• 반도체디스플레이기술학회지
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• 제22권1호
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• pp.23-27
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• 2023

Organic light-emitting diode(OLED) is very thin organic films which are hundreds of nanometers. Unlike bottom-emission OLED(BEOLED), top-emission OLED(TEOLED) emits light out the front, opaque moisture absorbents or metal foils can't be used to prevent moisture and oxygen. And it is difficult to have flexible characteristics with glass encapsulation, so thin film encapsulation which can compensate for those two disadvantages is mainly used. In this study, Al₂O₃ thin films by atomic layer deposition(ALD) were examined by changing the argon gas purge flow rate and we applied this Al₂O₃ thin films to the encapsulation of TEOLED. Ag / ITO / N,N'-Di-[(1-naphthyl)-N,N'-diphenyl]-1,1'-biphenyl-4,4'-diamine / tris-(8-hydroxyquinoline) aluminum/ LiF / Mg:Ag (1:9) were used to fabricate OLED device. The characteristics such as brightness, current density, and power efficiency are compared. And it was confirmed that with a thickness of 40 nm Al₂O₃ thin film encapsulation process did not affect OLED properties. And it was enough to maintain a proper OLED operation for about 9 hours.

• Food Science and Biotechnology
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• 제15권3호
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• pp.431-436
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• 2006

Effects of vacuum packaging and modified atmosphere packaging (MAP) on shelf life of selenium-supplemented chicken meat during refrigerated storage were examined. Body weight and feed efficiency were unaffected by dietary selenium level. Dietary treatments and packaging methods had no significant effects on level of microbial growth, lightness, and metmyoglobin content. MAP decreased purge loss (10.9-34.5%) and lipid oxidation (15.2-15.9%) more efficiently than vacuum packaging. Broiler chicks supplemented with ${\alpha}$-tocopherol or ${\alpha}$-tocopherol + selenium had similar TBA values. Dietary supplementation of 4 and 8 ppm selenium reduced lipid oxidation, and this effect was less significant in MAP breast meat.

• 한국식품영양과학회지
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• 제31권4호
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• pp.604-608
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• 2002

염소를 함유한 알콜류의 추출 및 분석은 일반적인 알콜류에 비해 비등점이 높아 휘발 또는 증류법을 적용하기 어렵고 특히 히드록시프로필치환전분 중 PCH의 추출은 전분입자와의 에멀션을 형성하므로 어려움이 있다. 따라서 용매를 가온, 가압하여 추출효율을 높이고, 전분의 물성적인 특성으로 인한 여과의 어려움을 해소할 수 있는 가속용매추출기 (ASE)를 사용하여 PCH 분석을 하였다. 온도 40~15$0^{\circ}C$의 변화에 따른 회수율을 측정한 결과 온도 상승에 따라 회수율이 증가하는 경향을 나타내어 12$0^{\circ}C$에서는 96.1%의 회수율을 나타내었다. 압력 변화에 따른 추출효율을 검토한 결과 1500 psi까지는 압력 상승에 따른 회수율의 증가가 뚜렷하여 93.6%였으나 이후에는 완만하게 증가하여 2500 psi에서는 96.1%로 나타났다. 추출용매(초산에틸, 메탄올, 아세톤, 디에틸에테르 및 핵산)에 따른 PCH의 회수율을 측정한 결과 아세톤, 디에틸에테르, 초산에틸은 94% 이상의 회수율을 나타내었고 메탄올 87.3%, 핵산 14.1%로 나타났다. RSD(%)는 초산에틸이 5.6%로 가장 우수하였다. ASE를 이용한 히드록시프로필치환 전분 중 PCH의 최적 추출조건은 온도, 12$0^{\circ}C$; 압력, 2500 psi; 추출용매, 초산에틸, static time, 50분; purge time, 300초; heating time, 5분; flush(%), 100 mL였으며, 이때 회수율은 96.1%이었다.

• Carbon letters
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• 제2권1호
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• pp.44-54
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• 2001

The characteristics of adsorption and desorption of benzene and toluene were investigated at a fixed bed packed with the activated carbon and activated carbon fiber. Through breakthrough experiments under various feed concentration conditions, it was found that the slope of mass transfer zone and the tailing in the breakthrough curves were different from the feed conditions due to different heats of adsorption. In hot nitrogen desorption, the regeneration time and mass transfer zone of the toluene desorption curve were longer than those of the benzene desorption curve because of the difference in adsorption affinity. With an increase in the regeneration temperature, the height of roll-up and the sharpness of desorption curves increased but the regeneration times decreased. The adsorption capacities of the activated carbon and activated carbon fiber after three-time thermal regenerations decreased about 25% and 37% for benzene and 18% and 25% for toluene, respectively. To investigate the effect of the regeneration temperature on the energetic efficiency, the characteristic desorption temperatures of toluene and benzene were investigated by calculating purge gas consumption and temperature.

• Food Science and Biotechnology
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• 제15권2호
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• pp.248-253
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• 2006

This study examined the effects of vacuum packaging and modified atmosphere packaging (MAP) on the meat quality of ${\alpha}$-tocopherol supplemented broiler chicks after prolonged refrigeration. The supplemented ${\alpha}$-tocopherol levels had no effect on the body weight and feed efficiency. The dietary treatments and packaging methods had no significant effects on the level of microbial growth, lightness, and the metmyoglobin content. The vacuum packaging showed the highest level of purge loss. The broilers supplemented with either 200 or 400 IU of ${\alpha}$-tocopherol had a lower level of malondialdehyde than the control group. The vacuum packaged meats from chicks fed the control diet showed the highest levels of lipid oxidation. The lipid oxidative stability was most improved in modified atmosphere (20% $CO_2$ + 80% $N_2$) packaged breast meat from the broilers supplemented with either 200 or 400 IU of ${\alpha}$-tocopheryl acetate.

• 설비공학논문집
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• 제26권1호
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• pp.26-31
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• 2014

This study looks into changing building energy use by application of phase change material (PCM). PCM does not need extra energy for operation and is used for reducing building energy use and, CO2 output by displaying semi-permanent effects after installation. It also is able to avoid the maximum electric power time-zone by inducing a time lag phenomenon of cooling and heating loads with high thermal capacity using latent heat. To verify the efficiency of blinds and PCM, tests about the PCM operation mechanism using air conditioning machinery and nocturnal panel cooling were done. In the test results of the case using PCM installation, a $45^{\circ}$ blind angle with machinery air conditioning and nocturnal panel cooling at the same time shows a 22 percent energy saving effect against general space. The test results of each case were compared and analyzed based on the blind and window opening settings. Finally, the energy reduction of existing buildings using PCM application was reviewed based on the final measurement results.

• Applied Biological Chemistry
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• 제47권2호
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• pp.228-237
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• 2004

농약성분 분석에 있어서 시료 전처리시간을 단축할 수 있는 분석방법을 개발하기 위해 농산물 중에 잔류하고 있는 잔류농약성분을 대상으로 ASE(accelerated solvent extraction) 방법을 활용한 자동화된 전처리 방법을 검토하였다. ASE 추출조건은 preheat 1 min, heat 5 min, static 1 min, solvent flush% 60 vol, nitrogen purge 60 sec, cycle 4, pressure 1500 psi, temperature $100^{\circ}C$를 선택하였다. 이 분석조건과 n-hexane:acetone(4 : 1, v/v)를 추출용매로 사용하였을 때, ASE 추출과 정제능력은 solvent extraction 방법과 유의적인 차이를 보이지 않았고, 추출 용매의 감소는 추출산물의 재현성에 큰 영향을 미치지 않았다. ASE 방법은 잔류농약 분석 시 소요되는 유기용매의 양을 감소하고 추출과 정제를 동시에 수행함으로써 동결건조 시간을 제외한 전처리 시간이 단축되어 분석비용 또한 solvent extraction에 비해 감소시킬 수 있었다.

• 한국수소및신에너지학회논문집
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• 제23권3호
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• pp.250-255
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• 2012

In this paper, the development and performance analysis of a fuel cell-powered unmanned aerial vehicle is described. A fuel cell system featuring 1 kW proton exchange membrane fuel cell combined with a highly pressurized fuel supply system is proposed. For the higher fuel consumption efficiency and simplification of overall system, dead-end type operation is chosen and each individual system such as purge system, fuel supply system, cooling system is developed. Considering that fluctuation of exterior load makes it hard to stabilize fuel cell performance, the power management system is designed using a fuel cell and lithium-ion battery hybrid system. After integration of individual system, the performance of unmanned aerial vehicle is analyzed using data from flight and laboratory test. In the result, overall system was properly operated but for more duration of flight, research on weight lighting and improvement of fuel efficiency is needed to be progressed.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.567-571
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• 2008

PEM Fuel Cell operation mode can be classified into dead-end mode or open mode by whether the outlet port is blocked or not. Generally, dead-end type fuel cell has some merits on the pressure drop and system efficiency because it can generate more power than the open type fuel cell due to high operating pressure condition. However, the periodic purging process should be done for removing water which is formed as product of a reaction in the gas diffusion layer. In this study, cathode side dead-end type operation has been conducted. Moreover, pulsating flow generator at the outlet of cathode side has been suggested for increasing the period to purge the formed water because the pulsating flow can make formed water scattered uniformly over the whole channel. As a result, the purging period with pulsation increased by 1.5-2 times longer than that without pulsating.

• 대한환경공학회지
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• 제39권8호
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• pp.462-469
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• 2017

최근 부영양화 문제, 인광석 자원이 부족해지고 있는 국제적 상황, 하수처리장 관로 스케일 문제 등에 대응하기 위하여, Struvite 결정화 공정을 하수처리장 슬러지처리 계통의 고농도 인 제거/회수에 적용하려는 시도를 하고 있다. 본 연구는 실제 국내 하수처리장 슬러지처리 계통에 대한 Struvite 결정화 공정 적용 가능성을 평가를 목표하여, 첫째, 운영자료 및 현장측정자료 분석을 통하여 실제 하수처리장 슬러지처리 계통의 인 농도 및 물질수지를 분석하였고, 둘째, 평형화학 계산 프로그램을 활용하여 Struvite 결정화 반응 포텐셜, 이에 따른 최적 $Mg^{2+}$ 주입량, pH 등에 관해 연구하였고, 셋째, 실험실규모 배치실험을 통해 실제 Struvite 결정화 반응 동역학에 대해 연구하였다. 슬러지처리 계통에서의 인 농도 및 물질수지를 분석하였을 때, Struvite 결정화 공정은 소화슬러지 및 탈리여액에 적용함이 바람직한 것으로 파악되었다. 평형화학 계산결과, 안정적인 공정 운영을 위해서는 pH 8 이상, $Mg^{2+}$ 주입량은 몰비 기준 이론 요구량의 1.2배 이상을 첨가해야 하는 것으로 파악하였다. 그리고, Struvite 결정화 반응 동역학은 1차 반응속도식을 따르고, Struvite 결정화 반응이 평형상태에 도달한 경우, 모든 pH 조건에서 인산염인 제거율이 80% 이상으로 우수하게 나타났다. Struvite 결정화 반응 시 NaOH 첨가 없이 폭기만으로 $CO_2$ 탈기를 일으켜 반응 종결 후 pH 8.7 이상까지 상승했으며, $Mg^{2+}$ 주입원의 경우 간수 등 저가 대체물질을 활용할 수 있으므로, 약품비에 의한 운영비 증대 없이 Struvite 결정화 공정을 적용할 수 있으리라 판단된다.