• 한국물환경학회지
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• 제26권1호
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• pp.156-159
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• 2010

Peroxide is used frequently to provide electron acceptors to aerobes for the purpose of in situ bioremediation of contaminated soil/sediment. In this study, oxygen release rate of peroxides and factors affecting on dissolution and diffusion of oxygen into pore water were evaluated. Peroxides studied in this study were magnesium peroxide ($MgO_2$), calcium peroxide ($CaO_2$), and sodium percarbonate ($Na_2CO_3{\cdot}1.5H_2O_2$). $Na_2CO_3{\cdot}1.5H_2O_2$ showed the highest oxygen release rate per unit mass and the shortest release duration time among three peroxides. A simple first-order decay model for predicting the release rate of oxygen from peroxide into pore water was presented and used to fit the experimental data. The first order oxygen release rate constants k for $MgO_2$, $CaO_2$ and $Na_2CO_3{\cdot}1.5H_2O_2$ were 0.45 /hr, 3.22 /hr and 134 /hr, respectively. If $MgO_2$ was mixed with clay, oxygen release rate was lowered significantly mainly due to limitation of contact area and diffusion, implying that oxygen can be provided to the indigenous aerobes for the extended period of time.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권3호
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• pp.83-91
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• 2015

Mine soil contamination by high levels of metal ions that prevents the successful vegetation poses a serious problem. In the study presented here, we used the microbial biocatalyst of urease producing bacterium Sporosarcina pasteurii or plant extract based BioNeutro-GEM (BNG) agent. The ability of the biocatalysts to bioremediate contaminated soil from abandoned mine was examined by solid-state composting vegetation under field conditions. Treatment of mine soil with the 2 biocatalysts for 5 months resulted in pH increase and electric conductivity reduction compared to untreated control. Further analyses revealed that the microbial catalysts also promoted the root and shoot growth to the untreated control during the vegetation treatments. After the Sporosarcina pasteurii or plant extract based BNG treatment, the microbial community change was monitored by culture-independent pyrosequencing. These results demonstrate that the microbial biocatalysts could potentially be used in the soil bioremediation from mine-impacted area.

• 자원환경지질
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• 제32권1호
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• pp.43-51
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• 1999

In order to remediate hazardous waste site, a process of electrokinetically purging chemicals from saturated soil is examined by laboratory experiments. Electrokinetic soil remediation is one of the most promising soil decontamination processes that habe igh removal efficiency and time-effectiveness in low-permeability soils such as clay. Being combined with several mechanisms-electromigration, elec troosmosis, diffusion and electrolysis of water, electrokinetic soil processing can remove non-polar organics as well as ionic contaminants. The objectives of this study are; 1) the exploration of the feasibility of electrokinetic soil processing on the removal of heavy metals, 2) the investigation of applicability to the tailing-soils in aban doned mining area, 3) the examination of effects of soil pH and conductivity on the transport phenomena of elements in soils, and 4) the investigation of the applicability of the ionexchange membrance to the efficient collection of heavy metals removed from contaminated soils. With the result of this study, it is suggested that the removal efficiency is significantly influenced by applied voltage & current, type of purging solutions, soil pH, permeability and zeta potentials of soil. Although further study should be needed, it is possible to collect removed heavy metals with ion-exchange membrance in cathode compartment.

• 환경생물
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• 제29권1호
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• pp.23-30
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• 2011

In this study, the Comet assay (evaluation of DNA damage) used the fish hepatocellular carinoma cell, PLHC-1, was tried to the sediment extract obtained from freshwater to understand its applicability as a tool for monitoring sediment toxicity. In parallel, induced EROD (7-ethoxyresorufin- O-deethylase) activity and DNA damage (TEM values) in PLHC-1 cells were measured for establishing the tandem endpoints of the PLHC-1cell test to test the ecotoxicity of sediment. Among several study sites in a small river passed through downtown and industrial park area, one of them, site B, showed a higher level of EROD activity and DNA damage than other sites. It indicates that a tandem endpoints of PLHC-1 cells could be useful tools for assessing the toxicity of sediment. The sensitivity of Comet assay with PLHC-1 cells was a little higher than that with a blood cell of frog tadpoles to the solvent extract of sediment. According to the results, a PLHC-1 cell-Comet assay could be used as a useful tool for evaluating ecotoxicity of the freshwater sediment. In addition, more detailed studies are needed to the contaminated site.

• 한국수산과학회지
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• 제43권5호
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• pp.547-550
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• 2010

Jinhae Bay is a typical aquaculture farm with active fisheries. However, it has been contaminated by the development of a major city and industrial area, and has therefore diminished in value as a fishing ground. To preserve the continuing productivity of the ocean, we have to estimate fisheries resources. To analyze the fisheries resources in Jinhae Bay, we evaluated the Fisheries Productivity Index (FPI). The FPI is composed of the Total production ($T_p$), Total amount ($T_a$), and Production of edible protein ($E_p$), nitrogen ($N_p$) and phosphorous ($P_p$). To calculate the FPI, we used Annual statistics on cooperative sales of fishery products data from 1979 to 2004 and the Food composition table. The results of the FPI were as follows. $T_p$ ranged from 70,235 tons to 113,556 tons and $T_a$ ranged from 107,004 million won to 373,776 million won. $E_p$ ranged from 8,124 tons to 13,357 tons, $N_p$ ranged from 1,965 tons to 3,273 tons, and $P_p$ ranged from 168 tons to 276 tons. According to the FPI, maximum fisheries productivity occurred in 1994, when $T_a$, $E_p$, $N_p$ and $P_p$ were at their highest values.

• 농업과학연구
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• 제36권1호
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• pp.57-61
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• 2009

The invasive pest Brontispa longissima(Coleoptera: Chrysomelidae), native to Indonesia and Papua New Guinea, has extended its distribution to Australia, Asia and Pacific islands and caused serious leaf damages of the coconut palm Cocos nuciferain the invaded regions. Although biological control using parasitic wasps has successfully reduced population density and leaf damage levels, this pest and its natural enemies have not been efficiently producedin conventional methods using young leaves of C. nucifera. In the present study, we examined suitability of plants easily available in Thailand and Japan for mass rearing of this pest to develop effective mass rearing system of this pest. Mature, green leaves of the palms were also suitable for immature development and adult reproduction of this pest. Since mature leaves of C. nucifera are more abundant and less contaminated with fungus than the unopened leaf buds, mature leaves could be a promising plant diet for mass rearing of B. longissima. Ornamental palms such as Hyophorbe lagenicaulis and Washingtonia filifera were also suitable for immature development and reproduction of B. longissima. Away from palms, the cattail Typha spp. can sustain immature development and adult reproduction of B. longissima. In the area where C. nucifera is rare or not available, W. filifera or Typha spp. would be good food plants for mass rearing of this pest.

• 한국지능시스템학회논문지
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• 제23권2호
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• pp.178-183
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• 2013

In this study, we proposed a method for electroencephalogram (EEG) classification using invariant CSP at special channels for improving the accuracy of classification. Based on the naive EEG signals from left and right hand movement experiment, the noises of contaminated data set should be eliminate and the proposed method can deal with the de-noising of data set. The considering data set are collected from the special channels for right and left hand movements around the motor cortex area. The proposed method is based on the fit of the adjusted parameter to decline the affect of invariant parts in raw signals and can increase the classification accuracy. We have run the simulation for hundreds time for each parameter and get averaged value to get the last result for comparison. The experimental results show the accuracy is improved more than the original method, the highest result reach to 89.74%.

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1638-1642
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• 2010

Mesoporous carbon CMK-3s with different textural properties have been used for the adsorption of phenol to understand the necessary physicochemical properties of carbon for the efficient removal of phenol from contaminated water. The kinetic constants (both pseudo-second order and pseudo-first-order kinetics) increase with increasing pore size of carbons. The maximum adsorption capacities correlate well with micropore volume compared with surface area or total pore volume even though large pore (meso or macropore) may contribute partly to the adsorption. The pore occupancies also explain the importance of micropore for the phenol adsorption. For efficient removal of phenol, carbon adsorbents should have large micropore volume and wide pore size for high uptake and rapid adsorption, respectively.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2001년도 추계종합학술대회
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• pp.300-303
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• 2001

The first 7 years of altimeter data from the TOPEX/POSEIDON (T/P) were analyzed to study the surface circulation and its variability in the East Asian Marginal Seas. Long term averaged T/P sea level time series data where compared with in situ sea level measurements from a float-operated type tide gauge around of south Korea and Japan. T/P data are a large contaminated by 60-day tidal aliasing effect, very near the alias periods of M2 and S2. When this 60-day effect is removed, the data agree well with the tide gauge data with 4.6 cm averaged RMS difference. The T/P derived sea level variability reveals clearly the well-known, strong current-topography such as Kuroshio. The T/P mean sea level of North Pacific (NP) was higher than Yellow Sea (YS) and East Sea (ES). The T/P sea level valibility, with strong eddy and meandaring, was the largest in eastern part of Japan and this variability was mainly due to the influence of bottom topography in Kuroshio Extention area.

• 한국식품과학회지
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• 제11권3호
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• pp.176-181
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• 1979

전국에서 수집된 1976년산 현미(玄米)시료 112점중 수은과 카드뮴의 농도를 분석, 비교한 결과는 다음과 같다. 1) 현미중 수은 농도의 검출 범위는 불검출${\sim}0.310\;ppm$이었으며 전국평균치는 0.053 ppm이었다. 다만 김포(金浦)지역에서의 시료는 평균치의 $5{\sim}6$배에 이르고 있었다. 2) 현미중 카드뮴 농도의 검출 범위는 흔적${\sim}0.029\;ppm$이었으며 전국 평균치는 0.021 ppm으로서 카드뮴으로 오염되었다고 생각되는 특정 지역은 발견되지 아니하였다.