• Journal of Pharmaceutical Investigation
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• 제27권2호
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• pp.109-117
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• 1997

In order to elucidate the effect of phenobarbital (PB) on the nonlinear pharmacokinetic behavior of naproxen (NAP), we compared the dose dependent hepatic intrinsic clearance, biliary excretion and protein binding of NAP in control rats to those in the PB-pretreated rats which were intraperitoneally pretreated with PB sodium (75 mg/kg) once a day for four days. NAP was injected via femoral (1.5 mg/kg) and portal(0.25, 0.5, 1.5, 15 and 30 mg/kg) vein to the control and PB-pretreated rats, respectively. And also, we measured the plasma free fraction of NAP with the equilibrium dialysis method and the biliary excreted total amounts of NAP in both rats. Plasma free fraction of NAP was decreased in lower concentration than $150\;{\mu}g/ml$ of NAP due to PB pretreatment. In higher concentration, however, plasma free fraction was increased. These in vitro results suggest that the total protein concentration was increased but the total binding capacity of NAP to protein was decreased by PB-pretreatment. The total plasma clearance and the hepatic intrinsic clearance of NAP had similar values in both groups, respectively. And, both clearances of NAP were significantly increased by PB-pretreatment. Even though the plasma free fractions of NAP in both groups were constantly remained within the concentration range according to the increase of administration dose, the hepatic intrinsic clearances of NAP were significantly increased in both groups with the increased dose. And, the biliary excreted total amounts of NAP were significantly increased by PB-pretreatment at the lower dose, but decreased at the higher dose. These in vivo results suggest that NAP represents the uncommon nonlinear pharmacokinetic behavior that the hepatic intrinsic clearance was enhanced with the increased dose, and that PB enhances further the hepatic intrinsic clearance of NAP with the increased dose due to its enzyme induction effect.

• 자원환경지질
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• 제28권5호
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• pp.455-467
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• 1995

In order to investigate the dispersion patterns and speciations of Cu, Pb, Zn and Cd in soils, stream sediments and stream waters, geochemical studies of soil, stream sediment and stream water samples collected in the vicinity of the Shi-Heung Cu-Pb-Zn mine was carried out Cation exchange capacity measurement, size analysis, X-ray diffraction analysis and batch test were performed to select applicable soil for adsorption treatment The average content of Cu, Pb, Zn and Cd in soils collected from tailings and ore dressing plant is 1084 ppm, 2292 ppm, 3512 ppm and 29.2 ppm, respectively, and therefore, tailings and ore dressing plant site may be the major contamination sources in this study area. The mean content of Cu, Pb, Zn and Cd in stream sediments is extremely high up to 794 ppm, 1633 ppm, 2946 ppm and 25.2 ppm, respectively. Tailing particles and heavy metal ions are dispersed along the tributary system. Results from the sequential extraction analysis indicate; (1) most of Cu is bound to organic matters and sulphides, (2) fraction of Pb is mainly bound to Fe and Mn oxides. Most of Zn is largely bound to Fe and Mn oxides and residual fraction. Ion exchangeable fraction of Cd is relatively higher than those of Cu, Pb and Zn. Batch test on soils collected from the kaolinite and/or pyrophyllite mines and from the control areas was carried out to select an applicable soil samples for adsorption treatment The sample, S10, collected from the control area 2 (clay content 33.2%) shows the highest $K_d$ (distribution coefficient). Organic content in soils and several clay minerals shows relatively good correlation with $K_d$. It means that applicable soils for adsorption treatment of heavy metals show high organic and clay content.

• 한국환경과학회지
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• 제11권12호
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• pp.1299-1305
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• 2002

Thirty sediment samples of the <63${\mu}{\textrm}{m}$ fraction collected from the southwestern coast of Korea were analysed for their heavy metal (Fe, Mn, Cr, Co, Cu, Ni, Zn and Pb) concentration. The results show that sediment texture plays a controlling role on the total metal concentrations and their spatial distribution. A single lM HCl extraction procedure was used in order to assess the environmental risk of heavy metals in bottom sediments. The non-residual fraction was the most abundant pool for Mn and Pb in most samples, which means that this metals are highly avaliable in these sediments. Cr, Ni, Fe, Co, Zn and Cu were mainly associated with the residual fraction, suggesting that their concentrations are controlled significantly by transport processes with the fine particles as carriers from diffuse pollution source. Concentration enrichment ratios(CER) were calculated from the non-residual contents and their values allowed us to classify the sediments according to their environmental risk.

• 한국토양비료학회지
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• 제47권1호
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• pp.41-47
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• 2014

Agricultural soils surrounding mine areas in South Korea are often contaminated with multiple metals such as Cd, Pb and Zn. It poses potential risks to plants, soil organisms, groundwater, and eventually human health. The aim of this study was to examine the changes in phytoavailability of Cd, Cu, Pb and Zn after application with calcined eggshell (CES; 0, 1, 3, and 5% W/W) in an agricultural soil contaminated by mine tailings. The contents of Cd, Cu, Pb and Zn in soils were 8.79, 65.4, 1602, and $692mgkg^{-1}$ (aqua regia dissolution), respectively. The experiments were conducted with lettuce (Lactuca sativa L. var. longifolia) grown under greenhouse conditions during a 30-d period. $NH_4NO_3$ solution was used to examine the mobile fraction of these metals in soil. The application of CES dramatically increased soil pH and inorganic carbon content in soil due to CaO and $CaCO_3$ of CES. The increased soil pH decreased the mobile fraction of Cd, Pb, Zn: from 3.49 to < $0.01mgkg^{-1}$ for Cd, from 79.4 to $1.75mgkg^{-1}$ for Pb, and from 29.6 to $1.13mgkg^{-1}$ for Zn with increasing treatment of CES from 0 to 5%. In contrast, the mobile fraction of Cu was increased from 0.05 to $3.08mgkg^{-1}$, probably due to the formation of soluble $CuCO_3{^0}$ and Cu-organic complex. This changes in the mobile fraction resulted in a diminished uptake of Cd, Pb and Zn by lettuce and an increased uptake of Cu: from 4.19 to < $0.001mgkg^{-1}$ dry weight (DW) for Cd, from 0.78 to < $0.001mgkg^{-1}$ DW for Pb, and from 133 to $50.0mgkg^{-1}$ DW for Zn and conversely, from 3.79 up to $8.21kg^{-1}$ DW for Cu. The increased contents of Cu in lettuce shoots did not exceed the toxic level of $>25mgkg^{-1}$ DW. The mobile contents of these metals in soils showed a strong relationship with their contents in plant roots and shoots. These results showed that CES effectively reduced the phytoavailability of Cd, Pb, and Zn to lettuce but elevated that of Cu in consequence of the changed binding forms of Cd, Cu, Pb, and Zn in soils. Based on these conclusions, CES can be used as an effective immobilization agent for Cd, Pb and Zn in contaminated soils. However, the CES should be applied in restricted doses due to too high increased pH in soils.

• Nuclear Engineering and Technology
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• 제35권4호
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• pp.336-346
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• 2003

This study is intended to evaluate the dependency of TRU recycling characteristics on the neutron spectrum shift in a Pb-Bi cooled core. Considering two Pb-Bi cooled cores with the soft and the hard spectrum, respectively, various characteristics of the recycled core are carefully examined and compared with each other. Assuming very simplified fuel cycle management with the homogeneous and single region fuel loading, the burnup calculations are performed until the recycled core reached to the (quasi-) equilibrium state. The mechanism of TRU recycling toward the equilibrium is analyzed in terms of burnup reactivity and the isotopic compositions of TRU fuel. In the comparative analyses, the difference in the recycling behavior between the two cores is clarified. In addition, the basic safety characteristics of the recycled core are also discussed in terms of the Doppler coefficient, the coolant loss reactivity coefficient, and the effective delayed neutron fraction.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.363-370
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• 2005

There are approximately 2,000 metallic mines which have been abandoned in Korea. Most of the mines are located in the watershed area, which is main source of drinking water for Seoul Metropolitan area. Untreated mining wastes are remained around abandoned mines in study area. These mining wastes, flowing into farmland and stream in the downstream of abandoned mines, would cause water and soil pollution. The mining waste samples from Guedo mine, Manjung mine and Joil mine recently abandoned were collected for the evaluation of the potential of water pollution by mine waste. Index of geoaccumulation($M\"{u}ller$, 1979), fractional composition and removal efficiency of some heavy metals by different concentration of HCl treatment were analyzed. Index of geoaccumulation of Cd, Pb, Zn, Cu, Ni and Cr are 6, $4{\sim}6,\;0{\sim}6,\;4{\sim}5$, 2 and 0 respectively. Index of geoaccumulation of Cd, Pb, Zn and Cu reveals the mining wastes has high pollution pottential in the area. Organic fraction of Cu, reducible fraction of Pb, residual fraction of Ni and Zn were the most abundant fraction of heavy metals in mining wastes.

• 농약과학회지
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• 제2권2호
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• pp.29-38
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• 1998

Phenobarbital sodium(PB) 또는 3-methylcholanthrene(3-MC)이 살충제 carbofuran의 쥐에 대한 독성과 이의 독성경감효과를 구명하기 위하여 이들을 단독 또는 조합으로 경구투여한 후 쥐의 생존율을 조사하였고, 쥐에서 carbofuran 의 in vitro 대사에 미치는 영향을 구명하기 위하여 쥐 간의 추출액에 이들을 단독 또는 조합으로 처리한 후 대사산물을 조사하였다. 쥐에 대한 carbofuran의 $LD_{50}$(96hrs)은 6.9 mg/kg이었고, 주 대사산물의 독성은 3-hydroxycarbofuran > 3-ketocarbofuran > 3-hydroxycarbofuran phenol 순으로 높게 나타났으며, 모화합물보다는 그 독성이 매우 낮았다. 쥐의 생존율은 carbofuran 8.4 mg/kg만을 투여했을 때 0%이었으나 carbofuran과 PB 또는 3-MC 20 mg/kg을 각각 조합투여시 $60{\sim}80%$로 높아졌고, 60 mg/kg 투여시에는 100% 생존하여 PB 및 3-MC의 carbofuran에 대한 독성경감 효과가 매우 컸다. 간 추출액에서 in vitro 대사의 대부분은 microsomal fraction에서 이루어지고 있었다. Carbofuran 단독처리시 주 대사산물은 3-hydroxycarbofuran이었으나 carbofuran과 PB 또는 3-MC 조합처리시 3-ketocarbofuran이었다. 또한, 기질 및 처리별 대사산물의 생성율을 조사한 결과 microsomal fraction에 carbofuran 단독 및 PB 또는 3-MC와의 조합처리 모두 co-factor로서 NADP+G-6-P+G-6-P-DG 첨가시(phase I system) 가장 높았고, $105,000{\times}g$ 상징액에서는 carbofuran 단독처리의 경우 co-factor로서 NADPH+ GSH 첨가시(phase II system)에 그리고 PB 또는 3-MC와 조합처리의 경우 co-factor 중 NADPH+FAD 첨가시(phase II system)에 가장 높았다. 대사산물 생성율은 carbofuran 단독처리보다 carbofuran과 PB 또는 3-MC 조합처리에서 $2{\sim}3$배 높았다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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• pp.11-14
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• 2001

In this study, the relationship between metals (Cu, Cr, Cd, Zn. Pb, and Fe) 5 fractions and toxicity of soil samples from various contaminated sites in Korea were investigated. Metal toxicity of soils was tested using MetPLATE$^{TM}$ test kit, which is known as metal sensitive and organic insensitive. Significant amount of Fe was found in soils, and metal contents were in the order of Fe>Zn>Pb>Cu>Cr>Cd. Metal levels in organic fraction were rather high for all metals except Fe, and quite high percentages (35~79%) for residual fraction were observed for all metals. There were no significant relationships between the content of each metal fraction and toxicity which showed regression $R^2$in the range of 0.0003~0.414. However, correlation between toxicity and total metal contents showed regression coefficient $R^2$= 0.72. These results showed that the risk evaluation of metals in contaminated sites should be difficult to assess only by the contents of metal distribution because of the complexity of mixture of various metals.s.

• 자원환경지질
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• 제34권3호
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• pp.283-299
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• 2001

공주시 금흥 생활쓰레기 매립지의 중간 복토재와 차수재에서 채취한 시료에 대해 0.1N HCI 용축, 전함량 분석 및 연속추출분석을 실시하여 As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, Ti와 Zn 함량을 ICP-AES로 분석하였다. 또한, 비교를 위해 오염되지 않은 토양과 퇴적물 시료를 분석하였다. 연속추출 결과, Cu는 유기물이 용해되는 단계에서 우세하였으며, As, Ni, Sr, Ba와 Mn은 이온교환단계에서 우세하였다. 대부분의 Zn와 Mn은 산화광물, 탄산염광물 및 규산염광물과 수반되었다. Cd와 Pb는 주로 산화광물과 유기물과 수반되었다. Co, Cr, Fe와 Ti의 주요 운반자는 규산염광물이었으며, 다음으로 중요한 운반자는 산화광물이었다. 중간복토재와 차수재 시료에서 유기물과 수반된 금속의 백분율은 Cu(48%)〉Ti(42%)〉Pb(27%)〉As(25%)〉Cd(20%)의 순이었다. 연속추출결과를 근거로 추정하면, 중간복토재와 차수재에 함유된 금속의 이동도는 다음과 같이 제시되었다. : Cd〉Sr〉Ni〉Mn〉Ba〉Cu〉Pb〉Zn〉〉Co〉Ti〉Fe〉Cr. 'Geoaccmulation index'와 'enrichment factor'에 근거하면, 금흥 매립지와 농경지에서 채취한 시료들은 Cu, Ni과 Cr의 오염수준이 의미가 있었다. 이들 원소의 농집은 오염에 기인하였다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제14권1호
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• pp.68-77
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• 2009

본 연구에서는 토양수세법의 적용이 곤란한 낮은 투수성의 중금속오염이 심각한 E 유수지의 퇴적토에 대하여 동전기법의 적용성을 검토하였다. 이를 위하여 퇴적토 내 총 Cr, Pb,Cd농도 및 퇴적토의 물리화학적 특성을 조사하고, 또한 BCR 연속추출법을 통하여 동전기복원 전후 중금속들이 어떤 형태로 존재하는지를 살펴봄으로써 오염 퇴적토 내 중금속의 처리 가능부분에 대한 평가 하였다. 동전기를 적용한 결과, 총 Cr 및Pb는 양극 쪽으로 이동하였으며, 반면 Cd의 경우는, 동전기정화 전 대부분이 이온교환/탄산염 결합태를 차지하고 있어 제거가 용이할 것으로 판단되었지만, 양극 쪽 보다는 토양 체의 중간에 가장 높게 그리고 전체적으로 음극 쪽으로 이동하는 경향을 보이고 있다. 이 때, 양그 쪽의 총 Cr농도는 초기 농도보다 약 3.5배 증가한 반면, 음극 쪽에서는 대부분 제거되고 매우 낮은 경향을 나타냈다. 동전기복원전과 처리 후 퇴적토 내 중금속 결합형태를 각 구간 중 양극부분과 음극부분과 비교한 결과, 총 Cr은 잔류태가 양극과 음극 쪽에서 감소한 반면, 산화물 태는 증가한 경향을 보였다, Pb의 경우도 반응 전에 비해 반응 후 반잔류태 부분이 감소하고 산화물 태 부분이 다소 큰 폭으로 변화된 것을 나타내고 있었으며, 양극 부분 보다는 음극부분에서 분율이 증가되어있다. 그러나 Cd는 반응 전 대부분을 차지하던 이온교환/탄산염 결합 태부분은 양극과 음극부분에서 모두 감소한 것으로 나타난 반면 반응 전 무시할 정도로 낮았던 잔류 태 부분 및 산화물 태가 증가한 경향을 보였다.