• The Korean Journal of Pesticide Science
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• v.6 no.4
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• pp.293-299
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• 2002

This experiment was conducted to elucidate the effects of fruit bagging on the amounts of pesticide residues on/in pears with two pesticides, chlorpyrifos 25% WP, and penconazole 5% WP, and two pear cultivars, Niitaka and Hwangeum-bae. Residues of chlorpyrifos and penconazole in bagged pears were only $0.4{\sim}27%$ of those in non-bagged one. Residues of both pesticides in bagged and non-bagged pears were steeply reduced in the field but slowly reduced during storage. Residues of chlorpyrifos were more in the peel than in the flesh, while penconazole in bagged pear was evenly distributed in the peel and flesh. Chlorpyrifos was evenly distributed in outer bag and inner bag irrespective of bag materials, while most of penconazole was found in outer bag rather than in inner bag. To produce safer pear from pesticide residues, removal of bag before storage is recommended.

• Aerospace Engineering and Technology
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• v.10 no.1
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• pp.1-12
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• 2011

The error of onboard propellants mass which is mostly occupied in total mass of launch vehicle and The error of residual affect the performance of launch vehicle seriously. In other words, the errors directly cause the error of total impulse. Therefore, optimization of performance of launch vehicle can be achieved by the minimization of the residual. For minimizing the residuals, the active control for completely depleting the propellants and the calculation method using probability for minimizing the residuals have been researched. In this paper, the added fuel was calculated for minimizing the residual and the minimized residual was predicted by the presented method.

• Journal of Food Hygiene and Safety
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• v.6 no.2
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• pp.83-87
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• 1991

Beef, pork and chicken on the market were analyzed for determination of tetracyclines residue and decomposition of tetracyclines by heating were studied. The content of oxytetracycline was trace in chicken A, 0.09 mg/kg in C and trace in beef C, pork A and B, but in the other samples was not detected oxytetracycline. Chlortetracycline residue was 0.14, 0.02 and 0.01 mg/kg in chicken A, C and beef B respectively. In HPLC analysis, two peaks of 8.1 and 9.0 min of retention time were found from beef and pork and expected to be component of meat, and because of same retention time, the one of 9.0 min interrupted determination of tetracycline. But those were not found in chicken, therefore the residue was 0.01 mg/kg in sample A. The residue were degradated rapidly by heating of roast, but slightly by that of boiling.

• Journal of Food Hygiene and Safety
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• v.1 no.2
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• pp.163-169
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• 1986

소, 돼지, 닭 및 염소의 근육, 지방조직 및 내장부위에서 11가지 유기염소계 잔류농약을 분석하여 다음과 같은 결과를 얻었다. 1. 육류시료 모두에서 검출된 유기염소계의 잔류량은 $\alpha$-BHC, $eta$-BHC, pp'-DDE, Heptachlor epoxide, ${\gamma}$-BHC순으로 검출되었고, Heptachlor, pp'-DDE 및 pp'-DDD는 극미량 내지는 흔적 정도 검출되었고 Drins류는 검출되지 않았다. 2. Total BHC 잔류량의 범위는 소의 경우 0.389ppb~1.111ppb로 평균 0.713ppb였고, 돼지는 0.139ppb~0.150ppb로 평균 0.631ppb였으며 닭은 0.312ppb~0.80ppb로서 평균 0.517ppb였다. 그리고 염소의 경우에는 0.238ppb~1.134ppb로써 평균 0.586ppb의 수준이었다. 3. 육류별 잔류량은 소, 돼지, 염소, 닭의 순서이고 부위별 잔류량은 지방조직이 가장 많았고 그 다음이 근육, 그외 부위별 잔류량의 차이는 거의 없었다.

• Korean Journal Plant Pathology
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• v.12 no.3
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• pp.307-315
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• 1996

토마토 잎에 집적된 triflumizole 잔류량 동태에 미치는 온도 영향과 Cladosporium fulvum에 대한 triflumizole의 살균효과를 구명하였다. 8주간 키운 토마토 식물체에 triflumizole을 분무 살포한 후 식물생장용 항온실에서 키우면서 4가지 온도 조건을 처리하였다. 주기적으로 토마토 잎을 채취하여 HPLC 방법을 이용하여 triflumizole의 잔류량을 조사하였다. Triflumizole 잔류량의 경시적 동태는 약제살포후 적산온도를 독립변수로 사용하는 지수적 감소 몸형으로 나타낼수 있었으며, 이는 triflumizole의 잔류성이 온도 영향을 크게 받는다는 것을 뜻한다. 경기도 농촌진흥원에 위치한 토마토 비닐하우스에서 수행한 실험에서 얻은 자료를 이용하여 평가한 결과 이 모형의 타당성이 인정되었다. Triflumizole의 약효에 대한 in vitro 실험 결과, 이 살균제는 C. fulvum의 균사 생장과 포자형성을 뚜렷이 억제하였으며, 잎곰팡이병 방제를 위해서는 토마토 잎에 집적된 triflumizole 잔류량이 최소한 10 ppm 이상이 되어야 할 것으로 추측된다. 본 연구에서 연구된 지수적 감소 모형은 토마토 잎에 집적된 triflumizole 잔류량을 추정하는데 활용될 수 있으며, 실용적인 측면에서 볼 때, 토마토 잎곰팡이병을 효과적으로 방제하는데 필요한 triflumizole의 최소 잔류량을 식물체에 유지하기 위하여 triflumizole을 살포해야 할 시기를 결정하는데 활용될 수 있다.

• Korean Journal of Environmental Agriculture
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• v.14 no.3
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• pp.312-318
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• 1995

Residues of benfuresate in rice and oxolinic acid in Chinese cabbage were determined through the field experiments in order to establish the safe use and the maximum residue limit(MRL) of these pesticides in Korea. The herbicide benfuresate powder was sprayed into the paddy field with a level of 0.6kg(active ingredient)/ha and rice (Oryza sativa L.) was grown. At harvest, residues of benfuresate in brown rice and stem were analyzed using gas chromatograph. The residue of oxolinic acid in Chinese cabbage (Brassica campestris subsp. napus var pekinesis MAKINO) was analyzed using HPLC after foliar-spraying this fungicide into the cabbages at a level of 15kg/ha. The recovery efficiencies of benfuresate and oxolinic acid were 87-89% and 90-95%, respectively. The respective residues of benfuresate in rice and oxolinic acid in Chinese cabbage were in the range of 0.27-0.46 mg/kg and 0.23-1.53kg/kg. Residual concentrations of these pesticides in crops increased with the increased application frequencies, followed the first-order kinetics and linearly decreased with time. The highest residue of 1.53 mg/kg of oxolinic acid was observed when this fungicide was sprayed six times until three days prior to harvest, but this level was far lower t㏊n 5 mg/kg, which is the maximum residue limit(MRL) set by FAO/WHO.

• Korean Journal of Environmental Agriculture
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• v.23 no.3
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• pp.142-147
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• 2004

Dissipation pattern of tebuconazole was evaluated by establishing application methods of the fungicide, paper-bagging of grape during growth and washing of grape after harvest. Application times increased from three to five resulted in high levels of residues in grape. Tebuconazole in grapes was present in different residual patterns with periods after final treatment ranging from 7 to 25 days. Significant differences in the residual patterns were also found when tebuconazole was treated during three different application periods, possibly due to meteorological condition and/or grape growth during each period. At the range from 2.5 g to 7.5 g of grape granules, residues were higher in small-sized grape than in big-sized grape and were mostly distributed on the peel of the grapes. Paper-bagging was a critical factor for reducing the fungicide residue on the peel. flesh of bagged and no-bagged grape had very low level of residues, 0.01 mg/kg and 0.05 mg/kg, respectively. Residues on grape was effectively eliminated with the washing methods suggested, a consecutive sinking-washing system Using of detergent solution during washing showed maximum residue reduction from grape. The washing methods showed effective action on the removal of lower content providing complete elimination, or almost, of the residues.

• Applied Biological Chemistry
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• v.23 no.3
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• pp.184-188
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• 1980

A survey of pesticide and copper residues of the citrus orchard soil was conducted during October 1979-June 1980 in Jeju, Seogwipo county. The citrus orchards were classified into five groups according to different cultivated period; 5 year orchard, 10 year orchard, 15 year orchard, 20 year orchard, and 30 year orchard. Each of the above samples was divided again to three layers of soil depth; the surface layer$(0{\sim}10cm)$, the middle layer $(10{\sim}20cm)$, and the bottom layer $(20{\sim}40cm)$. In this experiments, Kelthane and Akar, as well as copper residues were detected in all soil samples. Residue levels of above chemicals were increased in soils of orchard with longer cultivation periods, and at the same time, decreased with soil depth. The residues of those ranged as follows; a) from trace to 1.359ppm in Kelthane, b) from trace to 0.925ppm in Akar, and c) from trace to 40.734ppm in copper. It is noted that the average residues of Kelthane was 0.251ppm, Akar, 0.120ppm, and that of copper was 2.168ppm, respectively.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.228-235
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• 2014

The residue levels of flonicamid and its metabolites, 4-(trifluoromethyl)nicotinic acid (TFNA) and N-4-(trifluoromethyl)nicotinoyl glycine (TFNG) in sweer pepper were investigated to examine the residual characteristics of analytes for 87 days after pesticide application. The pesticide was applied once at recommended dosage and double dosage by foliar sprays and the samples of fruits and leaves of sweet pepper were collected for each treatment. The residues of flonicamid in all of fruits and leaves decreased gradually over time, while the residue levels of TFNG metabolite exhibited tendency that increased for long periods and thereafter decreased. Total flonicamid residual concentrations containing metabolites residues in fruit samples increased consistently until 30 days post-application and higher residue levels than residues at 1 day post-application were detected from 30 day to 87 day after treatment. The residue pattern observed in fruit could be explained by the movement of TFNG from leaves to fruits of plant. Such residual characteristic was similarly found in samples treated both recommended dosage and double dosage.

• The Korean Journal of Pesticide Science
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• v.8 no.1
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• pp.30-37
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• 2004

This study estimated the correlation between surface area/weight ratios and pesticide residues in two varieties of tomato, mini tomato and tomato. The ratios of surface area/weight of mini tomato and tomato were $2.15cm^2g^{-1}$ and $1.00cm^2g^{-1}$ respectively. Pesticide residues were measured with four kinds of pesticide, chlorothalonil WP, chlorothalonil SC, oxadixyl WP, thiophanate-methyl WP. Ie residue amount of mini tomato was $1.4\sim2.4$ times higher than those in tomato regardless of the application date and frequency. The ratios of surface area/weight on tomato varieties played a key role for determining pesticide residue.