• 제목/요약/키워드: copper sprays

검색결과 4건 처리시간 0.016초

약제별 및 살포시기별 자두 검은점무늬병 방제효과 (Control Efficacy of Different Types of Chemicals with Different Spraying Schedules on Plum Bacterial Black Spot)

  • 류영현;이중환;권태영;김승한;김동근
    • 식물병연구
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    • 제18권4호
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    • pp.349-353
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    • 2012
  • 자두 검은점무늬병은 Xanthomonas arboricola pv. pruni에 의한 세균성 병해로 과실표면에 검은 반점형태의 병징이 발생하여 과실 상품성을 저하시켜 자두 재배농가에 큰 경제적 손실을 초래하는데 이러한 자두 검은점무늬병에 대한 효과적인 약제 방제체계를 개발하기 위하여 몇 종의 화학약제와 살포체계를 구성하여 휴면기중에는 동제 약제를 그리고 과실생육기중에는 항생제계열 약제를 살포하였는데 과실생육기중에서의 항생제계열 약제살포는 휴면기중의 동제 약제살포보다 높은 방제효과를 나타내었다. 자두의 개화만개 10일 후부터 10일 간격으로 3회의 항생제계열 약제살포는 93%의 높은 방제가를 얻을 수 있었는데 비해서 휴면기중의 동제 약제살포는 26-42%의 낮은 방제가를 얻는데 그쳤다. 또한 항생제계열 약제의 처음 살포시기가 개화만개 후 20일이나 30일 보다는 개화만개 후 10일에서 더 높은 방제효과를 얻을 수 있었다.

FC-77의 분무냉각 비등열전달 특성에 관한 연구 (Study on Boiling Heat Transfer of FC-77 in Spray Cooling)

  • 김영찬
    • 한국분무공학회지
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    • 제12권4호
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    • pp.179-184
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    • 2007
  • The boiling heat transfer was experimentally investigated for the FC-77 sprays impacting a square heated test surface in a downward direction. Full cone spray nozzles were employed for the spray cooling experiment, and experiments were made under the test conditions of $Q=3.32{\times}10^{-6}{\sim}2.30{\times}10^{-5}\;m^3/s$, ${\Delta}T_{sub}=20{\sim}70^{\circ}C$. Also, heat transfer measurements were made using the copper block of $10{\times}10\;mm^2$ test area heated by nine cartridge heater. From the experimental results, correlation between the Nusselt number and Reynolds number based on droplet-flow-rate was developed. The correlation shows good predictions with ${\pm}30%$ error for FC-77.

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PF-5052의 분무냉각 비등열전달에 관한 실험적 연구 (Experimental Study on Boiling Heat Transfer of PF-5052 in Spray Cooling)

  • 김영찬
    • 대한기계학회논문집B
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    • 제32권12호
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    • pp.938-944
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    • 2008
  • The boiling heat transfer was experimentally investigated for the PF-5052 sprays impacting a square heated test surface in a downward direction. Full cone spray nozzles were employed for the spray cooling experiment, and experiments were made under the test conditions of Q=$3.32{\time}10^{-6}{\sim}\;12.98{\time}10^{-6}m^3/s$, ${\Delta}T_{sub}=5{\sim}25^{\circ}C$. Also, heat transfer measurements were made using the copper block of $10{\time}10mm^2$ test area heated by nine cartridge heater. From the experimental results, correlation between the Nusselt number and Reynolds number based on droplet-flow-rate was developed. The correlation shows good predictions with ${\pm}30$ % error for PF-5052.

Management of Citrus Canker in Argentina, a Success Story

  • Canteros, B.I.;Gochez, A.M.;Moschini, R.C.
    • The Plant Pathology Journal
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    • 제33권5호
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    • pp.441-449
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    • 2017
  • Citrus canker is an important bacterial disease of citrus in several regions of the world. Strains of Xanthomonas citri type-A (Xc-A) group are the primary pathogen where citrus canker occurs. After Xc-A entered the Northeast of Argentina in 1974, the disease spread rapidly from 1977 to 1980 and then slowed down and remained moving at slow pace until 1990 when it became endemic. Citrus canker was detected in Northwest Argentina in 2002. This paper presents the main steps in the fight of the disease and the management strategies that have been used to control citrus canker at this time. We think the process might be usefull to other countries with the same situation. Results from more than 40 years of research in Northeast (NE) Argentina indicate that we are at the limit of favorable environment for the disease. The severity of citrus canker is greatly affected by the environment and El $Ni{\tilde{n}}o$ Southern Oscillation (ENSO) phenomenon which causes cyclic fluctuations on the disease intensity in the NE region. Weather-based logistic regression models adjusted to quantify disease levels in field conditions showed that the environmental effect was strongly modulated by the distance from a windbreak. Production of healthy fruits in citrus canker endemic areas is possible knowing the dynamics of the disease. A voluntary Integrated Plan to Reduce the Risk of Canker has been in place since 1994 and it allows growers to export unsymptomatic, uninfested fresh fruit to countries which are free of the disease and require healthy, pathogen free fruits. The experience from Argentina can be replicated in other countries after appropriate trials.