• Archives of Pharmacal Research
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• v.10 no.2
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• pp.75-79
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• 1987

Liposomes were studied as a drug delivery system. Multilamellar vesicles, small unilamellar vesicles and large unilamellar vesicles containing cytarabine were prepared using egg yolk lecithin and cholesterol. Large unilamellar vesicles showed the highest encapsulation efficiency of all and their encapsulation efficiency increased as the buffer volume decreased. Cholesterol increased the stability of liposomal drug products as drug carriers and reduced the permeability of drug across the liposomal membrane. The release rate of cytarabine increased with incubation temperature and decreased with cholesterol incorporation in liposomal membrane. The release mechanism of cytarabine from large unilamellar vesicles in vitro was chiefly due to simple diffusion across the liposomal membrane rather than liposomal rupture.

• Wind and Structures
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• v.26 no.6
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• pp.355-367
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• 2018

This paper studies the aerodynamic stability of a tensioned, geometrically nonlinear orthotropic membrane structure with hyperbolic paraboloid in sag direction. Considering flow separation, the wind field around membrane structure is simulated as the superposition of a uniform flow and a continuous vortex layer. By the potential flow theory in fluid mechanics and the thin airfoil theory in aerodynamics, aerodynamic pressure acting on membrane surface can be determined. And based on the large amplitude theory of membrane and D'Alembert's principle, interaction governing equations of wind-structure are established. Then, under the circumstance of single-mode response, the Bubnov-Galerkin approximate method is applied to transform the complicated interaction governing equations into a system of second-order nonlinear differential equation with constant coefficients. Through judging the frequency characteristic of the system characteristic equation, the critical velocity of divergence instability is determined. Different parameter analysis shows that the orthotropy, geometrical nonlinearity and scantling of structure is significant for preventing destructive aerodynamic instability in membrane structures. Compared to the model without considering flow separation, it's basically consistent about the divergence instability regularities in the flow separation model.

• Membrane Journal
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• v.22 no.6
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• pp.424-434
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• 2012

In this study, a ceramic membrane was prepared by CVD. Tube type alpha alumina support was used for substrate and added the Ga salt in intermediate layer. Synthesized method was counter diffusion CVD method at $650^{\circ}C$ with tetramethylorthosilane (TMOS). Gas permeation was measured at $600^{\circ}C$ using single-component $H_2$, $N_2$, $CO_2$ and $CH_4$. During the steam treatment, $H_2/N_2$ permselectivity of non-Ga silica membrane was decreased 926 to 829 at $600^{\circ}C$. On the other hand $H_2/N_2$ permselectivity of added Ga silica membrane was stable 910 to 904 at $600^{\circ}C$. These results show that the metal-doped membranes improved steam stability for gas separation.

• Proceedings of the Membrane Society of Korea Conference
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• 2005.11a
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• pp.170-173
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• 2005

• Transactions of the Korean hydrogen and new energy society
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• v.30 no.3
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• pp.227-236
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• 2019

In this work, preparation and characterizations of hybrid membranes containing sulfonated poly(arylene ether sulfone) (SPES) and sulfonated poly(vinylidene fluoride-co-hexafluoropropylene) (SPVdF-co-HFP) (20, 30 or 40 wt%) were carried out. The structure of hybrid membranes was confirmed using X-ray diffraction (XRD) analysis and the Fourier transform infrared (FT-IR) spectroscopy. The prepared SPAES/SPVdF-30 membrane exhibits higher ionic conductivity of 68.9 mS/cm at $90^{\circ}C$ and 100% RH. Besides, the other studies showed that the hybrid membrane has good oxidation stability, thermal stability, and mechanical stability. Thus, we believe that the prepared hybrid membrane is suitable for the development of membranes for fuel cell applications.

• Culinary science and hospitality research
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• v.4
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• pp.129-146
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• 1998

The effects of vitamin E supplement on 15%(w/w diet) perilla or corn oils were studied in rat hepatocellular chemical carcinogenesis induced by modified Solt & Farber model, which consists of 20mg/kg body weight diethylintrosamine(DEN) injection, 3 weeks feeding of 0.02%2-acetylaminofluorene(2-AAF) and partial hepatectomy. The area of placental glutathione S-transferase(GST-P) positive foci tended to be smaller in perilla oil group had lower thiobarbituric acid reactive substances(TBARS) CONTENT. Fatty acid compositions in microsomal membrane were reflected by dietary fatty acid compositions, and not affected by carcinogen treatment or vitamin E supplement. By vitamin E supplement, linolenic acid contents of perilla oil group were much increased. By carcinogen treatment, membrane stability decreased significantly in corn oil, but maintained in perilla oil groups Vitamin E supplemental effect was noticed only in the corn-carcinogen group. Perilla oil may prevent hepatocarcinogenesis by maintaining membrane stability and by reducing cytochrome P-450 content. Vitamin E supplement did not seem to have the effect on hepatocarcinogenesis, but prevented lipid peroxidation, reduced cytochrome P-450 content and maintained membrane stability.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.4
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• pp.58-67
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• 1998

A sectional analysis of sheet metal forming process with an arbitrary tool shape is proposed in the present work. To improve the numerical convergence in the conventional membrane sectional analysis, the Bending Energy Augmented Membrane (BEAM) elements had been developed. The BEAM elements particularly improve the stability and convergence of the finite element method for the case of deep drawing. In this work, the FERGUBON spline (C$^2$-continuous) was used to fit the deformed mesh to smooth the given curves and calculate the local curvature of the deformed sheet. The fittings of the deformed sheet and tool surface profile ensure the stability and the convergence of the finite element analysis of highly nonlinear stamping processes. A center floor section and front fender section are analyzed to show the accuracy and robustness of the approach. The results obtained by the proposed approach are compared with the available experimental data.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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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.

• Proceedings of the Membrane Society of Korea Conference
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• 1999.10a
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• pp.93-116
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• 1999

MF membrane element was specially designed for water purification and VSA process which can solve the fouling problem. Especially VSA process is developed for the SK Chemicals' asymmetric microfiltration hollow fiber membranes. In case of outside-to-in filtration process, MF membrane element showed the excellent flux stability caused by cleaning ability of VSA process . Simultaneous back-washing with VSA consideratbly enhances cleaning efficiency. From the result the possibility of the replacement of chemical coagulation and sand filtration process with newly developed VSA process was revealed.

• Proceedings of the Membrane Society of Korea Conference
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• 1999.07a
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• pp.63-66
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• 1999

MF membrane element was specially designed for water purification and VSA process which can solve the fouling problem. Especially VSA process is developed for the SK Chemical's asymmetric microfiltration hollow fiber membranes. In case of outside-to-in filtration process, MF membrane element showed the excellent flux stability caused by cleaning ability of VSA process. Simultaneous back- washing with VSA considerably enhances cleaning efficiency. Form the result, the possibility of the replacement of chemical coagulation and sand filtration process with newly developed VSA process was revealed.