Chlorpyrifos 및 Chlorothalonil의 사과 생산단계별 잔류특성

김영숙,박주황,박종우,이영득,이규승,김장억 한국환경농학회 2003 한국환경농학회지 Vol.22 No.2

사과의 생산단계에서의 잔류허용기준 설정과 최종 소비단계에서의 안전성 평가자료로 활용하기 위하여 사과에 많이 살포되는 살충제 chlorpyrifos 및 살균제 chlorothalonil의 사과 재배기간 중 생물학적 반감기, 보관방법에 따른 잔류량 변화 그리고 부위별 잔류량 분포를 조사하였다. 사과 재배단계에서의 생물학적반감기는 chlorpyrifos 살포 후 15일, chlorothalonil 살포 후 30일까지의 잔류량 변화를 조사한 결과 chlorpyrifos 9.3일, chlorothalonil 32.2일로 나타났다. 사과의 유통과정중에서 일어날 수 있는 두 약제의 잔류량 변화는 실온저장시 chlorpyrifos 35일, chlorothalonil 56.3일이었고, 냉장 저장시에는 chlorpyrifos 120.7일, chlorothalonil 182.2일의 반감기를 나타내었다. 사과의 부의별 잔류량을 조사한 결과 chlorpyrifos의 경우 움푹 파인 부위의 과피 77.1%, 나머지 과피 22.8%, 과육 부위에서는 0.1%로 나타났고, chlorothalonil의 경우 움푹 파인 부위의 과피 85.2%, 나머지 과피 10.4%, 과육 부위에서 4.4%로 나타났다. 사과 중 두 약제의 잔류량은 대부분인 95~99%과 과피에 잔류하는 것으로 나타났다. An organophosphorus insecticide, chlorpyrifos and an arylnitrile fungicide, chlorothalonil commonly used for apple were subjected to a residual investigation under field conditions to ensure safety of terminal residues at harvest. After pesticides were applied at standard rate in apple tree for 15 days for chlorpyrifos and 30 days for chlorothalonil, persistence of their residues in apple was investigated by several interval. At harvest, residual concentrations of chlorpyrifos and chlorothalonil in apple were 1.3 and 2.4 ㎎/㎏, respectively, and the residue levels were higher than MRL, 1.0 ㎎/㎏ in Korea. As well fitted by the first -oder kinetics, biological half-lives of the pesticide residues in apple were 9.3 days for chlorpyrifos and 32.2 days for chlorothalonil. During the storage, half-lives of chlorpyrifos and chlorothalonil were 35.0 and 56.3 days at room temperature, and 120.7 and 182.8 days at 4℃, respectively. Distribution of chlorpyrifos residue in flesh, fruit skin and stalk cavity of each apple corresponded to 0.1% 22.8% and 77.1% respectively. In case of chlorothalonil, residue in flesh, fruit skin and stalk cavity was 4.4%, 10.4% and 85.2%, respectively.

상추의 생산단계별 Chlorpyrifos 및 Procymidone의 잔류허용기준 설정

김영숙,박주황,박종우,이영득,이규승,김장억 한국환경농학회 2002 한국환경농학회지 Vol.21 No.2

상추의 생산단계에서의 잔류허용기준 설정과 최종 소비단계에서의 안전성 평가자료로 활용하기 위하여 지금까지 상추수확물에서의 잔류수준과 검출빈도가 높은 것으로 알려진 살충제 chlorpyrifos 및 살균제 procymidone의 포장상태에서의 생물학적 반감기, 보관상태에 따른 잔류량 변화 그리고 세척형태에 따른 제거율을 조사하였다. 시설재배포장에서 상추중 두 약제의 살포농도별 생물학적 반감기를 측정한 결과 기준량 살포의 경우 chlorpyrifos 1.2일 및 procymidone 1.3일, 배량살포의 경우에는 chlorpyrifos 1.5일 및 procymidone 2.6일로 나타났다. 유통과정중에서 일어날 수 있는 두 가지 농약의 잔류량 변화를 알아보기 위해서 실온(20℃) 및 냉장(4℃) 상태로 보관하면서 두 약제의 잔류량 변화를 조사한 결과 반감기는 실온저장시 chlorpyrifos 3.8일, procymidone 7.2일이었고, 냉장저장시에는 chlorpyrifos 12.4일, procymidone 20.9일로 나타나 두 약제 모두 실온저장보다 냉장저장시 잔류량의 감소가 훨씬 느린 것으로 나타났다. 세척방법에 의한 잔류농약의 감소량을 조사한 결과 세제 사용시의 평균 제거율은 chlorpyrifos 48.3%, procymidone 52.6%로 나타났고, 물 사용시에는 chlorpyrifos 31.3%, procymidone 38.1%로 나타났다. Two pesticides commonly used for lettuce cultivation including chlorpyrifos and procymidone were subjected to a field residue trial to ensure safety of terminal residues in the harvest. After pesticides were applied at standard and double rates in a foliar spray, leaf persistence of their residues was investigated for 10 days prior to harvest. Even though far exceeded the tolerances, initial leaf residues were rapidly dissipated with time and remained only 0.4~7.2% of the residues in the harvest. As well fitted by the first-order kinetics, biological half-lives of the pesticide residues in lettuce leaves ranged 1.2~2.6 days. Slow dissipation of the residues in the harvest was observed during storage at room temperature and 4℃ for 7 days. Portions of dislodgeable residues which resided in detergent washings decreased as time elapsed. Patterns in dissipation and distribution of dislodgeable residues were not largely affected by the application rate of pesticides. It is concluded that timing of pesticide application, that is, pre-harvest interval would be the first factor to determine the terminal residue level in edible portions of lettuce.

경안천의 애반딧불이 서식지 오염부하량 및 생태특성

김수복,고정문,홍순상,주덕현,홍윤기,김진성,김영규 용인대학교 자연과학연구소 2011 自然科學硏究所論文誌 Vol.16 No.1

The aim of this study was to research water quality, eco-nature and firefly habitant Keung An Stream from June to July. To conserve ecosystem of firefly habitant, We must manage to have a diverse aspect of ecology and water quality. This study was to research water quality, eco-nature and firefly habitant Keung We find 11 firefly habitat in Keung An Stream. To conserve ecosystem of firefly habitant, We must manage to have a diverse aspect of ecology and water quality.

Gas-Liquid Chromatography를 이용한 사과 및 배 중의 농약 다성분 잔류분석법

박주황,김택겸,오창환,김정한,이영득,김장억 한국환경농학회 2004 한국환경농학회지 Vol.23 No.3

사과 및 배 시료에서 농약 다성분의 gas chromatography를 이용한 잔류분석법 확립을 위하여 199가지의 농약를 선정 하여 retention time 및 검출기에 따라 ECD 5 그룹 및 NPD 5 그룹의 10개 그룹으로 분류하였다. 시료의 종류에 따른 분석조건을 확립하기 위한 회수율 시험은 농약들의 log P_(ow) 값과 화학적 분류에 따라 총 18개 (ECD 11개, NPD 7개)의 농약을 선정하였다. 예비실험 후 확립된 분석방법에 따라 10개 그룹의 혼합 표준용액으로 사과 및 배에 대한 회수율시험을 행하였다. 그 결과, 총 196가지의 농약의 70%에 해당하는 사과에서 136개, 배에서 133개의 농약들에서 회수율 70에서 120%의 양호한 결과를 나타내었다. 그러나 사과에서 43개, 배에서 45개의 농약들이 70% 미만의 회수율을 보였고, fenvalerate는 120% 이상의 회수율을 나타내었으며, 사과에서 17개 및 배에서 18개의 농약들은 검출이 되지 않았다. 그러나 확립된 분석법은 SOP에 의한 신속하고 수월한 수행으로 농산물 중의 잔류농약을 검출 및 모니터링하는 목적에 적합하다고 사료된다. A rapid analytical method was developed to determine multiple pesticide residues in apples and pears using gas-liquid chromatography (GLC). The samples were extracted with water-miscible solvents and purified by cleanup procedures serially comprising liquid-liquid partition and solid-phase extraction (SPE). Each analyte was separated and determined by a high-resolution GLC equipped with electron-capture detector (ECD) and nitrogen-phosphorous detector (NPD). A total of 196 pesticides, which were previously classified into 5 groups each for ECD and NPD based on their retention behaviors on the capillary column and responses to the detector, were subjected to the recovery experiment. In compliance with the analytical criteria, 70 to 120% of recovery and less than 20% relative standard deviation, the proposed method could be successfully applied to analyze 136 and 133 pesticide residues in apples and pears, respectively, which enabled not only rapid screening but quantitation of the residues. Even though less reliability was resulted from unacceptable recovery range, rest of pesticides including 43 and 45 analytes in apples and pears, could be also detected for their identity. The proposed method, failed to cover 17 and 18 pesticides for apples and pears, which mostly showed high polarity or heat-lability but, could be suitable for fast surveilance or monitoring of fruit harvests.

높은 이온교환능력을 가지는 버미큘라이트와 술폰화된 폴리아릴렌에테르술폰으로 제조된 복합막의 연료전지 적용을 위한 특성평가

Deuk Ju Kim,Hae Young Hwang,Sang Yong Nam 한국막학회 2011 멤브레인 Vol.21 No.4

본 연구에서는 용액 캐스팅법을 이용하여 각기 다른 함량의 VMT가 첨가된 SPAES/VMT 복합막이 제조되었다. SPAES 매트릭스 내의 VMT입자 분산은 전자주사현미경으로 관찰된 평균분포에 의해 확인되었다. 1 wt%보다 적은 함량을 포함한 복합막은 고분자 매트릭스 내에 좋은 분산성을 나타내어 막의 상부층과 하부층에 매끈한 표면을 가졌다. 복합막의 함수율은 온도가 증가함에 따라 급격하게 증가되었으며 VMT는 높은 이온교환능력으로 인하여 강한 수분친화도를 가짐으로 인해 높은 모든 흡착된 수분은 bound water인 것으로 확인하였다. VMT의 함량이 1 wt%보다 적게 첨가된 복합막에서 증가된 이온전도도와 낮아진 메탄올 투과도를 확인할 수 있었다. 모든 복합막 중에서 SPAES/VMT 1.0 wt% 복합막은 선택도 측면에서 가장 뛰어난 연료전지 성능을 가졌으며 Nafion 112과 비교하여 두배 이상 우수한 값을 나타내었다. 이것은 SPAES/VMT 1.0 wt% 복합막이 직접메탄올 연료전지의 구동을 위한 가장 우수한 조건이 될것이라 사료된다. In this study, polymer composite membranes based on sulfonated poly(arylene ether sulfone) (SPAES) were prepared using a solution casting method with different amount of vermiculite (VMT) content. The dispersion of VMT particles in the SPAES matrix was confirmed by means of a scanning electron microscopy observation. The composite membrane containing less than 1 wt% of VMT has a smooth skin on the top and bottom, which means there is a good dispersion of VMT in the matrix. The water uptake of the composite membranes gradually increases as the temperature increases, and the results confirm that all the adsorbed water is bound water because VMT has a strong water affinity on account of its high cation exchange value. A composite membrane with a VMT content of less than 1 wt% increases the proton conductivity and reduces the methanol permeability. Of all the composite membranes, the membrane SPAES/VMT 1.0 has the best fuel cell performance in terms of membrane selectivity. The performance value of SPAES/VMT 1.0 is double that of Nafion 112, which suggests that SPAES/VMT1.0 could be an excellent candidate for direct methanol fuel cells.

The Improvement of the Off-site Dose Calculation Program to Enhance the Efficiency and Reliability of the Evaluation Process

Deuk-Man Kim,Seok-Ju Hwang,Cheon-Woo Kim 한국방사성폐기물학회 2022 한국방사성폐기물학회 학술논문요약집 Vol.20 No.1

The off-site dose calculation is regularly carried out at the nuclear power plants in order to evaluate off-site dose from gaseous and liquid effluent during normal operation. In 2009, the off-site calculation program (K-DOSE60) was developed in accordance with ICRP-60 by KHNP. This software needs meteorological data, gaseous and liquid effluent data, and various other input parameters to evaluate off-site dose. As a result, it takes a certain amount of time for the user to enter accurate input data and verify calculated results, and it is difficult to intuitively determine them because of providing textbased calculated results. Therefore, in this study, the improvement of the calculation program was considered so that a more reliable and effective evaluation could be performed when calculating the off-site dose. The main improvements of the off-site dose calculation program (ODCP) are as follows. First, it is developed as the network-based program to link with meteorological data, and gaseous and liquid effluent data to remove input errors and simplify data transfer. Second, through validation process of input data, input errors are eliminated. Third, the input data and calculated results are visually provided so that the user can easily determine the evaluation results. Fourth, database of input and calculated results is constructed to facilitate evaluation result history management.

Influence of Molecular Weight on Swelling and Elastic Modulus of Hyaluronic Acid Dermal Fillers

Deuk Yong Lee(이득용),Cheolbyung Cheon(전철병),Siwon Son(손시원),Young-Zu Kim(김영주),Jin-Tae Kim(김진태),Ju-Woong Jang(장주웅),Seok-Soon Kim(김석순) 한국고분자학회 2015 폴리머 Vol.39 No.6

분자량이 다른 세종류 히알루론산(HA)에 1,4-butanediol diglycidyl ether(BDDE)가 가교된 hyaluronic acid(HA)를 첨가하여 하이드로겔을 제조하고 HA 분자량에 따른 팽윤도와 탄성계수의 효과를 조사하였다. 최종 투석 후 잔류 BDDE 양은 0.5 ppm 이하이었다. 비가교된 분자량이 큰 HA에서 최대 팽윤도가 관찰되었다. 팽윤도는 비가교 HA 양과 가교도에 각각 비례와 반비례하였다. 1.0 w/v% BDDE 가교 HA와 HA(1368 kDa)를 혼합한 monophasic 하이드로젤의 탄성계수는 152~325 ㎩이었다. 15% 가교 HA(687 kDa)과 85% HA(1368 kDa)로 구성된 biphasic 하이드로젤의 탄성계수는 178 Pa이었다. 1,4-Butanediol diglycidyl ether (BDDE) crosslinked hyaluronic acid (HA) suspended in three different HAs (697, 1058, 1368 kDa) were prepared to investigate the effect of HA molecular weight on swelling property and elastic modulus of the hydrogels. The amount of the residual BDDE after final dialysis was less than 0.5 ppm. The highest swelling ratio was observed for the uncrosslinked HA having the largest molecular weight. The expansion capacity of HA rose with increasing the amount of pure HA and was inversely proportional to the crosslinking degree due to an increased number of coiled HA chain interactions. Elastic modulus (G’) of monophasic fillers having different ratios of 1.0 w/v% BDDE crosslinked HAs to pure HA (1368 kDa) were within 152 and 325 ㎩. 178 Pa was observed for the biphasic fillers consisting of 15% crosslinked HA (697 kDa) nanoparticles suspended in 85% of uncrosslinked HA (1368 kDa).

Experimental and modeling study of blended membranes for direct methanol fuel cells

Kim, Deuk Ju,Park, Chi Hoon,Tocci, Elena,Nam, Sang Yong Elsevier 2018 Journal of membrane science Vol.564 No.-

<P><B>Abstract</B></P> <P>The dynamics of hydronium ions and methanol molecules in hydrated SPAES and blend membranes are investigated via molecular dynamics simulations using the COMPASS force field. In addition to calculating the diffusion coefficients as a function of the hydration level, an amorphous cell with a specific composition of H<SUB>2</SUB>O molecules and H<SUB>3</SUB>O<SUP>+</SUP> determined from the experimental data is constructed and tested. The water and methanol diffusion coefficients are considerably smaller at lower hydration levels and room temperature. The diffusion coefficient of the water and methanol molecules increases with increases in the hydration level, and this is in good agreement with experiment data. Analysis of the pair correlation functions supports the experimental observations of the membrane performance with hydration related to the water and methanol diffusion behavior in hydrated SPAES and blend membranes.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Investigation on dynamics of hydronium ions and methanol molecules. </LI> <LI> Calculation of diffusion coefficients as a function of hydration level. </LI> <LI> Incorporation of hydrophobic domains effect to transport behavior of membrane. </LI> <LI> The calculated diffusion coefficient is in good agreement with experiment. </LI> </UL> </P>

Characterization of sulfonated silica nanocomposite electrolyte membranes for fuel cell.

Kim, Deuk-Ju,Nam, Sang-Yong American Scientific Publishers 2014 Journal of nanoscience and nanotechnology Vol.14 No.12

<P>Sulfonated poly(arylene ether sulfone) (SPAES) and sulfonated silica (silica-SO3H) prepared via sol-gel reaction are used as an organic polymer matrix and inorganic nanoparticles. The contents of the silica-SO3H particles in the composite membranes are controlled at 0.5, 1, 2, 3 and 5 wt.% in order to evaluate the appropriate content for high proton conductivity. Randomly dispersed silica particles are obtained from all composite membranes as a result of the hydrophilic domains in the polymer and silica-SO3H. In this study, the optimum silica-SO3H content for high proton conductivity is 3 wt.% in fully hydrated conditions and 0.5 wt.% in low humidity conditions.</P>

Review of New Regulatory Guidelines in Relation to the Off-site Dose Calculation

Deuk-Man Kim,Seok-Ju Hwang,Cheon-Woo Kim 한국방사성폐기물학회 2022 한국방사성폐기물학회 학술논문요약집 Vol.20 No.2

In 2022, new regulatory guidelines were announced in relation to the off-site dose calculation (ODC), and accordingly, measures to improve the off-site does calculation program (ODCP), kdose60, were reviewed. The main consideration is, first, that if multiple nuclear facilities are operated on the same site, the boundaries of the restricted areas shall be set as the overlapping outer boundaries of the restricted areas determined by calculation for each nuclear facility. Second, the external exposure caused by direct radiation from a number of nuclear facilities in the same site must be partially or fully applied depending on the facility and site characteristics. Third, the dose conversion coefficient should be evaluated by checking whether the effect of the daughter nuclides is properly reflected. Fourth, the soil contamination period is a factor to consider that radioactive substances deposited on the surface, such as particulate nuclides, affect residents over a long period of time. Fifth, due to the recent construction of Shin-Kori Units 5 and 6, there is a change in the site boundary of the Kori/Saeul site, so as the site boundary is expanded, it is required to add an exposure dose assessment point due to gas effluents and change the exposure dose assessment point according to crop intake. Therefore, through this study, the direction for improving the ODCP will be prepared by reviewing the recent revision of the regulatory guidelines.