• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.137-140
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• 2001

To improve structural properties and induce higher conductivity, we have annealed emitting layer, The temperature condition was investigated by various experiment. To observe the surface morphology of emitting layer, measured the AFM and the X-ray diffraction pattern of P3HT film is shown. It is move to slightly low angles and diffraction peaks also become much sharper. After annealing of emitting layer, EL intensity and Voltage-current-luminance curve is better as compared with untreated. But PL intensity was decreased. It is known that by emission principal. After annealing of emitting layer, EL devices enhances the interface adhesion between the emissive polymer and Indium-tin-oxide electrode, which takes a critical role to improve the emitting properties of EL devices.

• Journal of the Korean institute of surface engineering
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• v.45 no.5
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• pp.193-197
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• 2012

The influence of annealing process in an $O_2$ atmosphere on the photoluminescence (PL) spectra properties of ZnS nanowires has been investigated. ZnS nanowires with the diameters approximately 100 nm and the lengths a few tens micrometers were synthesized by evaporating ZnS powders on Si substrates while using an Au thin film as a catalyst. ZnS nanowires had an NBE emission band at 430 nm in the violet region. The emission intensity was improved drastically by a process in which ZnS nanowires were heat-treated at $500^{\circ}C$ in an $O_2$ atmosphere for 45 minutes.

• Nuclear Engineering and Technology
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• v.55 no.10
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• pp.3808-3814
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• 2023

The thermal stability of nitric acid solutions after contact with non-irradiated and irradiated tributyl phosphate (TBP) and its solution in Isopar-M has been studied. It has been established that exothermic processes occur during heating due to the interaction of soluble radiolysis products and the decomposition of the extractant with nitric acid. Such processes can occur at temperatures below 100 ℃, but unlike a thermal explosion that occurs in seconds, they are longer in time and are accompanied by weak heat evolution. Their intensity depends on the composition of the extractant, the concentration of HNO₃, and the volume ratio of the organic and aqueous phases. The presence of extractant degradation products in raffinates does not pose a risk of a rapid evolution of gaseous products during evaporation, however, the presence of reducing agents can significantly increase the intensity of the exothermic decomposition of raffinates.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.6
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• pp.904-911
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• 2019

Objective: The study was conducted to evaluate the effects of night light regimen on growth performance, antioxidant status and health of Lingnan Yellow broiler chickens from 1 to 21 days of age. Methods: A completely randomized factorial design involved 2 photoperiods (constant lighting [CL], 24 L:0 D and intermittent lighting [INL], 17 L:3 D:1 L:3 D)${\times}2$ light intensities (10 lx and 30 lx). A total of one thousand six hundred and eighty 1-d-old Lingnan Yellow broiler chicks were randomly divided into 4 treatments with 6 replicates (70 birds per replicate). The experiment lasted for 21 d. Results: Photoperiods and light intensities had no effect on average daily gain, feed conversion ratio, and mortality of the broiler chickens (p>0.05). The INL had a significant effect on average daily feed intake (p<0.05) of broiler chickens compared with CL. Photoperiod and light intensity had an interactive effect on melatonin (MT) concentration (p<0.05). At CL, reducing light intensity increased MT concentration; INL birds had higher MT but MT concentration was not affected by light intensity. There was an interactive effect on glutathione peroxidase (GPx) and catalase (CAT) in serum and total antioxidant capability (T-AOC) in liver between photoperiod and light intensity. With the decrease of light intensity, the activities of GPx and CAT in serum and T-AOC in liver increased in CL group (p<0.05). Broiler chickens reared under INL had better antioxidant status and 10 lx treatments had higher activities of CAT in serum than 30 lx (p<0.05). Different photoperiods and light intensities had no effect on malondialdehyde. There was an interaction between photoperiod and light intensity on serum creatine kinase (CK) concentration (p<0.05). At CL, the elevated light intensity resulted in an increase in CK content; INL birds had lower CK concentration especially in low light intensity group. Besides, INL and low light intensity significantly reduced the concentration of serum corticosterone and heat shock protein 70 (p<0.05). Serum immunoglobulin M contents were increased in broiler chickens reared under the INL compared with CL group (p<0.05). Conclusion: Results above suggest that the night light regimen of INL and 10 lx could be beneficial to the broiler chickens from 1 to 21 days of age due to the better health status and electricity savings.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.857-864
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• 2013

This study was investigated the effects of heat treatment on polyphenolic compounds and antioxidant activities of yacon. Raw yacon was heated at $100^{\circ}C$ and $121^{\circ}C$ for 15, 30, or 60 min by using an autoclave. The browning intensity, levels of free and bound phenolic and flavonoid compounds, and 1,1-diphenyl-2-picrylhydrazyl(DPPH) and 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS) radical-scavenging activity of yacon extracts following heat treatment were measured. The browning index, free polyphenolic content, and antioxidant activities in the extracts were significantly increased (p<0.05) with both increased heating temperature and time, while bound polyphenolic levels were decreased. The levels of free phenolic and flavonoid compounds in the yacon extract heated to $121^{\circ}C$ for 60 min were increased by 1.2 and 1.1 folds compared to raw yacon respectively. Moreover, DPPH and ABTS radical-scavenging activities of the yacon heated to $121^{\circ}C$ for 60 min were 1.7 fold and 2.0 fold higher, respectively, than those of raw yacon. A significant (p<0.01) correlation was observed among browning intensity, free and bound phenolic and flavonoid levels, and DPPH and ABTS radical-scavenging activities in heated yacon extract. Thus, heat treatment can be used as a method to enhance the antioxidant compound content in and the antioxidant activity of yacon.

• Food Science of Animal Resources
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• v.30 no.5
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• pp.851-859
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• 2010

This study was conducted to investigate the application of a model system using an MS-electronic nose based on the discriminative function analysis on volatile flavors, to prediction of the shelf-life of market milk by preservation temperature and differently-loaded heat treatment. On mass spectrum, the ion fragments of volatile flavors of milk obtained from MS-electronic nose could be distinguished at amu 60, 91, 92, and 93. The response levels of volatile flavors at each amu increased in proportion to the heat treatment loaded to the milk, in the order of LTLT, HTST, and UHT. This study indicated that the discriminative function scores of the volatile flavors seemed to correlate with the preservation temperature, storage period, and heat treatment conditions; DF1 (discriminative function first score) showed a strong relationship to storage periods, with $r^2$ of 0.9965, 0.9965, and 0.9911 at temperatures of 4, 7, and $10^{\circ}C$, respectively, while DF2 was influenced by heat treatment conditions with an $r^2$ of 0.9861 at $4^{\circ}C$. It is suggested that the discriminative function analysis given by an MS-electronic nose could be used to construct a new quality control model system for the evaluation of heat treatment loaded during the processing of milk, and for predicting storage periods of market milk.

• Korean Journal of Food Science and Technology
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• v.22 no.6
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• pp.640-645
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• 1990

Changes of the electrophoretic patterns of myofibrillar proteins by sugar audition and heat treatment was studied. In the electrophoretic patterns of myofibrills prepared from no sugar added meat, as the intensity of higher molecular weight band such as myosin heavy chain showed a remarkable decrease by heating, that of lower molecular weight band such as actin showed no change. That from sugar added meat showed more remarkable decrease in the intensity of higher molecular weight band than that from no sugar added meat and this tendency was most noticeable in case of glucose addition. The effect of digestion with proteases after sugar addition and heat treatment on the electrophoretic patterns exhibited the descending order of trypsin >chymotrypsin >peptidase. By digestion with these three enzymes at one time myosin produced 27.000 dalton and 32.000 dalton components, and actin showed 16,000 dalton component. in the case of heat treatment, a part of actin was not digested. And in the case of glucose addition the myosin aggregates was not digested with these three enzymes at a time.

• Solar Energy
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• v.13 no.1
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• pp.22-30
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• 1993

This Paper deals with the experimental study of the axisymmetric air jet impinging vertically on the flat heating surface with and without swirl. The purpose of this study is to investigate the characteristics of flow, augmentation of heat transfer rate, turbulent intensity, and the comparison of heat transfer rate, the optimal swirling condition about the swirl and nonswirl axisymmetric air jet. In order to augment the heat transfer on the flat heating surface without introducing any additional power, the technique used in the present work was placement of twisted tape inserted pipe in front of the nozzle exit in order to make a swirl. The effect of swirl degree is investigated in case of S=0., 0.056, 0.111, 0.222 and the velocity of the jet was 14, 20, 26, 32, 38, 44m/s. The distance between the nozle exit and the stagnation point on the impinging plate was the H/D=$1{\sim}14$. In order to analyze of the flow structure which increase heat transfer, the velocity and the turbulent intensity of the axisymmetric jet was measured by a hot wire anemometer according to the swirl number and H/D.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.4
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• pp.371-381
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• 2012

This study investigates quantitative wear training effects and involved 15 participants from a previous study (part 1) in May to September 2009. Before wear training, the subjects' rectal temperature, skin temperature, heart rate, blood pressure and local sweating were measured for 1 hour in a climate chamber ($39{\pm}1^{\circ}C$, $65{\pm}5%RH$, 0.3m/s) to evaluate heat tolerance. Subsequently, the subjects were divided into 3 groups that consisted of 5 participants. Group N (control-group) dressed the participants so that they felt comfortable (or cool). Group W and MW where participants underwent regular wear training for 10 weeks (5 days a week a total of 50 times). The intensity of the wear training for the participants of group MW was stronger than that for group W. A heat-tolerance experiment was performed after wear training. The results were as follows: 1. The participants of groups W and MW felt more comfortable after wear training than before wear training in the case of warmer $T_{cl}$. However, no significant differences were observed before and after wear training for group N. 2. The heat tolerance of the participants of groups W and MW was higher after wear training than before wear training. However, no significant difference was noted in this regard for group N. 3. The results showed the wear training effect (based on quantitative guidelines). The results show that the predicted optimal temperature inside clothing can enhance heat tolerance.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.789-794
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• 2000

The Paper studies the flow and heat transfer characteristics to a jet impinging at different oblique angles, to a plane surface by numerical methods. The flowfield and heat transfer rate associated with the oblique Impingement of an axisymmetric jet are of interest as a result of its presence in numerous technological Problems. For the computation of heat transfer rate, the standard ${\kappa}-{\varepsilon}$ and ${\kappa}-{\varepsilon}-\bar {{\upsilon}'^ 2}$ turbulent model were adapted. The accuracy of the numerical calculations was compared with various experimental data reported in the literature. ${\kappa}-{\varepsilon}-\bar {{\upsilon}'^ 2}$ model showed better agreement with experimental data than standard ${\kappa}-{\varepsilon}$ model in prediction of the turbulent intensity and the heat transfer rate. In the case of computation of flowfield, the study carries on the ${\alpha}=45$ deg, h/D=4.95. The jet Reynolds number based on the nozzle diameter(D), was 48,000. For the computation of heat transfer rate, the Re=20,000, the jet orifice-to-plate spacings(L/D) are 4, 6 and 10, and the angle between the axis of the jet orifice and the plate surface is set at 30, 45, 60, or 90 deg. For the smaller spacings, the near-peak Nusselt numbers are not significantly effected by the initial decreases in the Jet angle. The overall shape of the local Nusselt number x-axis profile is influenced by both the jet orifice-to-plate spacing and the jet angle.