• Journal of the Mineralogical Society of Korea
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• v.13 no.3
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• pp.164-170
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• 2000

Neutron single crystal and powder diffraction techniques have been applied to the structure analysis of yttria-stabilized zirconium, Z $r_{0.73}$ $Y_{0.27}$ $O_{1.87}$., prepared by the skull-melting method. The crystal structure has been determined to be cubic symmetry, space group Fm/equation omitted/ with a=5.155(2)$\AA$, V=136.99(5)$\AA$, Z=4, and R(F)=5.65%, $\omega$R(I)=10.57% for 70 integrated intensities of Bragg Peaks observed from single crystal of Z $r_{0.73}$ $Y_{0.27}$ $O_{1.87}$. The stabilizer atoms randomly occupy the zirconium sites and there are displacements of oxygen atoms with amplitudes of $\Delta$/a~0.033 and 0.11 along <110> and <100> directions from the ideal positions of the fluorite structure, respectively. There are no significant differences in crystallographic data between the single crystal and powder studies. Diffraction pattern after Rietveld refinement, using neutron powder data, has shown the evidence of a tetragonal impurity phase, or a slight tetragonal distortion.

• Journal of the Korean Society of Radiology
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• v.14 no.4
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• pp.447-453
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• 2020

This study accurately measured the half-life of the ¹⁷⁹Re radioactive isotope using the 100 MeV proton and high-purity HPGe gamma ray measurement system generated from a high-energy proton linear accelerator at the Korea Atomic Energy Research Institute. The result obtained is 19.64 ± 0.26 min. Compared with the past results of the half-life of the ¹⁷⁹Re radioisotope known to date, the results of B. Harmatz published in 1960 and B. J. Meijer published in 1975 measured the median value higher than the results obtained in this study. In the case of K. J. Hofstetter, published in 1966, a very large error is also characteristic. This result showed a tendency that the center value was very consistent with the result of this study. The results of Coral M. Baglin's 19.5 min published in 2009 are very consistent with the error range. The obtained measured result was compared with the result of ENSDF (Evaluated Nuclear Structure Data File). Through this study, more reliable values were measured for the results of the half-life of the ¹⁷⁹Re, which was previously incorrect, and the validity of the recently published results of Coral M. Baglin was confirmed.

• The Korean Journal of Nuclear Medicine Technology
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• v.12 no.3
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• pp.147-156
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• 2008

Purpose: All acts which are enforced from the radioactive iodine therapeutic team is a in its own way principle and provision. Therefore unification of all acts can not be appropriately. We will make the standard coherence. Materials & Methods: From 5 November, 2007 to 17 November 2007, we conducted a questionnaire survey of the nuclear medicine manager of 30 hospitals. The contents of a questionnaire is medical treatment section, patient management, prosecuting attorney section, waste management and safety supervision in about the patient and a questionnaire was drawn up in the method which selects an item. Results: 30 hospital agencies are operating purely for I-131 high dose ablation therapy. Diagnostic study and daily schedule had the difference of some. The most of education for the patients took charge of doctor and nurse. The satisfaction of education was evaluated as the high thing. The safety supervision of waste management accomplishment and Safety supervision the patient and the worker observed on the basis of atomic energy law. Conclusion: Specific standards with sufficient amount of information and practical contents should have been presented through the following data. However, it seems to be lacking in many aspects. Nevertheless, respondents rated 70.9%, which is relatively high, on the value of clinical utilization, and I am very thankful for the evaluation. For many years from now, it may seem necessary for a lot of research on the specific matters based on these data to be conducted.

• Korean Journal of Optics and Photonics
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• v.8 no.6
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• pp.445-449
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• 1997

The complex refractive indices of $Ge_2Se_2Te_5$ which show reversible phase change between the crystalline phase and an amorphous one depending upon the annealing process have been determined in the spectral range of 0.7-4.5 eV. The $Ge_2Se_2Te_5$ films were DC sputter deposited on the crystalline silicon substrate. The spectro-ellipsometry data of a thick film were analyzed following the modelling procedure where the quantum mechanical dispersion relation were used for the complex refractive indices of both the cryastalline phase $Ge_2Se_2Te_5$ and and amorphous phase $Ge_2Se_2Te_5$, respectively. On the other hand, with the surface micro-roughness layer whose effective thickness was determined from AFM analysis, the spectro-ellipsometry data were numerically inverted to yield the complex refractive index of $Ge_2Se_2Te_5$ at each wavelength. With these set of complex refractive indices, the reflectance spectra were calculated and those spectra obtained from the numerical inversion showed better agreement with the experimental reflection spectra for both the cryastalline phase and an amorphous phase. Finally, the thin $Ge_2Se_2Te_5$ film which has the optimum thickness of 26 nm as the medium for optical recording was also analyzed and the quantitative result of the film thickness and the surface microroughness has been reported.

• Archives of Pharmacal Research
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• v.28 no.7
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• pp.791-798
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• 2005

The hepatoprotective activity of flavonol glycosides rich fraction (F-2), prepared from 70% alcohol extract of the aerial parts of V calcarata Desf., was evaluated in a rat model with a liver injury induced by daily oral administration of $CCl_4$ (100 mg/kg, b.w) for four weeks. Treatment of the animals with F-2 using a dose of (25 mg/kg, b.w) during the induction of hepatic damage by $CCl_4$ significantly reduced the indices of liver injuries. The hepatoprotective effects of F-2 significantly reduced the elevated levels of the following serum enzymes: alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH). The antioxidant activity of F-2 markedly ameliorated the antioxidant parameters including glutathione (GSH) content, glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), plasma catalase (CAT) and packed erythrocytes glucose-6-phosphate dehydrogenase (G6PDH) to be comparable with normal control levels. In addition, it normalized liver malondialdehyde (MDA) levels and creatinine concentration. Chromatographic purification of F-2 resulted in the isolation of two flavonol glycosides that rarely occur in the plant kingdom, identified as quercetin-3,5-di-O-$\beta$-D-diglucoside (5) and kaempferol-3,5-di-O-$\beta$-D-diglucoside (4) in addition to the three known compounds identified as quercetin-3-O-$\alpha$-L-rhamnosyl- (${\rightarrow}6$)-$\beta$-D-glucoside [rutin, 3], quercetin-3-O-$\beta$-D-glucoside [isoquercitrin, 2] and kaempferol-3-O-$\beta$-D-glucoside [astragalin, 1]. These compounds were identified based on interpretation of their physical, chemical, and spectral data. Moreover, the spectrophotometric estimation of the flavonoids content revealed that the aerial parts of the plant contain an appreciable amount of flavonoids (0.89%) calculated as rutin. The data obtained from this study revealed that the flavonol glycosides of F-2 protect the rat liver from hepatic damage induced by $CCl_4$ through inhibition of lipid peroxidation caused by $CCl_4$ reactive free radicals.

• Nuclear Engineering and Technology
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• v.54 no.7
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• pp.2728-2735
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• 2022

The research on the flow and heat transfer characteristics of lead bismuth(LBE) is significant for the thermal-hydraulic calculation, safety analysis and practical application of lead-based fast reactors(LFR). In this paper, a new CFD model is proposed to solve the thermal-hydraulic analysis of LBE. The model includes two parts: turbulent model and turbulent Prandtl, which are the important factors for LBE. In order to find the best model, the experiment data and design of 19-pin hexagonal rod bundle with spacer grid, undertaken at the Karlsruhe Liquid Metal Laboratory (KALLA) are used for CFD calculation. Furthermore, the turbulent model includes SST k - 𝜔 and k - 𝜀; the turbulent Prandtl includes Cheng-Tak and constant (Pr_t =1.5,2.0,2.5,3.0). Among them, the combination between SST k - 𝜔 and Cheng-Tak is more suitable for the experiment. But in the low Pe region, the deviation between the experiment data and CFD result is too much. The reason may be the inlet-effect and when Pe is in a low level, the number of molecular thermal diffusion occupies an absolute advantage, and the buoyancy will enhance. In order to test and verify versatility of the model, the NCCL performed by the Nuclear Thermal-hydraulic Laboratory (Nuthel) of Xi'an Jiao tong University is used for CFD to calculate. This paper provides two verification examples for the new universal model.

• Proceedings of the Ginseng society Conference
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• 1980.09a
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• pp.87-113
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• 1980

This experiment was carried out to evaluate the effects of Korean ginseng extract on carcinogenesis induced by various chemical carcinogens. Red ginseng extract was used for this study and was administered orally to the experimental animals. Carcinogens that were injected in subscapsular region of ICR newborn mice within 24 hours after birth were 9,10-dimethyl-1,2-benzan-thracene (DMBA), urethane, N-2-fluorenylacetamide(AAF), aflatoxin $B_1$ and tobacco smoke condensate. N -methyl-N -nitroso-N'-nitroguani-dine(MNNG) was injected subcutaneously at the back of wistar rats. Experimental animals were autopsied in immediately after being sacrificed. All major organs were examined grossly and weighted. After fixation histopathological preparations were made for microscopical study. Following results were obtained. In DMBA group sacrificed at the 26th week after the treatment with DMBA, the incidence of lung adenoma was $77\%$ and the average number of the tumor was 17. However, in DMBA combined with red ginseng group, the incidence was $78\%$ and the average number of lung adenoma was 14.1. This indicates that ginseng extract had no effect on the incidence of lung adenoma but decreased the average number of lung adenoma by $17\%.$ In DMBA group sacrificed at the 48th week after the injection of DMBA, the lung adenoma incidence was $88\%.$ The average diameter of the largest lung adenoma was 3.5 cm, the incidence of diffuse pulmonary infiltration was $18\%$ and the average lung weight of male experimental mice was $528.2{\pm}469.1\;gm.$ On the other hand, in DMBA combined with red ginseng group sacrificed at the 48th week, the incidence of lung adenoma was $96\%.$ The average diameter of the largest adenoma was 2.7 cm, the incidence of diffuse pulmonary infiltration was $7\%$ and the average lung weight of male mice was $418.0{\pm}520\;gm.$ These observations show that ginseng extract did not have any inhibitory effect on the incidence of lung adenoma but decreased the average diameter of the largest lung adenoma by $23\%,$ the incidence of duffuse pulmonary infiltration by $63\%$ and the average lung weight of male experimental mice by $21\%.$ From these results we have found that the prolonged administration with ginseng extract showed no inhibitory effect on the incidence of adenoma but it had the inhibitory effect on the proliferation of lung adenomas induced by DMBA. In urethane group sacrificed at the 28th week after the injection of urethane, the incidence of lung adenoma was $94\%$ and the average number of lung adenoma was 8.6. In urethane combined with red ginseng group, the. incidence of lung adenoma was $73\%$ and the average number of adenoma was 6.0. These results indicate that there were $22\%$ decrease of the lung adenoma incidence and $31\%$ decrease of the average number of adenoma in urethane combined with red ginseng group. And in urethane group sacrificed at the 50th week, the incidence of lung adenoma was $98\%$ and the incidence of diffuse pulmonary infiltration was $14\%$. In urethane combined with ginseng group the incidence of lung adenoma was $85\%$ and the incidence of diffuse pulmonary infiltration was $12\%$. Therefore the ginseng administration resulted in $15\%$ decrease of the lung adenoma incidence and $14\%$ decrease of the diffuse pulmonary infiltration incidence. From these results we knew that the prolonged administration with ginseng extract inhibited the incidence and also the proliferation of the lung adenoma induced by urethane. Lung adenoma and hepatoma were induced in the experimental mice sacrificed at the 68th week but not in the experimental mice sacrificed at the 28th week after the injection of AAF. In AAF group sacrificed at the 68th week after the injection of AAF the incidence of lung adenoma was $18\%$ and the incidence of hepatoma was $27\%$. And in AAF combined with ginseng group the lung adenoma incidence was $12\%$ and the hepatoma incidence was $37\%$. So the ginseng seemed to decrease the lung adenoma incidence by AAF, but we were unable to conclude the significant inhibitory effect of the ginseng extract on the incidence of lung adenoma by AAF because the above incidence of lung adenoma were similar to that of control group which was $11\%$. And these experimental data revealed that ginseng extract didn't have any inhibitory effect on the incidence of hepatoma induced by AAF. In aflatoxin $B_1$ group sacrificed at the 56th week, the incidence of lung adenoma was $24\%$ and hepatoma was $11\%$. However in aflatoxin $B_1$ combined with ginseng group the incidence of lung adenoma was $17\%$ and hepatoma was $3\%$ These results indicate that there were $29\%$ decrease of the lung adenoma incidence and $75\%$ decrease of the hepatoma incidence in aflatoxin $B_1$ combined with ginseng group. In tobacco smoke condensate experimental group sacrificed at 67th week, no tumors were induced except just a few lung adenoma. The lung adenoma incidence both in tobacco smoke condensate group and in tobacco smoke condensate combined with ginseng group was $8\%$. And this incidence rate was similar to that of control group. These results indicate that the injection of 320 ug tobacco smoke condensate per ICR newborn mouse was unable to induce lung adenoma in our experiments. In MNNG group sacrificed at the 27th week the tumor incidence was $38.5\%$ and in MNNG combined with ginseng extract group was $37\%$. In MNNG group for investigation of the life span of tumor bearing rats the tumor incidence was $93\%$ and the average life span of tumor bearing rats was 318 days. And in MNNG combined with ginseng extract group the tumor incidence was $96\%$ and the average life span was 337 days. Tumor induced by MNNG was almost sarcoma. This indicates that there was no inhibitory effect of ginseng extract on the tumor incidence, but the extract prolonged the average life span of tumor bearing rats by approximately 19 days.

• Tunnel and Underground Space
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• v.28 no.5
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• pp.400-425
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• 2018

This study presents the research results and current status of the DECOVALEX-2019 project Task B. Task B named 'Fault slip modelling' is aiming at developing a numerical method to simulate the coupled hydro-mechanical behavior of fault, including slip or reactivation, induced by water injection. The first research step of Task B is a benchmark simulation which is designed for the modelling teams to familiarize themselves with the problem and to set up their own codes to reproduce the hydro-mechanical coupling between the fault hydraulic transmissivity and the mechanically-induced displacement. We reproduced the coupled hydro-mechanical process of fault slip using TOUGH-FLAC simulator. The fluid flow along a fault was modelled with solid elements and governed by Darcy's law with the cubic law in TOUGH2, whereas the mechanical behavior of a single fault was represented by creating interface elements between two separating rock blocks in FLAC3D. A methodology to formulate the hydro-mechanical coupling relations of two different hydraulic aperture models and link the solid element of TOUGH2 and the interface element of FLAC3D was suggested. In addition, we developed a coupling module to update the changes in geometric features (mesh) and hydrological properties of fault caused by water injection at every calculation step for TOUGH-FLAC simulator. Then, the transient responses of the fault, including elastic deformation, reactivation, progressive evolutions of pathway, pressure distribution and water injection rate, to stepwise pressurization were examined during the simulations. The results of the simulations suggest that the developed model can provide a reasonable prediction of the hydro-mechanical behavior related to fault reactivation. The numerical model will be enhanced by continuing collaboration and interaction with other research teams of DECOLVAEX-2019 Task B and validated using the field data from fault activation experiments in a further study.

• Economic and Environmental Geology
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• v.28 no.2
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• pp.109-121
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• 1995

The hydrothermal vein type deposits which comprise the Kasihan, Jompong and Gempol mineralized areas are primarily copper and zinc deposits, but they are also associated with lead and/or gold mineralization. The deposits occur within the Tertiary sedimentary and volcanic rocks in the Southern Mountain zone of the eastern Java island, Indonesia. Mineralization can be separated into two or three distinct stages (pre-and/or post- ore mineralization stages and main ore mineralization stage) which took place mainly along pre-existing fault breccia zones. The main phase of mineralization (the main ore stage) can be usually classified into three substages (early, middle and late) according to ore mineral assemblages, paragenesis, textures and their chemical compositions. Ore mineralogy and paragenesis of the three areas in the district are different from each other. Pyrite, pyrrhotite (/arsenopyrite), iron-rich (up to 20.5 mole % FeS) sphalerite and (Cu-)Pb-Bi sulfosalts are characteristic of the deposits in the Kasihan (/Jompong) area. On the other hand, pyrite + hematite + magnetite + iron-poor (2.7 to 3.6 mole % FeS) sphalerite assemblage is restricted to the Gempol area. Fluid inclusion data suggest that fluids of the main ore stage evolved from initial high temperatures (near $350^{\circ}C$) to later lower temperatures (near $200^{\circ}C$) with salinities ranging from 0.8 to 10.1 equiv. wt. percent NaCl. Each area represents a separate hydrothermal system: the mineralization at Kasihan and Jompong were largely due to early fluid boiling coupled with later cooling and dilution, whereas the mineralization at Gempol was mainly resulted from cooling and dilution by an influx of cooler meteoric waters. Fluid inclusion evidence of boiling indicates that pressures of ${\geq}95$ to 255 bars (${\geq}95$ bars for the Gempol area: $\approx$ 120 to 170 bars for the Jompong area: $\approx$ 140 to 255 bars for the Kasihan area) during portions of main ore stage mineralization. Equilibrium thermodynamic interpretation indicates that the evolution trends of the temperature versus fS2 variation of ore stage fluids in the Pacitan district follow two fashions: ore fluids at Kasihan and Jompong changed from the pyrite-pyrrhotite sulfidation stage towards pyritehematite- magnetite state, whereas those at Gempol evolved nearly along pyrite-hematite-magnetite reaction curve with decreasing temperature. The sulfur isotope compositions of sulfide minerals are consistent with an igneous source of sulfur with a ${\delta}^{34}S_{{\Sigma}s}$ value of about 3.3 per mil. The oxygen and hydrogen isotopic compositions of the fluids in each area indicate a progressive shift from the dominance of highly exchanged meteoric water at early hydrothermal systems towards an un- or less-exchanged meteoric water at later hydrothermal systems.

• Nuclear Engineering and Technology
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• v.28 no.2
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• pp.118-128
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• 1996

The lattice parameters of stoichiometric $UO_2$ and $U_{1-y}Er_{y}O_2$ in the range of y=0.01 to y =0.33 were determined with use of X-ray diffraction data. Oxygen potentials have been measured by means of a thermogravimetric method in the range of 1200~$1500^{\circ}C$ and $10^{-14}$ $\leq$ $Po_2$ $\leq$ $10^{-3}$ for pure $UO_2$ and $U_{1-y}Er_{y}O_{2{\pm}x}$ solid solutions with y=0.02, y=0.06 and y=0.20, respectively. Their oxygen partial pressures were maintained by controlling $CO_2$/CO mixture atmosphere, and the $Po_2$ values corresponding to x of $U_{1-y}Er_{y}O_{2{\pm}x}$ solid solutions were measured with an electrolyte oxygen sensor. The lattice parameter decreases linearly with an increase in the erbium content. The change of the lattice parameter can be expressed in a linear equation of y as a($\AA$) =5.4695-0.220y for 0 $\leq$y$\leq$0.33. The experimental coefficient of y -0.220 in $U_{1-y}Er_{y}O_2$ was an intermediate value between the calculated values -0.273 and -0.156 in the case of $U^{5+}$ and $U^{6+}$, respectively. The (equation omitted) has been found to undergo abrupt increase in the range of -360 to -270 kJ/mole for y=0.06 and -320 to -220 H/mole for y=0.20, respectively, in the temperature range of 1200-$1500^{\circ}C$. (equation omitted) increases with erbium content, but the effect of the dopant for x =0.01 is less significant than that for stoichiometry. The oxygen potentials for $UO_2$ and $U_{0.98}Er_{0.02}O_{2+x}$ can be approximately represented by the $U^{5+}$/$U^{4+}$ model but those for y$\geq$ 0.06 in $U_{1-y}Er_{y}O_{2{\pm}x}$ solid solutions cannot be interpreted by the mean uranium valence model.