• 한국지하수토양환경학회지:지하수토양환경
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• 제22권6호
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• pp.48-56
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• 2017

Although various methods have been investigated for treatment of crude oil contaminated soil, more researches are still required to preserve soil environment. This study investigated the potential utility of subcritical water in remediation of crude oil contaminated soil under various experimental conditions including temperature ($150-300^{\circ}C$), flow rate (1.0-2.0 mL/min) and extraction time (60-120 min). The removal rate of crude oil gradually increased with increasing temperature and time. After treatment at $200^{\circ}C$ and $300^{\circ}C$ for 60 min, the remaining concentration of crude oil met the Kuwait standard clean-up level (10,000 mg/kg) and the Korean standard level (2,000 mg/kg), respectively. The removal efficiency of crude oil increased from 77.8% to 88.4% with increasing extraction time from 60 to 120 min at $250^{\circ}C$. A decreasing rate of oil removal was observed as flow rate increased, possibly due to channeling flow occurred within the soil body at higher flow rate condition. Overall, the results revealed that subcritical water extraction process could be feasible for remediation of crude oil contaminated soil, and the relative effect of parameters on the oil removal was in the order of temperature > time > flow rate.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1069-1080
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• 2008

The mechanical characteristic of Lightweight Foamed Soil(LWFS) are investigated in this research. LWFS is composed of the in-suit soil, cement and foam to reduce the unit-weight and increase compressive strength. The unconfined compressive tests are carried out on the prepared specimens of LWFS with various soil types to investigate the relationship between compressive strength of LWFS and physical properties of soil. The result indicate that coefficient of gradation($C_g$) and liquid limit(LL) are more important factor affecting compressive strength than other physical properties of soil and coefficient of gradation($C_g$) and liquid limit(LL) can standard to determine the optical soil among the in-situ soils for LWFS.

• 한국환경과학회지
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• 제17권9호
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• pp.1015-1021
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• 2008

This study was performed to examine the accumulated concentrations (conc.) of cadmium (Cd) in the organs of Arabidopsis thaliana grown in the soil with different conc. of Cd. The official standard conc. of Cd of pollutant exhaust notified by the Korean ministry of environment (0.1 mg/L) and ten times higher (1 mg/L) and fifty times higher (5 mg/L) conc. and no Cd in the soil as control were used for this investigation. The results showed that accumulated conc. of Cd in the stems of plant grown in the soil with different conc. (0.1, 1 and 5 mg/L) were increased 9%, 24% and 286% respectively, compared with normal plant stem. The accumulated conc. of Cd in the leafs of plant gown in the soil with official standard conc. and conc. ten times higher and conc. fifty times higher were increased 3%, 22% and 453%, respectively, compared with normal plant leaf. The accumulated conc. of Cd in the root of plant grown in the soil with 0.1 and 1 mg/L conc. of Cd were increased 6%, 19%, respectively, compared with normal plant root. However, it was observed about 84% of increased accumulation of the Cd in the root of plant, when highest (5 mg/L) conc. was used. The accumulated conc. of Cd in the different organs of Arabidopsis thaliana were increased according to increase of Cd conc. in the soil. When official standard conc. and ten times higher conc. of Cd were used, the accumulated conc. of Cd increased average 6%, 21%, respectively, compared with normal plant organ, and the accumulated conc. of Cd between leaf, stem and root were not significant. However, the accumulated conc. of Cd in the plant organs gown in the conc. fifty times higher were increased about 285%, compared with normal plant. In addition, the accumulated conc. of Cd in different organs of Arabidopsis thaliana exhibited wide differences between organs, that is, stem was increased 118% than root, leaf was increased 256%, 64% than root and stem, respectively. These results show that accumulated conc. of Cd in Arabidopsis thaliana with highest (5 mg/L) conc. of Cd in soil, were much higher in the leaf than the stem or root in proportion to the conc. of Cd contaminated within the soil.

• 한국지하수토양환경학회지:지하수토양환경
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• 제16권1호
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• pp.71-81
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• 2011

Cause of contamination in the study area nearby Jang Hang Refinery is dust scattering in refinery stack, and soil washing treatment is one of the proper technologies for soil remediation in this area. Site conditions frequently limit the selection of a treatment process. A treatment technology may be eliminated based on the soil classification or physicochemical characteristics of soil. This study was assessed the soil washing efficiency by conducting of soil characteristic analysis in the vicinity of Jang Hang Refinery Stack within a 2 km radius. Also, it was decided about remedial range with comparative analysis of As in soil by Korean Standard Test Method before/after revision, whereupon As concentration in soil showed a increasing tendency after revision. As a result, the soil washing using the size separation of soil was determined through identifying of As species in the soil. In this site, only particle size distribution and water content of soil can provide the initial means of screening for the potential use of soil washing.

• 한국의류학회지
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• 제45권5호
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• pp.840-851
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• 2021

In this study, we used a chemiluminescence reaction to investigate the removal effect of pet soil, such as dog blood, urine and feces. The soiled fabrics were washed with a standard laundry course of 30℃ and a washing time of 30 min and a pet care laundry course of 40-60℃ and a washing time of 100 min. The detergency was evaluated by the surface reflectance and chemiluminescence reaction (bloodstain detection by luminol test and urine-stain and feces-stain detection by UV blacklight test) before and after washing. The surface reflectance results did not show any difference in detergency for both courses, whereas the chemiluminescence reaction did. The detergency of the pet care course compared to the standard course was 101% according to the surface reflectance and 120% according to the chemiluminescence reaction. Therefore, residual stains not detected by surface reflectance can be evaluated through chemiluminescence reaction, and it was confirmed that pet stains can be managed more hygienically by washing for a long time at a high temperature.

• 한국환경복원기술학회지
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• 제23권6호
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• pp.57-73
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• 2020

A study was conducted to present the criteria for evaluating the revegetation method of the slope of the expressway. The results of comparative analysis between 2019-2020 field survey and existing research data (2015-2016) are as follows. Soil is a very important factor at the beginning of revegetation work. However, after the plant has settled, the importance of the soil composition diminishes. Among the plants used, the number of plants sown at the beginning gradually decreases. And it changes as it competes with invading plants. Among the plants used for sowing, it was found to affect the vegetation composition in the order of exotic grass > native herb and wildflower > native tree. Plant coverage is continuously evaluated as an important factor regardless of the time. The vegetation structure on the slope will change continuously over time. New items need to be evaluated in situations where a lot of time has elapsed since the application of revegetation work. It is desirable to use the current evaluation standard only to perform the evaluation within 1 to 2 years. In the long run, it is necessary to establish a new evaluation standard that adjusts the weights of each item.

• 한국토양비료학회지
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• 제42권5호
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• pp.399-407
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• 2009

레이저 유도붕괴 분광법(LIBS)은 물질상태(고체, 액체, 기체)에 상관없이 신체 접촉시 오염 우려 및 미량 시료도 전처리 없이 동시에 많은 종류의 원소 분석으로 분석과정이 단순하고 신속하게 분석이 가능하며, 소형화된 레이저의 개발로 시료의 직접적인 채취가 어려운 조건의 현장분석에도 적합하다. 농산물 안정성 평가나 친환경 농업 및 정밀농업을 위한 조사 등에 활용될 수 있는 비파괴 실시간 정량분석기술로서 LIBS 분석법의 토양분석 가능성을 평가하고자 표준광물, 미국의 표준기술연구소의 표준토양, 미국 테네시주 초지 및 밭토양을 대상으로 토양 구성성분의 정성 정량적 분석에 필요한 측정조건을 조사하고 이를 토대로 LIBS에 의한 농도값과 기존의 화학분석법을 통해 측정한 결과를 비교하였다. LIBS 측정은 펄스형 Nd:YAG 레이저(Minilite II, Continuum, Santa Clara, CA)에서 나오는 1064 nm 에너지 파장의 광원을 시편의 플라즈마를 생성시키는데 사용하였고, 25 mJ/pulse 여기 에너지 빔을 펄스폭 35 ns, 펄스 반복 주기 10 Hz, 노출시간 10 s 동안 시료의 표면에 조사하였다. LIBS 분광은 0.03 nm의 해상력으로 200 nm에서 600 nm의 영역에서 50 m 이하로 분쇄하여 원형 펠렛 형태로 압축시킨 시료를 10 rpm의 속도로 회전시키면서 상온 상압의 실험실 조건에서 수행되었다. LIBS를 이용한 토양 중 주요한 원소의 적정 파장(nm)은 Al(I) 309.2 nm, Ca(I) 422.6 nm, Fe(I) 406.4 nm, Mg(I) 285.2 nm, Na(I) 589.2 nm, Si(I) 288.2 nm, Ti(I) 398.9 nm 이었다. LIBS의 피크강도가 물질 중 원소의 농도가 증가됨에 따라 각 원소의 특정 파장대에서 일정하게 증가되는 것으로 나타나고 있으나 표준물질의 LIBS의 신호비와 원소비를 통해 측정된 검량곡선의 상관계수($r^2$)는 0.863에서 0.977의 범위로 원소별로 상이할 뿐만 아니라 0.98에 미치지 못하였다. 또한, 토양 중 분석대상원소에 대하여 기존 ICP-AES에 의한 표준방법으로 분석된 시료의 측정값과 비교하여 상대적인 오차는 대략적으로 (-)40%에서 80%이상이며, 평균오차는 32.2%로 표준척도 20% 이상을 초과하였다. LIBS에 의한 토양분석은 토양의 조성과 입자의 크기에 따른 매질효과(matrix effect)로 표준물질의 검량곡선에서 결정계수가 낮고, 원소별 함량도 기준의 표준방법과 비교할 때 오차가 컸다. 따라서 LIBS에 의한 토양분석은 정성적인 분석 수준의 정밀도를 보였으며, 토양 매질의 영향을 최소화하기 위하여 기존의 분쇄 펠렛형 시료조제 및 회전측정 이외의 다양한 토양매질의 표준물질(standard reference material)의 확보, 새로운 전처리 방법 및 측정상 방법개선 등 신뢰성 있는 정량 분석을 위한 노력이 필요할 것으로 사료된다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1757-1763
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• 2011

In recent years, accordance to industrial development project on railway investment, adverse environmental issues of the investment, such as disputed cases about recycling and usage of Ballast Cleaner excavated soil, have been continuously increasing. It will not only enhance the regulation of soil contamination but take considerable time and cost in future. In this study, we investigated soil contamination and burnability with soil of Chungang Line, Taebaek Line, Chungbuk Line, in order to seize a possibility of recycling Ballast Cleaner excavated soil for the natural materials and substantial heat sources, which are necessary resources for cement manufacturing process. As a result of this study, It is found that Ballast Cleaner excavated soil is satisfied with a standard. The excavated soil contains a lot of cement ingredients and fossil fuel dust incurred from freight transportation, so it is expected to use for ingredients of cement and replacement of heat sources.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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• pp.189-194
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• 1998

Geochemical study was carried out to find out the distribution of metals and cyanide in soil in the vicinity of the abandoned Keum-Jung mine. Chemical analysis showed that content of As in soil around tailings exceeded 15mg/kg, Korean standard of soil contamination in the farm land. That means the contamination of soil by As is due to input of tailings. According to total decomposition of tailings, As was highly concentrated in tailings. However the water in tailings impoundment was changed to acidic and contaminated by metal and sulfate because the tailings in the top of the tailings impoundment had been oxidized. Acid mine drainage contaminated the water course in the vicinity of the paddy soils. The proper measures are required to prevent contamination of the soil and water in the vicinity of the Keum-Jung mine.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.191-194
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• 2002

Humic acid, fulvic acid and humin present in volcanic ash soil were isolated by IHSS standard procedure and their characteristics were analyzed as a basic study to evaluate the effect of humic substances on the behaviour of pollutants in contaminated surface soil. The volcanic ash soil contained 42.1 % of total organic matter based on the oven-dried soil, and humin, humic and fulvic acids corresponded to 67.5 %, 15.2 %, 7.6 % of TOM respectively. Structural informations of the humic fractions were obtained from their elemental analysis and IR, CPMAS C-13 NMR spectral analysis and the differences among them are discussed with their C/H, O/C ratios and distributions of carbon types in the molecules.