• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2005년도 수소연료전지공동심포지움 2005논문집
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• pp.93-96
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• 2005

고분자전해질형 연료전지에서는 수소이온의 이온전도성 저하를 방지하기 위하여 외부에서 가습하여 주는 방식이 일반적이지만, 가습에 소요되는 부품을 일부라도 제거할 경우 연료전지의 효율은 높이고 제작단가도 경감할 수 있다. 이를 위하여 저가습 및 무가습 실험을 수행하였으며, 정확한 data의 수집과 시험장비의 자동제어를 위하여 National Instrument사의 compact field point (cFP)를 사용하였다. Humidifier와 heater의 온도를 조절하여 공급유체의 상대습도 및 온도를 각각 조절하였으며, 이에 필요한 이론적 온도는 Antoine equation 을 사용하여 산정하였다. Anode와 cathode 양측 $100\%$ 가습 경우를 기준으로 가습량을 조절하면서 실험을 수행하였으며 성능 차이를 그래프로 도시하여 양측의 변화에 대한 영향을 볼수 있도록 하였다. Stack의 온도가 $70^{\circ}C$이고 양측 무가습일 경우에 성능 측정이 어려워서 stack의 온도를 저온에서부터 변화시키면서 무가습 성능을 실시간으로 측정하여 보았다. 일반적으로 hydronium ion은 anode측에서 cathode측으로 계속 이동하여야 전기를 생성할 수 있으므로 cathode측 무가습이 anode측 무가습보다 성능이 더 잘 나오는 것으로 예측하였으나 이와 반대되는 경향의 실험 결과를 얻었다. 양측 무가습의 경우에는 공기 중의 상대습도와 back diffusion 등에 영향을 받을 수 있으므로 각종 변수들의 영향을 분리하여 관찰할 수 있는 실험을 수행 중에 있다.

• KSBB Journal
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• 제10권1호
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• pp.30-37
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• 1995

Membrane-bound alcohol dehydrogenase(ADH) was purified to homogeneity from the acetic acid producing bacteria, Acetobacter sp. KM. The enzyme was solubilized and extracted with Triton X-100 and purified using the Mono-Q ion exchange chromatography and Superose 12 gel filtration chromatography. The enzyme was purified to 12-fold with a yield of 30%. The molecular weight of the purified enzyme was to be 335 KDa. SDS-PAGE of the enzyme showed two subunits with molecular weights of 79 KDa and 49 KDa. It indicated that the enzyme consisted of three subunits of the 79 KDa and two subunits of the 49 KDa. The purified .ADH preferentially oxidized straight chain aliphatic alcohol except methanol. Formaldehyde, acetaldehyde and glutaraldehyde were also oxidized. The apparent Km for ethanol was 1.04 mM and the optimum pH and temperature were 5.0∼6.0 and 32$^{\circ}C$, respectively. V2O5 and divalent cation such as ZnCl2 and NiCl2 inhibited enzymatic activity.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.836-839
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• 2009

중소형 폐기물소각설비의 저압 저질의 포화증기를 이용한 폐열발전용 용수처리에 관한 연구를 수행 하였다. 기존 소각설비에 적용된 강산성 이온교환수지형 연수기에 역삼투압 멤브레인 처리와 강염기성 이온교환수지형 용수처리를 연결하여 보일러 용수를 처리한 결과, KS B6209의 30 $kg/cm_2$ 증기 압력의 보일러 용수기준에는 적합하였고, 증기의 비체적으로 증기 농도로 환산하면. 역삼투압법처리에 의한 방법보다는 강염기성이온교환수지형 용수처리를 연계 처리한 결과가 중소형폐기물소각설비의 저압증기터빈발전에 보다 적합한 것으로 나타났다.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.246-246
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• 2006

Ionic polymer-metal composite (IPMC) soaked with various ionic liquids was prepared by using polystyrene sulfonic acid-grafted poly(vinylidene fluoride-co-hexafluoropropylene) as ion-exchange membrane (IEM). The prepared IPMCs were effectively deformed three times larger and actuated for 300 times longer than those of Nafion with water at the same applied conditions. The experimental results indicated than the increase in the bending capability can be caused by the increase in the improved properties of the IEMs and ionic liquids such as uptake content and ionic conductivity. And air-operating stability of the IPMCs is appreciably governed by various physical and electrochemical properties of soaked solvents in IEMs.

• 상하수도학회지
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• 제25권6호
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• pp.989-994
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• 2011

Nitrate contamination of groundwater is a common problem throughout intensive agriculture areas (non-point source pollution). Current processes (e.g. ion exchange and membrane separation) for nitrate removal have various disadvantages. The objective of this study was to evaluate electrochemical method such as electroreduction using bipolar ZVI packed bed electrolytic cell to remove nitrate from groundwater at field pilot. In addition ammonia stripping tower continuously removed up to 77.0% of ammonia. Bipolar ZVI packed bed electrolytic cell also removed E.coli. In the field pilot experiment for groundwater in 'I' city (average nitrate 30~35 mg N/L, pH 6.4), maximum 99.9% removal of nitrate was achieved in the applied 600 V.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.549-550
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• 2006

Mobile fuel cell is highlighted in these days because mobile fuel cell can contain more energy than existing batteries. Nowadays mobile devices like cellular phone, PMP(portable multi-media player), notebook, and etc. need more energy, But existing batteries like Li-ion or Ni-MH batteries are not going to satisfy such demands. In this paper, mobile fuel cell is developed. Its size is 50*70*8mm and it is made of aluminium plates. The fuel cell type is PEM and the fuel is pure hydrogen and oxygen.

• 한국가시화정보학회지
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• 제13권2호
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• pp.16-21
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• 2015

Concentration polarization(CP) phenomena show great potential on desalination technology. As we can control the dimension of silicon based nanochannel system, it can be used to model ion exchange membrane. In this study, to investigate the effect of nanochannel number and working conditions on the CP based desalination process, nanochannel based microfluidic system is fabricated. First, we optimized nanochannel number and working conditions to conduct visualization study on CP based desalination process. Second, we visualized the desalination process with fluorescent dye in the desalination chip. We also visualized that the particles also can be removed by the CP based desalination process.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1996년도 정기총회 및 학술발표회
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• pp.33-33
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• 1996

An ectodomain of gp41, the transmembrane fusion protein of HIV, without the fusion peptide region was expressed using pET system in E. coli. The expressed protein gp41core, was isolated as inclusion body and was purified by ion-exchange chromatography after solubilized in 6M urea. The purified denatured protein was renaturated and the folded domain of gp41core was identified by the presence of the proteolysis resistence domain and a high content of ${\alpha}$-helical secondary structure. (omitted)

• Preventive Nutrition and Food Science
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• 제8권2호
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• pp.154-157
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• 2003

A peptide inhibiting HIV-1 pretense was isolated from the hydrolysate of manila clam (Ruditapes philippinarum) proteins digested with thermolysin. The peptide was purified by using membrane filtration, gel permeation chromatography, ion exchange chromatography, and reverse phase HPLC, The amino acid sequence of the peptide was determined to be Ile-Tyr-Glu-Gly. This tetrapeptide sequence exists in some proteins of Physarum polycephalum and Mycobacterium smegmatis. Chemically synthesized Ile-Tyr-Glu-Gly showed the $IC_{50}$/ value of 22.3 $\mu$M.

• 청정기술
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• 제18권4호
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• pp.341-346
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• 2012

연구자들은 용수 및 폐수 내에 함유되어 있는 중금속을 효과적으로 제거하기 위한 많은 공정을 연구하고 있다. 많은 공정들 중에서 특히, 물리, 화학적 공정은 생물학적 공정과 비교해볼 때 대체로 간단하고 높은 중금속 제거효율을 얻을 수 있다. 최근에는 방사능원소에 대한 위험성 때문에 물리, 화학적 방법들에 대한 관심이 다시 급격하게 증가하고 있다. 이 연구에서는 화학적 침전, 이온 교환, 전기투석, 그리고 막 분리 등과 같은 다양한 물리, 화학적 공정들을 소개하고자 한다.