• 제목/요약/키워드: low temperature growth

검색결과 2,033건 처리시간 0.044초

저온에 의한 수도의 Discoloration 발생에 관한 연구-온도에 의한 가용성단백질구성 변화에 관하여- (Studies on the leaf discoloration caused by low temperature-Change of soluble protein components by temperature -)

  • 박경배;전중효행;원전이랑
    • 한국작물학회지
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    • 제23권1호
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    • pp.1-4
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    • 1978
  • 단백질구성 변화를 여러가지 온도조건에서 Japonica형인 진흥, Indica$\times$Japonica교잡품종인 통일, 밀양 2003, 영남조생, 유신등을 공시하여 'Growth Cabinet'를 사용하여 검토 하였던바 다음과 같은 결과를 얻었다. 1. 저온하에서 엽록소함양감소는 Japonica형 품종보다 Indica형 품종에서 심하였다. 2. 단백질구성비(저분자가용성단백질에 대한 고분자가용성단백질의 비)는 고온하에서 높았고, 저온하에서 낮았다. 3. 품종간 단백질구성비는 저온하에서 Japonica형 품종보다 Indica형 품종이 낮았다. 4. 엽신의 엽록소함양과 가용성단백질구성비와는 정의 유의 상관관계가 인정되었다.관계가 인정되었다.

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해양구조용강의 피로강도향상 공법개발 (The Development Methods of Fatigue Strength Improvement for the Marine Structural Steel)

  • 박경동;정재욱
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2003년도 추계학술대회 논문집
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    • pp.106-111
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    • 2003
  • This study made an experiment On fatigue crack propagation da/dn, stress intensity factor range ${\Delta}K$ respectively in room temperature and in low temperature. And we got the following characteristics from fatigue crack growth test carried Out in the environment of room temperature and law temperature at $25^{\circ}C$, $-60^{\circ}C$, $-80^{\circ}C$, and $-100^{\circ}C$ in the range of stress ratio of 0.3 by means of opening made displacement. The threshold stress intensity factor range ${\Delta}Kth$ in the early stage of fatigue crack growth (Mode I) and stress intensity factor range ${\Delta}K$ in the stable of fatigue crack growth (Made II) was decreased in proportion to descend temperature. It assumed that the fatigue resistance characteristics and fracture strength at law temperature and high temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region.

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저온 GaN의 성장 온도에 따른 에피택셜 GaN의 stress relaxation 효과 (Effect of low-temperature GaN grown at different temperature on residual stress of epitaxial GaN)

  • 이승훈;이주형;오누리;이성철;박형빈;신란희;박재화
    • 한국결정성장학회지
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    • 제32권3호
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    • pp.83-88
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    • 2022
  • 이종 기판과 GaN의 물성 차이로 인해 발생하는 결함을 제어하기 위한 다양한 방법 중 동종 물질을 완충층으로 사용하는 LT-GaN 방법을 사용하여 완충층과 성장 온도의 상관성을 자체 제작한 성장 장비를 통해 확인하고자 하였다. 성장 온도에 따라 표면에 형성된 LT-GaN 결정성에 변화가 있었으며, annealing 후 LT-GaN가 나타내는 결정성에 따라 epiGaN의 응력 완화 효과에 차이점이 있었다. 반면 LT-GaN의 높은 결정성은 다결정을 형성하는 원인으로 작용하여 그 위에 성장하는 epi-GaN의 결정질을 저해하는 결과를 유발하였다.

식물생장용 저압챔버 내의 기온, 상대습도 및 압력의 변화 (Variations of Air Temperature, Relative Humidity and Pressure in a Low Pressure Chamber for Plant Growth)

  • 박종현;김용현
    • 생물환경조절학회지
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    • 제18권3호
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    • pp.200-207
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    • 2009
  • This study was conducted to analyze the variations of air temperature, relative humidity and pressure in a low pressure chamber for plant growth. The low pressure chamber was composed of an acrylic cylinder, a stainless plate, a mass flow controller, an elastomer pressure controller, a read-out-box, a vacuum pump, and sensors of air temperature, relative humidity, and pressure. The pressure leakage in the low pressure chamber was greatly affected by the material and connection method of tubes. The leakage rate in the low pressure chamber with the welding of the stainless tubes and a plate decreased by $0.21kPa{\cdot}h^{-1}$, whereas the leakage in the low pressure chamber with teflon tube and rubber O-ring was given by $1.03kPa{\cdot}h^{-1}$. Pressure in the low pressure chamber was sensitively fluctuated by the air temperature inside the chamber. An elastomer pressure controller was installed to keep the pressure in the low pressure chamber at a setting value. However, inside relative humidity at dark period increased to saturation level.. Two levels (25 and 50kPa) of pressure and two levels (500 and 1,000sccm) of mass flow rate were provided to investigate the effect of low pressure and mass flow rate on relative humidity inside the chamber. It was concluded that low setting value of pressure and high mass flow rate of mixed gas were the effective methods to control the pressure and to suppress the excessive rise of relative humidity inside the chamber.

고압 수증기 내에서 산화막 형성에 관한 연구 (Oxide Layer Growth in High-Pressure Steam Oxidation)

  • 박경희;안순의;구경완;왕진석
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
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    • pp.735-738
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    • 2000
  • This paper shows experimentally that oxide layer on the p-type Si-substrate can grow at low temperature(500$^{\circ}C$∼600$^{\circ}C$) using high pressure water vapor system. As the result of experiment, oxide layer growth rate is about 0.19${\AA}$/min at 500$^{\circ}C$, 0.43${\AA}$/min at 550$^{\circ}C$, 1.2${\AA}$/min at 600$^{\circ}C$ respectively. So, we know oxide layer growth follows reaction-controlled mechanism in given temperature range. Consequently, granting that oxide layer growth rate increases linearly to temperature over 600$^{\circ}C$, we can expect oxide growth rate is 5.2${\AA}$/min at 1000$^{\circ}C$. High pressure oxidation of silicon is particularly attractive for the thick oxidation of power MOSFET, because thermal oxide layers can grow at relatively low temperature in run times comparable to typical high-temperature, 1 atm conditions. For higher-temperature, high-pressure oxidation, the oxidation time is reduced significantly

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Ti-6Al-4V의 피로균열성장거동에 관한 연구(I) (A Study on the Fatigue Crack Growth Behavior in Ti-6Al-4V Alloy(I))

  • 우흥식;한지원
    • 한국안전학회지
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    • 제16권4호
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    • pp.52-57
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    • 2001
  • Fatigue crack growth behaviour of Ti-6A-4V alloy is investigated in air and salt solution environment at room temperature and $200^{\circ}C$. Fatigue crack growth rate is blown to be fast for the formation of corrosive product in hot salt environment. For the effect on corrosion fatigue crack growth behaviour of region II. fatigue crack growth rate in atmosphere had a little gap to both case, $200^{\circ}C$ and room temperature. However, it showed very fast tendency in salt corrosive atmosphere, and it was remarkably accelerated in $200^{\circ}C$ temperature salt environment. When $\Delta$K was approximately 30MPa(equation omitted), fatigue crack growth rate had a little difference between at room temperature and at $200^{\circ}C$ high temperature, however in case of salt corrosive environment the room temperature was 3.5 times Inter and $200^{\circ}C$ high temperature for 16 times than air environment respectively.

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Effect of Temperature Associated with Early Growth Stimulus on Shortening of Heading Dates in Rice

  • Song, Moon-Tae;Lee, Jeom-Ho;Cho, Youn-Sang;Hwang, Hung-Goo
    • Plant Resources
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    • 제5권2호
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    • pp.155-160
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    • 2002
  • The heading date is known to be controlled by two kinds of genetic constituent, photosensitivity and basic vegetable phase. For the latter, the effect of temperature in early growth period is critical to determine the shortness of vegetative growth periods in plant's life. A phytotron experiment on 55 rice cultivars, consisting of two ecotypes of rices, indica and japonica, was conducted at high and low temperature treatments at early growth stage to investigate the possible role of plant growth stimulus by high temperature to associate with shortening of heading date. The high temperature during the early growth stage stimulated the rice growth as measured by plant height with much difference of the growth response between indica and japonica. The conclusive finding that these growth stimulus in early growth stage was highly correlated with the acceleration of heading is, more or less, correlated with the heading of the late growth stage although we could not conclude the genes for early plant growth stimulus by high temperature is the same genes as the genes for accelerating of heading in the late growth stage of plants.

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이상저온 조건이 고추의 생육 및 수량에 미치는 영향 (The Influence of Abnormally Low Temperatures on Growth and Yield of Hot Pepper(Capsicum Annum L.))

  • 박은지;허유;손병구;최영환;이용재;박영훈;서정민;조재환;홍창오;이상규;강점순
    • 한국환경과학회지
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    • 제23권5호
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    • pp.781-786
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    • 2014
  • Growth and physiological disorders caused by abnormally low temperatures were evaluated in pepper, an important field crop in Korea. In addition, the effects of chemical treatment using glutamine was verified on minimizing the damages by low temperature. The growth of pepper plants in stem length and diameter was suppressed as the temperature decreased from $25^{\circ}C$, and the suppression level was the highest for plants grown for 90 days at $20^{\circ}C$. However, root growth was not affected by the different temperatures. The number of leaf and leaf area decreased at the temperatures below $25^{\circ}C$, an optimum temperature for growth. Fresh weight and dry weight decreased for plants grown at $20^{\circ}C$. Pepper fruit yield also decreased by 11% at $20^{\circ}C$ in comparison to $25^{\circ}C$. Falling blossom rate was different depending on the growth temperature, and the rate was 27.2% at $25^{\circ}C$, 35.2% at $22.5^{\circ}C$, and 41.0% at $20^{\circ}C$, indicating that falling blossom rate increased as temperature decreased. Different growth temperatures did not affected on the level of symptom of calcium deficiency and Phytopathora blight. Falling blossom was severe at abnormally low temperature of $20^{\circ}C$, but the treatment of glutamine reduced falling blossom rate and increased the yield by 7.0% as compared to control. The optimum concentration of glutamine treatment was 10 mg/L for yields.

고활성 근권생육촉진균주 Burkholderia pyrrocinia 13-1에 의한 저온조건에서의 유채생육촉진 (Canola Plant Growth Promotion by a Selected Plant Growth Promoting-Rhizobacteria, Burkholderia pyrrocinia Strain 13-1 in the Cold Condition)

  • 이재은;조상민;조영은;박경석
    • 농약과학회지
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    • 제13권4호
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    • pp.262-266
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    • 2009
  • 유채 근권으로 부터 분리된 고활성 근권균 Burkholderia pyrrocinia 13-1는 유채의 생육을 촉진 시키며 특히 저온조건에서의 식물 생육이 우수하다. 이 균주의 유채 처리는 저온조건에서 뿌리의 발근을 좋게 하며 지상부 생육도 다른 대조 균주처리 보다 우수하다. 근권미생물이 가지는 유용 기능 중 식물의 영양 흡수와 병 저항성에 관여하는 시드로포어의 생성, 항균활성과 토양 중 불용화 인산인 칼슘포스페이트를 가용화시켜 식물의 흡수를 돕는 용해 능력이 우수하였다. 이와 같은 특성은 식물의 생육을 촉진시키는 근권세균의 활성기작으로 식물생육 촉진용으로 유채재배에 적용할 수 있을 것으로 기대된다.

Antifreeze proteins promote the germination of low temperature-treated petunia seeds via regulation of antioxidant- and proline-related genes

  • Pe, Phyo Phyo Win;Kyua, Swum Yi;Naing, Aung Htay;Park, Kyeung Il;Chung, Mi-Young;Kim, Chang Kil
    • Journal of Plant Biotechnology
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    • 제47권3호
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    • pp.203-208
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    • 2020
  • The involvement of antifreeze proteins (AFPs; type I and III) in the germination of low temperature-treated petunia seeds (cv. 'Mirage Rose') was investigated. The addition of AFPs (300 or 500 ㎍/l) in low-temperature treatment significantly promoted the germination of seeds compared with that in which AFPs were not added. Among all treatments, treatment with AFP I added at 300 ㎍/l showed the highest germination percentage and improved plant growth. The expression levels of antioxidant-related genes such as superoxide dismutase, peroxidase, and proline synthesis were associated with the germination of low temperature-treated seeds. Overall, this study demonstrated that AFP I may potentially function as a cold-protective agent for the germination of low temperature-treated seeds.