• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1463-1474
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• 2008

In order to investigate stabilization effect and sustainability on As-contaminated farmland soils which were affected the abandoned mine site and stabilized by zerovalent iron(ZVI) and industrial by-products, batch-scale and pilot-scale tests were carried out. In batch tests, ZVI and industrial by-products(blast furnace slag, steel refining slag and oyster shell powder) were used in treatment materials to reduce the As leaching. Industrial by-products were mixed with As-contaminated soils, in the ratio of 1%, 3%, 5% and 7% on the weight base of dried soil. The results of batch-scale tests was shown that the reduction of As concentration was observed in all samples and it was expected that ZVI and steel refining slag were more effective than other treatment materials to stabilize As compounds. In pilot-scale tests, columns were filled with untreated soils and treated soils mixed with ZVI and steel refining slag in the same mixing ratio of 3%. Distilled water was discharged into the columns with the velocity of 0.3 pore volume/day. During the test, pH, EC, Eh and As concentration were measured in the regular term(1pore volume). after six months, pilot-scale tests were retested to investigate sustainability of treatment materials. As a result, It was shown that the leachate from control column was continuously released during the test period and its concentration was greater than $100ug{\cdot}L^{-1}$ which was exceeded the national regulation of water discharged to river or stream ($50ug{\cdot}L^{-1}$). On the other hand, soil treated with ZVI and steel refining slag showed that the concentrations of leachate were lower than national regulation of water discharged to river or stream. Therefore it was expected that ZVI and steel refining slag could be applied to the farmland site as the alternative treatment materials.

• Economic and Environmental Geology
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• v.53 no.6
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• pp.687-694
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• 2020

Two oxidizing agents (KMnO4, H2O2), and one neutralizing agent (NaOH) were applied to evaluate Mn removal in mine drainage. A Mn2+ solution and artificial mine drainage were prepared to identify the Fe2+ influence on Mn2+ removal. The initial concentrations of Mn2+ and Fe2+ were 0.1 mM and 1.0 mM, respectively. The injection amount of oxidizing and neutralizing agents were set to ratios of 0.1, 0.67, 1.0, and 2.0 with respect to the Mn2+ mole concentration. KMnO4 exhibited a higher removal efficiency of Mn2+ than did H2O2 and NaOH, where approximately 90% of Mn2+ was removed by KMnO4. A black MnO2 was precipitated that indicated the oxidation of Mn2+ to Mn4+ after an oxidizing agent was added. In addition, MnO2 (pyrolusite) is a stable precipitate under pH-Eh conditions in the solution. However, relatively low removal ratios (6%) of Mn2+ were observed in the artificial mine drainage that included 1.0 mM of Fe2+. The rapid oxidation tendency of Fe2+ as compared to that of Mn2+ was determined to be the main reason for the low removal ratios of Mn2+. The oxidation of Fe2+ showed a decrease of Fe concentration in solution after injection of the oxidizing and neutralizing agents. In addition, Mn7+ of KMnO4 was reduced to Mn2+ by Fe2+ oxidation. Thus, the concentrations of Mn increased in artificial mine drainage. These results revealed that the oxidation method is more effective than the neutralization method for Mn removal in solution. It should also be mentioned that to achieve the Mn removal in mine drainage, Fe2+ removal must be conducted prior to Mn2+ oxidation.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.162-167
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• 2004

In this study, untreated (UT), water soaking (WT), and sanitizing solutions [chlorine at 100 ppm (CL): ethanol at 10% (ET); hydrogen peroxide at 1% (HP); chlorine at 100 ppm + ethanol at 10%(CE); chlorine at 100 ppm + hydrogen peroxide at 1% (CH); ethanol at 10% + hydrogen peroxide at 1% (EH); chlorine at 100 ppm + ethanol at 10% + hydrogen peroxide at 1% (CEH)] were compared in terms of their antimicrobial effectiveness against natural microflora of wild cabbage (Brassica oleracea var. capitata). All samples were kept in sanitizing solutions for 2 min, and effectiveness of sanitizing agents was evaluated based on number of decimal reduction of total aerobic mesophilic, total coliforms, E. coli, lactic acid bacteria, and yeast and mold counts. Average initial levels of these organisms in samples were $9.21{\pm}0.15,\;6.60{\pm}0.06,\;6.08{\pm}0.03,\;and\;3.66{\pm}0.08\;log_{10}\;CFU/g$ for total aerobic mesophilic bacteria, total coliforms, lactic acid bacteria, and yeasts and molds, respectively, Escherichia coli was not detected in any tested samples. Decimal reduction of populations of total aerobic mesophilic, total coliforms, E. coli, lactic acid bacteria, and yeasts and molds were: in $WT\;8.09,\;5.36,\;5.82,\;and\;3.57 log_{10}\;CFU/g;\;in \;CL\;7.39,\;4.10\;5.24,\;2.45\;log_{10}\;CFU/g;\;in\;ET\;6.78,\;4.23,\;5.20,\;2.50\;log_{10}\;CFU/g;\;in\;HP\;6.11,\;4.27,\;5.28,\;2.46\;log_{10}\;CFU/g;\;in\;CE\;6.18,\;4.26,\;5.31,\;2.49\;log_{10}\;CFU/g;\;in\;CH\;6.10,\;3.77,\;5.33,\;2.46\;log_{10}\;CFU/g;\;in\;EH\;6.07\;3.82,\;4.76,\;2.41\;log_{10}\;CFU/g;\;and\;in\;CEH\;5.27,\;3.45,\;4.45,\;2.15\;log_{10}\;CFU/g,$ respectively. Statistical analysis of the results showed effectiveness of CEH sanitizing solution for elimination of microbial contamination was the highest among all sanitizer treatments.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.228-234
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• 1993

Seedling emergence of 15 rice varieties (Gayabyeo, Chilseongbyeo, Samgangbyeo, Yeongsanbyeo, Yeongdeugbyeo, Hwajinbyeo, Palgongbyeo, Seomjinbyeo, Tamjinbyeo, Milyang 95, M 101, M 202, Newbonnet, Tebonnet, and Lemont) were tested at different soil moisture regimes and seeding depths. Submergence for four days immediately after seeding did not reduce emergence rate in all varieties. Under the flooded condition, the percentage of emergence of all varieties at 1.5cm seeding depth ranged 0～40%, it is much lower compared to uncovered control, and percentage of seedling survival ranged 0～24% due to death of some emerged seedlings. Under the field condition, one time flooding up to 10cm above the soil surface after seeding did not reduce the percent emergence of seedlings. The pF value of soil was 0 for few days after flooding or raining and Eh of soil ranged 443-453m V.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.9
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• pp.803-809
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• 2005

Cerium ammonium nitrate (CAN) and nitric acid was used an etchant and an additive for Ru etching and polishing. pH and Eh values of the CAN and nitric acid added chemical solution satisfied the Ru etching condition. The etch rate increased linearly as the concentration of CAN increased. Nitric acid added solution had the high etch rate. But micro roughness of etched surfaces was not changed before and after etching, The removal rate of Ru film was the highest in $1wt\%$ abrasive added slurry, and not increased despite the concentration of alumina abrasive increased to $5wt\%$. Even Ru film was polished by only CAN solution due to the friction. The highest removal rate of 120nm/min was obtained in 1 M nitric acid and $1wt\%$ alumina abrasive particles added slurry. The lowest micro roughness value was observed in this slurry after polishing. From the XPS analysis of etched Ru surface, oxide layer was founded on the etched Ru surface. Therefore, Ru was polished by chemical etching of CAN solution and oxide layer abrasion by abrasive particles. From the result of removal rate without abrasive particle, the etching of CAN solution is more dominant to the Ru CMP.

• Journal of the Korean Society of Tobacco Science
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• v.28 no.2
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• pp.117-123
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• 2006

The pulping process in a papermaking process for a reconstituted tobacco sheet (RECON) was evaluated. For the practical information, the experiments were conducted in a real mill. Two pulping conditions were chosen and changed depending on the feasibility, such as the pulping temperature and the properties of pulping water. The higher pulping temperature resulted in the easier dissolution of solubles from the raw materials. However, the efficiency of screw press process was decreased by the higher pulping temperature, which resulted in the reduction of the HWS and the concentration in the #1 screw press filtrate. The addition of SEL(Strong extracted liquor) to pulper affected the efficiency of dissolution and the final concentration of #1 screw press filtrate. Although the higher SEL resulted in the less dissolution of the solubles from the raw materials, the concentration of the #1 screw press filtrate was greatly increased by the higher addition of SEL, which could provide much better efficiency to the following evaporation process of the filtrate and could increase the whole productivity.

• Preventive Nutrition and Food Science
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• v.6 no.1
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• pp.66-72
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• 2001

Ginseng may have antioxidant and pharmacologic effects similar to those of vitamin E. The interactive effect of ginseng and vitamin E was studied with respect to cholesterol metabolism and the antioxidant status. A ginseng supplement (0.1%, wt/wt) with comparable levels of vitamin E was provided with a high-cholesterol (1%, wt/wt) diet to rats for 5 weeks. The amount of vitamin E included in the ginseng-free and ginseng diets was either a low (low-E) or a normal (normal-E) level. The ginseng supplements significantly (p<0.05) altered the concentrations of plasma triglycerides in both the low-vitamin E group and normal-vitamin E group compared to the each ginseng-free group. The hepatic triglyceride and cholesterol content were not significantly (p>0.05) different between groups regardless of the vitamin E level in the diet. The hepatic HMG-CoA reductase activity was significantly (p<0.05) lowered by the ginseng supplement in both the low-vitamin E and the normal-vitamin E groups compared to the ginseng-free group. The HMG-CoA reductase activity was also significantly (p<0.05) lowered with in increase of the dietary vitamin E in the ginseng-free group. The excretion of fecal neutral sterol was significantly (p<0.05) lower in the normal-E ginseng group than th low-E ginseng-free group. Neither dietary ginseng nor vitamin E significantly changed the hepatic antioxidant enzymes activity. This data indicates that ginseng supplements lower the concentration of plasma triglyceride and hepatic HMG-CoA reductase activity regardless of eh dietary vitamin E level. This information may contribute to understanding the interactive effect of ginseng and vitamin E on cholesterol biosynthesis in high cholesterol-fed rats.

• Korean Journal of Rural Living Science
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• v.10 no.2
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• pp.60-70
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• 1999

Changes in the nutritional components of Toha-jeot, salt-fermented Toha shrimp (Caridina denticulata denticulata $D_EH_{AAN}$), which was salted with a low-salt group of 15% sodium chloride (L), a high-salt group of 23% sodium chloride (H), a 50% conventional soybean sauce group (S) during long fermentation were investigated. These three groups were refrigerated at ${4\pm}1^{\circ}C$ and then taken out for analysis at three month intervals during 9 month. Even in the process of a long fermentation, the moisture containment of Toha-jeot in group L and S is 76.0~73.6% and in group H it is 70.0%, which are similar in all three groups. In case of the salinity, there was no change in groups L, H but it was lowered in group S during the fermentation. In all groups there was no change of pH. The free amino acid contents in Toha-jeot, of which ornitine, glutamic acid, leucine, alanine, lysine and valine occupy the majority, in order of abundance, increased gradually up to six months of fermentation and decreased by nine months. But free amino acid contents of S group increased continuously during the fermentation process. Hypoxanthine was altered almost among other nucleotides. ATP was not detected, IMP and inosine had disappeared after the six months for mentation. ADP was not detected after the nine months fermentation. Monoene, polyene and n-3 fatty acids were increased and saturated fatty acids were decreased in L and H groups. However, no changes of fatty acid contents in S group during fermentation were showed. The fatty acid contents of three groups, of which $C_{18:1},\;C_{16:0},\;C_{16:1}$ and $C_{20:5}$ occupy the majority, Mineral content of Toha-jeot is mainly consisted of Na, Ca, K and Mg. In the Hunter values, the redness of L group was superior to that of other groups.

• Proceedings of the KWS Conference
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• 2010.05a
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• pp.18-18
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• 2010

최근에 건조되는 선박이나 구조물들은 점차 대형화 되어가고, 이에 사용되는 판재들은 점차 고강도 극후판재화 되어가고 있다. 극후판재의 용접성을 향상시키기 위해서는 대입열 용접이 주로 적용되고 있는 실정인데, 30 mmt 이상의 후판을 1 pass로 용접하기 위해서는 EGW(Electro-gas welding) 기법을 사용한다. 대입열 용접은 용접입열(heat input)이 매우 높아 용착금속과 열영향부의 냉각속도가 매우 느려 용접열영향부에서 특히 fusion line 근처의 열영향부는 결정립 조대화 및 취약한 미세조직을 형성함으로서 저온인성을 크게 저하시키고, 연화 현상(softening effect)을 발생시켜 강도가 저하되는 문제점이 주로 발생하였다. 하지만 이런 문제점을 해결하기 위해 대입열용접에 사용된는 강재의 미세조직을 제어하여 AlN, TiN, $TiO_2$ 등의 석출물을 이용한 용접열영향부의 저온인성을 향상시켰다. 이러한 문제점이 발생하는 대입열용접에서 저온인성 시험은 주로 fuison line + 1, 2mm에서 수행한다. 하지만 대입열 용접시 용착금속의 냉각속도도 매우 느리기 때문에 용착금속의 위치에 따라 저온 인성 특성이 다르게 나타날 수 있다. 본 연구에서는 EGW 용착금속의 위치에 따른 저온인성 특성을 평가하기 위해 EH-36N, 40mmt 판재를 사용하여 1pole EG 용접 하였다. 용착금속의 저온인성 특성을 평가하기위해 충격 시편의 노치 위치가 fusion line - 2mm와 용접부 중앙을 기준으로 4곳을 선정하여 충격시험을 수행하였다. 또한 용착금속의 경도 분포를 알아보기 위해 micro vickers hardness tester(mitutoyo UR-501)을 사용해 hardness mapping 시험을 하였다. 용착금속의 저온인성은 미세조직과, 산소량에 따라 변화 할 수 있기 때문에 용착금속 위치를 달리하여 미세조직과 산소량도 각각 분석하였다. 용착금속의 저온인성을 향상시킬 수 있는 침상형페라이트와 비금속개재물의 상관관계에 관해 검토 하였다.

• Journal of Oriental Medical Thermology
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• v.5 no.1
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• pp.78-86
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• 2006

Objectives: To examine any potential relationships between the types of alopecia and the facial heat distribution in patients with alopecia Methods: 183 patients with alopecia participated in this study to provide facial heat distribution measured by the Infrared Thermography Scanner (ITS, Nec San-ei Instruments Ltd, Japan). The thermography scan was used in a light-and heat-protected room after 20 minutes’of resting period. 1.5m of distance maintained between the patients and ITS. Results: Specificity in the type of facial heat distribution was found as follow. 1. Types of facial heat distribution can be classified as T-type and diffused patterns. 2. There was a significant difference in the pattern of facial heat distribution among different types of alopecia (p=0.002): facial heat distribution appeared T-type in Androgenic Alopecia, Alopecia Areata, and Telogen Effluvium (71.3%, 85.7%, 70.4%), whereas diffused pattern was dominant in Seborrheic Alopecia(55.6%). 3. There was a significant difference in the pattern of facialheat distribution between men and women (p<0.001): While the T-type and diffused type were equally appeared in men (50.6%: 49.4%), T-type was dominant in women (88.0% vs. 12.0%). Conclusions: We conclude that the pattern of facial heat distribution differs depends on the types of alopecia and gender. These differences may provide useful information for the diagnosis and clinical therapy for this population.