• Korean Journal of Food Science and Technology
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• v.26 no.1
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• pp.18-22
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• 1994

This study was designed to investigate the method of the simultaneous determination of water-soluble vitamins (thiamine, ascorbic acid, riboflavin, folic acid, cyanocobalamine, pyridoxin, nicotinic acid) by free soloution capillary electrophoresis. Factors affecting on the separation were pH of the buffer, applied voltage and temperature. On-column detection at 254 nm allowed accurate and reproducible determination of these compounds. All these compounds were separated within ca. 8 min with fused silica capillary at 20 kV.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.91.2-91.2
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• 2010

SOFC는 높은 반응온도($600{\sim}1000^{\circ}C$)에서 작동되어 발전효율이 높고 다양한 연료를 사용할 수 있는 것이 장점이다. 하지만 고온에서의 운전은 구성요소의 열변형과 온도구배에 의한 전극촉매의 열화 그리고 밀봉재의 수명에 영향을 주어 결국 스택의 내구성을 감소시킨다. 특히 스택의 온도구배가 심화되면 국부적인 Hot spot를 형성하여 셀에 심각한 손상을 주게 된다. 본 과제에서는 SOFC 스택의 온도구배를 완화시키기 위한 내부개질기의 개발 및 고온용 분리판 소재의 정밀성형기술을 확보하고자 한다. 열/유동해석을 통하여 반응가스의 농도, 유속, 구조변경 등 내부개질기 온도구배에 대한 주요인자를 확인하였고, 장기 운전평가를 통하여 개질 촉매의 고온 활성 및 내구성에 대한 성능평가를 진행 중이다. 분리판의 경우, 고온용 소재(페라이트계 스테인레스)에 대한 기초실험을 실시하여 성형품질의 주요 인자를 파악하였으며 Proto-type 금형 설계 및 개발을 통하여 성형 기초기술을 확보하였다. 그리고 스택 내부온도를 구현할 수 있는 시뮬레이터를 설계 중에 있으며 이를 이용하여 개발된 내부개질기 및 분리판을 스택 운전환경에서 평가할 예정이다.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.687-690
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• 2009

고압의 가스를 이용하여 고온 가스와 저온 가스를 분리하거나 입자상 물질의 분리에 사용할 수 있는 장치인 볼텍스 튜브의 에너지 분리 특성을 파악하기 위하여 $20Nm^3$/hr급 볼텍스 튜브를 제작하고 이에 대한 실험을 진행하였다. 입구 압력, 저온측의 유량비가 온도에 미치는 영향을 분석하였다. 입구 압력이 높아질수록 고온측의 온도는 증가하고, 저온측의 온도는 강하하였다. 저온 유량비 80%를 전후하여 고온측 온도가 최고점을 나타냈고, 저온유량비 40%를 전후하여 저온측 온도가 최저점을 나타냈다.

• Resources Recycling
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• v.7 no.5
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• pp.26-32
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• 1998

Recycline of used plastics is rather restricted due to their variety and difficulties in their separation. In this study, a reliable and economical method for the separation of PVC which utilizes an appropriate control of surface chemistry of pariticles was suggested. this method consists of modification of PET surface from hydrophobic to hydrophilic by NaOH solution and subsequent separation by a froth flotation technique. Flotation results were in terms of NaOH concentration, digestion temperature and time, temperature and pH of solution, PVC concentration. They could be separated up to 95~100% by this method.

• Membrane Journal
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• v.2 no.2
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• pp.135-143
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• 1992

Separation of $N_2-SO_2$ mixed gas by polymer membranes, SEPA-97(CA), TFC, and FT-30 membrane, was investigated by varying pressure and temperature. The permeability coefficients and the separation factors of mixed gases were measured, and the influence of various factors on the gas permeability characteristics and separation performance were investigated. The range of pressure was 0.1~1.0 MPa, and that of temperature was 283~303 K. The experimental results showed that the permeability coefficients and the separation factors were increased with an increase in pressure, but they were deereased with increasing temperature. Among the examined membranes, FT-30 possessed the best gas-separating characteristics.

• Korean Journal of Optics and Photonics
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• v.8 no.6
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• pp.461-465
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• 1997

The 3rd order nonlinear optical susceptibility was measured through the self-induced ellipse rotation. The phase separation temperature increases with the increase of salt and it decreases with the increase of glycerol.

• Journal of the Korean Chemical Society
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• v.33 no.6
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• pp.601-606
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• 1989

The effects of temperature and retaining ion on the separation factor (${\alpha}$) and distribution ratio (D) of some lanthanides ($Pr^{3+},\;Nd^{3+},\;Sm^{3+},\;and\;Er^{3+}$) have been studied in the EDTA solution as an elutant by using Amberite IR 120 + resin. The retaining ions on the resin were ${NH_4}^+,\;Na^+,\;K^+,\;Mg^{2+},\;Ca^{2+},\;Zn^{2+}$and $Ce^{3+}$. Separation factor of Nd/Pr is much improved by using $Ce^{3+}$ as retaining ion. The distribution ratios were decreased with the increase of temperature, but separation factors did not always increase with the increase of temperature. However, in the case of $Ce^{3+}$ as retaining ion, separation factors of Nd/Pr and Sm/Nd were increased with the increasing of temperature. And also in the case of $Zn^{2+}$ as retaining ion, separation factor of Er/Sm was increased with the increasing of temperature.

• Korean Chemical Engineering Research
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• v.44 no.1
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• pp.35-39
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• 2006

This study was performed to understand temperature effect on retention behavior of fructose and glucose as sugars and lactic acid and acetic acid as organic acids on poly (4-vinylpyridine) resin. The pulse tests were performed to understand temperature effect on retention time of sugars and the results were not shown large change. As it was able to predict with PVP resin not to be used for sugar separation generally, the results were shown poor resolution for separation of sugars and temperature effect on the resolution change of sugars also was not large. On the other hand, in the case of organic acids on PVP resin, the pulse tests were shown temperature effect on the retention behavior was very large. So, the frontal analyses were performed to understand quantitative adsorption behavior of organic acids at 35 and $65^{\circ}C$. These adsorption characteristics of organic acids with PVP resin system can be used to preparative chromatographic process such as SMB (simulated moving bed).

• Journal of the KSME
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• v.56 no.1
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• pp.32-35
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• 2016

이 글에서는 최근 수요가 증가하고 있는 질소, 산소 등의 산업용 가스 생산, 분리용 극저온 공기 분리플랜트 기술에 대해서 소개하고자 한다.

• Journal of Energy Engineering
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• v.13 no.1
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• pp.34-39
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• 2004

The process of energy separation in a low pressure vortex tube with compressed air as a working medium is studied in detail. Experimental data of the temperature of the cold and hot air leaving the vortex tube are presented. The variation of the maximum wall temperature along the inner surface of a vortex tube and the temperature distribution in a vortex tube provide useful information about the location of the stagnation point of the flow field at the axis of the vortex tube Analysis of the results enabled to find the optimum ratio of nozzle area and the optimum shape of an orifice. From this optimum geometric setup of a low pressure and big vortex tube the effectiveness of energy separation was better than a high pressure and small vortex tube.