• 한국지하수토양환경학회지:지하수토양환경
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• 제21권6호
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• pp.14-21
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• 2016

This study evaluated the applicability of stabilization of arsenic (As)-contaminated soil with iron (Fe) oxides at the former Janghang smelter site. Three Fe oxides (magnetite, goethite, and hematite) were tested as stabilizing agents to one soil sample collected from the study site. Amendment of 5% of magnetite, goethite, or hematite for one week showed the 64, 58, and 36% of reduction of the SBRC (Solubility/Bioavailability Research Consortium)-extractable (bioaccessible) As, respectively. Duration of stabilization more than one week did not show an additional reduction in SBRC-extractable As. Amendment of 5% of magnetite, which showed the highest As stabilization efficiency, was applied to 24 soil samples collected from the same site for one week, and 72% of reduction in the bioaccessible As was observed. The potential carcinogenic human health risk at the study site caused by As was $1.7{\times}10^{-5}$, which could be reduced to $8.1{\times}10^{-6}$ by the amendment of 5% magnetite for one week.

• 분석과학
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• 제26권6호
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• pp.387-394
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• 2013

인골에서 추출된 콜라겐의 탄소와 질소 안정동위원소 정보는 당시 사람들의 식생활과 영양 상태, 생계 경제를 복원하는데 구체적인 가능성을 제시한다. 지금까지 우리나라의 신석기시대 유적에서는 인골이 많이 발견되지 않아 직접적인 식생활 양상 추적이 어려웠는데, 부산 가덕도 장항유적에서 출토된 인골 48개체의 확인은 매우 주목할 만한 성과이다. 본 연구에서는 인골에서 추출된 콜라겐의 탄소와 질소 안정동위원소 분석을 수행하였으며, 평균값은 각각 다음과 같다(${\delta}^{13}$C=$-14.5{\pm}1.3$‰, ${\delta}^{15}$N=$-17.4{\pm}1.7$‰, n=10). 뼈의 조직 분석 결과 보존 상태는 매우 안좋은 HI (조직학 지수) 0을 나타냈으나, 뼈 콜라겐의 경우 질 평가지수에 합격한 값만을 사용하여 생존 시 식생활을 반영한다는 것을 알 수 있었다. 당시의 고고학적인 정황을 고려할 때 장항 유적 피장자들은 해양성 식료를 주로 섭취하였고, 육상 동물 및 야생 식물의 섭취 가능성 역시 배제할 수 없는데, 본 연구에서는 식료 섭취의 직접적인 증거가 되는 인골의 안정동위원소 분석을 통해 이러한 가정을 입증하였다. 이 외에도 펴묻기와 굽혀묻기 등 장법이나 토기 등 부장품에 따른 안정동위원소값에서는 유의미한 차이를 확인할 수 없었다. 신석기시대 최대 집단 묘역인 부산 가덕도 장항 유적 출토 인골 콜라겐의 탄소와 질소 안정동위원소 분석은 우리나라 신석기 시대 생활상을 복원하는 데 매우 핵심적인 증거가 될 것이라 기대된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권3호
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• pp.21-31
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• 2012

This paper presents the short-term and long-term measures to determine the fugitive dust concentration in a contaminated site, which is a crucial step for the determination of particulate emission factor (PEF) for risk assessment. As a long-term measure, USEPA method employing Q/C value (inverse of the ratio of the geometric mean air concentration to the emission flux at center of a 0.5-acre square source) seems to be suitable as it reflects regional-specific meteorological conditions. However, it requires nation-wide database collection and interpretation. Use of ASTM method is an alternative as a short-term measure. The method is readily field-applicable as PEF calculation equation is simple and input parameters can be easily derived at the site of interest as well without the nation-wide efforts. Using ASTM method, PEF at the Former Janghang Smelter Site was determined. According to various mode of aggregate size distribution and fractions of vegetative cover, which are the most important factors in PEF calculation, PEF values at the Former Janghang Smelter Site varied greatly. When the mode of aggregate size distribution was set at 0.25 mm, PEF values at the Former Janghang Smelter Site was 5~20 times higher than the default PEF value (i.e., 35 ${\mu}g/m^3$) shown in the current Korean Soil Contamination Risk Assessment Guidance. On contrast, when the mode was set at 2 mm, PEF values at the Former Janghang Smelter Site was 160~640 times lower than the default PEF value in the Korean Guidance.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 추계학술대회 논문집
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• pp.250-257
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• 2000

The speed-up of conventional trains is considered as one of the efficient methods to relieve traffic jam and to increase the capacity of transportation. In this study, we measured and analyzed the ride comfort of a push-pull Saemaeul Train with speed-up of 5km/h in curves and 10km/h on straight tracks as compared with present operation speed of the push-pull Saemaeul Trains. Four main lines-Honam, Kyungboo, Janghang, Kyungjeon- were chosen as representative lines for speed-up feasibility study. The increase of mean ride comfort index in case of speed-up is 0.5-2㏈. The mean ride comfort index of vertical direction in case of speed-up is 107-110㏈ for Honam line, 104-112㏈ for Kyungboo line, 108-112㏈ for Janghang line and 105-108㏈ for Kyungjeon line, which are rather high as compared with German trains of similar grade with maximum vehicle speed of 160km/h.

• 환경생물
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• 제38권1호
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• pp.61-70
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• 2020

A eukaryotic microalga was isolated from seawater in Janghang Harbor, Korea and its morphological, molecular, and physiological characteristics were investigated. Due to its simple morphology, no distinctive characters were found by morphological observation, such as light microscope or scanning/transmission electron microscopy (S/TEM). However, molecular phylogenetic evidence inferred from the concatenated small subunit (SSU) 18S rRNA and internal transcribed spacer (ITS) sequence data indicated that the isolate belonged to the newly described Micractinium singularis. Furthermore, it was clustered with Antarctic Micractinium strains and it also showed a psychrotolerant property, surviving at temperatures as low as 5℃. However, its optimal growth temperatures range from 15℃ to 25℃, indicating that this microalga is a mesophile. Additionally, gas chromatography-mass spectrometry (GC/MS) analysis showed that the isolate was rich in nutritionally important omega-3 polyunsaturated fatty acid, and high-performance liquid chromatography analysis (HPLC) revealed that the high-value antioxidant lutein was biosynthesized as an accessory pigment by this microalga, with glucose as the major monosaccharide. Therefore, in this study, a Korean marine M. singularis species was discovered, characterized, and described. It was subsequently added to the national culture collections.

• 한국지하수토양환경학회지:지하수토양환경
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• 제22권6호
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• pp.1-11
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• 2017

This study was conducted to investigate the performance of four commercial chemical agents in stabilizing arsenic (As) in soil at the forest area near the former Janghang smelter site. After amending the stabilizing agents (A, B, C, and D) into As-contaminated soil samples, synthetic precipitation leaching procedure (SPLP) and solubility bioavailability research consortium (SBRC)-extractable As concentrations significantly decreased except for agent D, which is mainly composed of fly ash and calcium carbonate. Increase of SPLP and SBRC-extractable As concentrations in four soil samples (S1, S2, S3, and J2) was attributed to desorption of As adsorbed on iron oxides due to high pH generated by agent D. It is therefore necessary to consider application conditions according to soil characteristics such as pH and buffering capacity. Results of sequential extraction showed that readily extractable fractions of As in soil (i.e., sum of $SO_4-$ and $PO_4-extractable$ As in soil) were converted into non-readily extractable fractions by amending agents A, B, and C. Such changes in the As distribution in soil resulted in the decrease of SPLP and SBRC-extractable As concentration. A series of follow-up monitoring and management plan has been suggested to assess the longevity of the stabilization treatments in the site.

• 한국광물학회지
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• 제10권2호
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• pp.139-147
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• 1997

The Janghang smelter is the first lead, zinc and copper smelting facility in Korea which was operated for a half century from 1936 to 1989. The clay minerals and their heavy metal association in the soil profile around the smelter have been studied using XRD, EPMA, SEM-EDS, TEM, EPR and sequential extraction techniques. The soils in A horizon are highly acidic showing pH 4.45. The pH is going up with increasing depth. They have residual water contents of 1.18-1.51 wt%, loss on ignition of 6.32-7.79 wt%, and carbon contents of 0.08-0.88 wt%. Soils consist of quartz, feldspar, muscovite, kaolinite, vermiculite, biotite, chlorite, goethite and hematite in the decreasing abundance. The contents of clay minerals, especially vermiculite and chlorite, decrease with increasing depth. Sequential extraction experiments for the profile samples show that heavy metals (Zn, Cu, Pb, Cd) are highly concentrated in the A horizon of the soil profile as water-extractable (mostly amorphous), MgCl2-extractable (exchangeable in clay minerals), and organic phases. The heavy metal contents decrease with increasing depth. It suggests that the heavy metals are mainly associate with clay minerlas in an exchangeable state. It is also noted that heavy metals are highly concentrated in the manganese and iron oxide phases.

• 박물관보존과학
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• 제14권
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• pp.115-124
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• 2013

국립경주박물관 옥외전시장의 장항리 석조불입상은 외부환경에 의한 접합물질의 풍화와 표면 오염물의 고착, 암석의 편하중에 의한 균열 등의 문제점으로 인해 소장품의 안전한 관리를 위한 해체 및 복원작업을 진행하였다. 3D 정밀실측을 통한 도면화 및 기초자료 조사, 풍화된 부분의 시멘트몰타르 및 수지를 제거하였다. 복원부분은 동종의 암석을 사용하여 신석을 제작하여 접합·복원하였다. 또한 미생물의 피해를 방지하기 위하여 훈증처리를 실시하였으며 지속적인 관찰을 진행중에 있다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권1호
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• pp.40-48
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• 2016

A siderophore-producing bacterium (i.e., Pseudomonas aeruginosa) capable of chelating Fe³⁺ from its mineral form (i.e., iron oxides) was used to enhance As uptake by plants. Since As in soil is mainly associated with iron oxides, siderophore can play an important role in As mobilization through the dissolution of As-bearing iron oxides. A series of pot experiment using Pteris cretica showed that As removal by P. cretica with siderophore-producing bacteria addition increased more than three times compared to that without bacteria addition. Competition between indigenous bacteria and introduced bacteria (i.e., P. aeruginosa) was also observed, but such competition seemed not to be significant. This study suggests that enhanced-phytoremediation by siderophore-producing bacteria addition could be a visible option for longterm As removal in the forest area at the former Janghang smelter site.

• 생태와환경
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• 제43권2호
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• pp.298-306
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• 2010

한강하구 장항습지의 선버들군락의 현존량과 1차생산성을 상대생장법(allometry)과 기저 단면의 나이테를 이용하여 추정하였으며, 버드나무림 하부에 서식하는 말똥게 개체군의 2차생산성을 추정하였고 두 개체군 간의 관계성을 해석하였다. 선버들군락의 지상부 1차생산성은 4,777 g DW $m^{-2}yr^{-1}$으로서 국내에서 최고의 생산성을 나타내었다. 장항습지에서 선버들에 의해 저토로 공급되는 내생유기물량은 359 g C $m^{-2}yr^{-1}$이며 외생유기물량은 347 g C $m^{-2}yr^{-1}$로 나타났다. 말똥게의 2차생산성은 100.2 g FW $m^{-2}yr^{-1}$로 선버들 군락의 지상부 1차생산성의 2.1%로 나타났다. 선버들군락 내 말똥게의 생물량은 140 g FW $m^{-2}$이며 이들의 연간 먹이소비량은 약 2,140 g FW $yr^{-1}$이고, 말똥게의 연간 섭식량은 약 208 g C $m^{-2}yr^{-1}$로 추정하였다. 본 연구로부터 장항습지의 주요 생물구성원인 선버들군락과 말똥게의 높은 생산성을 확인하였다.