• 한국물환경학회지
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• 제26권3호
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• pp.518-524
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• 2010

Continuous removal of organic matters (CROM) using freshwater bivalve Anodonta woodiana was operated to evaluate the effect of water current on the water quality improvement (clearance) of eutrophic lake. The CROM system comprised three treatment steps such as flow control, treatment and analysis, and operated at the two different currents ($24L\;h^{-1}$ and $48L\;h^{-1}$) with mussels at density of $312.5indiv.\;m^{-2}$ for 12 consecutive days. Water quality including suspended solids (SS) and chlorophyll-a (Chl-a) was daily measured at the same time. Results indicate that although both the system strongly decreased the concentration of SS and chl-a, a slow CROM system was more effective to diminish the SS contents than a fast CROM system; 82% and 66%, respectively (ANOVA, P<0.0001). Clearance rates, based on chl-a, were also significantly higher in a slow system than a fast system (ANOVA, P<0.0001), although the mussel mortality was conversely. In both systems, there showed a remarkable excretion of dissolved inorganic nutrients (i.e. $NH_3-N$ and $PO_4-P$), while a slow CROM system was higher than a fast system, significantly (ANOVA, P<0.0001). Therefore, it may suggest that a slow current CROM system is more suitable to maximize the efficacy of water quality improvement, but further study is needed to diminish the mortality of mussel and to reuse the nutrient released during the operation.

• Archives of Pharmacal Research
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• 제28권9호
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• pp.1092-1096
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• 2005

Huperzine A-loaded microspheres composed of poly(D,L-lactide-co-glycolide) were prepared by an O/w emulsion solvent evaporation method. The characterization of the microspheres such as drug loading, size, shape and release profile was described. The in vitro release in the initial 7 days was nearly linear with $10\%$ released per day. Thereafter drug release rate became slow gradually and about $90\%$ drug released at day 21. The in vitro release rate determined by dialysis bag method had a good correlation with the in vivo release rate. Huperzine A aqueous solution was intramuscularly injected (i.m.) at 0.4mg/kg and microspheres were intra­muscularly injected at 8.4 mg eq huperzine A/kg in rats. The maxium plasma concentration $(C_{max})$ after i.m. microspheres was only $32\%$ of that after i.m. solution. Drug in plasma could be detectd until day 14 and about $5\%$ of administered dose was residued at the injection site at day 14. The relative bioavailability of huperzine A microspheres over a period of 14 days was $94.7\%$. Inhibition of acyecholinesterase activity (AchE) in rat's cortex, hippocampus and striatum could sustain for about 14 days. In conclusion, huperzine A-loaded microspheres possessed a prolonged and complete drug release with significant inhibition of AchE for 2 weeks in rats.

• 한국환경농학회지
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• 제26권3호
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• pp.228-232
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• 2007

고추작물의 생육기간 중 양분요구특성에 부합하는 새로운 완효성 복합비료를 개발하기 위해 질소 용출율이 110일과 150일로 조절된 완효성 복합비료 110T와 150T을 제조하여 포장 조건에서 질소용출특성을 조사하였다. 그리고 고추에 대한 관행시비량 기준으로 60%의 완효성 복합비료 110T, 150T와 40%의 속효성 비료를 혼합하여 제조한 원예용 완효성 복합비료 CF110과 CF150의 토양 내 질소 용출 특성과 고추의 생육 및 수량에 미치는 영향을 관행처리(NPK)와 비교하여 다음과 같은 결과를 얻었다. 밭 토양조건에서 완효성 질소비료 110T와 150T의 질소 용출율은 시용 8주경과 후 각각 63%, 53%가 용출되어 원예작물인 고추재배에 적용성이 높을 것으로 평가되었다. 원예용 복합비료 CF110과 CF150을 전량 기비로 시용하여 고추를 재배하였다. 고추의 전 생육기간 동안 토양 내 무기태 질소($NH_4^+-N$과 $NO_3^--N$) 함량은 원예용 완효성 복합비료 CF110 처리구에서 NPK 처리구에 비해 높았다. 그러나 CF150 처리구에서 토양 중 무기태 질소 함량은 정식 후 8주까지 NPK 처리구에 비해 낮았다. 원예용 완효성 복합비료 CF110 처리구와 NPK 처리구사이의 고추 생육과 무기성분 함량은 뚜렷한 차이가 없었지만, 수량은 CF110 처리구에서 NPK 처리구에 비해 4% 증수 되었다. 그러나 원예용 완효성 복합비료 CF150 처리구는 NPK 처리구에 비해 수확 후 엽중 질소함량이 낮았으며, 수량도 2% 감소되었다. 따라서 고추재배를 위한 적합한 완효성 복합비료는 CF150 보다는 CF110이었다.

• The Plant Pathology Journal
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• 제23권1호
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• pp.26-30
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• 2007

Phosphorous acid is known to effectively control various Oomycetes diseases. The phosphoric acid moves upward and downward through the xylem and phloem in plants. The sustainable forms of the slow releasing chemical in rhizosphere would be ideal to be up-taken by plants. Therefore, we developed a new system for phosphorous acid formulation using a carrier coated with polysaccharides. When the product was applied in rhizosphere, the adequate amount of phosphorous acid was consistently released up to 4 weeks in rhizosphere soils. While soil drenching with phosphorous acid at 1,000 ${\mu}g/ml$ and metalaxyl at 150 ${\mu}g/ml$ were not effective to control pepper Phytophthora blight for 4 weeks, direct application of our formulation product around basal stem of pepper plants resulted in excellent disease control effect against Phytophthora blight over 4 weeks. The application of 4 g of our product per plant was optimum to control the disease, and 8 g product/plant did not cause phytotoxicity. Based on the results, we conclude that the applications of the formulation product once or twice during cropping season can control Phytophthora diseases on various crops.

• 한국식품영양학회지
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• 제30권3호
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• pp.591-598
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• 2017

To prolong the shelf-life of strawberry, samples were treated with gel packs containing slow-released chlorine dioxide($ClO_2$) gas at 3~7 ppm for 6 days at room temperature. The weight loss and decay ratio as well as changes in pH, color and texture properties of the treated samples were investigated. The weight of the control and $ClO_2$ gas treated samples decreased slightly, but the weight of the control changed faster than those of the $ClO_2$ gas treated samples during the storage period. The decay ratio of control was higher than those of the $ClO_2$ gas treatments since 4 days of storage. The pH and acidity in the control and in the $ClO_2$ gas treated samples were no differences during storage period. The lightness of strawberry decreased during storage, but there was no difference in lightness among the treatments even when storage time was extended. The redness and yellowness of the control showed higher change than those of the $ClO_2$ gas treatments during 6 days. The firmness of the control changed more rapidly than those of the $ClO_2$ gas treatments during 6 days. Especially, the samples treated 3 and 5 ppm $ClO_2$ gas were the least changed. And the scores for appearance, firmness and overall acceptance control and 7 ppm $ClO_2$ gas treatment decreased more rapidly than those of 3 and 5 ppm treatment.

• 한국식품영양학회지
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• 제31권1호
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• pp.127-134
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• 2018

To prolong the shelf-life of chicken breast meat, samples were treated with gel packs containing slow-released chlorine dioxide ($ClO_2$) gas at 7~15 ppm for eight days at $4^{\circ}C$. The microbial, physicochemical properties and sensory evaluation of the treated samples were investigated. The total number of bacteria in the control increased during storage and showed 6.78 log CFU/g on the 8th day of storage, but $ClO_2$ gas treatments showed 6.24~6.58 log CFU/g at the same time. The initial pH of chicken breast meat was 6.00 and gradually increased during storage. And $ClO_2$ gas treatments did not show any significant difference from the control during storage period, but maintained a generally lower pH than that of the control. The lightness, redness, and yellowness during storage were not significantly different between the control and the 7~10 ppm $ClO_2$ gas treatments. However, as the storage period was increased, the redness of 15 ppm $ClO_2$ gas treatment was reduced. The cooking loss and shear force were not different between the control and $ClO_2$ gas treatments during the storage period. Volatile basic nitrogen (VBN) increased in the control from the 6th day of storage and 23.80 mg% in the 8th day of storage. However, VBN of $ClO_2$ treatments showed lower than that of the control. In the change of sensory evaluation during storage, 10 ppm $ClO_2$ treatment showed the highest preference in odor, appearance and overall acceptance during storage period.

• 한국환경농학회지
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• 제42권2호
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• pp.112-120
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• 2023

Methane (CH₄) and nitrous oxide (N₂O) are significant contributors to greenhouse gas (GHG) emissions from rice fields. Mid-summer drainage is a commonly practiced water management technique that reduces CH₄ emissions from rice fields. Slow-release fertilizers gradually release nutrients over an extended period and have been shown to reduce N₂O emissions. However, the combined effect of slow-release fertilizer and water management on GHG emissions remains unclear. This study compared GHG emissions from a rice paddy subjected to mid-summer drainage for 10 days (control) with that of a rice paddy subjected to prolonged mid-summer drainage for 20 days combined with slow-release fertilizer (W+S). Gas sampling was conducted weekly using a closed chamber method. During the rice cultivation period, cumulative CH₄ and N₂O emissions were reduced by 12.3% and 16.2%, respectively, in the W+S treatment compared to the control. Moreover, the W+S treatment exhibited a 1.9% increase in grain yield compared to the control. Under experimental conditions, slow-release fertilizers, in combination with prolonged mid-summer drainage, proved to be the optimal approach for achieving high crop yield while reducing GHG emissions. This represents an effective strategy to mitigate GHG emissions from rice paddy fields.

• 한국토양비료학회지
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• 제45권4호
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• pp.551-554
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• 2012

The present laboratory investigation was conducted to assess the effect of heavy metals on carbon mineralization. Soil was treated with three concentrations (50, 100 and $150{\mu}mol\;g^{-1}$ soil) of two heavy metals (Cd and Zn) in a factorial combination of treatments replicated four times. Determination of carbon mineralization was carried out at 3, 7, 14, 21, 28, 42 and 56 days after metal treatments.. The amount of $CO_2$-C released from heavy metal treated soils was found to be decreased at an increasing rate during the first 28 days, followed by slow release as incubation progressed. The total amounts of $CO_2$-C released were 448, 382 and $348mg\;kg^{-1}$ soil respectively for soils treated with 50, 100 and $150{\mu}mol\;g^{-1}$ soil of Zn. The corresponding figures for Cd treated soils were 406, 354 and $282mg\;kg^{-1}$ soil implying that dose-dependent reduction in cumulative $CO_2$-C released from soils. The inhibition of carbon mineralization was found to be high in Cd treated soils than that of Zn treated. Therefore, tolerance and adaptation of the microbial community is likely to be related to the concentration and the type of metal. According to the results, carbon mineralization can be considered as possible indicator of soil pollution by means of heavy metals.

• 아시안잔디학회지
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• 제18권2호
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• pp.63-70
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• 2004

본 연구는 늘어나는 골프 수요에 대처하고 친환경적인 골프장 그린 관리를 위해 완효성 비료 Methylen Urea(MU)와 미생물 제재 T-Vigor의 사용이 크리핑 벤트그래스 '크렌쇼우'의 생육에 미치는 영향을 조사하고자 하였다. 실험장소는 2004년 4월부터 2004년 8월까지 크리핑 벤트그래스 '그랜쇼' 그린인 렉스필드 골프장의 벨리코스 3, 4, 5번에서 수행되었다. 실험구 처리는 완효성 비료인 메칠렌 우레아(Methylen Urea, MU, 25-10-15)를 $5g/m^2$씩 5회 액상 시비하였고, 미생물 비료(T-Vigor)는 살균한 처리구와 살균하지 않은 원액을 $7.5m\ell/m^2$를 2회, $5.5m\ell/m^2$를 5회 처리하였다. 실험구의 크기는 $1m\times1m$이며 3반복 완전임의 배치하였다. 실험 결과를 요약하면 다음과 같다. 1. 잔디 신초밀도는 Methylen Urea(MU) 처리구가 각 처리구보다 월등히 높았으며 기간이 지남에 따라 처리구별 차이가 감소하는 현상을 보였다. 미생물 비료 T-Vigor 처리구의 잔디 신초밀도는 살균된 처리구와 차이가 적었으나 대조구 보다는 높게 나타났다. 2. 엽록소 함량은 Methylen Urea(MU) 및 T-Vigor 처리구가 다른 처리구보다 높았으며, MU 비료는 비료성분이 급속히 흡수되지 않고 지속적으로 공급되는 것으로 판단된다. 3. 뿌리 길이는 Methylen Urea(MU) 처리구가 대조구에 비해 5cm이상 길게 나타났으며, T-Vigor 처리구보다 길었다. 미생물 비료 T-Vigor처리구의 뿌리 길이는 살균된 처리구보다 3cm이상, 대조구 보다 4cm이상 길었다. 4. 예지물 중량은 Methylen Urea(MU) 처리구가 대조구에 비해 $15\%$정도의 증가하였으며, T-Vigor 처리구 대비에서도 약 $6\%$ 이상 증가하였다. 5. 지상부 및 지하부의 건물중에 있어서도 Methylen Urea(MU) 및 T-Vigor 처리구가 대조구에 비해 무거웠으며, 타 처리구에 비해서도 무거웠다. 본 연구는 사용중인 그린에 완효성 비료 및 미생물 비료의 사용이 크리핑 벤트그래스의 생육에 미치는 영향을 분석하고자 하였다. 그러나 본 연구에서는 MU 및 T-Vigor 사용시 속효성 비료와의 경제성 분석, 고온장해 시 잔디 생육분석 등에 대한 연구가 부족하여 추가적인 연구가 필요할 것으로 판단된다.

• 한국작물학회지
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• 제37권6호
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• pp.499-505
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• 1992

본 시험은 완효성비료를 이용한 전량기비시비방법을 개선하고자 식양토(덕평통)와 사양토(강서통)에서 완효성비료인 조선완효성비료와 Meister 15를 이용하여 시비방법에 따른 완효성비료의 시용효과를 검토한 결과는 다음과 같다. 1. 공시토양별 암모니아태 질소의 용출량은 담수 4일째 사양토에서 95ppm, 식양토에서 60ppm 이었다. 2. 벼 잎색도는 조선완효성비료가 Meister 15보다 낮았고, 시비방법간에는 측조시비구보다 전층시비구에서 높았다. 3. 질소 효율은 Meister 15 > 관행 > 조선완효성비료의 순으로 높았고, 시비방법간에는 차이가 적었다. 4. 단립면적당 경수는 조선완효성비료는 측조시비구가 전층시비구보다 많았고, Meister 15는 전층시비구가 측조시비구보다 많았으며, 간장은 Meister 15 > 관행 > 조선 완효성비료의 순으로 길었고, 시비 방법간에는 전층시비구가 측조시비구보다 길었다. 등숙율은 완효성시비가 관행보다 높았고, 시비방법간에는 전층시비구가 측조시비구보다 낮았다. 5. 수량은 식양토에서 비료간 수량차이가 컸으나, 시비방법간에는 수량차이가 적었고, 사양토에서는 비료간, 시비방법간에 수량차이가 적었다. 6. 이상의 결과에서 Meister 15와 같은 완효성비료는 전층시비법으로 시용하여도 좋을 것으로 판단되었다.