• 제목/요약/키워드: different temperatures

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한국산 자라, Trionyx sinensis (1862)의 자연산란둥지에서 수거한 난들의 항온인공부화에 의해 출생한 새끼자라들의 성비 (Sex Ratios of Juveniles Hatched by Constant Temperatures Artificial Incubation From Eggs Collected in the Natural Nest of Soft-Shelled Turtle, Trionyx sinensis Strauch (1862))

  • 김성한
    • 수산해양교육연구
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    • 제29권3호
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    • pp.702-710
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    • 2017
  • Recently, in many reptiles (14 genera of turtles in five families), common characteristics of incubation temperatures are known to determine the sexes of hatchlings in many species of turtles, including the map turtles, painted turtles and snapping turtles, emys turtle, etc. According to many researcher's reports, in general, incubation at $25^{\circ}C$ (cooler temperatures) produces all or mostly males, however, incubation at $31^{\circ}C$ (higher temperatures) or higher produces all or mostly females. Exceptionally, even cooler temperature ($20^{\circ}C$) produce females, they produced all or mostly females. Accordingly, it is well-known that incubation temperature is the sex determining agent in these turtles. However, this paper presents study of the sex ratio and nest ecology in natural spawning nest: Observations on hatching sex ratios of eggs collected from natural nests of T. sinensis are similar to a previous report of the same genus Trionyx in the soft-shelled turtles. However, this genus (or species) showed some different phenomena to other kinds of turtles such as various kinds turtles mentioned above. After collection of naturally spawned eggs (17 eggs of T. sisnensis) on the natural nests, a laboratory experiment by the constant incubation temperatures was conducted with natural fluctuating soil temperatures in the natural nest with the soft-shelled turtle, T. sinensis. And also laboratory experiments were conducted using constant incubation temperatures of $25^{\circ}C$ (cooler temp.) and $30^{\circ}C$ (higher temp.) with the turtle, T. sinensis. Exceptionally, it was confirmed that the first and second incubation temperatures can't control sex-determination in the freshwater soft-shelled turtle, T. sinensis. The sex ratio approximated 1:1 (${\chi}^2=0.06$, P>0.05 (the Ist experiment). And the sex ratio approximated 1:1 independently of incubation temperature (${\chi}^2=0.33$, P>0.05 (the 2nd experiment). Consequently, temperature has no effect on sex determination in the genus Trionyx in a soft-shelled turtle.

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.

Changes of physiochemical properties of LOX-3 null rice lines stored at different storage temperatures and periods

  • Shin, Woon-Chul;Kim, Jeong-Ju;Park, Hyun-Su;Jeong, Jong-Min;Baek, Man-Kee;Nam, Jeong-Kwon;Park, Seul-Gi;Kim, Choon-Song;Cho, Young-Chan;Kim, Bo-Kyeong
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.69-69
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    • 2017
  • Due to the lack in storage facility, considerable amount of rice is stocked in the open air, which causes increased stale flavor and deteriorates palatability and merchantable quality. Lipoxygenase-3(LOX-3) is involved in the production of volatile constituents in stored rice, and the development of stale flavor is delayed in LOX-3 null rice. LOX activity in the rice grain is localized in bran fraction and the tropical Japonica cultivar 'Dawdam' was reported that the absence of LOX-3 is inherited as a simple recessive trait. Also, it was reported that the peroxidation of unsaturated fatty acids occurs at lower levels in the 'Dawdam' bran fraction during storage than in rice varieties with LOX-3. This study was conducted to develop LOX-3 null rice lines using 'Dawdam' and investigate changes of physicochemical properties of the lines stored at different storage temperatures and periods. So we analyzed texture, toyo glossiness value, germination rate and lipoxygenase activity of 15 LOX-3 null rice lines on the condition of which rough rice had been stored at different temperatures (high temperature condition at $35^{\circ}C$ and low temperature condition at $15^{\circ}C$ for 4months. Hardness and stickiness of the lines tendered to be increased when it was stored at high temperature and adhesiveness, springiness, cohesiveness and chewiness was not considerably different according to storage temperatures and periods. The germination rate of HR29062-B-98-2-1-B among LOX-3 null rice lines was higher than another lines, 99.3, 94.0% after 4months stored at low temperature and high temperature, respectively. The lipoxygenase activity was 3,304, 1,601unit/mg protein after 4months stored at low temperature and high temperatures, respectively. So, it is thought that this line will be useful to breed rice varieties with high storability after tested on agricultural traits.

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전기 압력 밥솥 밑 전기 밥솥 취반미의 저장 조건에 따른 품질 특성 (The Quality of Cooked Rice Prepared by Both an Electric Cooker and Electric Pressure Cooker, with Different Storage Conditions)

  • 한귀정;박희정;이혜연;박영희;조용식
    • 한국식품조리과학회지
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    • 제23권5호
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    • pp.635-643
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    • 2007
  • 쌀밥의 저장 특성을 조사하기 위하여 국내산 쌀 탑 라이스 4품종(일품, 새추청, 신동진 및 수라)을 전기 압력 밥솥 및 전기 밥솥을 이용하여 취반한 다음 상온, 보온 및 냉장 저장하면서 수분함량, pH, 색도 및 관능적인 특성을 조사하였다. 취반 직후 쌀밥은 전기압력 밥솥으로 취반했을 때 수분함량이 낮고 pH는 높았으며, 색도에서 b값은 높고 L값은 낮은 경향을 보였다. 관능적으로도 구수한 풍미, 조직감 등이 강하고 기호도가 우수한 것으로 나타났다. 저장 기간에 따라서는 수분함량 및 pH는 취반 용기에 관계없이 모든 저장 온도에서 감소하였고, 색도는 상온 및 냉장 보관시에는 취반 용기에 관계없이 L, a 및 b값 모두 저장기간 동안 유사하였으나 보온 조건에서 전기 밥솥 취반미를 저장했을 때는 초기(6시간)에 녹색도 (a값)이 감소하기 시작하여 24시간 후에는 황색도(b값)가 크게 증가하면서 L값이 감소하였다. 관능적으로도 상온에서는 저장 48시간까지 유의적 차이를 보이지 않은 반면 보온 및 냉장 저장 시에는 각각 24시간 및 3일 경과 후에 대부분의 관능적 특성에서 유의적인 차이를 보이면서 기호도가 감소하였다. 이상으로부터 저장 중 쌀밥의 품질은 상온에서는 48시간까지 색도 및 관능적인 변화가 적어 가장 효과적이었던 반면 보온 및 냉장에서는 각각 황변 및 수분증발과 함께 이취가 증가하면서 관능적으로 품질이 낮아졌으며, 전기 압력 밥솥 보다 전기 밥솥을 사용하여 보온했을 때 품질저하가 더 큰 것을 알 수 있었다.

Absorption of SO2 at High Temperatures by Ionic Liquids and the Absorption Mechanism

  • Tian, Shidong;Hou, Yucui;Wu, Weize;Ren, Shuhang;Qian, Jianguo
    • Bulletin of the Korean Chemical Society
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    • 제35권9호
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    • pp.2791-2796
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    • 2014
  • The capture of $SO_2$ at or close to the temperatures of real flue gas is much more attractive in application. In this work, two kinds of ionic liquids (ILs) based on lactate anion were used to absorb $SO_2$ at high temperatures from 100 to $120^{\circ}C$. The ILs show high absorption capacities of over one mol $SO_2$ per mol IL at $110^{\circ}C$. The absorption of $SO_2$ by the ILs based on lactate anion is reversible and the ILs can be reused for the capture of $SO_2$ at high temperatures with high absorption capacity and thermal stability. Furthermore, the absorption mechanism of $SO_2$ by the ILs was studied by FT-IR, $^1H$ NMR and $^{13}C$ NMR spectra. It has been found that there are strong chemical interactions between the ILs and $SO_2$. Also the absorption mechanism is different when there is water present in ILs compared to when there is not.

음료 제조를 위한 오미자 추출물의 추출 조건에 따른 품질 특성 (Quality Characteristics of Omija (Schizandra chinesis Baillon) Extracts Under Various Conditions for Beverage Production)

  • 민성희
    • 한국식생활문화학회지
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    • 제28권3호
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    • pp.320-327
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    • 2013
  • The quality characteristics of Omija (Schizandra chinesis Baillon) extracts under various extraction temperatures and times were examined. The pH level of the extracts ranged from 3.35-3.47. The sugar and solid content of the samples significantly increased with increasing extraction temperatures and times (p<0.01). In contrast, the lightness of the extracts decreased with increasing extraction temperatures and times (p<0.001). In a palatability test, extracts boiled at $80^{\circ}C$ for 30 minutes scored high in terms of color, flavor, turbidity, sourness, and overall acceptability. Hydroxy radical scavenging activity and polyphenol content of the extracts significantly increased with increasing extraction temperatures and times (p<0.01). Furthermore, direct correlations between hydroxy radical scavenging activity and polyphenol content (or flavonoid content) were established through simple regression (r>0.9) for different extraction temperatures and times. From these results, extracts boiled at $80^{\circ}C$ for 120 minutes is the best to product omija beverage considering functionality and sensory evaluation as well.

Impact of Heat Stress on Pollen Fertility Rate at the Flowering Stage in Korean Rice (Oryza sativa L.) Cultivars

  • Thuy, Tran Loc;Lee, Chung-Kuen;Jeong, Jae-Hyeok;Lee, Hyeon-Suk;Yang, Seo-Young;Im, Yeon-Hwa;Hwang, Woon-Ha
    • 한국작물학회지
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    • 제65권1호
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    • pp.22-29
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    • 2020
  • Rice is very sensitive to high temperatures during the reproductive stage, particularly during the flowering and anthesis periods. To determine how high temperatures result in sterility during the flowering period in Korean rice cultivars, groups of 11 cultivars were subjected to different temperature regimes (24, 28, 30, and 33℃) during the flowering stage using sunlit phytotrons. At an average of 33℃, all 11 rice cultivars reached anthesis earlier than at the other temperatures. Microscopy analyses revealed significant differences in pollen germination and pollen viability in cultivars grown at 33℃ compared to those cultured at lower temperatures. At 33℃, the cultivars had significantly lower fertility rates (47% reduction) than cultivars grown at 24℃. These findings are important as rice pollination and fertility depend on the pollen viability and germination. The present study shows that rice fertility is negatively affected by excessively high temperatures.

설명가능한 인공지능을 통한 마르텐사이트 변태 온도 예측 모델 및 거동 분석 연구 (Study on predictive model and mechanism analysis for martensite transformation temperatures through explainable artificial intelligence)

  • 전준협;손승배;정재길;이석재
    • 열처리공학회지
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    • 제37권3호
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    • pp.103-113
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    • 2024
  • Martensite volume fraction significantly affects the mechanical properties of alloy steels. Martensite start temperature (Ms), transformation temperature for martensite 50 vol.% (M50), and transformation temperature for martensite 90 vol.% (M90) are important transformation temperatures to control the martensite phase fraction. Several researchers proposed empirical equations and machine learning models to predict the Ms temperature. These numerical approaches can easily predict the Ms temperature without additional experiment and cost. However, to control martensite phase fraction more precisely, we need to reduce prediction error of the Ms model and propose prediction models for other martensite transformation temperatures (M50, M90). In the present study, machine learning model was applied to suggest the predictive model for the Ms, M50, M90 temperatures. To explain prediction mechanisms and suggest feature importance on martensite transformation temperature of machine learning models, the explainable artificial intelligence (XAI) is employed. Random forest regression (RFR) showed the best performance for predicting the Ms, M50, M90 temperatures using different machine learning models. The feature importance was proposed and the prediction mechanisms were discussed by XAI.

침지된 해수 온도 및 결합재 혼합비에 따른 비소성 시멘트의 강도 특성 (Properties of Non-Sintered Cement Pastes Immersed in Sea Waters at Different Temperatures for Binders Mixed with Different Ratios)

  • 전유빈;김태완
    • 한국구조물진단유지관리공학회 논문집
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    • 제20권5호
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    • pp.75-84
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    • 2016
  • 본 연구에서는 해수 침지 온도에 따른 비소성 시멘트 경화체의 물리적 및 역학적 특성에 대해 비교 분석하였다. 비소성 시멘트는 플라이애시와 고로슬래그미분말을 6:4, 7:3 및 8:2의 중량비로 혼합하여 수산화나트륨과 액상규산나트륨으로 알칼리 활성화 하여 제작되었다. 알칼리 활성화를 위한 활성화제는 플라이애시와 고로슬래그미분말을 혼합한 중량의 5%로 하였으며, 화학첨가제로 탄산칼슘이 사용되었다. 본 연구에서는 알칼리 활성화된 시험체들을 3가지 다른 온도($5^{\circ}C$, $15^{\circ}C$$25^{\circ}C$)의 해수에 각각 침지 시킨 후, 침지 재령 3일 및 28일에 대해 경화체의 압축 강도, 밀도 및 흡수율을 측정하였으며, 해수 침지 재령 28일에 대해서는 XRD 및 SEM 시험 분석을 실시하였다. 또한, 해수 침지 재령 28일에 대하여 시험체들 내의 수용성 염화물(자유염화물) 및 산-가용성 염화물(총염화물) 함유량을 측정하여 분석하였다. 본 연구에서 해수온도별로 침지시킨 플라이애시-고로슬래그미분말 혼합 알칼리 활성화 경화체는 플라이애시 혼합률이 증가함에 따라 밀도 감소, 흡수율 증가 및 강도가 감소하는 경향을 나타냈다. 또한 플라이애시 혼합률이 증가할수록 시험체 내의 수용성 염화물 및 산-가용성 염화물의 양이 증가하는 것으로 나타났다. 본 연구에서 제작된 플라이애시-고로슬래그미분말 혼합 알칼리 활성화 경화체는 노출된 해수 온도 영향으로 인한 강도 차이는 없는 것으로 판단되며, 플라이애시와 고로슬래그미분말의 혼합중량비에 따라 강도 특성이 달라지는 것으로 나타났다.