• Research in Plant Disease
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• v.17 no.1
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• pp.32-37
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• 2011

Field experiments were conducted to evaluate the effectiveness of soil solarization at the Nonsan Strawberry Experiment Station, Korea in 2006 and 2008. In in vitro tests, exposure times to achieve an $LD_{100}$ of Fusarium oxysporum f. sp. fragariae were 6.6 days and 5.1 days at $45^{\circ}C$ and $50^{\circ}C$, respectively. A 100% lethal temperature was $46.7{\pm}0.1^{\circ}C$ for the same fungus. For field trials, solarization was conducted during the summer season using polyethylene mulch in a plastic house. The organic matter+calcium cyanamide+solarization treatment increased pH, organic matter, and calcium content compared to those before treatment in soil analysis, but no effect had an urea+solarization treatment. The temperatures at 10 cm depth were different in each treatment and the highest temperature was recorded from July 30 to August 10. The average temperature in organic matter+calcium cyanamide+solarization treatment at 10 cm depth was $3{\sim}4^{\circ}C$ higher than that in all the other treatments. All solarization treatments reduced the soil population of F. oxysporum f. sp. fragariae at 100% in 2008 relative to the non-treated control. All solarization treatments reduced Fusarium wilt incidence to 0% in 2006 and 2008. The effect of organic matter+calcium cyanamide+solarization against F. oxysporum f. sp. fragariae indicates that there may be future alternatives to traditional solarization for disease control as well as reducing the time needed.

• Weed & Turfgrass Science
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• v.2 no.3
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• pp.260-266
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• 2013

This study was conducted to investigate changes of vegetation and soil characteristics to tidal land of Saemangeum reclaimed land from 2010 to 2012. Soil salinity was 0.16-22.3 dS $m^{-1}$ in the first survey, while the three years later, it was decreased to 0.12-4.22 dS $m^{-1}$. Vegetations were classified as 6 families and 26 species but it was increased to 8 families and 31 species after three years. Numbers of average species in survey site were increased from 7.1 species to 10.6 species. Numbers of vegetation were increased at each survey sites except for survey site 7 : there was decreased halophyte according to decrease in the soil salinity. Biomass production was increased at low production site, and showed highest production in area of dominant vegetation as Phragmites communis. Simpson's dominance ratio(SDR) of main vegetation as Phragmites communis, Calamagrostis epigeios were increased but Suaeda maritima, Salicornia europaea, Puccinellia nipponica and Zoysia sinica were decreased.

• Korean Journal of Organic Agriculture
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• v.9 no.2
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• pp.83-99
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• 2001

This experiment was conducted to develop liquid fertilizer for leaf vegetable using the agricultural by-products such as dry chicken dropping, bone meal, rice bran, soybean oil cake and fish meal. Combination of 50% dry chicken dropping, 30% bone meal and 20% rice bran among several combinations of by-products was selected as materials for liquid fertilizer of head lettuce and cabbage. 50kg of materials with combination selected got mixed to 200ι of water, which kept under room temperature in greenhouse. EC and pH of fertilizer was stabilized after 35 days. On the decrease of bad smell during fermentation, addition of materials such as bioceramics, woody vinegar and active charcoal was not effected. And on rapid fermentation, addition of microorganisms and sugar had a little effect, but decreased the content of inorganic nutrients. Fertigation of liquid fertilizer developed on cabbage by dropping made head weight increased by 0.9kg per plant and nitrate content decreased by 276ppm in comparison with chemical fertilizer which was 3.5kg, and 2,426ppm, respectively. By use of organic liquid fertilizer developed in this experiment, yield of cabbage could be more obtained by 26% than in use of chemical fertilizer and income by 24%.

• Journal of Wetlands Research
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• v.20 no.2
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• pp.145-154
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• 2018

In this study, three pilot-scale wetland systems were built for treating stormwater runoff from asphalt road. Each of the system consists of a settling tank and a vertical flow wetland packed with 25%, 50%, and 75% woodchip as treatment media. According to the analysis of the distributions of particle size, it was found that solids ranging in size $0.52-30{\mu}m$ were predominant in the stormwater runoff. After 24-hours settling, those coarser than $20{\mu}m$ were significantly detained. Further retention, especially for the finer-sized fraction, occurred in the wetland through internal recirculation during the dry day periods. As a primary media of the wetland, woodchip showed a high filtration and attachment capacity for the particulates in pre-settled stormwater, whereas overall amount of solids in the wetland effluent increased due to the detachment of woody elements from the media. This was observed mainly during the initial 75 days of operation, and the size and detachment rate were found to be strongly related with the woodchip packing ratio. The mechanism involving woody particle detachment was modeled as a first-order form. In addition, water quality factors and operational parameters affecting the detachment were analyzed and discussed.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.567-571
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• 1997

Numbers of chemical agents which have been shown to inhibit either auxin signal transduction pathway or ethylene formation in plant cells were applied to cut flower stems of snapdragon (Antirrhinum majus L.) and their effects on the postharvest gravitropic response were studied. The chemical treatments were done by submerging either the stem base or the top part of cut flower, which involves the gravistimulus-sensitive region, for 1 h at $25^{\circ}C$. When the chemicals were supplied from the cut stem base, the gravitropic upward bending of flower stalks kept horizontally after the treatments with 20 mM CDTA or 10 mM $CoCl_2$ was comparable to that of the untreated control, but o-vanadate showed a certain degree of effectiveness for suppressing the bending response. In contrast, the direct application of those agents to the gravitropically sensitive region of cut flowers in the presence of 0.01% Triton X-100 resulted in a substantial reduction of the gravitropic response. In the case of 20 mM $CoCl_2$ treatment, almost total elimination of gravitropism without any significant deterioration of flower quality was observed. The results indicate the possibility of preparation of a protocol involving $CoCl_2$ and a proper surfactant for commercial use to suppress the gravitropic response of cut flowers during postharvest storage and transportation.

• Applied Biological Chemistry
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• v.37 no.3
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• pp.194-202
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• 1994

To study the metabolism and absorption of endosulfan in carp, $^{14}C-{\alpha}-endosulfan$ was treated with the $LC_{10}$ concentration $(4.5\;{\mu}g/L)$. In an in vivo test, endosulfan was metabolized $(65{\sim}80%)$ in tissues and endosulfan ether, endosulfan alcohol, endosulfan ${\alpha}-hydroxyether$, and endosulfan lactone were identified, indicating that those are the main metabolites of detoxification in carp. The maximum levels of $^{14}C-endosulfan$ in the head, muscle, and gut occurred after 8 hr exposure. However, the maxima reached in the liver and kidneys after 30 min and 4 hr, respectively. Radioactivity in the tissue decreased rapidly 8 hr after treatment. The total amount of $^{14}C-endosulfan$ recovered in the liver, kidneys and gut of fish was about $80{\sim}90%$ during the 8 hr treatment. The non-extractable radioactivity increased after 8 hr exposure $(27{\sim}31%)$. Endosulfan sulfate, the main degradation product in plant and mouse, was not detected during the test interval from tissues of the carp.

• Korean Journal of Food Science and Technology
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• v.17 no.6
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• pp.474-481
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• 1985

Radurization effects on fried fish meat paste with Co-60 gamma irradiation at 0-5 kGy and physicochemical aspects of the stored samples at low ($3{\pm}1^{\circ}C$, LT) and room ($10-20^{\circ}C$, RT) temperatures were investigated. The initial microbial loads of the samples were $2.2{\times}10^3/g$ in total bacterial count, $2.8{\times}10^2/g$ in yeasts & molds, and $1.0{\times}10^2/g$ in coliform group, respectively. An irradiation dose of more than 3 kGy was shown to be effective for the radurization of stored samples and there is no apparent difference between air and vacuum packaging groups. The chemical components related to the quality underwent similar changes in the nonirradiated and irradiated groups; however, as the storage time was prolonged the quality of nonirradiated samples rapidly deteriorated. Textural parameters of the samples were little affected by the applied doses, and sensory evaluations showed that 3 kGy irradiation was the optimum dose level to extend the shelf-life of fried fish meat paste up to 2 times at RT and 3 to 4 times at LT, respectively compared with the nonirradiated control.

• Korean Journal of Plant Resources
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• v.28 no.5
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• pp.641-647
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• 2015

This study was conducted to select native ground cover plants for sod culture in an organic apple orchard by estimating the effect of three native ground cover plants, Glechoma hederacea, Thymus magnus, and Ixeris stolonifera, on the soil coverage, time-periodic weed occurrence, fruit characteristics, and soil chemical properties. The plant height of G. hederace, T. magnus and I. stolonifera were 15.0 ㎝, 13.4 ㎝ and 7.2 ㎝, respectively. The dry weight of G. hederace, T. magnus and I. stolonifera were 463 ㎏/10a, 247 ㎏/10a, and 255 ㎏/10a, respectively. The plant height and dry weight of G. hederacea were higher than in the other species. T. magnus and I. stolonifera having relatively lower soil cover rate during their life cycle produced a lot of weeds in the orchard as compared with the control. In contrast, G. hederacea showed 100 percentage of ground cover in the first year, and maintained high percentage of ground cover in the growing season of ‘Tsugaru’ apple for another 2 years. When the soil was covered with G. hederacea in the orchard for 3 years, the amount of weed was only 114 ㎏/10a and number of weeding was also reduced about 33% compared with control as well as the other species. There were no differences in the tree growth and fruit characteristics between the native ground cover plants and the control; however, positive effects of native ground cover plants on soil chemical properties were found. In G. hederacea, available P₂O₄content in soils remarkably increased and was a significant difference among native species. In addition, cation (Ca, Mg and K) content in soils increased by 39% in Ca, 6% in Mg, and 11% in K at G. hederacea compared with control. These results suggest that G. hederacea could be advantageous in terms of reducing the amount of herbicide applied and the labor required for weed control, and controlling soil chemical properties; therefore, it is a good candidate for sod culture in an organic apple orchard.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.05a
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• pp.357-361
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• 2004

반복적인 실험을 통해 부추 김치에서 분리된 대부분의 유산균은 항유전독성 효과를 갖는 것으로 보인다. 이는 전에 시행되었던 각종 김치의 유산균을 이용한 항유전독성 효과 조사에서도 다른 김치유산균에 비해서 부추김치의 유산균이 항유전독성효과가 높다는 것을 통해서도 증명되었다. 유산균 섭취시에 균주가 장내의 혐기성 상태에서 존재하게 되는데 아직까지는 혐기성 상태에서 배양된 균주의 항유전독성효과가 그다지 높지 않은 것으로 보여진다. 따라서 혐기성 상태에서 배양된 항유전독성효과가 높은 균주를 찾는 것이 시급하다고 본다. 그러나 호기성 상태에서 배양된 항유전독성이 높은 균주들이 혐기성 상태에서도 배양되는 것을 확인하였고 이 균주들의 장내 생존 가능성을 예측할 수 있다. 물론 이를 뒷받침하기 위해서 이 유산균들이 위와 장내의 조건에서 생존가능하는지에 대해 pH 생존 조사를 해야 할 것이다. 또한 혐기성 상태에서 배양되었을 때에도 이 균주들이 항유전독성 효과가 있는지도 앞으로 실시되어야 할 과제일 것이다. 항유전독성 효과와 달리 항암효과에 대해서는 높은 효과를 보이지 않았지만 본래 CT-26 세포가 대장암 세포이기에 이 세포 자체의 DNA에 손상 복구율을 부여했다는 것에 의미를 둘 수 있겠다. 항유전독성효과와 항암효과가 있는 유산균의 분리를 통해 우리가 다음으로 해야 될 일은 첫째로 이 균주들에 대해 여러 가지 특성을 찾아 동정하고 둘째로 지금까지 밝혀진 결과를 in vivo상에서 검증하는 것이다. 지금까지 밝혀진 유산균은 대부분 발효 유제품에서 자라는 유산균인데 한국인이 주로 섭취하는 각종 김치나 부추김치 등에서 분리한 균주에서도 이 기능이 있음을 밝힌다면 이들의 소비에 도움이 될 것이고 또한 이 균주들을 이용해 향유전독성, 항암성 등이 있는 기능성 제품을 만들어 낼 수 있을 것이다.첨가한 햄보다 적었다.분산시키는 것으로 나타났다. 또한 고기를 단계별 복합처리로 저 allergy 처리는 단계별로 점차적으로 allergy가 감소되었다. 즉 단계별로 억제가 안되는 것부터 억제되는 처리를 복합적으로 처리한 것으로 그 단계는 천연효소처리에 인산염 처리, 여기에 초음파 처리, 마지막 단계로 3분 끓이면 억제율이 68%까지 억제되었다. 이는 단일처리시 전혀 억제를 못하는 처리를 단계별로 한 단계씩 더해가면 allergy 억제효과가 나타난다고 할 수 있겠다. 초음파 처리도 역시 저 allergy 처리 공정에 이용될 수 있는데 이것은 그 처리로 인해 새로운 알러젠이 생성될 수도 있다. 또한 복합처리로 allergy를 감소시키면 연속적이고 동시적으로 하기 때문에 원가를 절감할 수 있다.환경현안에 대한 정치경제적 접근을 외면하지 말고 교과서 저작의 소재로 삼을 수 있어야 하며, 이는 '환경관리주의'와 '녹색소비'에 머물러 있는 '환경 지식교육'과 실천을 한단계 진전시키는 작업으로 이어질 것이다. 이후 10년의 환경교육은 바로 '생태적 합리성'과 '환경정의'라는 두 '화두'에 터하여 세워져야 한다.배액에서 약해를 보였으나, 25% 야자지방산의 경우 50 ${\sim}$ 100배액 어디에서도 액해를 보이지 않았다. 별도로 적용한 시험에서, 토마토의 경우에도 25% 야자지방산 비누 50 ${\sim}$ 100배액 모두 약해를 발생하지 않았으나, 오이에서는 25% 야자지방산 비누 100배액에도 약해를 나타내었다. 12. 이상의 결과, 천연지방산을 이용하여 유기농업에 허용되는 각종의 살충비누를 제조할 수 있었으며, 방제가 조사결과 진딧물, 응애 등 껍질이 연약한 곤충의 방제에 효과적인 것으로 나타났다. 따라서 제조된 살충비누를 활용하면 환경친화적인 해

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.164-164
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• 2016

항만 및 해양 구조물은 육상과는 비교할 수 없을 정도로 가혹한 해수 환경에서 사용되며 계속적으로 부식 손상을 받는다. 따라서 강구조물이 장기적으로 안전하게 사용되기 위해서는 적절한 방식은 물론 철저한 유지관리가 필수적이다. 한편, 현재 해양환경 중 항만, 조선, 해양산업 등에 많이 이용되는 강구조물은 이에 대응하기 위하여 일반적으로 도장방식이나 음극방식이 사용되고 있다. 음극방식은 피방식체를 일정전위로 음극 분극하는 원리로써 외부전원을 인가하거나 비전위의 금속을 희생양극으로 연결하여 방식하는 방법이다. 이와같이 해수 중 음극방식을 실시할 경우 해수 중 용존하는 많은 이온들 중에서 특히 $Ca^{2+}$ 이나 $Mg^{2+}$ 이온이 탄산칼슘, 수산화마그네슘을 주성분으로하는 화합물로 형성된다. 이렇게 생성된 전착막은 산소 확산을 방지하는 물리적 장벽을 형성하고 부식율을 감소시키는 것으로 보고되고 있다. 그러나 전착막은 소지 금속과의 결합력이 불균일 함은 물론 막을 형성하는데 있어서 장시간이 소요된다는 단점이 있다. 따라서 본 연구에서는 해수 중 음극방식 응용 원리에 의해 전착막을 형성하고, 석출속도, 밀착성 및 내식특성을 향상시키기 위해 해수 중 기체를 용해시켜 제작한 막의 특성을 분석-평가하였다. 본 연구에 사용된 기판(substrate)은 일반구조용 강(SS400)을 사용하였으며, 면적은 $70mm{\times}30mm$, 두께는 1 mm로 제작하여 실험을 진행하였다. 외부전원은 정류기(Rectifier, xantrex, XDL 35-5T)를 사용하여 3 및 $5A/m^2$ 의 조건으로 인가하였고, 양극은 Carbon Rod를 사용하였다. 이때 해수에 주입한 이산화탄소의 양은 0.5 NL/min 였다. 각 조건별로 제작된 전착막에 대해 외관관찰, 석출량, 모폴로지, 조성원소 및 결정구조 분석을 실시하였고, 밀착성 및 내식특성을 평가하기 위해 테이핑 테스트(Taping Test, JIS K 5600-5-6)와 3.5 % NaCl 용액에서 전기화학적 양극 분극 시험을 진행하였다. 시간에 따른 전착막의 외관관찰 결과 전류밀도의 증가와 함께 상대적으로 많은 피막이 형성되었고, 용해시킨 기체에 의해 더 치밀하고 두터운 피막이 형성됨을 확인할 수 있었다. 성분 및 결정구조 분석 결과 $Mg(OH)_2$ 성분의 Brucite 및 $CaCO_3$ 성분의 Calcite 구조 및 Aragonite 구조를 확인하였으며, 용해시킨 기체의 영향으로 $CaCO_3$ 성분의 Aragonite 구조가 상대적으로 많이 검출되었다. 이는 해수 중 용해된 이산화탄소의 영향으로 인해 풍부한 ${CO_3}^{2-}$ 이온이 형성되고 용액 pH를 낮게 유지시켜 Ca 화합물 형성이 용이한 환경이 조성되는 것으로 판단된다. 밀착성 및 내식성 평가를 실시한 결과 해수중 용해시킨 기체에 의해 제작한 시편의 경우 견고하고 화학적 친화력이 높은 Aragonite 결정이 표면을 치밀하게 덮어 전해질로부터 산소와 물의 침입을 차단하는 역할을 하여 기체를 용해시키지 않은 $3A/m^2$ 및 $5A/m^2$ 보다 비교적 우수한 밀착성 및 내식 특성을 보이는 것으로 사료된다.