• 한국연소학회:학술대회논문집
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• 한국연소학회 2002년도 제25회 KOSCI SYMPOSIUM 논문집
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• pp.65-69
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• 2002

Catalytic combustion known as one of the traditional oxidation methods of VOC gas is restricted to its applicable fields because of its reaction characteristics. But recently innovative improvement of catalytic endurance makes its applicable range broader from MEMs to industrial power generation. Therefore, control technologies based on the catalytic combustion characteristics are researched and developed dynamically. Especially, the stable control of catalytic combustion is an essential factor in a view of maximizing its efficiency. In this research, the fuel equivalence ratio and the preheating temperature of mixture gas is controlled by catalytic combustion system enhanced in heat transfer with high temperature heat exchanger. As a result, the combustion characteristics of system was investigated, and both passive and active control type were compared and analyzed.

• 한국잠사곤충학회지
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• 제49권2호
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• pp.47-50
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• 2007

누에 체액은 공기 중의 산소와 접하게 되면 도파퀴논(dopaquinone)이라는 세포 성장을 저해하는 물질을 생성하게 된다. 체액의 산화를 방지하기 위해서는 일반적으로 열처리에 의해서 효소를 불활성화 시키는 방법이 이용되고 있으나 대량 채혈 시에는 열처리 이전에 이미 산화가 진행되는 문제점이 있다. 이러한 문제점을 해결하기 위하여 누에 중 체액 산화가 더디게 진행되는 누에 계통을 선발하게 되었다. 누에체액을 채취하여 경과시간별로 산화정도(변색)를 육안으로 확인하여 TBO, $Y_4$, 백안$E^b$과잉지 3품종을 선발하고 spectrophotometer를 이용하여 산화반응 속도를 측정하였다. 백옥잠 체액과 각각의 산화지연 누에 체액의 산화속도를 400 nm에서 측정한 결과 백옥잠은 120분인데 비하여 체액산화 지연계통인 $Y_4$는 330분, TBO는 360분 그리고 백안$E^b$과잉지는 450분에 산화가 완료되었다. 산화지연 누에계통의 체액의 곤충세포 증식에 미치는 영향을 조사한 결과 대규모 채혈한 체액산화지연 계통의 체액은 야성형 계통(백옥잠)에서 소규모 채취한 체액에는 미치지 못하였으나 대규모 채취한 체액보다는 우수하였다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.249-251
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• 2014

Synthesis gas such as hydrogen and carbon monoxide was produced from $CH_4//oxygen$ mixture using two-section porous media combustor. Heat recirculation through the inner foam structure could extend the flow velocity of stable region over the laminar burning velocity. $H_2/CO$ ratio and module M from concentration of flue gas measured by Gas Chromatography was similar to those calculated by equilibrium. But it was made sure that the heat loss effect becomes more influential than heat recirculation effect as the mixture gets richer. To generate synthesis gas appropriate for methanol production, insulated pressurized porous media combustor will be designed and built in the future.

• 대한금속재료학회지
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• 제49권1호
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• pp.17-24
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• 2011

To investigate the relationship between heat treatment in zirconium alloy tubing process and metallurgical characteristics of Zr-1Nb-0.69Sn-0.11Fe alloy tubes, mechanical and oxidation behaviors of tubes heat treated at different temperatures after the final pilgering were investigated. The stress strain curves exhibited the saturation behaviors in all heat treatment conditions ($460{\sim}600^{\circ}C$) in this study with the onset strain of saturation increased with increase of post-pilgering annealing temperature. The strength fell off rapidly with increasing annealing temperature. The ultimate strength of the low tin Zr-1Nb-0.69Sn-0.11Fe alloy with slightly higher iron and oxygen contents in this study was found to be higher than Zr-1Nb-1Sn-0.1Fe alloy. The oxidation experiments in steam condition revealed that the corrosion resistance of low tin Zr-1Nb-0.69Sn-0.11Fe alloy was better than the Zr-1Nb-1Sn-0.1Fe alloy with a higher Sn content. The weight gain of low tin Zr-1Nb-0.69Sn-0.11Fe alloy tubes gradually increased with the increasing annealing temperature possibly due to the decreased Nb content in the matrix because of the formation of ${\beta}-Nb$ particles.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2006년도 춘계학술발표회 초록집
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• pp.90-90
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• 2006

• Nuclear Engineering and Technology
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• 제33권3호
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• pp.307-314
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• 2001

The changes of weight gain, structure, morphology and uranium oxidation states in l0wt% G $d_2$ $O_3$-doped U $O_2$ during the oxidation below 475$^{\circ}C$ and heat treatment at 130$0^{\circ}C$ in air were investigated using TGA, XRD, SEM, EPMA and XPS. The room temperature ( $U_{0.86}$G $d_{0.14}$) $O_2$Cubic Phase Converted to highly distorted ( $U_{0.86}$G $d_{0.14}$)$_3$ $O_{8}$ -type sing1e Phase by oxidation at 475 $^{\circ}C$ in air. This oxidized phase was reduced by annealing at 130$0^{\circ}C$ in air. The room temperature XRD pattern of the 130$0^{\circ}C$ annealed powder revealed that ( $U_{0.86}$G $d_{0.14}$)$_3$ $O_{8}$ -type single phase was separated into Gd-depleted $U_3$ $O_{8}$ and Gd-enriched ( $U_{0.7}$G $d_{0.3}$) $O_2$$_{+x}$ type cubic phase. The reduction and phase separation by the high temperature annealing of kinetically metastable and highly deformed ( $U_{0.86}$G $d_{0.14}$)$_3$ $O_{8}$ -type phase are interpreted in terms of cation size difference between G $d^3$$^{+}$ and U according to the oxidation state of U.U.U.U.U.te of U.U.U.U.U.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.172.2-172.2
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• 2010

This study was carried out in order to reduce the installation expense of heating system for greenhouse comparing to geothermal heat pump and develope the coefficient of performance (COP) for a heat pump. For getting plenty of heat flux from geothermal energy. Surface water in river channel was used for getting a lots of geothermal heat by penetrating water through underground soil layer of the river bank that make heat transmission to passing water. The range of water temperature after the process of Ground filtration is 13~18 degrees celsius which is very similar to low heat source of geothermal heat pump system and the plenty amount of heat source from that make the number of geothermal heat exchanging hole and the expense for geothermal heat exchanger construction reduced. Drainage well is also used for returning filtration water to the aquifer that keep the water good recirculation from losing geothermal heat and water resource. For the COP improvement of Heat pump, thermal storage tank with separating insulation plate according to the temperature difference make the COP of Heat pump that is similar to thermal storage tank with diffuser. Developed thermal storage tank make construction expense cheaper than customarily used one's. and that sand filter and oxidation sand (FELOX) are going to be used for improving ground filtration water quality that make heat exchanger efficiency better. All above developed component skill are going to be set on the Ground filtration water source heat pump system and applied for medium, large scale for protected greenhouse in riverside area and on-site experiment is going to do for optimizing the heating system function and overcome the problem happening in the process of on-site application afterward.

• 화약ㆍ발파
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• 제18권1호
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• pp.53-58
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• 2000

Thermal analysis, analysis of combustion residue and combustion characteristics measure ment such as burning rate or temperature were carried out to clarify the combustion mechanism of a tungsten- potassium perchlorate-barium chromate chromate delay powder. The results obtained are as follows. The main reaction of the delay powder of tungsten-potassium perchlorate-barium chromate is the oxidation of tungsten by potassium perchlorate. Barium chromate acts as a burning rate modifier, and the smaller the larger is the burning rate. Three types of delay composition used in this study show characteristic burning behavior. A stoichiomertric or a oxidizer-rich composition has a small linear burning rate. although it is has a large heat of combustion. On the other hand, a tungsten-excess or a fuel-rich composition with a small heat of combustion has a larger linear burning rate than the former, showing a small fractional oxidation of tungeten (below 10%) contained in the delay powder. From these results, a surface combustion mechanism is proposed for the combustion mechanism of this delay powder.

• 한국축산식품학회지
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• 제38권3호
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• pp.530-543
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• 2018

This study investigated the effect of yellow, black, and brown mustard seeds on color, lipid oxidation (thiobarbituric acid-reactive substances [TBARS]), and microbiological and sensory qualities of meatballs during storage. Heat treatment of mustard seeds affected the TBARS value of meatball samples (p<0.0001). The addition of mustard seeds decreased TBARS value of meatball samples (p<0.0001). Heat treatment of mustard seeds decreased the $L^*$, $a^*$ and $b^*$ values of meatball samples (p<0.0001). The meatball samples with mustard seeds increased $b^*$ value of meatball samples however it decreased $a^*$ value of meatball samples (p<0.0001). The addition of mustard seeds decreased aerobic mesophilic bacteria count (p<0.0001), Enterobacteriaceae count (p<0.0001), psychrophilic bacteria count (p<0.0001) and yeast and mold count of meatball samples (p<0.0001). On a given storage day, the yellow mustard added meatballs sample was given higher color, appearance, flavor, acceptability ratings than those added black and brown mustard. Regarding sensory and microbiological properties, mustard seed contributed to microbiological quality and sensorial properties of meatball samples.

• 한국축산식품학회지
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• 제39권2호
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• pp.296-308
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• 2019

Although the yellow mealworm (Tenebrio molitor L.) is a promising alternative protein source, the effects of processing conditions on functional properties are unclear. In this study, a protein extract of yellow mealworm larvae (PEYM) was subjected to different heat temperature ($55^{\circ}C$, $75^{\circ}C$, and $95^{\circ}C$) with different time (20, 40, and 60 min) to evaluate the functional properties and protein oxidation. Different heat temperature treatment significantly affected the exposure of surface hydrophobicity of the proteins and protein molecule aggregation, which reached maximum levels at $95^{\circ}C$ for 60 min. Protein oxidation was inversely proportional to the temperature. Both the highest carbonyl value (1.49 nmol/mg protein) and lowest thiol value (22.94 nmol/mg protein) were observed at $95^{\circ}C$ for 60 min. The heating time-temperature interaction affected several functional properties, including solubility, emulsifying potential, and gel strength (GS). Solubility decreased near the isoelectric point (pH 5 to 6). As the temperature and heating time increased, emulsifying properties decreased and GS increased. The oil absorption capacity and foaming properties decreased and the water absorption capacity increased. These results confirmed that PEYM is a suitable source of proteins for processing and applications in the food industry.