• Title/Summary/Keyword: Elevated temperature condition

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Studies on the Effect of 'Gal Geun Tang' upon Stress Resistance of Rats (갈근탕(葛根湯) 투여가 흰 쥐의 스트레스 저항 반응에 미치는 영향에 관한 연구)

  • Kwon, Chang-Ho
    • Korean Journal of Pharmacognosy
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    • v.5 no.4
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    • pp.217-222
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    • 1974
  • Oxygen consumption rate has been determined to study the effect of 'Gal Geun Tang' upon stress resistance of rats. The oxygen consumption rate of liver tissue increased slightly when normal rats were given the Gal Geun Tang infusion only. When rats were given the infusion after an injection of typhoid vaccine, the elevated boby temperature and oxygen consumption rate due to typhoid vaccine fell to normal level. From this result, it is concluded that 'Gal Geun Tang' has a function that may normalize abnormally strained liver metabolism. Oxygen consumption rate of the rats significantly increased when rats were exposed to cold condition. However, under the same condition it rather maintained the normal consumption rate when the rats were given previously "Gal Geun Tang". It is suggested that 'Gal Geun Tang' has an effects that impairs the immune response from cold stress. The rats that were given Cinnamomi Ramulus('Ge Ji Tang') showed less effect than the group of 'Gal Geun Tang'.

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Note-PC Case Fabrication by Magnesium Alloy Sheet Press Forming (마그네슘 판재 프레스 성형에 의한 노트PC 케이스 제작)

  • Kim, H.K.;Woo, S.S.;Lee, J.;Heo, Y.M.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2008.05a
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    • pp.337-340
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    • 2008
  • Magnesium alloy is expected to be widely used for mobile electronic appliances as well as automobile parts for its lightweight and EMI-shielding characteristics. In the present investigation, a Note-PC upper case made of magnesium alloy AZ31 sheet was developed by using the press forming technology at elevated temperature. Considering the press forming process and the formability of magnesium alloy sheet, the case shape and the press die was designed. The optimum forming condition was experimentally examined. Then the as-received magnesium alloy sheet was press-formed into the designed case shape under the optimum forming condition.

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Evaluation of yield and growth responses on paddy rice under the extremely high temperature using temperature gradient field chamber (온도구배야외챔버를 이용한 고온에서의 벼 생육반응 및 수량성 평가)

  • Oh, Dohyeok;Ryu, Jae-Hyun;Cho, Yunhyeong;Kim, Wonsik;Cho, Jaeil
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.20 no.1
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    • pp.135-143
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    • 2018
  • The effect of elevated temperature on temperate paddy rice will be significant for dependable food supply in East Asia. Using temperature gradient field chamber (TGFC), which was designed to make the horizontal air temperature gradient by $0^{\circ}C$ to $3^{\circ}C$ higher than outside, we examined the measurement to understand the effects of extremely high temperature on paddy rice. In particular, the data of the year 2016, the worst heat wave in over 22 years, was analyzed in this study. The rice height in the relatively warmed condition was rapidly increased during early growth stage. However, the average grain weight and number of spikelet per panicle in the warmed chamber condition were gradually declined with increasing air temperature averaged for 40 days after first heading in each chamber. In particular, the grain yield was more dramatically decreased by the raising temperature because the percent ripened grain was quickly dropped as getting over the threshold temperature for pollination. Therefore, the surplus photosynthetic product by such lower grain filling rate may disturbed the decreases of the NDVI (Normalized Difference Vegetation Index) and SPAD chlorophyll values after first (normal) heading. In addition, the late-emerging head grain were appeared. However, this yield was too small to recover the normal yields decreased by extremely high temperature condition. Our result represented that the warmed condition in 2016 would be the critical limit for the stable yield of temperate paddy rice.

The Phenological Responses of Leaf of Deciduous Woody Species to Base Temperature Maintenance (수목 최저 생육온도 이상으로 유지된 조건에서의 한반도 주요 수목 잎의 식물계절학적 반응)

  • Hong, Yongsik;Lee, Seungyeon;Lee, Sooin;Lee, Eungpill;Kim, Euijoo;Park, Jaehoon;Jeong, Heonmo;You, Younghan
    • Korean Journal of Ecology and Environment
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    • v.51 no.4
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    • pp.259-267
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    • 2018
  • This study was conducted to confirm phenological response of main deciduous woody species in Korea according to elevated temperature. Based on seeds collected from the same place, 39 woody species were cultivated in field (control) and in greenhouse (treatment) that was maintained above base temperature ($4.8^{\circ}C$). And then, we observed phenotype change of leaves focused on phenological response and explained relation with their current distribution area. As a result, initiation period of leaves unfolding was 1st~3rd, May in control. It was 13, December~7, January in treatment. Period of leaves yellowing was 11~26, October in control. It was 30, October~13, November in treatment. Consequently, initiation period of leaves unfolding was faster by 119~140 days and period of leaves yellowing was slower by 3~32 days since elevated temperature. Period of leaves growth increased in treatment by 148 days than control. Quercus mongolica and Quercus serrata that cultivated in treatment was changed as evergreen trees which have grown up continuely during one year. Also, initiation period of leaves unfolding of Sorbus alnifolia in treatment was faster than in control. However, difference of the period between control and treatment was smallest. Because period of yellowing leaves was moved ahead. Phenological response of leaves according to elevated temperature had no relation of type of their current distribution area. This is the result of acclimation due to elevated temperature during the winter and suggests that the phenotype of leaves of 39 deciduous woody species is more sensitive to the current growth condition than to the past growth condition.

Evaluation on Thermal Strain Behavior Properties of Ultra High Strength Concrete considering Load (하중재하조건을 고려한 초고강도 콘크리트의 열변형거동특성 평가)

  • Lee, Young-Wook;Kim, Gyu-Yong;Choe, Gyeong-Cheol;Kim, Hong-Seop;Lee, Bo-Kyeong;Yoon, Min-Ho
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2015.11a
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    • pp.162-163
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    • 2015
  • Thermal deformation behavior of high-strength concrete (HSC) exposed to fire is different from that of normal strength concrete (NSC). In case of ultra-high-strength concrete (UHSC), it is well known that thermal deformation behavior is greater than HSC. With increasing research of UHSC in buildings, it is necessary to understand the performance of UHSC at elevated temperatures considering loading condition. Therefore, evaluation on properties of thermal strain behavior properties of ultra high strength concrete by loading and high temperature was conducted.

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Synthesis and Properties of Self-hardening Calcium Phosphate Cemetns for Biological Application

  • Song, Tae-Woong;Kim, Han-Yeop
    • The Korean Journal of Ceramics
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    • v.3 no.2
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    • pp.129-133
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    • 1997
  • Fine powder of $\alpha$-tricalcium phosphate, tetracalcium phosphate and dicalcium phosphate were mixed together to prepare self-setting cements which form hydroxyapatite, one of the well-known biocompatible materials, as the end of products of hydration. Hardening behaviour of the cements was examined at the temperature range of 37~$70^{\circ}C$ and 150~$250^{\circ}C$ under the normal and hydrothermal condition respectively. The conversion of cements into hydroxyapatite was significantly improved ast elevated temperature and the paste was strengtheed by interlocking of hydroxyapatite crystals, indicating that the strength is determined by microtexture rather the amount of conversion of cements into hydroxyapatite.

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Thermal Strain Properties of Ultra High Strength Concrete according to the Compressive Strength (압축강도에 따른 초고강도 콘크리트의 열변형 특성)

  • Yoon, Min-Ho;Kim, Gyu-Yong;Choe, Gyeong-Cheol;Hwang, Eui-Chul;Lee, Bo-Kyeong;Seo, Won-Woo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2016.10a
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    • pp.24-25
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    • 2016
  • In this study, the thermal strain of high strength concrete with the compressive strength of 80, 130, 180MPa were measured under 25% of compressive strength loading condition. As results, it is considered that decline of the elastic modulus and shrinkage strain of high strength concrete become grater at the elevated temperatures.

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The Microstructures and Mechanical Properties on the GTA Welding conditions of Inconel 617 (Inconel 617 GTA 용접조건에 따른 미세조직 특성 및 기계적성질)

  • Choe, Seong-Bu;Lee, Bong-Geun;Gang, Jeong-Yun
    • Proceedings of the KWS Conference
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    • 2005.11a
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    • pp.171-173
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    • 2005
  • Inconel 617 is a solid solution, nickel-chromium-cobalt-molybdenum alloy with an exceptional combination of high temperature strength and oxidation resistance. The combination of high strenth and oxidation resistance at temperatures over $1800^{\circ}F$ makes Inconel 617 an attractive material for such components as ducting, transition liners in both aircraft and gas turbine. In this study, the weldability and weldment characteristics of Inconel 617 are considered in GTAW associated with the two welding current and with back shielding gas using or not. After GTAW with 120A and 150A current, microstructures and hardness test, bending test, tensile test on room and elevated temperature for the determination of optical welding condition.

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Color Changes according to the Extraction Condition of Caesalpinia sappan Dyestuff I (소목 염료의 추출조건이 색상에 미치는 영향 I)

  • Jeon, Hee-Young;Choi, Se-Min;Ahn, Jeong-Hoon;Jeon, Dong-Won
    • Journal of Fashion Business
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    • v.13 no.2
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    • pp.136-144
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    • 2009
  • The purpose of this study is to investigate various phenomena quantitatively occurring during the course of changing dyeing conditions of cotton and silk fibers in natural dyeing using Caesalpinia sappan. Paying attention to the fact that the color may be varied according to the extraction conditions of dyestuffs in Caesalpinia sappan dyeing, the color changes were investigated after dyeing using dyestuffs extracted at elevated temperature and dyestuffs extracted at room temperature. According to the extraction methods, the degree of color development for the category of red color and the category of yellow color has changed.

A study on lubrication characteristics in warm deep drawing of magnesium alloy sheet (마그네슘합금의 온간 딥 드로잉 공정에서의 윤활 특성 연구)

  • Park, S.H.;Kim, S.W.;Lee, Y.S.;Kim, B.M.;Lee, J.H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2007.10a
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    • pp.306-309
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    • 2007
  • Recently, magnesium alloys have been widely used in automotive, aerospace and electronic industries with the advantages such as lightweightness, high specific strength and stiffness. However, magnesium alloy has quite low formability at room temperature due to its hexagonal close-packed crystal structure. Warm deep drawing is one of the forming technologies to improve the formability of magnesium alloy sheet and the lubrication condition is an important process parameter in that. In this study, the drawing tests of AZ31 alloy sheet at elevated temperature for various kinds of lubricant were carried out and the effects of lubrication conditions on drawbility were investigated.

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