• Korean Journal of Fisheries and Aquatic Sciences
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• v.6 no.3_4
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• pp.97-100
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• 1973

In the previous work(Kim et al, 1973), the quality of sun-dried Alaska pollack, Theragra chalch-ogramma, was discussed in the aspect of non-enzymatic discoloration as a function of relative humidity during storage at room temperature($20^{\circ}C$). In this paper, sun-dried squid, Ommastrephes steam pacificus was investigated at the same aspect mentioned above. Fresh squid from the whole sale market was dressed, filleted, dried for 48 hours in the open air and finally stored in the humidistat chamber. Lipid oxidation ana development of non-enzymatic browning were tested by the same methods described in the previous paper. The TBA value showed a maximum peak on 30 day storage, hereafter tended to decrease gradually. The rate of browning, however, in water soluble fraction as well as in chloroform-methanol fraction was lower at 0.34 to 0.45 water activity than at any other case, and propagation of lipid oxidation was also diminished at the above level of water activity. From the results, it is recognized that storage at Aw=0.34 to 0.45 provides higher quality stability for sun-dried squid.

• Journal of Hydrogen and New Energy
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• v.18 no.2
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• pp.132-139
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• 2007

Popular techniques for producing synthesis gas by converting methane include steam reforming and catalyst reforming. However, these are high temperature and high pressure processes limited by equipment, cost and difficulty of operation. Low temperature plasma is projected to be a technique that can be used to produce high concentration hydrogen from methane. It is suitable for miniaturization and for application in other technologies. In this research, the effect of changing each of the following variables was studied using an AC Glidarc system that was conceived by the research team: the gas components ratio, the gas flow rate, the catalyst reactor temperature and voltage. Glidarc plasma reformer was consisted of 3 electrodes and an AC power source. And air was added for the partial oxidation reaction of methane. The result showed that as the gas flow rate, the catalyst reactor temperature and the electric power increased, the methane conversion rate and the hydrogen concentration also increased. With $O_2/C$ ratio of 0.45, input flow rate of 4.9 l/min and power supply of 1 kW as the reference condition, the methane conversion rate, the high hydrogen selectivity and the reformer energy density were 69.2%, 36.2% and 35.2% respectively.

• Journal of the Korean institute of surface engineering
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• v.34 no.6
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• pp.585-591
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• 2001

니오비움 첨가 지르코늄 합금(Zr-1%Nb)의 고온 수증기에서 산화속도에 관한 연구를 수행하였다. 산화온도는 $700-1200^{\circ}C$이다. 대기압수증기에서 산화될 때, Zr -1%Nb은 2차법칙을 따르는 것으로 나타났으며, 이는 $900^{\circ}C$이하에서 3차법칙을 따르는 지 르칼로이 -4와 상이한 형태를 보이고 있다. $900^{\circ}C$이상에선 산화속도가 지르칼로이 -4보다 약간 낮으며, 산화후 금속층의 경도가 증가하였다. 경도증가로 보아 인성의 감소가 예상되며, 따라서 니오비움 첨가 지르코늄 합금의 사고시 안전성에 대한 주의가 요구된다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.225-229
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• 2005

We have designed micro-fuel processor system, which consists of a steam reforming area and a PROX(preferential oxidation) area. Micro-fuel processor system generates $H_2$ rich gas from a methanol. In our experiment, we have integrated micro-fuel processor system using low temperature cofired ceramics (LTCC) process because LTCC is superior to other materials principally due to their high thermal and chemical stability, simpler fabrication processes, and lower materials cost. Therefore, we have studied and integrated micro-fuel processor system containing embedded heaters, cavities, and 3D structures of micro-channel with LTCC. Also we have optimized the LTCC process.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.101-102
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• 2014

수소제조용 SMR(steam methane reforming) 공정에 사용될 수 있는 FeCrAl 다공체의 지지체-촉매의 결합력을 향상시키기 위하여 PEO(plasma electrolytic oxidation)법을 이용하여 FeCrAl 표면에 산화물을 형성시켰다. 열처리, 저전압, 고전압, 전해질 농도 등의 공정 조건에 따른 산화막의 형성 거동 및 형성된 산화물의 상분석 등을 진행하였다. PEO 공정을 이용하여 형성된 산화막은 다른 공정에 의하여 형성된 산화막과 비교할 때 치밀한 특징을 보였다. 따라서 본 연구를 통하여 향후 SMR 공정에 사용될 수 있는 FeCrAl 다공체의 내구성 및 수명 향상에 도움을 줄 것으로 기대되었다.

• Journal of the Korean Ceramic Society
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• v.23 no.4
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• pp.55-61
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• 1986

Phosphosilicate glass(PSG) films have been used as fusable deposited dielectrics in silicon gate MOS integrated circuits. But in this experiment BPSG(borophosphosilicate glass) will be optimized for more efficient utilization of the reactants. The BPSG films were deposited on silicon wafers by the oxidation of the hydrides at 430$^{\circ}$C in conventional atmospheric-pressure chemical-vapor-deposition (CVD) systems. Physical and chemical properties of CVD BPSG films have been characterized both for as-deposited and for fused films The. relationship between deposited BPSG film composition and infra-red absorption solution etch rate and fusion temperature is discussed and examples of BPSG composition that can be fused at 900~95$0^{\circ}C$ and 800~85$0^{\circ}C$ are given. In addition to having lower fusion temperature than PSG films BPSG films have lower as-deposited intrinsic tensile stress and low aqueous chemical etch rate they have been considered for applications where these characteristics are advantageous.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.97-97
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• 2015

전 세계적으로 화석연료의 고갈 및 환경오염 문제를 해결하기 위해 신재생에너지에 대한 관심이 급증하고 있다. 이러한 신재생에너지에는 수소 에너지, 자연 에너지(태양열, 지열 등), 바이오 매스 에너지 등이 포함된다. 이 중 수소 에너지는 지구상에 풍부하게 존재하고 있는 물과 탄화수소로부터 얻어지며, 연소 시에도 다시 물을 형성하여 오염 물질을 배출하지 않는 차세대 무공해 에너지원으로써 주목을 받고 있다. 수소 제조를 위한 공정에는 수증기 개질 공정(steam reforming), 부분 산화(partial oxidation) 및 자열개질(autothermal reforming) 등이 있으며 실제로 생산되는 대부분의 수소는 탄소/수소비(1:4)가 높은 메탄($CH_4$) 가스를 이용한 메탄 수증기 개질 공정(steam methane reforming)을 통하여 제조된다. 이 때 수소 제조의 고효율화 및 저비용화를 위해서는 반응물에 대한 높은 선택도, 고활성도 및 높은 안정성을 갖는 촉매가 반드시 필요하며, 대표적으로 Ni, Pt, Ru 등이 보고되고 있다. 이러한 촉매들은 대부분 세라믹 pellet 형태로 제작되어 왔으나 열전도도가 낮고 물리적 충격에 취약하다는 단점이 존재한다. 따라서 우리는 이러한 단점을 극복하고, 촉매의 활성을 높이기 위하여 다공성 금속 합금 폼을 촉매 지지체로 도입하였다. 또한, 다공성 금속 합금 폼 표면에 촉매의 분산 및 안정성을 향상시키기 위해 지지체와 촉매 사이에 원자층 증착법을 이용하여 inter-layer를 도입하였다. 이들의 구조, 형태, 및 표면의 화학적 상태는 주사전자현미경, EDS (energy dispersive spectroscopy)가 탑재된 주사전자현미경, X-선 회절, 및 X-선 광전자 분광법을 이용하여 규명하였다. 더하여 정전압-전류 측정법 및 유도 결합 플라즈마 분광 분석기을 이용하여 전기 화학 반응을 유도하고, 반응 후 전해질의 성분분석을 통해 촉매와 지지체 간의 안정성을 평가하였다. 따라서 본 결과들은 한국진공학회 하계정기학술대회를 통해 좀 더 자세히 논의될 것이다.

• The Korean Journal of Food And Nutrition
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• v.11 no.3
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• pp.272-277
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• 1998

We carried out separation and guantitation of flavor components by GC about essential oils extracted from deodorized corn oil at the different deodorizing temperature. Flavor components were detected total 16 kinds included aldehydes of 8 kinds, major components were propane, pentane, hexanal etc. These major components content was about 70~75% of the total flavor components. According to rise of deodorizing temperature, both ethane and aldehydes of 8 kinds content were in proportion to increase, but propane, pentane, hexane, octan, pentyl furan content were decreased by contraries, respectively. On the other hand, total flavor component content was appeared the lowest level at 245$^{\circ}C$ treating group, aldehydes content was in proportion to increase according to rise of deodorizing temperature. These phenomenons consider that the undesirable reactions such as partial auto-oxidation, degradation, polymerization and hydrolysis etc. by effecting factors of stripping steam and vacuum degree. Conclusively, deodorizing temperature under high temperature was undesirable for the minimization of off-flavor materials.

• Bulletin of the Korean Chemical Society
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• v.25 no.5
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• pp.681-686
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• 2004

Ti-ZSM-5 prepared by secondary synthesis, from the reaction of H-ZSM-5 with vapor phase $TiCl_4$, was characterized with several physicochemical techniques including FT-IR and UV/VIS-DRS. It was found that zeolite structure, surface area and pore volume did not change, and the framework aluminum could not be replaced by titanium atom during the secondary synthesis of Ti-ZSM-5. The incorporation of titanium into the framework might be due to reaction of $TiCl_4$with the silanol groups associated with defects or surface sites. The formation of extra-framework titanium could not be avoided, unless the samples were further treated by water vapor at 550 $^{\circ}C$ or higher temperature. High temperature steam treatment of Ti-ZSM-5 prepared by chemical vapor deposition with $TiCl_4$was efficient to prevent the formation of non-framework titanium species. Ti-ZSM-5 zeolites prepared in this work contained only framework titanium species and exhibited improved catalytic property close to TS-1 prepared by hydrothermal synthesis.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.353-358
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• 2003

Volatile compounds of porcine liver were collected by simultaneous steam distillation and extraction and steam distillation under reduced pressure. Volatiles were analyzed by gas chromatography (GC) and GC-mass spectrometry. Key aroma compounds of off-flavor in porcine liver were characterized using GC-olfactometry technique. Concentrates of cooked porcine liver had odor of a typical liver, fishy, and metallic off-flavor. Aroma concentrates showed over 90 peaks, of which 69 compounds were positively and/or tentatively identified. 1-Octen-3-one, 1-hexanol, (E)-2-nonenal, (Z)-4-decenal, (E,E)-2,4-heptadienal and (E,E)-2,4-decadienal were newly identified in this study. These compounds seem to be produced from unsaturated fatty acids of porcine liver by oxidation. 1-Octen-3-one (metallic), 1-hexanol (metallic) and (E,E)-2,4-heptadienal(fishy) have been implicated in fishy and metallic off-flavor in cooked porcine liver.