• Economic and Environmental Geology
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• v.55 no.1
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• pp.97-109
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• 2022

This study focused on the physicochemical effects of bottom ash dissolved precipitation on the soil and groundwater environment. The iced column and percolation experiments showed that most of the bottom ash particles were drained as the ash-dissolved solution, while the charcoal powder was filtered through the soil. Ion species of Al, As, Cu, Cd, Cr, Pb, Fe, Mn, Ca, K, Si, F, NO₃, SO₄ were analyzed from the eluates collected during the 24 h column test. In the charcoal powder eluates, a high concentration of K was detected at the beginning of the reaction, but it decreased with time. The concentrations of Al and Ca were observed to increase with time, although they existed in trace amount. In the bottom ash eluates, the concentrations of Ca and SO₄ decreased by 30 mg·L^-1 and 67 mg·L^-1, respectively, over 24 h. It is regarded that the infiltration patterns of the bottom ash and biochar in the unsaturated zone were different owing to their particle sizes and solvent properties. It is expected that a significant amount of the bottom ash will mix with the precipitation and percolate below the water table, especially in the case of thin and highly permeable unsaturated zone. The biochar was filtered through the unsaturated zone. The biochar did not dissolve in the groundwater, although it reached the saturation zone. For these reasons, it is considered that the direct contamination by the bottom ash and biochar are unlikely to occur.

• Applied Biological Chemistry
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• v.42 no.2
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• pp.134-139
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• 1999

The characteristics of anthocyanin pigments extracted from cherry(Prunus serrulata L. var. spontanea Max. Wils.) were investigated at the various conditions, such as light, temperature, organic acid, metal ion and pH. The pigments were fairly stable under the sunlight during the 20 days storage period at room temperature. The pigments covered with the Al-foil, as well as red, blue, green and yellow films, were very stable at pH 2.5. The high thermal stability (over the 64% at $115^{\circ}C$, 30 min) of the pigments in the dark at pH 2.5 was also found. In the presence of organic acid, the hyperchromic effect of red color was greatly increased in the dark at $25^{\circ}C$. Addition of metal ion, such as $Na^+,\;K^+,\;Mg^{2+},\;Ca^{2+}\;and\;Mn^{2+}$, was contributed on the stability in color at pH 2.5 throughout 20 days storage period in the dark at $25^{\circ}C$. However, $Cu^{2+}\;and\;Fe^{3+}$ caused the rapidly degradation of pigments, and $Al^{3+}$ converted red color to blueish violet. The hyperchromic effect of the red color increased, as pH decreased. Therefore, these results indicated that cherry anthocyanin pigments might be used as the potential sources of natural red colorant for foods.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.363-364
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• 2009

For the application of superconductor technology, we need critical properties of superconductors such as a critical current ($I_c$). $I_c$ is varied as processing method by action of flux pinning center. Our research activities are reported on the establishment of standard measurement method for critical current in coated conductor. And then, we researched pre-studies for standardization of critical current evaluation method using IEC/TC 90 standard.

• Food Science and Preservation
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• v.4 no.3
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• pp.287-293
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• 1997

This study was investigated to viscosity, color, chemical properties, and lipid and fatty acid composition for examination of physical and chemical characteristics of sesame oils. Yield of sesame oil was higher in Ansan sesame than that of Chinese and Dambaek sesame. Viscosity of sesame oils was higher than that of shame oils from Dambaek and Chinese sesame, but turbidity and sedimentation rate were higher in Dambaek's sesame oil than those of Ansan's and Chinese sesame oils. In the acid value, saponification value and iodine value of sesame oils, and chemical characteristics of Dambaek's sesame oil were better than those of the others. The neutral, glycolipid and phosholipid contents of sesame oils were 91.1∼92.1, 2.5∼3.5 and 5.5∼6.4%, respectively. The major fatty acids of sesame oils were oleic, linoleic palmitic and stearic acid. The content of oleic acid was higher in Dambaek's and Ansan's sesame oil than that of Chinese sesame oil, and the content of linoleic acid was higher in Chinese sesame oil than the others. The fatty acid composition of neutral lipid, glycolipid and phospholipid were similar to those of total lipid. The ratio of unsaturated fatty acid and saturated fatty acid was higher in Korean sesame oils than those in Chinese sesame oil. The mineral(Mg, Cu, Fe, In, Al, Mn) content of Korean sesame oils was higher than that of Chinese sesame oil. and heavy metals(Cu, Ag, Pb, Cd, As) were not detected.

• Korean Journal of Human Ecology
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• v.11 no.4
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• pp.391-400
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• 2002

This study was intended to research the dyeing with natural walnut hull extracts over cotton, flax, rayon, wool, nylon and silk. We studied the dyeing conditions and mordant effect, and observed dyeability. The result are as follows: 1. In the dyeability with natural walnut hull extracts, protein and polyamide fiber has more dye uptake rather than cellulose fiber. 2. The optimum condition in the dyeing with natural walnut hull extracts was at $90^{\circ}C$, 12%(o.w.b) concentration in 90 mins. 3. In the case of the dyeability by repeated dyeing number, the dyeability of good dyeability fiber is improved in the first or second dyeing, but that of bad dyebality fiber is improved when it is dyed more repeatedly. 4. In the dyeablity treated with mordants, Al, Sn, and Mg don't have any differences, but Cu and Fe have some difference. The color of Fe mordant is green and the color of Cu mordant is blue. 5. In the case of the color fastness with mordant treatment, nylon is better than silk and wool in color fastness to washing but silk is better than nylon and wool in color fastness to light.

• Journal of Environmental Science International
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• v.10 no.3
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• pp.209-216
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• 2001

Dustfall particles were collected by the modified American dust jar (wide inlet bottle type) at 6 sampling sites in Pusan area from March, 1999 to February, 2000. Thirteen chemical species (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Si, and Zn) were analyzed by AAS and ICP. The purposes of this study were to estimate qualitatively various bulk deposition flux of dustfall and insoluble components by applying regional and seasonal distribution. Dustfall amount of regional variations were found in order of coastal zone, industrial zone, commercial zone, agricultural zone and residential zone, and seasonal total dustfall had higher concentrations during spring for 6.741 ton/${km}^2$/season, lower concentrations during summer for 1.989 ton/${km}^2$/season, and annual total concentration was 17.742 ton/${km}^2$/year. The regional distributions of enrichment factor show well-defined anthropogenic metals (Cd, Cu, Pb, and Zn) at industrial and agricultural zone, and contribution rate of soil particles were found in order of summer, fall, winter and spring. Factor loading effects of chemical composition of dustfall were found in order of road traffic emission source and combustion processed source, industrial activity source, soil source and marine source.

• Advances in environmental research
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• v.5 no.2
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• pp.79-94
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• 2016

In order to evaluate the contamination and health risk, levels of six hazardous elements i.e., Cr, Ni, Cu, As, Cd and Pb in soils of 12 different land-uses were measured. The average concentration of Cu, Cr, Ni, Pb, As and Cd in soils were 267, 239, 206, 195, 58 and 16 mg/kg, respectively. Levels of each metal exceeded the environmental action level for soils, which could pose significant risk to human. The metal concentrations were subsequently used to establish hazard indices (for adults and children) where the 5th and 95th percentile values were used to derive the hazard index through different exposure pathways (ingestion, dermal contact and inhalation). Considering the total exposure through each of the three pathways, the hazard index elucidates that there was a potency of non-cancer risk at most of the sites for both the adults and children. The findings of this study suggested that different land-use soils were severely contaminated with hazardous elements and attention is needed on the potential health risks to the exposed inhabitants.

• Korean Journal of Environmental Biology
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• v.23 no.3 s.59
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• pp.315-321
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• 2005

The population of river otter (Lutra lutra) has been declined most of the world due to hunting, habitat destruction and indirect or direct influences of eutrophication, acidification and toxic chemicals. This study is conducted to identify the population decline of river otter in Korea with relation to environmental pollution caused by accumulation of heavy and flared metals. The field survey was conducted during Jan~Dec, 2004 at a monthly basis by collecting spraints. A total of 228 spraints were collected and analysis was done by ICP-AES. The concentrations of fourteen metals (Cr, Zn, Cd, Pb, Ni, Fe, Co, Mn, Mg, Cu, Al, Ba Hg, As) have been determined. Annual concentrations of Cd $(1.38{\mu}g\;g^{-1}),\;Zn\;(599.06\;{\mu}g\;g^{-1}),\;Pb\;(5.54\;{\mu}g\;g^{-1})$ at Gucheon were higher than those of Yeonchocheon. Concentrations of $Cr\;(5.01{\mu}g\;g^{-1}),\;Ni\;(1.91{\mu}g\;g^{-1}),\;Co\;(0.25{\mu}g\;g^{-1})$ were higher at Yeonchocheon. Most metals in winter were significantly increased (P<0.05) as season progressed from spring to winter. $Pb\;(15.58{\mu}g\;g^{-1}),\;Cu\;(15.15{\mu}g\;g^{-1}),\;a;Guchoen\;and\;Cr\;(5.77{\mu}g\;g^{-1})$ at Yeonchocheon were high in the downstream of winter.

• Journal of Environmental Science International
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• v.11 no.7
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• pp.651-662
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• 2002

Weather elements were observed by the AWS (Automatic Weather System) and dustfall particles were collected by the modified American dust jar (wide inlet bottle type) at 4 sampling sites in Busan area from March. 1999 to February, 2000. Thirteen chemical species (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Si, and Zn) were analyzed by AAS and ICP. The purposes of this study were to estimate qualitatively various bulk deposition flux of dustfall and insoluble components by applying regional and seasonal wind intensity. Frequency of wind speed were found in order of low(1-3m/s), very low(<1m/s), medium(3-8m/s) and high(>8m/s), and annual mean had higher range at low(1-3m/s) for 56.3%. Strong negative linear correlation were observed between dustfall and wind direction (northeastern and eastern), but strong positive linear correlation were observed between dustfall and wind direction (western and northwestern) at industrial, commercial and coastal zone(p<0.05). While a negative correlation were observed between wind speed frequency of very low(<1 m/s) and dustfall, and positive correlation were observed between wind speed frequency of low(1-3m/s) and dustfall in coastal zone(p<0.05). The correlation coefficient was observed 0.556 between wind speed frequency of low(1-3m/s) and Ni by commercial zone(p<0.05). The correlation coeffcient show well-defined insoluble trace metals (Al, Ca, Cr, Cu, Fe, Pb, and Zn) and wind speed frequency of low(1-3m/s) at coastal zone, which was found significant difference(p<0.01).

• Economic and Environmental Geology
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• v.40 no.6
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• pp.727-738
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• 2007

The present study investigation the geochemical characteristics of the stream sediments in the Unbong area was conducted to enable a understanding the natural background and a prediction the prospects of geochemical disaster as a result of that bed rocks(mylonitic granites, Kim et al., 1992). We systematically collected seventy three stream sediments samples by wet sieving along the primary channels. Major, trace and rare earth element(REE) concentrations, combined with mineralogical characteristics, were determined by XRD, XRF, ICP-AES and NAA analysis methods. Major element concentrations for the stream sediments in the Unbong area were $SiO_2\;36.94{\sim}65.39wt.%,\;Al_2O_3\;10.15{\sim}21.77wt.%,\;Fe_2O_3\;3.17{\sim}10.90wt.%,\;CaO\;0.55{\sim}5.27wt.%,\;MgO\;0.52{\sim}4.94wt.%,\;K_2O\;1.38{\sim}4.54wt.%,\;Na_2O\;0.49{\sim}3.36wt.%,\;TiO_2\;0.39{\sim}1.27wt.%,\;MnO\;0.04{\sim}0.22wt.%,\;P_2O_5\;0.08{\sim}0.54wt.%$. Trace and REE concentrations for the stream sediments were $Cu\;4.8{\sim}134ppm,\;Pb\;24.2{\sim}82.5ppm,\;Sr\;95.9{\sim}739ppm,\;V\;19.9{\sim}124ppm,\;Zr\;52.9{\sim}145ppm,\;Li\;25.2{\sim}3.3ppm,\;Co\;3.87{\sim}50.0ppm,\;Cr\;17.4{\sim}234ppm,\;Hf\;3.93{\sim}25.2ppm,\;Sc\;4.60{\sim}20.6ppm,\;Th\;3.82{\sim}36.9ppm,\;Ce\;45.7{\sim}243ppm,\;Eu\;0.89{\sim}2.69ppm,\;Yb\;1.42{\sim}5.18ppm$. According to the comparison of average major element concentrations, CaO, $Na_2O\;and\;K_2O$ contents are higher in stream sediments than in bed rocks(mylonitic granites, Kim et al., 1992) $Al_2O_3\;and\;SiO_2$ contents show good correlation both stream sediments and bed rocks(mylonitic granites, Kim et al., 1992). Yb and Eu in the stream sediments show a positive correlation with $SiO_2$. In contrast, the stream sediments display a negative correlation.