• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.235-238
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• 2005

Sulfonated poly(ether sulfone) copolymers (PESs) were synthesized using hydroquinone 2-potassium sulfonate (HPS) with other monomers (bisphenol A and 4-fluorophenyl sulfone). PESs with different $mole\%$ of hydrophilic group were prepared by changing the mole ratio of HPS in the polymerization reaction. The chemical structure and the thermal stability of these polymers were characterized by using $^1H-NMR$, FT-IR and TGA techniques. The PES 60 membrane, which has $60 mole\%$ of HPS unit in the polymer backbone, has a proton conductivity of 0.091 S/cm and good insolubility in boiling water. The TGA showed that PES 60 was stable up to $272^{\circ}C$ with a char yield of about $29\%\;at\;900^{\circ}C\;under\;N_2$ atmosphere. To investigate the single cell performance, the catalyst coated PES 60 membrane was used and a single cell test was carried out using $H_2/O_2$ gases as fuel and oxidant at various temperatures. We observed that the cell performance was enhanced by increasing the cell temperature. A current density of $1400 mA/cm^2$ at 0.60 V was obtained at $70^{\circ}C$.

• Archives of Pharmacal Research
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• v.23 no.4
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• pp.367-373
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• 2000

Cholic acid, conjugated with amine-terminated poly(W-isopropylacrylamide) (abbreviated as CA/ATPNIPAAm), was synthesized by a N, N'-dicyclohexyl carbodiimide (DCC)-mediated coupling reaction. Self-assembled CA/ATPNIPAAm micelles were prepared by a diafiltration method in aqueous media. The CA/ATPNIPAAm micelles exhibited a lower critical solution temperature (LCST) at $31.5^{\circ}C$. Micelle sizes measured by photon correlation spectroscopy (PCS) were approximately 31.6 $\times$$\times$ 5.8 nm. The CA/ATPNIPAAm micelles were spherical and their thermal size transition was observed by transmission electron microscope (TEM). A fluorescence probe technique was used for determining the micelle formation behavior of CA/ATPNIPAAm in aqueous solutions using Pyrene as a hydrophobic Probe. The critical micelle concentration (CMC) was evaluated as $8.9{\times}0^{-2}$ g/L. A drug release study was performed using indomethacin (IN) as a hydrophobic model drug. The release kinetics of IN from the CA/ATPNIPAAm micelles revealed a thermo-sensitivity by the unique character of poly(N-isopropylacrylamide) i.e. the release rate was higher at $25^{\circ}C$ than at $37^{\circ}C$.

• Membrane Journal
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• v.17 no.2
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• pp.140-145
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• 2007

In this study, 3-(trihydroxysilyl)-1-propanesulfonic acid (THS-PSA) was added to poly(vinyl alcohol) (PVA) membranes crosslinked with poly(styrene sulfonic acid-co-maleic acid) (PSSA_MA) to improve the separation characteristics toward water vapors in the air. The prepared membranes varying both PSSA_MA and THS-PSA amounts were also synthesized at different cross linking temperatures. Then, in order to investigate the separation characteristics of the resulting membranes, the dynamic vapor sorption (DVS) and vapor permeation experiments were carried out. The increase of cross-linking temperature showed longer time to reach the equilibrium sorption state from the dynamic vapor sorption experiments. PVA/PSSA_MA (3%)/THA-PSA(7%) prepared at $120^{\circ}C$ gave the highest permeability of 480 barrer at $35^{\circ}C$.

• Membrane Journal
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• v.18 no.1
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• pp.44-52
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• 2008

Pervaporation separation for water-ethanol mixtures has been carried out using crosslinked poly(vinyl alcohol) (PVA) membranes with poly(styrene sulfonic acid-co-maleic acid) (PSSA_MA) and at which tetraethylorthosilicate (TEOS) was introduced. The concentration of PSSA_MA was fixed 7 wt% over PVA and the TEOS contents, 3, 5, and 7 wt%, were varied against PVA. The composition of the feed mixtures were 10, 20, 30 and 50 wt% of water in it. PVA/PSSA_MA/5 wt% TEOS membrane showed the separation factor, 1730 and the permeability, $16.3g/m^2{\cdot}hr$ for water : ethanol = 10 : 90 at $50^{\circ}C$.

• Korean Membrane Journal
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• v.6 no.1
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• pp.16-23
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• 2004

The silica containing carbon (C-SiO$_2$) membranes were fabricated using poly(imide siloxane) (PIS) having -CO- swivel group. The characteristics of porous C-SiO$_2$ structures prepared by the pyrolysis of poly(imide siloxane) were related with the micro-phase separation between the imide block and the siloxane block. Furthermore, the nitrogen adsorption isotherms of the CMS and the C-SiO$_2$ membranes were investigated to define the characteristics of porous structures. The C-SiO$_2$ membranes derived from PIS showed the type IV isotherm and possessed the hysteresis loop, which was associated with the mesoporous carbon structures, while the CMS membranes derived from PI showed the type I isotherm. For the molecular sieving probe, the C-SiO$_2$ membranes pyrolyzed at 550, 600, and 700$^{\circ}C$ showed the O$_2$ permeability of 924, 1076, and 367 Barrer (1 ${\times}$ 10$\^$-10/㎤(STP)cm/$\textrm{cm}^2$$.$s$.$cmHg) and O$_2$/N$_2$ selectivity of 9, 8, and 12.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.4
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• pp.403-410
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• 2015

Viral nervous necrosis (VNN) is a serious disease of sevenband grouper Epinephelus septemfasciatus in Korean aquaculture farms. However, we suggest the following preventative methods for hatcheries: 1) disinfecting rearing water, 2) selecting spawners via ELISA and PCR, 3) selecting eggs via PCR, 4) disinfecting fertilized eggs, and 5) proper facilities management. When these methods are implemented, nervous necrosis virus (NNV)-free fish are produced because vertical and horizontal transmission is prevented. However, horizontal transmission of NNV through rearing seawater sourced from the environment during grow-out stages in sea cages can still occur. Live NNV vaccines with a low rearing temperature or Poly(I:C) immunization are very effective at preventing horizontal transmission of NNV in rearing farms. Furthermore, even after VNN is contracted, fish mortality can be reduced by administering Poly(I:C).

• Textile Coloration and Finishing
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• v.13 no.4
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• pp.249-255
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• 2001

To interpret the dyeing behavior of PTT fiber with C. I. Disperse Violet 1, the thermodynamic Parameters of dyeing, such as standard affinity, heat of dyeing(enthalpy change), entropy change, diffusion coefficient, and activation energy of diffusion, were obtained from isotherms and dyeing rates at various temperatures and compared with those of PET fiber. The heat of dyeing(enthalpy change) and the entropy change of PTT fiber showed smaller negative values than those of PET fiber. This means that the dye molecules in the PTT fiber are combined more loosely than in the PET fiber and that is due to the flexibility of polymer chains of PTT fiber. The diffusion coefficients of C. I. Disperse Violet 1 into the PTT fiber were larger than those for PET fiber, and the activation energy of diffusion on PTT fiber was smaller than that on PET fiber.

• Journal of Sensor Science and Technology
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• v.18 no.2
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• pp.147-153
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• 2009

A thermal flow sensor has been fabricated and characterized, consisting of a center resistive heater surrounded by two upstream and one downstream temperature sensing resistors. The heater and temperature sensing resistors are fabricated from nitrogen-doped(n-type) polycrystalline silicon carbide(poly-SiC) deposited by LPCVD(low pressure chemical vapor deposition) on LPCVD silicon nitride films on a Si substrate. Cavities were etched into the Si substrate from the front side to create suspended silicon nitride membranes carrying the poly-SiC elements. One upstream sensor is located $50{\mu}m$ from the heater and has a sensitivity of $0.73{\Omega}$/sccm with ${\sim}15\;ms$ rise time in a dynamic range of 1000 sccm. N-type poly-SiC has a linear negative temperature coefficient and a TCR(temperature coefficient of resistance) of $-1.24{\times}10^{-3}/^{\circ}C$ from room temperature to $100^{\circ}C$.

• IMMUNE NETWORK
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• v.23 no.2
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• pp.16.1-16.19
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• 2023

Bacillus Calmette-Guerin (BCG) vaccine is the only licensed vaccine for tuberculosis (TB) prevention. Previously, our group demonstrated the vaccine potential of Rv0351 and Rv3628 against Mycobacterium tuberculosis (Mtb) infection by directing Th1-biased CD4⁺ T cells co-expressing IFN-γ, TNF-α, and IL-2 in the lungs. Here, we assessed immunogenicity and vaccine potential of the combined Ags (Rv0351/Rv3628) formulated in different adjuvants as subunit booster in BCG-primed mice against hypervirulent clinical Mtb strain K (Mtb K). Compared to BCG-only or subunit-only vaccine, BCG prime and subunit boost regimen exhibited significantly enhanced Th1 response. Next, we evaluated the immunogenicity to the combined Ags when formulated with four different types of monophosphoryl lipid A (MPL)-based adjuvants: 1) dimethyldioctadecylammonium bromide (DDA), MPL, and trehalose dicorynomycolate (TDM) in liposome form (DMT), 2) MPL and Poly I:C in liposome form (MP), 3) MPL, Poly I:C, and QS21 in liposome form (MPQ), and 4) MPL and Poly I:C in squalene emulsion form (MPS). MPQ and MPS displayed greater adjuvancity in Th1 induction than DMT or MP did. Especially, BCG prime and subunit-MPS boost regimen significantly reduced the bacterial loads and pulmonary inflammation against Mtb K infection when compared to BCG-only vaccine at a chronic stage of TB disease. Collectively, our findings highlighted the importance of adjuvant components and formulation to induce the enhanced protection with an optimal Th1 response.

• Textile Coloration and Finishing
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• v.2 no.4
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• pp.231-236
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• 1990

The diffusion coefficient of C.I. Disperse Red 4 in the dyeing of carrier-pretreated poly (ethylene terephthalate) film was Investigated by Sekido's film-rolled method. From the result it was shown that the diffusion coefficient increases exponentially with the content-ration of carrier in the film, and, for the films containing same concentration of carrier, the carrier effect was enhanced with the molar volume of the carriers. The greater carrier effect was accompanied by the decrease in diffusion activation energy and entropy, which shows that the carrier with larger molar volume plasticizes PET film to more extent.