• Title/Summary/Keyword: 저온 장해

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LNG선 manifold platform 재질에 대한 고찰

  • 김봉옥;장해주;김점수
    • Bulletin of the Society of Naval Architects of Korea
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    • v.31 no.2
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    • pp.40-42
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    • 1994
  • LNG의 선적 및 하역용으로 양현 중앙부에 각각 설치되는 LNG의 MANIFOLD 구조에 있어 LNG의 선적 또는 양하시 Manifold Deck 상에 있는 연결관내의 LNG가 밸브를 통해 누설되어 코밍(coaming)내에서 자영증발 되는 동안, 누설된 저온 LNG가 Deck부재에 큰 영향을 미치게 된다. 따라서 누설된 LNG의 최대 증발시간 및 Manifold Platform 각 부분에 미치는 온도, 영향 등을 종합적으로 검토하여 부재재질의 효과적인 선정을 기해야 항 것이다. 여기서는 당사가 국내 최초로 건조한 바 있는 Single Loading System LNG선의 Manifold platform에 있어 현업 실적용을 중심으로 고찰해 보고자 한다.

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Improvement of Tomato Seedling Quality under Low Temperature by Application of Silicate Fertilizer (저온 저장 시 규산 처리에 의한 토마토 묘소질 향상)

  • Vu, Ngoc-Thang;Tran, Anh-Tuan;Le, Thi-Tuyet-Cham;Na, Jong-Kuk;Kim, Si-Hong;Park, Jong-Man;Jang, Dong-Cheol;Kim, Il-Seop
    • Journal of Bio-Environment Control
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    • v.26 no.3
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    • pp.158-166
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    • 2017
  • The object of this study was to improve tomato seedling quality in low temperature(below 7, $10^{\circ}C$ during night time or daily mean air temperature was $18^{\circ}C$) by application of silicate fertilizer. Six different silicate fertilizer concentrations (8, 16, 32, 64, 128, and 256mM) or water as the control were applied to tomato seedlings twice a week for 20 days. Positive effects were observed in the growth parameters of the seedlings treated with 16 and 32mM silicate fertilizer; the most effective concentration of silicate at which seedlings showed the best performance was 16mM. However, a high concentration of silicate (256mM) caused negative effects on the growth. The transpiration rate decreased alongside with the increase of silicate concentration up to 32mM, possibly due to the increased stomatal diffusive resistance. Silicate stimulated the growth and development of tomato seedlings, resulting in increased growth parameters and root morphology. However, no significant differences were observed among treatment numbers of soil-drenching wuth the silicate (6, 10, or 20 times with 16mM) for 20 days, suggesting that silicate treatment with 6 times may be sufficient to induce the silicate effects. The application of 16mM of silicate fertilizer reduced relative ion leakage and chilling injury during low temperature storage. In addition, the seedlings treated with silicate fertilizer recovered faster than those without silicate treatment after low temperature storage.

Influence of chilling stress seeding stages on photosynthetic rate and physiological reponses of cucumber(Cucumis sativus L.) (오이묘에 냉온 Stress가 광합성 및 생리반응에 미치는 영향)

  • Nam, Yooun-Il;Woo, Young-Hoe;Chum, Hee;Kim, Hyung-Jun
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 2001.11a
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    • pp.163-171
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    • 2001
  • 시설 원예작물의 겨울철 온도환경 관리에 대한 연구는 난방비 절약을 위한 저온관리 한계온도 구명(Tanaka 등, 1986), 또는 근권부 온도 조절에 의한 작물의 생산성 증진 연구와 같은 실용적 측면의 연구가 많이 수행된 바 있다(Fujie와 Saidou, 1983). 그러나 시설의 온풍기 고장 또는 정전 등으로 작물이 생육한계 온도이하의 저온상태에서 장시간 경과 되었을 때 나타나는 여러가지의 생리적인 장해나 피해에 대한 연구는 매우 적은 실정이다(Reyes와 Jennings, 1994). (중략)

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Effect of survival rate of chilled cucumber (Cucumis sativus L.) seedlings as influenced by light exposure and chilling started at different time of day. (냉온처리 전후의 광환경 조건이 오이 묘의 생존율에 미치는 영향)

  • Nam, Yooun-Il;Woo, Young-Hoe;Chum, Hee;Kim, Hyung-Jun
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 2001.11a
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    • pp.156-162
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    • 2001
  • 최근 겨울동안에 폭설과 강풍과 같은 기상이변이 잦아지면서 기상재해와 함께 정전에 의한 시설 원예작물의 저온피해도 빈번하게 발생하고 있으나, 실제적으로는 어느 정도의 피해가 있는지 파악되지 못하고 있으며 피해 예측에 관한 정보도 축적되어 있지 못한 실정으로 이에 관련된 연구가 요구되고있다. 시설 재배시 겨울철 온도환경 관리에 대한 연구는 주로 난방비 절약을 위한 저온관리 한계온도 구명(Tanaka 등, 1986), 또는 근권부 온도 조절에 의한 작물의 생산성 증진 연구와 같은 실용적 측면의 연구(Lee, 1994; Fujie와 Saidou, 1983) 및 저온 장해의 생리기작(Herner, 1990; Patterson 등, 1976; Reyes와 Jennings, 1994; Wolk와 Herner, 1982; Wright and Simon, 1973)에 관련된 연구가 수행되고 있으며 냉온 피해를 받을 당시의 전후환경조건과 산화작용에 관련된 연구는 토마토(Kerdnaimongkol 등, 1997) 등 몇 개 작물(King 등 1982)에서 보고된바 있다.(중략)

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Physio-chemical studies on the seed-browning in mature green peppers stored at low-temperature (Part 2) -Changes in enzymatic activity with the seed-browning effect- (녹숙(綠熟)고추의 저온저장(低溫貯藏)에 따른 종자갈변(種子褐變)에 관(關)한 생리화학적연구(生理化學的硏究) -제 2 보(第 2 報) 종자갈변(種子褐變)에 따른 효소활성(酵素活性)의 변화(變化)-)

  • Lee, Sung-Woo
    • Korean Journal of Food Science and Technology
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    • v.3 no.1
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    • pp.37-43
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    • 1971
  • (1) Relatively active polyphenol oxidase influence was seen at $0{\circ}C$, and the optimal pH level for the enzyme from the seeds of a small type sweet pepper Zairaisisi is 6.5. (2) The starting stage of the brown coloration with low-temperature injuries showed a strong activity of polyphenol oxidase, and the activity drops to 0 as the entire seed became brownish. (3) The browning effect with enzyme solution of polyphenol extracts suggested that the brown coloration continues in vitro even if polyphenol oxidase activity is nil. (4) Although cytochrome oxidase activity dropped when an abnormality occurrs in electron pathways of respiration at the starting stage of the browning with low temperature injuries, there was no marked influence of it on the total respiration, indicating the fact that polyphenol oxidase can take place of terminal oxidase in the compensatory respiration process.

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Changes in Quality Parameters of Tomatoes Harvested at Different Mature Stages during Storage (수확시의 숙도에 따른 저온저장 중 토마토의 품질인자의 변화)

  • Choi, Jeong Hee;Jeong, Moon Cheol;Kim, Dongman
    • Food Science and Preservation
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    • v.20 no.2
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    • pp.151-157
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    • 2013
  • This study was conducted to investigate the effect of mature stages on quality of Rafito tomatoes (Lycopersicon esculentum Mill.) during storage at low temperature. Tomatoes grown in greenhouse were harvested at three different mature stages (turning, pink, and red), packaged with a 30-${\mu}m$-thick polyethylene film, and then stored at 5 and $10^{\circ}C$, respectively. The changes in firmness, soluble solids content (SSC), titratable acidity (TA), colour, lycopene content, decay, and chilling injury were measured on a weekly basis. After three weeks of storage, chilling injury and decay were found to have individually occurred at 5 and $10^{\circ}C$, respectively. As there was little change in quality at $5^{\circ}C$, it was concluded that red tomatoes could maintain their good quality for two weeks. The normal postharvest ripening was inhibited in the turning and pink tomatoes during storage at $5^{\circ}C$. The turning and pink tomatoes showed improved quality after two-week storage at $10^{\circ}C$. In particular, the turning fruits showed the highest firmness throughout the storage period. Furthermore, the red colour, SSC/TA, and lycopene content of the turning fruits reached the same levels as with the red fruits after two-week storage at $10^{\circ}C$. These results suggest that red tomatoes should be stored at $5^{\circ}C$ to inhibit decay, and that the optimum temperature for early-harvested tomato (turning and pink) is $10^{\circ}C$ for the ripening process after harvest.

Studies on the Varietal Differences of Tolerance to Cold Damage in Seedling Stage of the Rice Plant (수도 유묘기 내냉성의 품종간 차이에 관한 연구)

  • Chung-Ik Cho;Seong Kuk Bae
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.21 no.1
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    • pp.35-42
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    • 1976
  • In Korea, two types of rice varieties are being cultivated widely, Japonica and Japonica-Indica cross. Generally speaking, the latter shows weak cold tolerance than the former and so brought about many problems in cultural practices. This study was conducted to investigate the effect . of various temperature conditions on rice seedlings growth, especially the contents of chlorophyll and the percentage of nitrogen. And the result obtained indicated the varieties of Japonica-Indica intend to weak cold tolerance than Japonica varieties.

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Development of Prototype Automatic Grafting System for Fruit-bearing Vegetables (박과 채소용 자동접목 시작기 개발)

  • H. Hwang;Kim, S.C.;K.D. Ko
    • Journal of Biosystems Engineering
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    • v.24 no.3
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    • pp.217-224
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    • 1999
  • 우리나라의 경우 각종 장해와 주년 수요의 증가에 따른 불시재배의 증가로 인하여 저온신장성, 병해저항성 등과 같이 작물의 내성증진을 목적으로 접목묘의 이용이 급속도로 신장되고 있다. 특시 연작장해가 심한 박과형 채소류는 대부분 접목재배가 필요한 실정이다. 그러나 국내의 경우, 접목작업은 거의 수작업으로 행해지며 세밀한 조작과 숙련성 그리고 많은 노력을 필요로 한다. 따라서, 접목 생산성을 높일 수 있는 저가의 자동화 시스템 개발이 요구된다. 다양한 접목법들 중 현재 농가에서 가장 광범위하게 이용되고 있는 호접은 삽접 및 절단접에 비하여 자동화가 어렵고 활착 후 절단작업이 부가적으로 필요하나 접목 후 순화공정이 간단하고 활착률이 높다. 본 논문에서는 호접과 삽접에 대하여 접목 후의 활착률 및 접목에 소요되는 작업시간을 비교하였고, 호접법에 의거하여 작업공정을 생력화한 육묘 자동접목 시작기를 개발하였다. 시작기는 농가조합 및 중규모 육묘장의 설비를 지향하여, 묘판 및 접목묘의 취급을 제외하고 1인 접목작업 형태의 자동화 시스템으로 개발하였다. 시작기는 크게 버퍼기능을 부착한 배치형 육묘장치부, 2세트에 공압 매니퓰레이터, 대목과 접수의 원할한 접목을 위해 설계한 특수 그리퍼, 각고 조절형 절단부, 진동형 클립공급부 그리고 자동 클립 장착장치로 구성하였다. 접목 작업시간은 대략 4ch 정도이나 작업시간의 조정이 가능하도록 하였다. 실험실에서 수행한 간이접목 시험 결과, 절단날이 대목과 접수의 접촉부위를 관통할 때 접촉면이 서로 어긋나는 경우가 발생하였으나 육묘들이 호접에 적정한 기하학적 물성 요건을 갖춘다면 80% 이상의 접목 육묘의 기하학적 물성에 따른 체계적인 접목시험이 필요하다.

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Effects of Soil Moisture and Chemical Application on Low Temperature Stress of Cucumber (Cucumis sativus L.) Seedling (토양수분조건 및 화학물질처리가 오이묘의 저온장해에 미치는 영향)

  • Nam, Yooun-Il;Woo, Young-Hoe;Lee, Kwan-Ho
    • Journal of Bio-Environment Control
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    • v.15 no.4
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    • pp.377-384
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    • 2006
  • This study was conducted to investigate the effects of chemical application and amout of soil moisture on low temperature stress of cucumber seedling under the greenhouse conditions. When chilling treatments ($2^{\circ}C$) were begun at 07:00AM, survival rates of seedlings of two conditions; -0.3 bar and -5.5 bar were 28.3% and 83.3% respectively. But when chilling treatments were begun at 6:00PM - even the soil moisture condition was -0.3 bar - the survival rate was above the 87%. When reducing the soil moisture from -0.3 bar to -9.0 bar, ABA content in leaf was inc.eased by 6.5fo1d. Spraying of abscisc acid (ABA) before or after the chilling significantly increased the survival rates of seedlings, decreased the amounts of leaking electrolytes and prevented the yield reductions. ABA application on the soil before the chilling appeared to be more effective than the application after the chilling with foliar spray. Spraying of ABA ($10^{-5}M$), urea (0.2%) or $KH_2PO_4$ was effective in counteracting the low temperature, which causes growth deterioration and yield reduction in cucumbers.