bloom occurred. Cyanobacteria was present relatively low density at the Wolsong and the green alga such as chlorophytes and prasinophytes were abundant at the Yonggwang and Kori, while dinoflagellates characterized by peridinin were common at Ulchin and Kori. The pigment composition and concentration of phytoplankton after passing through the cooling-water system of nuclear power plant were highly variable. No distinct trend of the change of each pigment composition and amount was detected but the variation of fucoxanthin and chlorophyll $C_2$ highly coupled with that of chlorophyll a. We pointed out that the diatom controlled the overall variation of phytoplankton biomass during the spring season.