• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.10a
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• pp.384-387
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• 2004

겨울철 토양에서 ${\beta}-Galactosidase$를 생산하는 균주를 분리하였으며 동정한 결과 그람 음성 간균이고 Pantoea spp. 로 확인되었다. Pantoea spp. 균주의 세포 추출물로부터 DEAE-Sephacel chromatography와 affinity chromatography를 이용하여 ${\beta}-Galactosidase$를 분리하였다. Pantoea spp. 의 ${\beta}-Galactosidase$의 반응 최적 온도는 $45^{\circ}C$이이고 최적 pH는 $5.5{\sim}7.5$이고 열안정성을 조사한 결과 $45^{\circ}C$이상의 온도에서 불활성 되는 것으로 나타났고 E. coli에서 분리된 효소보다 저온에서의 활력이 좋았지만 상업적인 효소인 Kluyveromyces lactis (Validase) 보다는 낮았다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.224-225
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• 2015

폐솔더 박리액으로부터 주석 및 구리의 분리를 위하여 옥살레이트 침전을 통해 각각 금속염으로 회수하기 위한 기초 연구를 실시하였다. 먼저 옥살산의 첨가량에 따라 주석의 침전율이 증가하였으며 당량비(옥살산/주석)의 1.0-1.5배를 첨가할 경우 주석이 99.5%, 구리는 2.0% 정도 침전되었고 철, 납 등은 거의 침전되지 않아 주석만 선택적으로 침전되는 것을 확인 하였다. 반응온도 증가에 따라 주석의 침전율은 증가하여 $60^{\circ}C$ 부근에서 최대값을 보이다가 온도가 더 증가하면 오히려 감소 경향을 보였다. 침전물의 고액분리 용이를 위해 카티온성 고분자 응집제를 이용하여 침강시킨 후, 분리된 침전물을 건조, 분쇄하여 $SnO_2$의 산화물을 얻을 수 있었다. 주석이 제거된 폐솔더 박리액에 옥살산을 첨가하여 구리가 약 91% 이상 침전되어 납, 철 등의 금속과 분리하여 선택적으로 회수가 가능하였다.

• KSBB Journal
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• v.11 no.1
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• pp.46-51
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• 1996

Cell separation by means of continuous foam separation of Saccharomyes formosensis without additive was investigated. The yeast separation ratio was improved at low feed rates, high nitrogen rates, optimum pH and temperature for ethanol production, dilution of cultivation medium and addition of 0.5g/$\ell$ $CaCl_2$. Percentage of yeast removal and yeast separation ratio were more than 85 when continuous foam separation was operated in optimum condition..

• Korean Chemical Engineering Research
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• v.43 no.6
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• pp.704-714
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• 2005

Phase separations of Poly(4-vinylphenol)(PVPh)/Ethyl Acetate and PVPh/Butyl Acetate solutions were measured using the thermal optical analysis (TOA) method. The experimental phase separation data were correlated with liquid-liquid equilibria relations based on PC-SAFT equation of state. The phase separations of these system showed the behaviors of LCST (lower critical solution temperature)-type. The measured cloud temperatures were lowered with increasing in molecular weights of polymer(PVPh), and cloud temperatures of PVPh/Ethyl Acetate solutions shifted to lower temperature regions, compared to the PVPh/Butyl Acetate solutions. Extents of cross-association between solvent molecule and polymer in the PVPh/Ethyl Acetate solutions were measured using the FT-IR spectrum analysis method, and cross-association parameters of PC-SAFT model were estimated from experimental extents of cross-association. By using the estimated cross-association parameters between PVPh and solvent molecule, binodal and spinodal curves of liquid-liquid equilibria in PVPh/Ethyl Acetate and PVPh/Butyl Acetate solutions were calculated from PC-SAFT equation of state. The calculated binodal curves of these system were shown to be well agreeable with the experimental cloud temperature curves.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.4
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• pp.435-441
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• 1999

This study was designed to investigate the effects of roasting temperatures on the antinutritional factors and functional properties of sesame protein isolates. The protein contents a sesame protein isolates (SPI) prepared at roasting temperatures of 5$0^{\circ}C$, 10$0^{\circ}C$, 15$0^{\circ}C$ and 20$0^{\circ}C$ were 65.5%, 66.6%. 68.9% and 64.1%, respectively. Total phenolic compounds, condensed tannin and phytate contents of SPI was increased from 5$0^{\circ}C$ to 20$0^{\circ}C$. From color measurements, higher roasting temperature decreased 'L' and 'b' values significantly, but 'a' value was increased. The bulk density, fat absorption and water absorption of SPI was increased as the temperature of roasting was increased. Sesame protein isolates prepared by roasting at 5$0^{\circ}C$, 10$0^{\circ}C$ and 15$0^{\circ}C$ had higher emulsifying activity than those prepared by roasting at 20$0^{\circ}C$. Foaming capacity of SPI was not changed by roasting up to 10$0^{\circ}C$, but this property was reduced dramatically when roasted at 20$0^{\circ}C$.

• Membrane Journal
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• v.22 no.1
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• pp.23-34
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• 2012

In this study, we investigated the permeation property of single gases ($N_2$, $O_2$, $SF_6$, $CF_4$ through hollow fiber polymeric membrane (PSF, PC, PI) as a function of pressure and temperature to decide operating condition for $SF_6$ gas separation process. The results showed the gas permeation varied differentlydepending on the properties of gases and membrane. When permeance of each gases was represented as a function of temperature and pressure in 3 dimensional space, the surface of permeance was shown approximately flat. Thus, we established permeance models with forms of first-and second-order polynomial. These two models showed high goodness of fit. This indicates that the two polynomial models have enough applicability to predict the gas separation process.

• Proceedings of the Membrane Society of Korea Conference
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• 1999.10b
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• pp.117-119
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• 1999

• Journal of Aerospace System Engineering
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• v.17 no.2
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• pp.94-102
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• 2023

A nylon wire holding and release mechanism (HRM) has been widely used for deployable applications of CubeSat owing to its simplicity and low cost. In general, structural safety of solar panel with an HRM has been designed by performing structural analysis under a launch environment. However, previous studies have not performed thermal analysis for HRM in an on-orbit environment. In this study, Launch and Early Orbit Phase (LEOP) thermal analysis was performed to evaluate thermal stability of the mechanism in the orbital thermal environment of the pogo pin-based HRM applied to CubeSat. In addition, the effectiveness of the thermal design and performance of the pogo pin-based HRM were verified through a thermal vacuum test.

• 한국전자현미경학회:학술대회논문집
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• 1998.05a
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• pp.48-52
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• 1998

본 연구에서는 저온에서 InP 기판 위에 성장한 InAlAs 에피층에 존재하는 상분리와 규칙 현상을 투과전자현미경 관찰을 통해 관찰하였다. 저온에서 성장한 에피층에서 상분리의 거동이 크게 나타났으나 규칙 현상은 특정한 온도에서 최대를 나타낸다. $800^{\circ}C$ 이상에서 3분간의 열처리로 규칙 현상이 사라졌으나 상분리 현상은 변화를 보이지 않는다. 그러나 Zn가 포함된 장시간, 저온에서 열처리로 상분리 현상이 완전히 사라졌다.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.56-59
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• 2003

열가소성 폴리우레탄 탄성체는 유리전이온도가 낮은 soft segment와 융점이 높은 hard segment로 이루어진 블록공중합체이다. 이들 두 블록은 서로 상분리가 일어남으로써 각각 의 domain을 형성하며, 그 결과 hard segment는 가교의 역할을 행함으로써 우수한 탄성을 발휘할 수 있다. 이의 물성은 hard segment 및 soft segment의 조성과 화학구조 및 이들의 상분리 정도에 따라 다양하게 되며 또한 이의 전이온도도 다르게 변화시킬 수 있다. (중략)