• Journal of the Korean Chemical Society
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• v.53 no.5
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• pp.620-624
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• 2009

• Proceedings of the Membrane Society of Korea Conference
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• 2000.11a
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• pp.136-139
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• 2000

No Abstract, See Full Text

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2011.05a
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• pp.67-67
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• 2011

퍼멀로이의 내식성, 기계적 성질 등을 증가시키기 위해 복합도금을 실시하였다. 실리카 나노분말의 분산특성을 Zeta potential을 이용하여 측정하였으며 알칼리 도금액에서 퍼멀로이-실리카 복합도금을 실시하였다. 실리카 나노분말의 응집을 최소로 하기 위하여 전극의 RPM 변화, 첨가제와 초음파의 복합처리에 따른 변화, 전류 밀도 변화를 살펴보았다.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.249.1-249.1
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• 2003

The objective of the study was to develop an oral delivery system to increase the stability and efficacy of iron casein succinylate. Aqueous nanoparticles were prepared using complex coacervation of the oppositely charged chitosan and iron casein succinylate with polyethyleneglycol (PEG). The physicochemical properties of nanoparticles were investigated using dynamic light scattering, zeta potential and scanning electron microscopy. Chitosan-iron casein succinylate interactions were investigated in solid state by differential scanning calorimetry (DSC) and FT-IR spectrometry. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.247.2-247.2
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• 2003

To increase skin permeability of LMWH (Low Molecular Weight Heparin), ultradeformable liposomes were developed. Ultradeformable liposomes were developed by Egg phosphatidylcholine (Egg-PC) and edge activator. Entrapment efficiency, vesicle size and zeta potential of vesicles were determined and characterized for deformability and stability. Transepidermal permeation of LMWH was compared to saturated aqueous control in vitro. The steady-state flux and its maximum time were calculated from the flux curves. (omitted)

• Bulletin of the Korean Chemical Society
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• v.28 no.4
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• pp.667-674
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• 2007

Phase behavior for the mixed aqueous surfactant systems of cationic octadecyl trimethyl ammonium chloride (OTAC)/anionic ammonium dodecyl sulfate (ADS)/water was examined. Below the total surfactant concentrations of 1.5 m molal, mixed micelles were formed. At the total surfactant concentrations higher than 1.5 m molal, there appeared a region where mixed micelles and vesicles coexist. As the surfactant concentration increased, the systems looked very turbid and much more vesicles were observed. The vesicles were spontaneously formed in this system and their existence was observed by negative-staining transmission electron microscopy (TEM), small-angle neutron scattering (SANS) and encapsulation efficiency of dye. The vesicle region was where the molar fraction α of ADS to the total mixed surfactant was from 0.1 to 0.7 and the total surfactant concentration was above 5 × 10-4 molality. The size and structure of the vesicles were determined from the TEM microphotographs and the SANS data. Their diameter ranged from 450 nm to 120μm and decreased with increasing total surfactant concentration. The lamellar thickness also decreased from 15 nm to 5 nm with increasing surfactant concentration and this may be responsible for the decrease in vesicle size with the surfactant concentration. The stability of vesicles was examined by UV spectroscopy and zeta potentiometry. The vesicles displayed long-term stability, as UV absorbance spectra remained unchanged over two months. The zeta potentials of the vesicles were large in magnitude (40-70 mV) and the observed longterm stability of the vesicles may be attributed to such high ζ potentials.

• Textile Coloration and Finishing
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• v.27 no.2
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• pp.113-118
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• 2015

Poly(vinyl butyral), PVB was photooxidized by UV/ozone irradiation and the effect of UV energy on the surface properties of the UV-irradiated PVB film were investigated by the measurement of reflectance, surface roughness, contact angles, elemental composition, and zeta potential. With increasing UV energy, reflectance decreased in the visible and ultraviolet regions particularly at the wavelength of 400nm. The irradiation produced nano-scale surface roughness including the maximum peak-to-valley roughness increased from 274nm for the unirradiated PVB to 370nm at the UV energy of $5.3J/cm^2$. The improved hydrophilicity was due to the higher $O_{1s}/C_{1s}$ resulting from the introduction of polar groups such as C=O bonds. The surface energy of the PVB film increased from $35.3mJ/m^2$ to $39.3mJ/m^2$ at the irradiation of $15.9J/cm^2$. While the zeta potentials decreased proportionally with increasing UV energy, the cationic dyeability of the PVB increased accordingly resulting from the improved affinity of the irradiated PVB surfaces containing the photochemically introduced anionic and dipolar dyeing sites.

• Environmental Analysis Health and Toxicology
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• v.28
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• pp.6.1-6.7
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• 2013

Objectives In this study, we investigated the influence of ionic strength and natural organic matter (NOM) on aggregation and soil adsorption of citrate-coated silver nanoparticles (AgNPs). Methods Time-resolved dynamic light scattering measurements and batch adsorption experiments were used to study their aggregation and soil adsorption behaviors, respectively. Results The aggregation rate of AgNPs increased with increasing ionic strength and decreasing NOM concentration. At higher ionic strength, the AgNPs were unstable, and thus tended to be adsorbed to the soil, while increased NOM concentration hindered soil adsorption. To understand the varying behaviors of AgNPs depending on the environmental factors, particle zeta potentials were also measured as a function of ionic strength and NOM concentration. The magnitude of particle zeta potential became more negative with decreasing ionic strength and increasing NOM concentration. These results imply that the aggregation and soil adsorption behavior of AgNPs were mainly controlled by electrical double-layer repulsion consistent with the Derjaguin-Landau-Verwey-Overbeek theory. Conclusions This study found that the aggregation and soil adsorption behavior of AgNPs are closely associated with environmental factors such as ionic strength and NOM and suggested that assessing the environmental fate and transport of nanoparticles requires a thorough understanding of particle-particle interaction mechanisms.

• KSBB Journal
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• v.25 no.1
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• pp.97-102
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• 2010

The enhancement of immunity for atopic dermatitis with application of eicosapentaenoic acid (EPA)-loaded liposome was evaluated on NC/Nga mice. The EPA-loaded liposome was coated with thiol-chitosan. The liposomes were characterized with transmission electron microscopy (TEM), surface zeta potential & particle size analyzer (Zeta-PSA) and differential scanning calorimetry (DSC). The loading efficiency of EPA in the liposome was about 4.7%. The particle size of the EPA-Ioaded liposome was about 230 nm. The values of Immunoglobulin E (IgE), interleukin-4 (IL-4), and tumor necrosis factor-$\alpha$ (TNF-$\alpha$) were reduced significantly with application of the EPA-loaded liposome. The interferon-$\gamma$ (IFN-$\gamma$) value was increased with the application effect. It is concluded that EPA loaded liposome have immunity advancing effects in mouse model of atopic dermatitis.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.366-367
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• 2005

The effect of benzotriazole (BTA) on the adhesion force of silica and pad particle on Cu/TEOS wafer surfaces was investigated with and without the addition of BTA. Cu-BTA had the isoelectric point (IEP) at around pH 4$\sim$8. Pad particles were more positive zeta potentials than silica. The adhesion force initially decreased of silica and pad particle on Cu surfaces when BTA was added. However, the more BTA was added, the more adhesion force gradually increased with the increase of BTA concentrations. Then the adhesion force of pad particle was higher than silica. And TEOS didn't resulted increasing adhesion force like Cu when BTA was added in DI water.