• Applied Biological Chemistry
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• 제45권1호
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• pp.30-36
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• 2002

제초제 butachlor의 어류농축 계수를 결정하기 위하여 동위원소 표지화합물과 비표지 화합물을 사용하여 송사리 체내에서의 농축시험을 수행하였다. 비표지 화합물을 사용하였을 때 송사리 체내에서의 butachlor농축은 0.036ppm농도에서 40시간 경과 후 가장 높은 어류생체 중 296의 생체 농도/수중 농도$(C_f/C_w)$ 비율을 보였고, 64시간 이후부터는 평형상태에 이르렀으며, 이 때의 bioconcentration factor(BCF)는 87이었다. 또한, 0.0036 ppm도에서는 18시간 경과 후 가장 높게 축적되어 $C_f/C_w$의 비율이 169였고, 60시간 이후에는 평형상태에 도달하여 BCF 값은 51이었으며, 이 두 농도로부터 결정된 BCF 값은 $69{\pm}28$이었다. $^{14}C-butachlor$의 송사리 체내에서의 농축 및 배설은 총 $^{14}C$를 기준으로 하였을 때 17시간 경과 후 가장 높은 539 $C_f/C_w$의 비율을 나타내었고, 74시간 이후부터는 평형상태에 이르러 BCF는 394로 계산되었다. 그러나 14C-butachlor의 양만을 고려했을 때 $C_f/C_w$의 비율은 총 흡수량의 1/3이었고, 2/3은 $^{14}C-butachlor$의 대사물 이었으며, 평형상태에서의 $^{14}C-butachlor$의 BCF는 334로 계산되었다. 또한, 송사리 체내로부터의 $^{14}C-butachlor$의 배설은 12시간 이내에 50% 이상이, 30시간이 되면서 90% 이상이 배설되었다. 생체 내에서의 대사물은 아주 극성이 강한 대사물들로서 TLC상에서 $R_f$이 0.43인 대사물 M-II와 $R_f$값이 0.7인 대사물 M-III로 확인되었고, 신선한 사육수로 어체내 대사산물을 배설시켰을 때 $R_f$ 값이 0.25인 대사물 M-I을 확인하였다. M-I은 어체내에서 배출되는 과정중의 주요한 중간 대사물 임을 예상할 수 있었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권6호
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• pp.56-66
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• 2016

Generally, the contribution of crop-intake pathway (CIP) is remarkable in human health assessment (HHA) of heavy metal contamination. Although the crop exposure concentrations (Cp) should directly be used for calculating the average daily dose (ADD) of CIP, the soil exposure concentration (Cs) multiplied by soil-crop bio-concentration factor (BCF) has frequently been used instead of using Cp values. Thus, the BCF values are significant in the HHA, and care should be taken to ensure the reasonable acquisition of BCF values. Meanwhile, the BCF values are known to be significantly affected by analytical methods. Nevertheless, they have been calculated from the concentrations of soil and crop analyzed by only one method: total digestion (aqua regia extraction). For this reason, this study was initiated to seek appropriate soil analysis methods for effective computation of the ADD of CIP. The concentrations of 5 metal contaminants (As, Cd, Cu, Pb, and Zn) in 127 soil samples obtained from 4 abandoned metal mine areas were analyzed by several methods including total digestion and partial digestions using 0.1/1 N HCl, 1M $NH_4NO_3$, 0.1 M $NaNO_3$, and 0.01M $CaCl_2$. The heavy metal concentrations in 127 crop samples (rice grains) were analyzed by total digestion as well. Using the concentrations of soils and crops, the BCF values of each contaminant were calculated according to the kind of soil extraction methods applied. Finally, the errors between Cp and $C_s{\times}BCF$ were computed to evaluate the relevance of each method. The results indicate that the partial extraction using 0.1 N and 1 N HCl was superior or equivalent to total digestion. In addition, the 0.1M $NaNO_3$ method combined with total digestion is recommended for improving the reliability of BCF values.

• Korea-Australia Rheology Journal
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• 제21권1호
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• pp.1-12
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• 2009

This paper reports the suitability of a domain decomposition technique for the hybrid simulation of dilute polymer solution flows using Eulerian Brownian dynamics and Radial Basis Function Networks (RBFN) based methods. The Brownian Configuration Fields (BCF) and RBFN method incorporates the features of the BCF scheme (which render both closed form constitutive equations and a particle tracking process unnecessary) and a mesh-less method (which eliminates element-based discretisation of domains). However, when dealing with large scale problems, there appear several difficulties: the high computational time associated with the Stochastic Simulation Technique (SST), and the ill-condition of the system matrix associated with the RBFN. One way to overcome these disadvantages is to use parallel domain decomposition (DD) techniques. This approach makes the BCF-RBFN method more suitable for large scale problems.

• 한국식품위생안전성학회지
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• 제18권4호
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• pp.251-256
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• 2003

본 연구는 zebrafish를 실험어류로 하여 국내에서 혼합제로 사용되고 있는 dichlovos와 phosalone을 선정하여 단독 및 혼합폭로시 생물농출계수와 배설속도상수를 측정함으로써, 두 농약의 공존이 개별농약의 생물농축성에 미치는 영향을 알아보고자 하였다. Dichlorvos와 phoslone의 혼합폭로시(dichlorvos : 0.55${\mu}g$/ml, phosalone : 0.01 ${\mu}g$/ml) zebrafish 체내에서 dichlorvos의 농축정도는 6시간에 정류상태에 도달하여 72시간까지 거의 일정하였으며 단독폭로시 (12시간)보다 더 빠르게 정류상태에 도달하였다. 6시간에서 72시간 사이의 BCF평균값은 0.80(n=5)으로 단독 폭로시의 12시간에서 72시간 사이의 BCF평균값 0.74(n=4)보다 더 높게 측정되었다. 배설속도상수는 $0.12h^{-1}$으로 단독 폭로시와 차이가 거의 없었다. Dichlorvos와 phosalone의 혼합폭로시(dichlorvos: 0.55${\mu}g$/ml, phosalone : 0.01${\mu}g$/ml) zebrafish 체내에서 phosalone의 농축정도는 단독폭로시와 같이 12시간에 정류상태에 도달하여 72시간까지 거의 일정하였고, 12시간에서 72시간 사이의 BCF평균값은 53.89(n=4) 로 단독폭로시의 BCF평균갑 48.88(n=4)보다 더 높게 측정되었다. 배설속도상수는 단독폭로시와 같이 6시간 안에 어류체내에서 phosalone이 모두 배출되어 구하지 못했다. 두 농약(dichlorvos, phosalone)의 혼합폴로시의 BCF평균값이 단독폭로시의 BCF평균값이 단독폴로시의 BCF평균값보다 더 높게 나왔으나, 각 실험시간대(6, 12, 24, 48, 72시간)의 BCF실험값을 t-test로 분석한 결과 phosalone의 48시간을 제외하고는 두 농약의 단독폭로와 혼합폴로시의 BCF값에는 유의한 차이가 없었다(p<0.05), 이상의 결과를 종합해 볼때, dichlorvos와 phosalone을 zebrafish에 혼합폭로시 개개 농약의 생무농축성과 배설속도상수에는 유의한 영향을 미치지 않는 것으로 나타났다.

• 한국환경보건학회지
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• 제23권2호
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• pp.72-82
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• 1997

This study was performed to investigate the effect of co-existence of BPMC, carbaryl and chlorothalonil on the short-term bioconcentration factor in Carassius auratus(goldfish). The fishes were exposed to the combined treatment of BPMC, carbaryl and chlorothalonil (0.05 ppm+0.05 ppm+0.005 ppm, 0.05 ppm+0.05 ppm+0.010 ppm, 0.05 ppm+0.10 ppm+0.005 ppm, 0.10 ppm+0.05 ppm+0.005 ppm, 0.10 ppm+0.10 ppm+0.005 ppm) for 3 and 5 days, respectively. BPMC, carbaryl and chlorothalonil in fish and in test water were extracted with n-hexane and acetonitrile. GC-ECD was used to detect and quantitate BPMC, carbaryl and chlorothalonil. 3-day and 5-day bioconcentration factors(BCF$_3$ and BCF$_5$) of each pesticide were calculated from the quantitation results. The depuration rate of each pesticide-from the whole body of fish was determined over the 72-h period after combined treatment.The results were as follows: BCF$_3$ values of BPMC were 4.163, 4.011, 4.122, 4.750 and 4.842 when the concentration of BPMC+ carbaryl+chlorothalonil in combined treatment were 0.05 ppm+0.05 ppm+0.005 ppm, 0.05 ppm+0.05 ppm+0.010 ppm, 0.05 ppm+0.10 ppm+0.005 ppm, 0.10 ppm+0.05 ppm+0.005 ppm and 0.10 ppm+ 0.10 ppm+0.005 ppm. BCF$_5$ values of BPMC were 3.465, 3.270, 3.472, 3.162, 4.227 and 4.157, respectively, under the above conditions. While BCF$_3$ values of carbaryl were 4.583, 4.642, 4.571, 3. 637 and 3.529, respectively, and BCF$_5$ values of carbaryl were 3.932, 3.797, 3.843, 4.293 and 4.132, respectively, under the conditions. While BCF$_3$ values of chlorothalonil were 2.024, 3.532, 2.213, 2.157 and 2.271, respectively, and BCF$_5$ of chlorothalonil were 6.712, 7.013, 6.457, 6.694 and 6.597, respectively, under the conditions. Depuration rate constants of BPMC were 0.019, 0.018, 0.020, 0.022 and 0.021 when the concentration of BPMC+carbaryl+chlorothalonil in combined treatment were the same as above. And depuration rate constants of carbaryl were 0.030, 0.029, 0.030, 0.029 and 0.031, respectively, under the same condition of pesticide mixtures. While depuration rate constants of chlorothalonil were 0.004, 0.004, 0.003, 0.004 and 0.003, respectively, under the same condition. It was observed that no significant differences of BCFs and concentrations of the compounds in fish extracts, test water between combined treatment and single treatment. It was considered that no appreciable interaction at experimental concentrations was due to low concentrations, near environmental level, 0.005-0.1 ppm. Coexistence of BPMC, carbaryl and chlorothalonil had no effect on depuration rate of each pesticide and depuration rate of chlorothalonil was investigated 1/8 and 1/6 slower than those of carbaryl and BPMC in combined treatment. It is similar result in comparison with single treatment. Therefore, it is considered that the persistence of chlorothalonil in fish body would be higher than those of carbaryl and BPMC.

• 한국가축번식학회지
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• 제27권1호
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• pp.69-75
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• 2003

본 연구의 목적은 inbred 마우스 (C57BL/6J)의 수정란을 이용하여 형질전환마우스를 생산할 때, 수정란이식의 효율성을 증진시키기 위한 것이다. C57BL/6J 및 BCF1 마우스로부터 과배란처리 방법에 의해 수정란을 얻고, DNA를 1 세포기 수정란에 미세 주입한 다음, 1세포기 또는 2 세포기의 수정란을 가임신된 마우스의 한쪽 또는 양쪽 난관에 각각 이식하였다. 1세포기의 수정란을 0.75 d.p.c. 가임신된 마우스의 한쪽 난관에 이식했을 때, 임신율이 C57BL/6J는 68.8$\pm$7.83%, BCF1은 48.3$\pm$14.22% 이었고, 이식한 수정란 당 산자의 발달율은 C57BL/6J가 11.9$\pm$5.51%, BCF1은 10.5$\pm$8.03%로 성적이 저조하였다. 그러나, 2세포기의 수정란을 0.5 d.p.c. 가임신된 마우스의 양쪽 난관에 이식했을 때, 임신율이 C57BL/6J는 94.4$\pm$9.64%, 13CFl은 100$\pm$0% 이었고, 이식한 수정란 당 산자의 발달율은 C57BL/6J가 22.1 $\pm$0.4%, BCF1은 21.8$\pm$0.38%였다. 따라서 C57BL/6J 마우스의 2세포기 수정란을 0.5 d.p.c. 가임신된 마우스의 양쪽 난관에 이식하는 것이, BCF1마우스와 유사한 성적을 얻어 경쟁력이 있는 것으로 판단되었다. 이러한 결과에 영향을 미치는 인자가 여러 가지 있을 것으로 판단되지만, C57BL/6J 마우스의 2세포기 수정란을 0.5 d.p.c.가임신된 마우스의 양쪽 난관에 이식하는 방법이 다른 방법보다 형질전환마우스를 생산하는데 효율성이 더 높은 것으로 본 실험에서 확인되었다.

• 한국환경보건학회지
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• 제28권2호
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• pp.131-139
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• 2002

초기생애단계의 일본송사리를 실험어류로 사용하여 TCDD와 PCB 126의 생물농축정도를 비교 측정하였고, TCDD와 PCB 126의 체외 배설에 대한 동태학적 특성을 비교 분석하였다. 생물농축실험은 초기생애단계의 새끼치어 및 어린 물고기에 TCDD와 PCB 126을 여러 농도로 물에 용해시켜 96시간 동안 정체된 상태로 폭로시킨 후 생물농축계수(BCF)와 지방-표준화한 생물농축계수(BCF$_{L}$)를 측정하였다. TCDD와 PCB 126의 일본송사리 초기생애단계의 새끼치어 및 어린 물고기에서 측정된 96-h BCF값 및 96-h BCF$_{L}$값은 폭로된 농도와 상관없이 비슷하게 나타나 반면, 생체크기가 클수록 그 값은 작게 나타났다. 일본송사리 새끼치어, 어린 물고기, 성어의 생체 내 총 지방함량은 각각 5.7, 4.2, 4.6%로 측정되었다. 체외배설 동태실험은 어린 물고기에 TCDD와 PCB 126을 3가지 농도롤 물에 용해시켜 96시간 동안 정체된 상태로 폭로시킨 후, flow-through장치로 공급되는 맑은 물로 옮겨 42일간 사양하면서 0, 7, 14, 21, 28, 42일에 생체 내 TCDD와 PCB 126 잔류량을 측정하여 분석하였다. 배설은 1차 반응속도론적으로 이루어졌으며 한 구획모형보다 두 구획모형이 더 적합한 것으로 분석되었다. 두 구획모형을 사용한 분석에서 TCDD와 PCB 126의 체외배설 반감기(t$\frac{1}{2}$) 및 배설속도상수($\beta$)는 각각 27.2일과 32.3일 및 0.025/d와 0.021/d로 측정되었다.

• 한국식품위생안전성학회지
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• 제14권2호
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• pp.146-152
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• 1999

The present study was performed to investigate the bioconcentration of BPMC, chlorothalonil, dichlorvos and methidathion. The BCFs(bioconcentration factors) and depuration rate constants for four pesticides in zebrafish(brachydanio rerio) were measured under semi-static conditions(OECD guideline 305-B) in a concentration of one-hundredth of the 96 hours LC50 of each pesticide at the equilibrium condition. The results obtained are summarized as follows : The BCFs of BPMC, chlorothalonil, dichlorvos and methidathion were 1.44$\pm$0.09, 2.223$\pm$0.063, 0.81$\pm$0.08 and 5.53$\pm$0.13, respectively. Depuration rate constants of BPMC, chlorothalonil, dichlorvos and methidathion were 0.028, 0.015, 0.220 and 0.152, respectively. The concentrations of BPMC, dichlorovs and methidathion in zebrafish reached an equilibrium in 3 days, and the equilibrium of chlorothalonil was reached after 14 days. Depuration rate of dichlorvos was the fastest followed by methidathion, BPMC and chlorothalonil. The lower BCF of BPMC was due to its relatively high KOW, slow KDEP, and low SW and VP, compared to chlorothalonil and methidathion. The BCF of chlorothalonil was much lower than that excepted on the basis of high KOW, slow KDEP, SW and VP. The reason is that the experimental concentration for chlorothalonil is 1/100~1/1000 lower than that of BPMC, dichlorvos and methidathion. The BCF of dichlorvos was lower than that of other pesticides due to its very rapid KDEP, very high VP and SW, and very low KOW. The BCF of methidathion was higher than that of other pesticides due to its very low VP and SW. Therefore, these data suggest that physicochemical properties of pesticides may be important in the bioconcentration.

• 충청수학회지
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• 제31권1호
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• pp.29-42
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• 2018

In this paper, we investigate the stability of two functional equations f(ax+by + cz) - abf(x + y) - bcf(y + z) - acf(x + z) + bcf(y) - a(a - b - c)f(x) - b(b - a)f(-y) - c(c - a - b)f(z) = 0, f(ax+by + cz) + abf(x - y) + bcf(y - z) + acf(x - z) - a(a + b + c)f(x) - b(a + b + c)f(y) - c(a + b + c)f(z) = 0 by applying the direct method in the sense of Hyers and Ulam.

• 한국환경보건학회지
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• 제27권2호
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• pp.108-118
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• 2001

This study was performed to investigate the bioconcentration of IBP, methidathion and piperophos. The BCFs(bioconcentration factor), depuration rate constants for three pesticides in zebrafish(Brachydanio rerio) were measured by OECD guideline 305. The concentration of test pesicides were one-hundredth and one-thousandth concentration of 96-hrs L $C_{50}$ in accordance with OECD guideline 305. The results obtained are summarized as follows: The average BCF values of IBP were 5.31(n=4) and 7.30(n=4) at one-hundredth and one-thousandth concentration of 96-hrs L $C_{50}$ . The average BCF values of methidathion were 8.72(n=4) and 11.25(n=4), the average BCF values of piperophos were 34.30(n=4) and 42.60(n=4). Depuration rate constants of IBP were 0.09( $h^{-1}$ ) and 0.08( $h^{-1}$ ), half-life of IBP were 7.70 and 8.66 at each tested concentration. The concentrations of IBP in zebrafish at low and high concentrations rapidly decreased after 12(0.243$\mu\textrm{g}$/g) and 12 hours(0.040$\mu\textrm{g}$/g). Depuration rate constants of methidathion were 0.40( $h^{-1}$ ), half-life of methidathion were 1.73 at one-hunderdth and of 96-hrs L $C_{50}$ , repectively. The concentrations of methidathion in zebrafish at high concentrations rapidly decreased after 6 hours(0.18 $\mu\textrm{g}$/g). Depuration rate constant of low concentration was no measured because methidathion in zebrafish was depurated in 6 hours. Depuration rate constants of piperophos sere 0.15( $h^{-1}$ ) and 0.44( $h^{-1}$ ), half-life of piperophos were 4.62 and 1.58 at each tested concentration. The concentrations of piperophos in zebrafish at los and high concentrations rapidly decreased after 12(0.26$\mu\textrm{g}$/g) and 6 hours(0.015 $\mu\textrm{g}$/g). It was suggested that high BCF of piperophos was due to high Kow(octanol-water partition coefficient). The possibility of bioconcenration was not likely to be high because of its $K_{DEP}$(depuration rate constant) in the evniroment. It was suggested that low BCF of methidathion showed lowest Kow as well as the most rapid $K_{DEP}$. Therefore, the possibility of bioconcentration was not occured in the enviroment. It was suggested that the BCF dtermined for IBP was lower than that of other pesticides due to high Sw(water solubility), show $K_{DEP}$. Therefore, IBP revealed little bioconcentration effect on in aquatic ecosystem.ystem.