• Korean Journal of Metals and Materials
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• v.50 no.7
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• pp.495-502
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• 2012

The aim of this study was to analyze high temperature deformation stability and properties of duplex stainless steels(DSS) according to annealing temperature. In order to analyze high temperature deformation stability, a number of compression tests were carried out with a stain rate of $10^{-2}s^{-1}{\sim}10s^{-1}$ up to a compression ratio of 50% in a temperature range of $950^{\circ}C-1300^{\circ}C$. The analysis of high temperature deformation stability of DSS was performed based on the Ziegler model. In order to analyze the high temperature properties of DSS, annealing treatments were conducted by isothermal holding for 1 hr at $950^{\circ}C$ to $1300^{\circ}C$ with $50^{\circ}C$ intervals followed by water cooling. The hardness and tensile tests were performed on specimens with different volume fractions of constituent phases, such as austenite, ferrite and sigma. The hardness and tensile strength of 2507 according to the annealing temperature are better than those of 2205. The strain rate sensitivity and Ziegler parameter are higher in 2205 than in 2507 as a whole, which implies that 2205 is better than 2507 in terms of forgeability at high temperature.

• Korean Journal of Medicinal Crop Science
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• v.27 no.4
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• pp.278-283
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• 2019

Background: High temperature damage in ginseng is influenced by shading materials related not only to temperature, but also to light intensity and light quality. To address, this green-colored khaki shading sheet is widely used. As they are recently, developed, there is limited research information about their attributes and use. Methods and Results: The four-layered shading net (FLSN), blue-colored shading sheet (BCSS), aluminum-coated shading board (ACSB), and green-colored shading sheet (GCSS) were installed in the wooden A type of sun-block facilities. Two layered black, shading net was additionally used to cover the facilities since the beginning of June. The average temperature at the facility where different shades were tested was in the order of BCSS ($28.9^{\circ}C$) > FLSN ($27.7^{\circ}C$) > GCSS ($27.6^{\circ}C$) > ACSB ($27.1^{\circ}C$). However, high temperature injury rates were in order: FLSN > ACSB > GCSS > BCSS. Root weight vaired and was in the order: ACSB > GCSS > BCSS > FLSN. Conclusions: High temperature damage is possible not only because of temperature increase, but also due to various environmental light factors. Ginseng high temperature injury was minimal when BCSS or GCSS were used by difference of light quality. Although the root weight was higher in ACSB, it could be vulnerable to high temperature damage. Therefore, we propose using GCSS for ginseng shading.

• Journal of fish pathology
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• v.19 no.3
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• pp.235-241
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• 2006

The effects of various temperature shifts on the kinetics of the humoral antibody response in oliver flounder, Paralichthys olivaceus, immunised with formalin-killed Edwardsiella tarda, were determined by measuring the antibody production in vivo and in vitro. When fish acclimated to a high temperature and immunised at that temperature were transferred to a lower temperature (22℃ to 12℃) at a various times after immunisation, the fish showed a weaker immune response than that achieved when the fish were kept at a high environmental temperature. However, in the converse experiment (12℃ to 22℃), the magnitude of the humoral immune response was recovered independent of the time of the transfer after immunisation at low temperature, even though the peak levels of each transferred group did not reach the level found in the positive control group that was maintained and immunised at a high environmental temperature. Hence, these studies provide some evidence that the potential for antibody production in B cells of oliver flounder immunized at high temperature is not impaired by subsequent exposure to low temperature.

• Journal of the Korean Ceramic Society
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• v.51 no.4
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• pp.271-277
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• 2014

To overcome the limitations of the solid oxide fuel cells (SOFCs) due to the high temperature operation, there has been increasing interest in proton conducting fuel cells (PCFCs) for reduction of the operating temperature to the intermediate temperature range. In present work, the perovskite $BaCe_{0.85-x}Zr_xY_{0.15}O_{3-\delta}$ (BCZY, x = 0.1, 0.3, 0.5, and 0.7) were synthesized via solid state reaction (SSR) and adopted as an electrolyte materials for PCFCs. Powder characteristics were examined using X-ray diffraction (XRD), thermogravimetric analysis (TGA) and Brunauer, Emmett and Teller (BET) surface area analysis. Single phase BCZY were obtained in all compositions, and chemical stability was improved with increasing Zr content. Anode-supported cell with $Ni-BaCe_{0.55}Z_{0.3}Y_{0.15}O_{3-\delta}$ (BCZY3) anode, BCZY3 electrolyte and BCZY3-$Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}O_{3-\delta}$ (BSCF) composite cathode was fabricated and electrochemically characterized. Open-circuit voltage (OCV) was 1.05 V, and peak power density of 370 ($mW/cm^2$) was achieved at $650^{\circ}C$.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.1
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• pp.173-179
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• 1997

The high temperature fatigue tests were performed using the specimens taken from Cr-Mo-V steel, widely used as thermal power plant turbine materials for examination fatigue behavior of materials in power plants which have been operated for long periods. The fatigue tests at high temperature were performed at the various temperature and applied stress. The results obtained are summarized as follows : The fatigue crack length increases and the fatigue life decreases with temperature and applied stress according to the same number of stress cycle. The fatigue crack propagation and the fatigue life were much influenced by temperature and applied stress.

• 한국연소학회:학술대회논문집
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• 2001.11a
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• pp.104-110
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• 2001

Characteristics of lifted flame for highly diluted propane with nitrogen in high temperature coflowing air have been experimentally investigated, and the stabilization mechanism of lifted flame in high temperature air coflow have been proposed. As the coflow temperature increases, the liftoff height of flame decreased due to the increase of stoichiometry laminar burning velocity. At same coflow temperature, the difference of liftoff height between the fuel mole fractions has been disappeared by scaling the liftoff velocity with stoichiometry laminar burning velocity. It has been found that lifted flame can be stabilized for even smaller fuel velocity than stoichiometry laminar burning velocity. This can be attributed to buoyancy effect and the liftoff velocity characteristics for coflow temperature support it.

• Tribology and Lubricants
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• v.23 no.1
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• pp.1-8
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• 2007

Turbocharger bearings are under the circumstance of high temperature, moreover rotated at high speed. It is necessary to be designed to overcome the high temperature. So the type of oil inlet port, the inlet oil temperature and the sort of engine oil should be designed, controlled and selected carefully in order to reduce the bearing inside temperature. Therefore, in this study, the effects of the type of inlet oil port, inlet temperature and the sort of engine oil on the performance of a turbocharger bearing are to be investigated. It is found that the type of oil inlet ports, the control of inlet oil temperature and the selection of engine oil type play important roles in determining the temperature and pressure, then the friction and load of a turbocharger journal bearing at high speed operation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.12
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• pp.1123-1127
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• 2006

There are various elements that have influence on safety and reliability of high speed railway. Among them, mechanical characteristics of traction motors are very important. Therefore, we verified that temperature characteristics have influence on damage and durability of these parts. We designed a measurement system for temperature test, and could measure the temperature of each device by the system. As the result of temperature test, we could confirm that the traction motors on Korean High-Speed Train satisfy the criteria. From this test, we get information of the traction motor about the temperature characteristic during running speed and running time.

• Carbon letters
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• v.2 no.1
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• pp.9-14
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• 2001

Adsorption and desorption characteristics of methyl iodide at high temperature conditions up to $250^{\circ}C$ by TEDA-impregnated activated carbon, which is used for radioiodine retention in nuclear facility, was experimentally evaluated. In the range of temperature from $30^{\circ}C$ to $250^{\circ}C$, the adsorption capacity of base activated carbon decreased sharply with increasing temperature but that of TEDA-impregnated activated carbon showed higher value even at high temperature ranges. Especially, the desorption amount of methyl iodide on TEDA-impregnated carbon represented lower value than that on unimpregnated carbon. The breakthrough curves of methyl iodide in the fixed bed packed with base carbon and TEDA-impregnated activated carbon at high temperature were compared. TEDA-impregnated activated carbon would be applicable to adsorption process up to $150^{\circ}C$ for the removal of radioiodine in a nuclear facility.

• Journal of Power System Engineering
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• v.10 no.4
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• pp.31-37
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• 2006

In this study, the ability for the function of double pipe inserted liquid pipe with small diameter in the gas pipe with large diameter for the circulating of liquid of high temperature and high pressure and low temperature and low pressure at the same time is presented. And in this double pipe, liquid pipe of high temperature and pressure is used to connect condenser and expansion valve and gas pipe of low temperature is used to connect evaporator and compressor. Also, when liquid refrigerant of high temperature and gas refrigerant of low temperature is circulated by reversed flow in the double pipe. The contribution of liquid gas heat exchange pipe is studied by comparison of the effect of heat transfer by temperature difference when liquid pipe and gas pipe is installed separately.