• Title/Summary/Keyword: Slow release

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Effects of Slow-Release Nitrogen Fertilizers, Latex coated urea and Meister 10, on Direct Seeded Rice in Flood Soil (벼 담수직파재배시 완효성질소비료의 시용 효과)

  • Jang, Myung-Hwan;Back, Jun-Ho;Lee, Seung-Ho;Lee, Sang-Jo;Lim, Jun-Young;Kim, Bok-Jin
    • Korean Journal of Soil Science and Fertilizer
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    • v.34 no.6
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    • pp.401-406
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    • 2001
  • This study was conducted to find out the effect of slow-release nitrogen fertilizer, such as latex coated urea(LCU) and Meister10(MS10) on direct seeded rice in flooded soil(FS). Junghwabyeo, and early maturity rice cultivar grown on the plots which were treated with None-nitrogen, urea, LCU and MS10 plot. Growth characteristic, yield and yield components were investigated. Nitrogen uptake-efficiency and physico-chemical properties of soil before-after experiment were analyzed. Plant height and number of tillers $m^{-2}$ in LCU and MS10 plot at early grow stages were higher than those of Urea plot. MS10 and LCU plot showed similar tendency on the plant height but MS10 plot was higher than LCU plot on the number of tillers $m^{-2}$. The number of seedling $m^{-2}$ were no significant differences among None-N, urea, and MS10 plot. Heading date and leaf color were no significant differences among None-N, urea, and MS10 plot. Culm length in LCU and Ms10 plot were longer compared with urea plot, but panicle length were similar among with Urea, LCU and MS10 plot. Number of panicles $m^{-2}$ was highest in MS10 plot and it was similar between LCU and Urea plot. Yield were greater in order of Ms10 > LCU > Urea plot. Nitrogen uptake and nitrogen efficiency were greater in order of MS10 > LCU > urea plot. After the experiment, total content of nitrogen in soil was not changed at all treatments, but pH, P and K of soil were lower than that of before experiment at all treatments.

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Effects of slow release gonadotropin releasing hormone analog on milt characteristics and plasma levels of gonadal steroids in greenback flounder, Rhombosolea tapirina

  • Lim, Han-Kyu
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2003.05a
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    • pp.187-188
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    • 2003
  • Conadotropin releasing hormono analogs (GnRHa) have now been tested successfully a range of marine and freshwater species and been shown to be an effective strategy for improving milt quantity and quality (Mylonas and Zohar, 2001; Zohar and Mylonas, 2001; Lim et at, , 2002). Greenback flounder (Rhombosolea tapirina) is currently under consideration as a potential culture species in south-eastern Australia. (omitted)

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The Characteristric of Oxygen Consumption of Contaminated river-bed Sediment (오탁하천 하상저니의 산소 소비특성에 관한 연구)

  • Han, Jong-Ok
    • 수도
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    • s.50
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    • pp.20-25
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    • 1989
  • Water quality of river is greatly influenced by sediments of planktons, suspended solids and organic matters being transported by efflenced. The water quality is also affected by their release at the place of sediments with slow flow of water. This paper deals with the Characteristics of Oxygen consumption of sediments in small river which is greatly vary with time. Some typical samples of sediment were taken from both aerobic and anaerobic condition reserved for several months. and, the samples of sediment were checked on the relative ratio of oxygen consumption by nitrification.

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SAFETY ANALYSIS METHODOLOGY FOR AGED CANDU® 6 NUCLEAR REACTORS

  • Hartmann, Wolfgang;Jung, Jong Yeob
    • Nuclear Engineering and Technology
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    • v.45 no.5
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    • pp.581-588
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    • 2013
  • This paper deals with the Safety Analysis for $CANDU^{(R)}$ 6 nuclear reactors as affected by main Heat Transport System (HTS) aging. Operational and aging related changes of the HTS throughout its lifetime may lead to restrictions in certain safety system settings and hence some restriction in performance under certain conditions. A step in confirming safe reactor operation is the tracking of relevant data and their corresponding interpretation by the use of appropriate thermal-hydraulic analytic models. Safety analyses ranging from the assessment of safety limits associated with the prevention of intermittent fuel sheath dryout for a slow Loss of Regulation (LOR) analysis and fission gas release after a fuel failure are summarized. Specifically for fission gas release, the thermal-hydraulic analysis for a fresh core and an 11 Effective Full Power Years (EFPY) aged core was summarized, leading to the most severe stagnation break sizes for the inlet feeder break and the channel failure time. Associated coolant conditions provide the input data for fuel analyses. Based on the thermal-hydraulic data, the fission product inventory under normal operating conditions may be calculated for both fresh and aged cores, and the fission gas release may be evaluated during the transient. This analysis plays a major role in determining possible radiation doses to the public after postulated accidents have occurred.

Injectable Gel Type Formulation of Hydrated Egg Phosphatidylcholine and Hyaluronate for Local Drug Delivery

  • Kim, Sang-Gyun;Chung, Hesson;Lee, In-Hyun;Kang, Seung-Back;Kwon, Ick-Chan;Sung, Ha-Chin;Jeong, Seo-Young
    • Journal of Pharmaceutical Investigation
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    • v.32 no.3
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    • pp.165-172
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    • 2002
  • Injectable gel composed of egg phosphatidylcholine (egg PC), hyaluronate (HA) and water was formulated for local drug delivery. The lamellar liquid crystalline structure of the egg PC/water system did not change by adding HA in the formulation. However, egg PC/HA/water gel was more resistant to erosion than the egg PC/water gel. The egg PC/HA/water and egg PC/water gels containing model drugs, tetracycline and sudan IV were prepared to perform in vitro and in vivo drug release experiments. In vitro release of tetracycline was sustained in the gel type formulations. The release rate of hydrophobic sudan IV was extremely slow. More than 99% of sudan IV remained inside the gel after 5 days. In vivo release of drugs from the air pouch model in Balb/c mice shows that lipophilic sudan IV remained for more than 10 days whereas tetracycline remained for 1 day in the pouch. The compatibility of the gels was also examined by histopathology. The gels did not cause any adverse inflammatory effect in the air pouch.

The Influence of Traffic Time and Fertilizer Type on the Quality of Golf Course Putting Greens (답압시간과 비료종류가 골프코스 그린 잔디의 품질에 미치는 영향)

  • Lee, Sung-Woo;Lee, Jae-Pil;Kim, Doo-Hwan
    • Asian Journal of Turfgrass Science
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    • v.22 no.1
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    • pp.65-74
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    • 2008
  • Traffic management is becoming an important issue in turfgrass practise on golf course. The objective of this study was to investigate the combined impact of different traffic times and types of fertilization. Traffic treatment was applied in morning (AM), noon, and afternoon (PM). Fertilizers used include faster-release fertilizer (21-17-17) and slow-release fertilizers (12-6-18, 11-3-22, 20-3-20, 10-3-10). Experiment was conducted from Oct. 1 to Nov. 30, 2005 on a nursery putting green of Incheon Grand Golf Club. The growth and quality of creeping bentgrass (Agrostis polustris cv. 'Seaside II') were evaluated on visual leaf color, leaf texture, shoot density, and root length. The measurement at 20 days after treatment, turfgrass color and leaf texture showed the best result on 10-15-10 + Noon-traffic plot. Turf quality and traffic tolerance were not different at Am and Pm traffic treatment. However, traffic stress in early morning and late evening caused the most severe damage to the turfgrass. Shoot density was the highest in 10-15-10 + Noon-traffic treatment but root length was not different among treatments after 30 day measurement. Among the fertilizers, slow release fertilizer resulted in higher turf quality and traffic tolerance than fast release fertilizer, however, shoot density did not showed a significantly different. For the fast recuperation of turfgrass from traffic injury in the early winter, it is recommended to avoid early morning and late evening traffic such as cup replacement and other maintenance practise. It is also recommended to delay the first tee-up time and ending early for last tee time during cold weather season.

Growth Response of Hot Pepper Applicated with Ammonium (${NH_4}^+$) and Potassium ($K^+$)-Loaded Zeolite (암모늄이온 (${NH_4}^+$)과 칼륨이온 ($K^+$)이 흡착된 천연 Zeolite 처리가 고추의 생육에 미치는 효과)

  • Li, Jun-Xi;Wee, Chi-Do;Sohn, Bo-Kyoon
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.5
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    • pp.741-747
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    • 2010
  • The feasibility of using ammonium (${NH_4}^+$) and potassium ($K^+$)-loaded zeolite (NK-Z) as a slow-release fertilizer to control nitrogen and potassium supply was investigated in this study. The growth responses, which were determined in terms of shoot length, shoot fresh weight, and fresh fruit weight, were greater in plants treated with NK-Z than in those treated with chemical fertilizers (CF) after 18 weeks of transplantation. The total fruit weight per plant in treated with NK-Z as the basal and additional fertilizer (ZBAF) was 14.89% higher than that of CF. The nitrogen and potassium contents in NK-Z amended soils were higher than those in CF amended soils in the final stage of plant growth. The ammonium nitrogen ($NH_4$-N) concentration in ZBAF amended soils was 63.41% higher than that in CF amended soils.