• 환경위생공학
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• 제13권2호
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• pp.147-155
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• 1998

In this study, we prepared non-porous plasma membrane for having high permeability and selectivity and this membrane was deposited on the $Al_{2}O_{3}$ membrane by using $CHF_{3}$ & $SiH_{4}$ monomer. Also, we investigated for the permeation characteristics of the plasma polymer membrane by Ar plasma treatment. When the position of substrate was near cathode, the selectivity was increased with Ar plasma treatment time and rf-power. The pore size of $Al_{2}O_{3}$ membrane had an effect on the permeability and the position of substrate affected selectivity.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.642-644
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• 1999

We have prepared the plasma-polymerized membrane for pervaporation of organic-liquid mixtures by the plasma polymerization technique. Plasma polymerization techniques were utilized in the development of hydrophilic composite membranes having high hydrogen ion permeability and excellent dimensional stability. To develop an organic liquid permselective Membrane, suppressing membrane swearing as well as enhancing the solubility difference is impotant. the objectives of the present study are to disign a suitable membrane for an organic-mixture system by the control of the plasma-polymer solubility.

• Journal of Microbiology and Biotechnology
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• 제19권12호
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• pp.1635-1643
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• 2009

The aim of this study was to provide new insight into the mechanism whereby the housekeeping enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) locates to cell walls of Lactobacillus plantarum 299v. After purification, cytosolic and cell wall GAPDH (cw-GAPDH) forms were characterized and shown to be identical homotetrameric active enzymes. GAPDH concentration on cell walls was growth-time dependent. Free GAPDH was not observed on the culture supernatant at any time during growth, and provoked cell lysis was not concomitant with any reassociation of GAPDH onto the cell surface. Hence, with the possibility of cw-GAPDH resulting from autolysis being unlikely, entrapment of intracellular GAPDH on the cell wall after a passive efflux through altered plasma membrane was investigated. Flow cytometry was used to assess L. plantarum 299v membrane permeabilization after labeling with propidium iodide (PI). By combining PI uptake and cw-GAPDH activity measurements, we demonstrate here that the increase in cw-GAPDH concentration from the early exponential phase to the late stationary phase is closely related to an increase in plasma membrane permeability during growth. Moreover, we observed that increases in both plasma membrane permeability and cw-GAPDH activity were delayed when glucose was added during L. plantarum 299v growth. Using a double labeling of L. plantarum 299v cells with anti-GAPDH antibodies and propidium iodide, we established unambiguously that cells with impaired membrane manifest five times more cw-GAPDH than unaltered cells. Our results show that plasma membrane permeability appears to be closely related to the efflux of GAPDH on the bacterial cell surface, offering new insight into the understanding of the cell wall location of this enzyme.

• 한국표면공학회지
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• 제42권5호
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• pp.232-239
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• 2009

This study presented the effect of membrane thickness on hydrogen permeability. Microvoids on the surface of the membrane should not exist for the exact values of hydrogen permeability. Pd-Cu-Ni hydrogen alloy membranes were fabricated by Ni powder sintering, substrate plasma pretreatment, sputtering and Cu reflow process. And this leaded to void-free surface and dense film of Pd-Cu-Ni hydrogen alloy membrane. Hydrogen permeation test showed that hydrogen permeability increased from 2.7 to $15.2ml/cm^2{\cdot}min{\cdot}atm^{0.5}$ as membrane thickness decreased from 12 to $4{\mu}m$. This represented the similar trend as a hydrogen permeability of pure palladium membrane based on solution-diffusion mechanism.

• 공업화학
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• 제10권4호
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• pp.502-508
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• 1999

서로 다른 기공크기를 가진 $Al_2O_3$막을 기질로 사용하여 단량체인 $CHF_3$로 플라즈마 중합시키고, 플라즈마 중합된 막을 Ar 플라즈마로 처리하여 표면을 개질시켜 $O_2/N_2$에 대한 투과도와 선택도를 비교하여 그 특성을 검토하고 기질의 기공크기가 투과메카니즘에 미치는 영향을 살펴보았다. 중합된 고분자 막을 cathode에 근접한 위치에서 Ar 플라즈마의 처리 시간과 rf-power 출력에 따라 표면 처리하였을 때 질소에 대한 산소의 선택도는 크게 향상된, 반면 투과도는 저하됨을 확인하였다. 또한 동일한 증착조건에서 서로 다른 기공크기를 갖는 기질에 플라즈마 중합시켰을 때, 증착된 비 다공성막인 고분자막에서는 동일하게 용해-확산 모델이 적용되나, 비 다공성층을 통과한 분자들은 Knudsen 확산모델에 의해 기질의 크기와 투과도와의 상관관계를 나타냈으며, 이로부터 투과메카니즘은 중합된 고분자막의 기능기와 기질의 기공크기에 지배적인 영향을 받음을 알 수 있었다.

• Korean Membrane Journal
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• 제1권1호
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• pp.65-72
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• 1999

The surface of polypropylene membrane was modified by plasma treatment using Ar,$N_{2}$, $NH_{2}$ and $O_{2}$ Permeabilities for $CO_{2}$, $N_{2}$ and separation factor for $CO_{2}$ relative to $N_{2}$ were measured. The permeation experiments were performed by a variable volume method at $25^{\circ}C$ and 0.303MPa. The effects of the plasma conditions such as treatement time power input gas flow rate and pressure in the reactor on the transport properties of modified membrane were investigated. The surface of the plasma treated membrane was analyzed by means of FTIR-ATR XPS and AFM. The surface structure of the plasma treated membrane was fairly different from that of the untreated membrane. Although the permeation rates for both $CO_{2}$ and $N_{2}$ decreased with increasing plasma treatement time the separation factor was found to be improved by the plasma treatement. The operating conditions of plasma treatement imposed on membranes had notable effect on the permeability and separation factor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 D
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• pp.1702-1703
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• 1999

We have prepared the plasma-polymerized membrane for pervaporation of organic-liquid mixtures by the plasma polymerization technique. Plasma polymerization techniques were utilized in the development of hydrophilic composite membranes having high hydrogen ion permeability and excellent dimensional stability. To develop an organic liquid permselective membrane. suppressing membrane swelling as well as enhancing the solubility difference is important, the objectives of the present study are to design a suitable membrane for an organic-mixture system by the control of the plasma-polymer solubility.

• 멤브레인
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• 제11권1호
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• pp.38-49
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• 2001

우수한 열적, 화학적, 기계적 성질을 가진 폴리이미드 막의 표면을 Ar, $NH_3$ 플라즈마로 처리한 후 혼합기체$(CO_2/N_2=20/80 vol%)$의 투과 실험을 통하여 플라즈마 처리 조건이 기체 투과도와 분리성능에 어떠한 영향을 미치는지를 조사하였다. 투과실험은 $30^{\circ}$C, 5atm에서 variable volume method에 의해 행하여졌다. 표면개질된 폴리이미드 막의 투과거동에 대해 처리시간, 출력세기, 가스주입 유량 및 반응기 내의 압력과 같은 플라즈마 처리 조건의 영향을 조사하였다. 플라즈마 처리된 막의 표면은 FTIR-ATR, ESCA, AFM으로 분석하여 처리전후의 변화를 관찰하였다. 또한 플라즈마 처리시간에 따른 etching 효과와 흡수성은 weight loss와 contact angle를 측정하여 조사하였다. 그리고 투과 실험에 있어서 반응 온도의 변화에 따른 영향도 함께 연구되었으며, saturator를 이용한 dry 상태와 wet 상태에서 혼합가스에 대한 폴리이미드 막의 기체투과특성에 대한 실험 역시 수행되었다.

• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2002년도 Molecular and Cellular Response to Toxic Substances
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• pp.69-79
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• 2002

• Korean Chemical Engineering Research
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• 제44권6호
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• pp.588-596
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• 2006

폴리스티렌 막(polystyrene membrane, PS)의 표면을 Ar, $O_2$ 플라즈마로 처리하고, 처리 전후의 변화를 관찰하였고, $CO_2$, $N_2$의 투과도와 $N_2$에 대한 $CO_2$의 선택도는 연속흐름 기체 투과 분석장치(GPA)를 이용하여 측정하였다. Ar플라즈마 처리의 경우 O/C비율이 0에서 0.179로 증가하고, 표면 거칠기가 $15.86{\AA}$에서 $71.64{\AA}$로 증가함으로써 접촉각은 처리전의 $89.16^{\circ}$에서 $18.1^{\circ}$로 감소하였다. 따라서 플라즈마 처리는 막표면을 높은 친수성을 갖도록 만들었다. $CO_2$의 투과도와 선택도에 대한 Ar플라즈마 처리최적조건은 60 W, 2 min, $70^{\circ}C$이며, 투과도와 선택도는 각각 $2.1{\times}10^{-12}[m^3(STP){\cdot}m/m^2{\cdot}sec{\cdot}atm]$와 4.51이었다. $O_2$플라즈마 처리의 경우에, 접촉각은 O/C비율(0.189)과 표면 거칠기($57.10{\AA}$)의 증가에 의해 $13.56^{\circ}$로 감소하였다. 최적의 처리조건은 90 W-2 min-$70^{\circ}C$이며, 값 $7.1{\times}10^{-12}[m^3(STP){\cdot}m/m^2{\cdot}sec{\cdot}atm]$와 값 11.5이었다. 플라즈마 처리 후 막 표면의 변화는 표면에서의 교차결합과 식각효과의 경쟁적인 관계에 의해 결정된다. 결국 플라즈마 처리된 막의 투과도와 선택도가 플라즈마 기체, 처리시간, 출력세기등과 같은 플라즈마 상태를 제어함으로써 향상되었음을 확인할 수 있었다.