• Title/Summary/Keyword: 침투이행성

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Simulation of Effects of Permeability on Seepage between Two Heterogeneous Layers of Sea-dike (방조제 이질층의 투수성이 제체 침투에 미치는 영향에 대한 모의 분석)

  • Lee, Haeng-Woo;Chang, Pyoung-Wuck;Son, Young-Hwan;Kim, Seong-Pil
    • Journal of The Korean Society of Agricultural Engineers
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    • v.48 no.6
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    • pp.79-85
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    • 2006
  • A simulation was done to analyze the seepage problems due to seawater intrusion through the embedded rock layers on heterogeneous layers of sea-dike. Numerical analysis with SAMTLE(developed by author) was done by taking various relative permeability $ratio(R_r/R_e)$. These results showed, when the sed-dike is newly designed, operated, and maintained considering the safety of sea-dike in seepage problems, these embankment materials are prudently chosen. The permeability of the soil materials, within the range of salinity management in freshwater, is comparatively high, however, the permeability of rock materials for bottom rock layer is low. Therefore, when the relative permeability $ratio(R_r/R_e)$ is bellow 10 it is safety in seepage problems of sea-dike.

Evaluation of Susceptibility of Western Flower Thrips (Frankliniella occidentalis) and Garden Thrips (F. intonsa) to 51 Insecticides (꽃노랑총채벌레와 대만총채벌레에 대한 51종의 살충제 감수성 평가)

  • Cho, Sung Woo;Kyung, Yejin;Cho, Sun-Ran;Shin, Soeun;Jeong, Dae Hun;Kim, Sung Il;Park, Geun-Ho;Lee, Seung-Ju;Lee, Young-Su;Kim, Min-Ki;Jo, In-Jun;Koo, Hyun-Na;Kim, Hyun Kyung;Kim, Gil-Hah
    • Korean journal of applied entomology
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    • v.57 no.3
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    • pp.221-231
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    • 2018
  • The susceptibility of the western flower thrips, Frankliniella occidentalis and garden thrips, Frankliniella intonsa was evaluated using 51 commercial insecticides. 15 kinds of insecticides which showed more than 90% mortality against both thrips, F. occidentalis and F. intonsa was selected. Many active ingredients were misused and abused in commercial mixture formulation insecticides. Since the F. intonsa was more susceptible than F. occidentalis, it was considered that both thrips can be controlled by insecticides that showed insecticidal activity on the F. occidentalis. Lethal time ($LT_{50}$ and $LT_{95}$), systemic toxicity and residual toxicity of selected insecticides were compared. Both chlorpyrifos WP and chlorpyrifos + diflubenzuron WP revealed the fastest toxicity within 2 h ($LT_{95}$), while spinetoram WG revealed the slowest toxicity as 62.3 h ($LT_{95}$). Chlorfenapyr SC showed toxicity at foliar and drenching application while spinetoram WG was toxic only in foliar application. Chlorfenapyr SC showed residual effect at 3, 5, 7, 10, 15 days after treatment and both benfuracarb WG and chlorpyrifos WP showed residual effect at 3 days after treatment. As a result of treatment of selected insecticides for field population of F. occidentalis, the population collected from horticultural crops showed lower susceptibility than the population collected from vegetable crops.

Property of action of new insecticide, flupyrazofos against diamondback moth, Plutella xylostella (신규 살충제 flupyrazofos의 배추좀나방에 대한 작용특성)

  • Kim, Gil-Hah;Moon, Sun-Ju;Chang, Young-Duck;Cho, Kwang-Yun
    • The Korean Journal of Pesticide Science
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    • v.2 no.3
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    • pp.117-125
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    • 1998
  • Flupyrazofos (O,O-diethyl-O-(1-phenyl-3-trifluoromethyl-5-pyrazoyl)thiophosphoric acid ester) is a new organo-phosphorous insecticide. Flupyrazofos has exhibited excellent activity against diamondback moth (Plutella xylostella, DBM), and it is highly activity against rice armyworm(Pseudaleta separata) and cotton caterpillar(Palpita indicae). Flupyrazofos has then revealed outstanding both rapidity and residual action for DBM, although no systemic actions were observed and no cross-resistances were found to the resistance strains (Op-R, Py-R, IGR-R). Also, susceptibilities of five local strains to flupyrazofos were similar to those of the susceptible strain. These results indicate that flupyrazofos has considerable potential for controlling diamondback moth, rice armyworm and cotton caterpillar in field.

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Attempted Synthesis of Carboxin Derivative through Ring Expansion Reaction on Solid Phase (고체상에서 환팽창 반응에 의한 카르복신 유도체의 합성시도)

  • Hahn, Hoh-Gyu;Bae, Su-Yeal;Nam, Kee-Dal
    • The Korean Journal of Pesticide Science
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    • v.9 no.3
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    • pp.185-190
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    • 2005
  • Solid phase synthesis of 16, which is a derivative of the first systemic fungicide, carboxin 1 was described. Reaction of 1,3-oxathiolane derivative with solid resin of 4-hydroxy-3-nitrobenzophenone 6 gave 9 in 82% yield. Oxidation of sulfur in the solid 1,3-oxathiolane 9 by MCPBA followed by a ring expansion reaction under the acid catalyst afforded the corresponding dihydro-1,4-oxathiin derivative 12. Treatment of the solid 1,3-oxathiolane 9 with p-methoxyaniline resulted in 1,3-oxathiolane 14, 1,3-oxathiolane sulfoxide 15, dihydro-1,4-oxathiin 16, and acetoacetanilide derivative 17 in 41%, 35%, 14%, 10% yields, respectively.

Control Effects of 3-(4-Hydroxyphenyl)-propionic Acid Isolated Xenorhabdus nematophila K1 against Phytophthora Blight and Anthracnose of Red Pepper (Xenorhabdus nematophila K1 대사물질 3-(4-hydroxyphenyl)-propionic acid의 고추 역병과 탄저병에 대한 방제 효과)

  • Cheon, Wonsu;Kim, Doyeon;Kim, Yonggyun;Hong, Yong Pyo;Yi, Youngkeun
    • Research in Plant Disease
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    • v.19 no.3
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    • pp.208-215
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    • 2013
  • 3-(4-Hydroxyphenyl)-propionic acid (HPP) is a bacterial metabolite synthesized and released by an entomopathogenic bacterium Xenorhabdus nematophila K1. In this study, the control efficacy of HPP was tested against Phytophthora blight and anthracnose of red pepper plants. HPP suppressed mycelial growth of Phytophthora blight and anthracnose pathogens. Under natural sunlight condition, HPP maintained the antifungal activity on the diseases for at least twenty five days. The antifungal activity was not decreased even in the condition of soil-water. It was proved that HPP was able to penetrate the roots and travel upward of the red pepper plants. When HPP suspension was applied to soil rhizosphere before transplanting the red pepper seedlings or was regularly sprayed to the foliage of the plants with ten days interval, it resulted in significant reduction of the disease occurrences (Phytophthora blight and anthracnose) without any phytotoxicity. These results suggested that HPP can be developed to a systemic agrochemical against Phytophthora blight and anthracnose of red pepper plants.

Analysis of Urban Runoff Reduction according to SSP Climate Change Scenarios Applying LID Element Technology : focus on the Cheonggyecheon Basin (LID 요소기술을 적용한 SSP 기후변화 시나리오에 따른 도시 유출량 저감 분석_청계천유역을 대상으로)

  • Eui Hyeok Yoon;Bae Sung Lee;Sang Yeon Yoo;Min Ho Lee;Ye Chan Shin
    • Proceedings of the Korea Water Resources Association Conference
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    • 2023.05a
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    • pp.386-386
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    • 2023
  • 본 연구는 청계천 유역에 대하여 미래 저영향개발을 고려한 도시 수문순환 변화를 전망하였다. 새로운 기후변화 시나리오에 대하여 유출량 변화 특성 및 저영향개발 요소기술의 적용을 통하여 유출량 감소 변화를 분석하기 위하여 18개의 GCM을 선정하였고, 이를 통하여 생산된 강수량 자료를 활용하였다. 그리고 기후변화 시나리오의 새로운 개념인 SSP 시나리오를 적용하였다. SSP2-4.5 및 SSP5-8.5 시나리오에 대하여 2046년~2075년 기간에 대한 강수량의 변화는 현재 대비 SSP2-4.5 시나리오에서 13.9%와 SSP5-8.5 시나리오에서 20.6%의 증가가 전망되었다. 그리고 미래 기간에 대하여 저영향개발을 고려하여 SWMM을 이용하여 유출량의 저감 변화를 모의하였다. 그 결과 GCM별 또는 저영향개발 요소기술의 조합에 따라 유출량 저감 차이는 있으나 투수성포장 및 침투도랑을 유역 전체에 적용했을 경우 가장 효과가 좋았다. 그 효과는 투수성포장은 SSP2-4.5 시나리오에서는 14.2%, SSP5-8.5 시나리오에서는 13.5%의 유출량 저감 효과를 나타내었고, 침투도랑은 SSP2-4.5에서 14.0%, SSP5-8.5에서 14.2%씩 유출량이 저감되는 것으로 분석되었다. 이 연구는 약 10년 이상 소요되는 도시 수문순환 계획의 이행을 고려하여, 앞으로 20년 후의 기후에 대한 도시 수문순환의 변환을 전망하였다. 그러므로 향후 우리나라 수도 서울의 도시 수문순환 등의 지속가능성 확보에 기여 할 수 있을 것으로 판단된다.

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Evaluation in ELISA for the Residue Analysis of Metalaxyl in Crops (작물체중 Metalaxyl 의 잔류분석을 위한 ELISA의 응용)

  • Lee, Kang-Bong;Im, Geon-Jae;Jung, Young-Ho;Suh, Yong-Tack
    • Korean Journal of Environmental Agriculture
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    • v.14 no.1
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    • pp.23-27
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    • 1995
  • The cross-reactivities of antibody derived from rabbit immunized with metalaxyl-HSA conjugate were identified to 44% and 28% for metalaxyl acid and metolachlor respectively. The detection range of metalaxyl in competitive ELISA was 5 ppb to 5 ppm. The recoveries of metalaxyl in ELISA for 6 crops; potato, sesame, pepper, cabbage, cucumber and onion was ranged 77.5-103.6%. In this test, CV% were calculated below 10% except for sesame sample as shown 21.5%.

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Control Efficacy of Fungicide Injection on Oak Wilt in the Field (살균제 나무주사를 이용한 참나무 시들음병 방제 효과)

  • Son, Su-Yeon;Seo, Sang-Tae;Park, Ji-Hyun
    • Research in Plant Disease
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    • v.20 no.4
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    • pp.295-298
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    • 2014
  • Oak wilt caused by Raffaelea quercus-mongolicae was first noticed in South Korea in 2004 and, ever since, its distribution and damage have been increasing. To screen a fungicide effective for oak wilt control by tree injection, laboratory and field experiments were conducted. Ten fungicides and one antibiotic were examined in vivo for their effectiveness in restricting the growth of R. quercus-mongolicae and R. quercivora (Japanese oak wilt pathogen) isolates. To the Korean isolates of R. quercus-mongolicae, chlorothalonil showed the highest fungicidal effects, followed by benomyl and propiconazole. To the Japanese one, propiconazole was highest in the fungicidal effectiveness, followed by benomyl and bitertanol. Propiconazole was selected for field-testing of its control efficacy because it showed good fungicidal effects in vitro and systemic activity. The control efficacy in the field was 87.5% in the first year of injection and 66.7% in the second year, indicating the fungicidal effects last at least over one year.

Comparative Toxicities of Selected Acaricides against the Twospotted Spider Mite(Tetranychus urticae Koch) to Establish the Screeing System for New Acaricidal Chemical Compounds (스크리닝체제 확립을 위한 점박이응애에 대한 몇가지 살비제의 약효 비교)

  • 조점래;최용호;박노중;조광연
    • Korean journal of applied entomology
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    • v.32 no.2
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    • pp.123-128
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    • 1993
  • The comparative toxicities of selected acaricides against the twospotted spider mite, Tetranychus urticae, were investigated. The ovicidal and adulticidal activities of selected acaricides were examined under different developmental stages. Fenpyroximate showed high activity throughout all developmental stages of mites. The oviposition inhibition effect of fenpyroximate was more highly effective than that of cyhexatin. At 100 ppm concentration, the effect of fenpyroximate on the residual oviposition inhibition was persistant during 25 days with 85% level, while the effect of cyhexatin gradually decreased, and then decreased to 40% at 25 days after treatment. Fenpyroximate at 100 ppm showed 100% knockdown activity within 3 hour while cyhexatin showed only 91% knockdown activity within 24 hours after treatment. Most of selected acaricides had no systemic activity, but metasystox at 800 ppm had 100% of the systemic activity at 24 hours after treatment. For the influence of temperature on the activity, fenpyroximate showed stable activity and no temperature-dependent in comparison with other selected adaricides.

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Uptake of the Fresh and Aged Residues of Carbofuran by Rice Plants from Soil (침투성(浸透性) 살충제(殺蟲劑) Carbofuran 토양(土壤) 잔류물(殘留物)의 벼에 의(依)한 흡수(吸收))

  • Lee, Jae-Koo;Kyung, Kee-Sung;Wheeler, W.B.
    • Korean Journal of Environmental Agriculture
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    • v.8 no.2
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    • pp.103-118
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    • 1989
  • In order to investigate the uptake of the systemic insecticide, carbofuran, 2,3-dihydro-2,2-dimethyl-7-benzofuranyl-N-methyl(arbamate) residues, fresh and aged, by rice plants, they were grown for 42 days in soils containing freshly treated (T-1), 3-month-aged (T-2), and 6-month-aged residues (T-3). The amounts of $^{14}CO_2$ evolved from $^{14}C-carbofuran$ during the 3-and 6-month aging in soil (temp. $22{\pm}1^{\circ}C$ ; moisture, 50% of the maximum water-holding capacity) were 8.9 and 26.7% of the original radioactivity applied, respectively. Mineralization of $^{14}C-carbofuran$ in soil to $^{14}CO_2$ during 42 days of rice growing was 4.4% (T-1), 11.0% (T-2), and 15.7 (T-3). The methanol extract of the 3-and 6-month-aged soils revealed that 3-keto carbofuran phenol (2,3-dihydro-2,2-dimethyl-3-oxo-7-benzofuranol) was the major metabolite, where as 3-hydroxy carbofuran (2,3-dihydro-2,2-dimethyl-3-hydroxy-7-benzofuranyl-N-methylcarbamate) turned out to be the major metabolite in the shoots by the enzymatic cleavage of the possible conjugate present in the methanol extract. Volatilization of $^{14}C-carbofuran$ in soil during 3-and 6-month-aging, and 42 days of rice growing was 0.026, 0.05, and 0.012-0.018% of the applied radioactivity, respectively. The $^{14}C-radioactivity$ which was absorbed from the soils by rice plants during 42 days of the growing period and persisted in rice plant tissues was 26.8, 21.4, and 10.3% in T-1, T-2, and T-3, respectively. The non-extractable bound residues were 8.3, 37.9, and 54.6% of the originally applied carbofuran in T-1. T-2, and T-3, respectively. The small translocation of $^{14}C-radioactivity$ in T-3 upwards suggests that major metabolite 3-keto carbofuran phenol is conjugated in roots and the low recovery in T-1 indicates the loss of carbofuran from the shoots.

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