• Journal of Korean Society of Water and Wastewater
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• v.19 no.1
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• pp.53-60
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• 2005

Ferrous cement hydrates made from hydrating Portland cement doped with Fe (II) were reported to reductively dechlorinate chlorinated organics and to reduce Cr (VI) to Cr (III). In this study, kinetics of nitrate removal by ferrous cement hydrates were investigated. Nitrate removal kinetics were characterized by experimental variables such as cement hydration, amount of cement addition, Fe (II) dose, pH, and byproducts. As a result, hydrated cement showed better performances than non-hydrated cement due to the formation of LDH (layered double hydroxide). Doping of Fe (II) into the cement was found to improve removal efficiency at high pHs by association with Fe (II) sorbed on cement hydrates as a reactive reductant. Reduction of nitrate produced ammonium as a major product, which accounted for 63.5% of the final products, and nitrite (0.15%) as a minor product. These results indicate that the developed media are effective as sorbent/reducing agents in the nitrate removal and the reaction mechanisms of nitrate removal are sorption and reduction.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1221-1227
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• 2011

Ethyl pyruvate (EP) is known as a scavenger of reactive oxygen species (ROS) in the body through its role in the donation of diketone groups to metals to form an EP-metal complex. In order to develop a method for the quantification of EP in biological media, a sensitive and specific, high-performance liquid chromatographyelectrospray ionization-mass spectrometry (HPLC-ESI/MS) method is used to determine the EP-alkali metal ion binding species. The analyte was separated on a ZORBOX SB-C8 ($3.5{\mu}m$, $30mm{\times}2.1mm$ I.D.) column and analyzed in selected ion monitoring (SIM) mode with a positive ESI interface using the m/z 255 $[2M + Na]^+$ ion. The method was validated over the concentration range of $0.5-60.0\;{\mu}g$/mL under 1/9 (v/v) of acetonitrile/methanol solvent system with flow rate 0.05 mL/min. The limit of quantification (LOQ) was $0.5{\mu}g$/mL.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.3
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• pp.390-397
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• 2013

Primary-cultured immune cells are widely used in research to elucidate the mechanism of inflammation including chemotaxis, production of reactive oxygen species, cytokine release and antigen presenting. Mice are one of the species of experimental animals commonly used for such studies. Immune cells can be isolated and cultured from various organs such as bone marrow, peritoneal cavity, lung, spleen. For elaborated experimental studies, immune cells should be elicited with inflammatory substances or proliferated in vitro with special media. This paper details methods of obtaining immune cells from various organs of mice and investigating immune mechanism using isolated immune cells. It contains standard protocols of isolating and culturing immune cells from bone marrow, peritoneal cavity and lymphoid organs. It also covers the methods of investigating immune mechanism such as ELISA, western blotting, confocal microscopy and ELISPOT assay. With the works in this study, we established the standardized isolation and analysis methods of primary-cultured immune cells.

• Journal of Powder Materials
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• v.10 no.6
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• pp.430-435
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• 2003

The phenomenon of electrical explosion of conductors is considered in the context of the changes in the energy and structural states of the metal at the stages of energy delivery and relaxation of the primary products of EEC. It is shown that these changes are related to the forced interaction of an intense energy flux with matter and to the subsequent spontaneous relaxation processes. The characteristics of nano-sized metal powders are also discussed. The preferential gas media during EEC is Ar+$H_2$. An increase in $e/e_s$ (in the range of values studied) leads to a reduction in the metal content. For reactive powders obtained with high metal content, it is necessary to separate the SFAP fractions, which settled on the negative electrode of the electric filter.

• Microbiology and Biotechnology Letters
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• v.27 no.6
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• pp.500-508
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• 1999

Several white-rot fungi collected from the mountains of Korea were evaluated for their ability to decolorize azo, polymeric, and reactive dyes. Strains CJ-105, CJ-212 and CJ-315, identified as Trametes sp., Pleurotus sp. and Fomes sp., respectively, showed higher potential for decolorization of those dyes in either solid or liquid media. For Trametes sp. CJ-105, 100ppm of Remazol Brilliant blue R and 500ppm of Acid Red 264 were completely decolorized after 2 days under liquid culture. The dominating ligninolytic enzyme existing in the culture broth was laccase (E.C. 1.10.3.2). Also, Pleurotus sp. CJ-212 and Fomes sp. CJ-315 showed similar patterns in decolorization of Remazol Brilliant Blue R and Acid Red 264. The extent of decolorization of the dyes in liquid culture was found to be proportional to the activities of the ligninolytic of decolorization of the dyes in liquid culture was found to be proportional to the activities of the ligninolytic enzymes produced by each strain. In addition to that Trametes sp. CJ-105 was highly effective in degradation of polycyclic aromatic hydrocarbons and pentachlorophenol by the activity of the ligninolytic enzymes produced. In this study, we found that white-rot fungi, Trametes sp. CJ-105(KFCC 10941), Pleurotus sp. CJ-212(KFCC 10943) and Fomes sp. CJ-315(KFCC 10942), were effective in decolorizing a wide range of structurally different synthetic dyes, as well as some chemical compounds which are known to be hardly degradable.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.629-631
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• 2013

In many enterprises, fraudulent activities and processes are widely prevalent. But, their employees would not report the illegal activities since they would be attacked by defensive and reactive retaliations in their enterprises. Against this backdrop, we design notification systems for whistle blowing. The design would certainly be useful for fraudulent process notification while using management information systems in the field of business. The fraudulent process notification is related to whistle blowing systems, methods, storage media, and so on. Also, we establish the whole architecture of fraudulent process notification with functional structure from the viewpoint of systems and whistle blower. The flow diagram of notification method is added.

• Journal of Microbiology
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• v.44 no.3
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• pp.269-275
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• 2006

Atmospheric-pressure cold plasma (APCP) using helium/oxygen was developed and tested as a suitable sterilization method in a clinical environment. The sterilizing effect of this method is not due to UV light, which is known to be the major sterilization factor of APCP, but instead results from the action of reactive oxygen radicals. Escherichia coli, Staphylococcus aureus, and Saccharomyces cerevisiae deposited on a nitrocellulose filter membrane or Bacillus subtilis spores deposited on polypropylene plates were exposed to helium/oxygen plasma generated with AC input power at 10 kHz, 6 kV. After Plasma treatment, nitrocellulose filter membranes were overlaid on fresh solid media and CFUs were counted after incubation overnight. D-values were 18 sec for E. coli, 19 sec for S. aureus, 1 min 55 sec for S. cerevisiae, and 14 min for B. subtilis spores. D-values of bacteria and yeast were dependent on the initial inoculation concentration, while the D-value of B. subtilis spores showed no correlation. When treated cells were observed with a scanning electron microscope, E. coli was more heavily damaged than S. aureus, S. cevevisiae exhibited peeling, and B. subtilis spores exhibited shrunken morphology. Results showed that APCP using helium/oxygen has many advantages as a sterilization method, especially in a clinical environment with conditions such as stable temperature, unlimited sample size, and no harmful gas production.

• YAKHAK HOEJI
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• v.43 no.5
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• pp.598-605
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• 1999

The hot water and mathanol extracts of Artemisia argyi showed considerable cytotoxicities against H9(ATCC HTB 176) cancer cell with IC50 values of $48.6{\;}\mu\textrm{g}/ml$ and $51.9{\;}\mu\textrm{g}/ml$, respectively. These cytotoxicities were found to be dependent on the extract concentrations and culture days. CuZnSOD and MnSOD activities were significantly increased in the cytoplasm and mitochondria fractions of cancer cell, and media in the presence of Artemisia argyi. Such enhanced SOD activities were generally in the range of two to threefolds. In contrast to SOD, catalase and glutathione peroxidase activities were not detected at all. These results suggest that Artemisia argyi have generated $O_2^-$ in the mitochondria and cytoplasm of H9 cancer cell with concurrent induction of CuZnSOD and MnSOD in situ, which dismutate $O_2^-{\}to{\;}H_2O_2$. Without coordinated actions of catalase and/or glutathione peroxidase $H_2O_2$ is easily converted to very toxic OH and these reactive oxygen species together might have induced necrosis and/or apoptosis of H9 cell.

• Journal of agriculture & life science
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• v.46 no.2
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• pp.115-127
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• 2012

Antioxidant and neuronal cell protective effects of aqueous extract from lotus (Nelumbo nucifera) leaf tea (LLTE) were investigated. The 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) radical scavenging effect, ferric reducing antioxidant power, and malondialdehyde inhibition of LLTE were increased in a dose dependent manner. Intracellular reactive oxygen species accumulation resulting from hydrogen peroxide ($H_2O_2$) treatment was significantly reduced when LLTE were present in the media compared to PC12 cells treated with $H_2O_2$ only. In neuronal cell viability assay using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide (MTT), LLTE showed protective effect against $H_2O_2$-induced neurotoxicity. In addition, lactate dehydrogenase release into medium was also inhibited by LLTE (7.13-43.89%). Total phenolics of LLTE were 33.16 mg/g and a quercetin was identified as major phenolics (105.93 mg/100g). Therefore, above these data suggest that LLTE including quercetin may be useful in the natural antioxidant substance, and may reduce the risk of neurodegenerative disease.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.601-605
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• 1995

Magnetic properties of FeTaN and FeTaC films deposited by DC magnetron reactive sputter were investigated, and correlated with their microstructures. The optimum magnetic properties of Hc : 0.25 Oe, Bs : 14.5 kG, and ${\mu}'$ : 4000 (5MHz) are observed in the $Fe_{78.8}Ta_{8.5}N_{12.7}$ film, and Hc : 0.25 Oe, Bs : 14.5 kG, and ${\mu}'$ : 2700 (5MHz) in the $Fe_{75.6}Ta_{8.1}C_{16.3}$ film. In both FeTaN and FeTaC films with minimum grain size show the best soft magnetic properties. Thermal stability of the soft magnetic properties of FeTaN is found to be higher than FeTaC for similar compositons. TaN and TaC particles form to retard the growth of $\alpha$-Fe grains. TaN particles in FeTaN show higher efficiency in retarding the grain growth during heat treatments resulting the higher thermal stability, compared to TaC particles in FeTaC films.