• Journal of the Korean Society for Heat Treatment
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• v.23 no.5
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• pp.263-268
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• 2010

This investigation was focused on the low temperature tensile properties, phase change, changes in nitrogen content and corrosion resistance in the 22Cr-5Ni-3Mo duplex stainless steel after high temperature gas nitriding and solution annealing (HTGN-SA). From the HTGN-SA treatment, the duplex (ferrite + austenite) phase changed into austenite single phase. The nitrogen content of austenite single-phase steel showed a value of ~0.54%. For the HTGN-SA treated austenitic steel, tensile strength increased with lowering test temperature, on the other hand elongation showed the maximum value of 28.2% at $-100^{\circ}C$. The strain-induced martensitic transformation gave rise to lead the maximum elongation. After HTGN-SA treatment, corrosion resistance of the austenite single-phase steel increased remarkably compared with HTGN- treated steel.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.1
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• pp.94-101
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• 2015

The heat treatment machine based on immersion was developed to reduce temperature difference during netting process and appraised it performance compared current heat treatment machine using high pressure. It was also reviewed the optimum heat treatment procedures for PBSAT monofilament net in accordance with the immersion time and temperature. The procedure was based on physical measurement such as breaking load, elongation and angle of the mesh for PBSAT monofilament. The water temperature gap of the treatment machine based on immersion was less than $1^{\circ}C$. and the energy consumption was also increased in high temperature condition. It was identified that the optimum temperature was $75^{\circ}C$ and its optimum processing time was between 15 minutes and 20 minutes to get qualified physical properties.

• Journal of the Korean institute of surface engineering
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• v.48 no.3
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• pp.93-99
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• 2015

This test focuses on the correlations between joining axial force at non-room temperature and at room temperature according to the surface treatment (Geomet, Dacro, Green Kote, Armore Galv.). The quality characteristics of the fastening axial force required by the KSB 2819 and EN14399-10 standards were discussed. Surface treatment was implemented to S10T and 10.9HRC sets of bolts under the same environmental factors. Development for the stabilization of the fastening axial force required by each standard should continually be enforced, and the fastening and storage in the field should be maintained at room temperature. Managing stabilization of torque enumerated data is required after application of surface treatment. It is concluded that, by conducting the test of applying surface treatment to effectively manage, each lot-specific rate of axial force at room temperature conditions should be maintained below the maximum 4.47%. The decline rate of axial force should be maintained under 2.15% maximum, and the standard deviation of the room temperature condition should be maintained below 0.5.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.559-562
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• 2006

A low-temperature solar thermal system assisting a biological nitrogen treatment reservoir was designed and field-tested. A large tank whose temperature was maintained at about $25{\sim}30^{\circ}C$ to enhance the performance of a biological nitrogen treatment process was heated by an array of flat plate solar collectors. Test results revealed that the overall collector efficiency was above 50% for the most cases tested. This high efficiency was possible owing to the relatively low collector temperature that can be traced back to the reservoir temperature. A substantial enhancement in nitrogen treatment was observed as a result of maintaining the reservoir temperature higher.

• Journal of Environmental Science International
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• v.27 no.4
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• pp.251-259
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• 2018

This study was conducted to determine the effects of combination of air temperature and soil water content on the growth, physiological disorder rate, and yield of hot peppers. The study was carried out in a typical plastic house (open on one side and with ventilation fans on the other side), which was maintained with gradient air temperature (maximum difference in air temperature: $6^{\circ}C$). The deficit irrigation (DI) treatment commenced 65 days after transplanting. The height of plant and fresh and dry weights of the stem increased at high air temperature (ambient + $6^{\circ}C$, extreme high temperature; EHT). Furthermore, the leaf area decreased significantly with the DI treatment. There were no significant differences in the stem diameter, number of branches, and fresh and dry weights of the leaves among all the treatments. The net photosynthesis rate of the full irrigation (FI) treatment was higher than that of the DI treatment. The photosynthesis rate at ambient air temperature was $19.7{\mu}mol\;CO_2m^{-2}{\cdot}s^{-1}$, the highest among all the treatments; however, the photosynthesis rate of the EHT treatment decreased by 60% ($12.3{\mu}mol\;CO_2m^{-2}{\cdot}s^{-1}$). Additionally, the formation of guard cells in the leaf was abnormal with the EHT treatment, and there was a decrease in translocation efficiency. The effects of air temperature treatment were more pronounced on the physiological disorder rate and yield. The physiological disorder rate of the EHT treatment was the highest under the DI treatment condition. The yield of the AFI (ambient air temperature with full irrigation) treatment was 3,771 kg/10a, the highest among all the treatments; however, the yield of the EHT treatment with DI and FI was 1,282 and 1,327 kg/10a, respectively. These results indicate that growth and physiological disorder rate improved with the EHT treatment; however, there was a decrease in yield. Furthermore, the formation of guard cells was abnormal and malfunctional.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.59-62
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• 1998

Thermal treatment dependences of MFS devices in $BaMgF_4$ on Si structures have been investigated. $BaMgF_4$ thin films have been directly deposited on the p-Si(100) wafers at a low temperature of $300^{\circ}$ in an ultra high vacuum(UHV) system. After in-situ post-deposition annealing was conducted for 20 s at $650^{\circ}$, bias and temperature were applied to $BaMgF_4/Si$ structures. Although X-ray diffraction analysis showed that the films were polycrystalline in nature before and after bias temperature, the C-V properties were some different between with and without bias-temperature treatment.

• Journal of the Korean Solar Energy Society
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• v.28 no.2
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• pp.34-41
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• 2008

A low-temperature solar thermal system assisting a biological nitrogen treatment reservoir was designed and field-tested. A large tank whose temperature was maintained at about $25-30^{\circ}C$ to enhance the performance of a biological nitrogen treatment process was heated by an array of flat plate solar collectors. Test results revealed that the overall collector efficiency was above 50% for the most cases tested. This high efficiency was possible owing to the relatively low collector temperature that can be traced back to the reservoir temperature. A substantial enhancement in nitrogen treatment was observed as a result of maintaining the reservoir temperature higher.

• Journal of Dairy Science and Biotechnology
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• v.35 no.2
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• pp.121-133
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• 2017

A small amount of milk is sold as 'untreated' or raw in the US; the two most commonly used heat-treatments for milk sold in retail markets are pasteurization (LTLT, low-temperature long time; HTST, high-temperature short time) and sterilization (UHT, ultra-high temperature). These treatments extend the shelf life of milk. The main purpose of heat treatment is to reduce pathogenic and perishable microbial populations, inactivate enzymes, and minimize chemical reactions and physical changes. Milk UHT processing combined with aseptic packaging has been introduced to produce shelf-stable products with less chemical damage than sterile milk in containers. Two basic principles of UHT treatment distinguish this method from in-container sterilization. First, for the same germicidal effect, HTST treatments (as in UHT) use less chemicals than cold-long treatment (as in in-container sterilization). This is because Q10, the relative change in the reaction rate with a temperature change of $10^{\circ}C$, is lower than the chemical change during bacterial killing. Based on Q10 values of 3 and 10, the chemical change at $145^{\circ}C$ for the same germicidal effect is only 2.7% at $115^{\circ}C$. The second principle is that the need to inactivate thermophilic bacterial spores (Bacillus cereus and Clostridium perfringens, etc.) determines the minimum time and temperature, while determining the maximum time and temperature at which undesirable chemical changes such as undesirable flavors, color changes, and vitamin breakdown should be minimized.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.4
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• pp.425-433
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• 2006

Sepiolite was selected as a mineral carbonation candidate ore for carbon dioxide sequestration. Carbonation salt formation from alkaline earth metal ingredient needs to dehydroxylation of sepiolite at high temperature. An evident dehydroxylation was observed over $800^{\circ}C$ and the variations of sepiolite characteristics after high temperature treatment was synthetically evaluated. Remarkable weight loss were measured after high temperature thermochemical reaction then crystallographic and spectroscopic changes were analyzed. The resulted alkaline earth metal oxides could explained by dehydroxylation based on thermochemical reaction.

• Journal of the Korean Wood Science and Technology
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• v.46 no.2
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• pp.149-154
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• 2018

The changes in sound absorption capability and air permeability of Malas wood after high temperature heat treatment were investigated. The average air permeability of Malas in longitudinal direction after heated under the temperature of $190^{\circ}C$ during 3 hours was about 23.48 darcys and that of control was about 3.11 darcys. The noise reduction coefficients of Malas specimens were 17% for treatment and 10% for control. The means of sound absorption coefficient of specimens in the frequency range of 50~6,400 Hz were 42% for treatment and 17% for control, respectively.