• Journal of Integrative Natural Science
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• v.4 no.4
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• pp.311-314
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• 2011

Application of self-assembled monolayers (SAMs) to the fabrication of organic thin film transistor has been recently reported very often since it can help to provide ohmic contact between films as well as to form simple and effective electrode pattern. Accordingly, quality of these ultra-thin films is becoming more imperative. In this study, in order to manufacture a high quality SAM pattern, a hydrophobic alkylsilane monolayer and a hydrophilic aminosilane monolayer were selectively coated on $SiO_2$ surface through the consecutive procedures of a micro-contact printing (${\mu}CP$) and dip-coating methods under extremely dry condition. On a SAM pattern cleaned with SC1 solution immediately after ${\mu}CP$, poly(3,4-ethylenedioxythiophene) (PEDOT) source and drain electrode array were very selectively and nicely vapour phase polymerized. On the other side, on a SC1-untreated SAM pattern, PEDOT array was very poorly polymerized. It strongly suggests that the SC1 cleaning process effectively removes unwanted contaminants on SAM pattern, thereby resulting in very selective growth of PEDOT electrode pattern.

• Journal of Soil and Groundwater Environment
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• v.21 no.3
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• pp.6-13
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• 2016

The effect of blast oxygen furnace (BOF) slag used as filling materials on the soil environment was studied using column tests that simulated the flow of the BOF slag leachate through the soil layer. The Cu, Mn, Zn, Ni, and F contents of the leachate affected soil were similar to that of the controls (i.e., soils that were not affected by the leachate). The As, Cd, and Pb contents were lower in the leachate affected soils than the controls. The changes in these contaminants contents can be attributed to the interactions between anions such as alkalinity generating anions (e.g., CO₃²⁻, HCO₃⁻, OH⁻) or calcium ions with heavy metals or F, which consequently affected the fate of heavy metals and F in the leachate affected soils. The germination and growth of Spinapis alba in the soils affected by the leachate and the controls were also similar. However, the proportion of alkalophilic bacteria in the soils affected by the leachate significantly increased, and this can be explained by the increased soil pH due to the alkaline leachate. Overall, this study shows that the alkalinity of the BOF slag leachate, rather than the presence of heavy metals and F in the leachate, needs to be considered when the BOF slag is to be reused as structural filling materials.

• Journal of the Korean Society of Groundwater Environment
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• v.1 no.2
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• pp.105-112
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• 1994

To investigate the migration behavior of contaminants in rocks. adsorption and diffusion experiments for Sr as a sorbing contaminant and for Cr-EDTA as a non-sorbing contaminant were carried out on granitic rocks. The Sr adsorption on separated minerals and crushed rocks tends to slightly increase with increasing pH. It also greatly decreases with the increase of ionic strength in NaCl solution. Among separated minerals, biotite and sericite have adsorbed much more amount of Sr than other rock-forming minerals, such as quartz, plagioclase, and potassic feldspar, because the specific surfaces and cation exchange capacities of phyllosilicates are generally much greater than those of the other rock-forming minerals. The intrinsic diffusion coefficients of Cr-EBTA for granitic rocks differ little from those of Sr. This indicates that they are independent of water-rock interactions. Experimental data show that the intrinsic diffusion coefficients are positively correlated with the porosities of the rocks. They are close to the theoretically predicted values, especially in pre-steady state diffusion region, with the increase of rock sample thickness.

• Journal of Environmental Impact Assessment
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• v.24 no.6
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• pp.549-560
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• 2015

The priorities of siting restriction was derived from quantification of environmental hazard according to industrial classification based on 'Chemical Ranking and Scoring System(CRS)' which is handling the discharge characteristics of 31 industrial classifications regulated from locating at 'Industrial Complex in Rural Area(ICRA)'. CRS that is utilizing the data of 'Pollutant Release and Transfer Registers(PRTR)' is applied to determine human health risk and ecological risk which are calculated by discharged amount and materials $LC_{50}$ according to water, soil and air media based on industrial classification. From this process, exposure assessment and toxicity assessment for integrating the adverse environmental impact and the mitigation effect of environmental risk according to the development of environmental technologies into establishing the rational landuse management method for the 31 industrial classifications regulated from locating at ICRA was analyzed. From the assessment result of the siting restriction removal at ICRA for 31 industrial classifications, based on 2012 year reference 6 industries that includes Manufacture of Guilt Coloration Surface Processing Steel Materials, Manufacture of Biological Product, Manufacture of Smelting Refining and Alloys of Copper, Dyeing and Finishing of Fibers and Yarns, Manufacture of Other Basic Iron and Steel n.e.c., Rolling Drawing and Extruding of Non-ferrous Metals n.e.c. are calculated as having relatively lower environmental hazards, thus it is judged that the siting restriction mitigation at ICRA is possible for the 6 industrial classifications that are not discharging the specific hazardous water contaminants during manufacturing process.

• Journal of the Korean Society of Groundwater Environment
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• v.3 no.1
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• pp.27-36
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• 1996

The Nanji landfill is one of the biggest uncontrolled landfill in terms of its size and scale in the world. Because the landfill was constructed on the very vulnerable alluvial deposit installing no pollution control systems such as bottom liner and leachate collection systems, it has caused a serious adverse effect to near-by groundwater and surface water systems. A through remedial investigation comprising plume detection and site-characterization was performed to design the remedial measure. As a part the investigation, comprehensive water quality study was conducted, using ten existing observation wells and one bundle type monitoring well, to determine the contaminant indicators for the plume delineation and to define the vertical and horizontal variation of specific contaminants via distances from the landfill. The results clearly shows that EC and temperature are a good pollution indicators and the vertical concentrations of specific contaminants measured in the fully screened wells are 20 to 90% more than those measured at the same depth in bundle type well which is located just 2 m apart. This paper presents a cost effective monitoring and sampling method to define the contaminant plume and obtain a basic data for leachate control measures.

• Journal of Life Science
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• v.8 no.4
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• pp.421-425
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• 1998

The antifungal activity of polygodial, which was isolated from Polygonum hydropiper used as a hot spice in Japan, was investigated through measuring its MICs and against food-contaminants including 4 strains of Saccharomyces cerevisiae, 3 strains of Zygosaccharomyces species, and 5 strains of Aspergillus species. All yeast-like fungi exhibited strong antifungal susceptivilities with MICs and MFCs below 3.13${\mu}g$/ml. Strains of Aspergillu species showed moderate with MIC of 25-50${\mu}g$/ml and MFC of 50-100${\mu}g$/ml. However these strains to sorbic acid, as already known, revealed very weak with MICs of 200-800${\mu}g$/ml and MFCs above 1600${\mu}g$/ml. In addition, effects of various pHs and temperatures on the antifungal activity of polygodial were tested against S. cerevisiae. At $4^{\circ}C$, the fungicidal activity of polygodial gradually increased with incubation time and reached the maximum(MFC of 3. 13${\mu}g$/ml) in 5 hours. At temperatures in the range of 30-$45^{\circ}C$, the activity of polygodial increased in proportion to temperature rise and in particular at $45^{\circ}C$ was possible with the concentration of 0.1${\mu}g$/ml. mOn the other hand, medium pH was also identified to affect the antifungal activity of polygodial. Namely, compared to neutral (pH7), acidic(pH 3) and basic(pH 9) medium synergized its activity (MIC and MFC) to 8- and 2- fold, respectively.

• Journal of Life Science
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• v.26 no.1
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• pp.75-82
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• 2016

Pseudomonas rhodesiae KK1 has been reported to degrade polycyclic aromatic hydrocarbons (PAHs), such as anthracene, naphthalene, and phenanthrene, which are considered major environmental contaminants. Interestingly, antioxidant genes, including superoxide dismutase, are known to be expressed at different levels in response to environmental contaminants. This study was performed to identify the superoxide dismutase gene in strain KK1, which may be indirectly involved with degradation of PAHs, as well as to investigate the expression pattern of the superoxide dismutase gene in cells grown on different PAHs. Two types of superoxide dismutase genes responsible for the antioxidant defense mechanism, Mn-superoxide dismutase (sodA) and Fe-superoxide dismutase (sodB), were identified in P. rhodesiae KK1. The sodA gene in strain KK1 shared 95% similarity, based on 141 amino acids, with the Mn-sod of P. fluorescens Pf-5. The sodB strain, based on 135 amino acids, shared 99% similarity with the Fe-sod of P. fluorescens Pf-5. Southern hybridization using the sod gene fragment as a probe showed that at least two copies of superoxide dismutase genes exist in strain KK1. RT-PCR analysis revealed that the sodA and sodB genes were more strongly expressed in response to naphthalene and phenanthrene than to anthracene. Interestingly, sodA and sodB activities were revealed to be maintained in cells grown on all of the tested substrates, including glucose.

• Korean Journal of Heritage: History & Science
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• v.44 no.3
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• pp.92-111
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• 2011

This study focus on the restoration stone selection of break-out part based on material characteristics analysis and the conservational safety diagnosis using various nondestructive techniques for Jungdong and Banjukdong Stone Auariums. As a result, the original rocks of the stone aquariums body are porphyritic granodiorite with magnetite-series having igneous lineation, microcline phenocryst, veinlet and basic xenolith. As a result of the provenance presumption of the host rock, a rock around Gamgokri area in Nonsan City was identified the genetically same rock. Therefore, the rock is appropriate for restoration materials of the break-out part. The deterioration assessment showed that the stone aquariums were highly serious scaling, scale off and blackening. Particularly, the front face of Banjukdong stone aquarium needs reinforcement of structural crack (760mm) caused from igneous lineation of biotite. Blackening contaminants on the stone aquariums surface occurred by combining iron oxide, manganese oxide and clay mineral. Also, major factors of efflorescence contaminants were identified as calcite (Jungdong stone aquariums) and gypsum (Banjukdong stone aquariums). The physical characteristics of stone aquariums appeared that the original and new stone is third (moderately weathered) and second grade (slightly weathered), respectively. This study sets up an integrated conservation system from material analysis to restoration stone selection and conservational safety diagnosis of Jungdong and Banjukdong stone aquariums.

• Geophysics and Geophysical Exploration
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• v.22 no.3
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• pp.132-148
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• 2019

Recently, safety and environmental concerns have become major social issues. Especially, a special underground-safety law has been made and enacted to prevent ground subsidence around construction sites. For environmental problems, several researches have started or will start on characterization of contaminated sites, in-situ environmental remediation in subsurface, and monitoring of remediation results. As a part of the researches, geophysical surveys, which have been mainly applied to explore mineral resources, geological features or ground, are used to characterize not only contaminated areas but also fluid flow paths in subsurface environments. As a basic study for the application of geophysical surveys to detect contamination in subsurface, this paper analyzes previous researches to understand changes in geophysical properties of contaminated zones by various contaminants such as leachate, heavy metals, and non-adequate phase liquid (NAPL). Furthermore, this paper briefly introduces how geophysical surveys like direct-current electrical resistivity, induced polarization and ground penetration radar surveys can be applied to detect each contamination, before analyzing case studies of the applications in contaminated areas by NAPL, leachate, heavy metal or nitrogen oxides.

• Korean Journal of Heritage: History & Science
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• v.56 no.3
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• pp.138-156
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• 2023

Some of the metal cultural heritage that make up a considerable proportion of Korea's cultural heritage have been installed and displayed outdoors due to their own functions, roles, and scale. Therefore, more diverse and complex damages can occur outdoors than they are in a stable environment. Therefore, it is necessary to combine accurate diagnosis and systematic survey methods in order to utilize basic data obtained from research results as data for the long-term and continuous conservation management as well as to do the research to diagnose the conservation status of outdoor cultural heritage. The clepsydra(hereinafter referred to as Jagyeongnu) of Changgyeonggung Palace, the National Treasure has been installed and displayed outdoors since it was manufactured. Though regular conservation and maintenance of the Jagyeongnu have been carried out, damage still occurred. Therefore, the scientific research on Jagyeongnu to diagnose the state of conservation was conducted prior to the full-scale conservation treatment. First, the state of conservation was investigated with an examination of basic data, macroscopic inspections and past records of repair history according to the purpose of the research. More detailed examinations were also conducted through the 3D scan, surface pattern investigation, and color difference analysis, and the analysis on materials and contaminants were conducted through P-XRF, FT-IR, and Py-GC/MS. The scientific research reveals that squalane and silicone oil have been applied in the past for conservation treatment and directly exposed to outdoor environmental factors, which caused damage to Jagyeongnu and contaminants such as dust adhered thickly to its surface, accelerating severe damage. A greater incidence of damage was found around the part with relatively high exposure effect, which corresponded with the tendency identified by grouping color difference data. As a result of integrating various research methodologies to diagnose the state of conservation and secure basic data, the causes and types of damage were identified. Furthermore, the process of obtaining digital data to be utilized in various ways, and the color difference analysis presenting visible damage as scientific data and identifying the tendency of damage patterns were confirmed to have been effective.