• Bulletin of the Korean Chemical Society
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• v.21 no.8
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• pp.817-822
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• 2000

Crack-free hard coating siIica films were prepared by sol-gel processfrom twokinds of silicon alkoxide (tetra-ethoxysilane and methyltrimethoxysilane) and two kinds of alcohol (methanol and isopropyl alcohol) with an acid catalyst,acetic acid. A silicate framework of the precursor solution was investigated by infrared spectros-copy (IR) in the process of hydrolysis and condensation. Theextent of the condensation in the intermediates was elucidated by gel permeation chromatography (GPC) and 29Si-NMR spectroscopy. The hard coating films werecharacterized by IR,scanning electron microscope (SEM), thermo gravimetric analyzer (TGA) and dif-ferential scanning calroimeter (DSC). The synthetic condition for the crack-free and transparent silica film for-mation was optimized interms of starting materials for the precursor solution as well as preparation method of the silica film.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.2
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• pp.153-160
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• 2000

A Particle Image Velocimetry(PIV) algorithm is developed to analyze whole flow field both qualitatively and quantitatively. The practical use of PIV requires the use of fast, reliable, computer-based methods for tracking numerous particles suspended in a flow field. The TSS, NTSS, FFT-Hybrid, which are developed in the area of image compression and coding, are introduced to develop fast vector search algorithm. The numerical solution of the lid-driven cavity flow by the ADI algorithm with the Wachspress Formula is introduced to produce synthetic data for the validation of the tracking algorithms. The algorithms are applied to image data of real flow experiments. The comparisons in CPU time and mean error show, with a small loss of accuracy, CPU time for tracking is reduced considerably.

• Journal of the Korean Ceramic Society
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• v.44 no.2 s.297
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• pp.89-92
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• 2007

PbSe, with a band gap in the mid-infrared and a samll effective mass, is an interesting material for optical and electrical applications in infrared region. Various colloidal synthetic routes for synthesizing PbSe quantum dot nanoparticles have been developed in the last couple of years. In this work, stable colloidal solutions containing crystalline PbSe particles in the order of 5-15 nm were synthesized using different amount of acetic acid in high boiling coordinating solvents. The size and shape of PbSe nanoparticles was greatly influenced by coexistence of acetic acid in synthetic medium. It was observed by TEM that the shape of PbSe nanoparticles with different amount of acetic acid was changed from spherical to cube or star types.

• Textile Coloration and Finishing
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• v.15 no.6
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• pp.18-26
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• 2003

Nylon 6.6 was treated with anionic synthetic tanning agent at different pH values, temperatures and liquor ratios to determine exhaustion properties. Treatments using syntan were conducted to the undyed nylon 6.6 fiber and three acid dyeings and then samples of the bath solution were subjected to HPLC analysis. Mass analysis was considered to determine the syntan components. In addition, the effect of applications using syntan and syntan/cation in improving the stain resistance was observed. The optimum treatment condition of syntan was achieved and the major component of syntan, being exhausted to the nylon substrates, was determined. In terms of stain blocking effect, a significant improvement was achieved by the syntan and syntan/cation treatments.

• Journal of Life Science
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• v.6 no.1
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• pp.34-39
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• 1996

The biopolymer membrane could be formed using marine polysaccharides. Chiotsan and alginate were used for the formation of capsule membrane to mimic the fish eggs such as flying fish eggs and salmon eggs. The size of capsules ranging 1 to 5mm was prepared and the mechanical tests were performed to determine the mechanical similarities to natural fish eggs. The similar mechanical pattern between the synthetic capsules and natural eggs could be found. The controlling parameters for the strength of capsules were pH of the chitosan solution. This encapsulation technique can be broadly applied to medical, engineering as well as food areas.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.609-612
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• 2011

Amphiphilic (porphyrin)Sn$(OH)_2$ molecular building block can directly translate into well-defined solid-state microcrystalline structures. The crystalline diamond plates are obtained from ethanol and crystalline square plates are grown from methanol solution. With a simple synthetic manipulation during the microcrystal growth, the morphologies can be controlled by adopting different molecular packing. Consequently, morphologies of microcrystals have been diversified. Furthermore, the macroscopic crystals were obtained in the presence of cetyltrimethylammonium bromide (CTAB).

• Biomolecules & Therapeutics
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• v.20 no.1
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• pp.19-26
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• 2012

There are many cyclic peptides with diverse biological activities, such as antibacterial activity, immunosuppressive activity, and anti-tumor activity, and so on. Encouraged by natural cyclic peptides with biological activity, efforts have been made to develop cyclic peptides with both genetic and synthetic methods. The genetic methods include phage display, intein-based cyclic peptides, and mRNA display. The synthetic methods involve individual synthesis, parallel synthesis, as well as split-and-pool synthesis. Recent development of cyclic peptide library based on split-and-pool synthesis allows on-bead screening, in-solution screening, and microarray screening of cyclic peptides for biological activity. Cyclic peptides will be useful as receptor agonist/antagonist, RNA binding molecule, enzyme inhibitor and so on, and more cyclic peptides will emerge as therapeutic agents and biochemical tools.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.153.1-153.1
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• 2011

For the stars cooler than the Sun, it is difficult to determine the stellar parameters and chemical abundances because of the strong molecular lines in the optical region. Therefore the NIR high-resolution spectra, such as those obtained by IGRINS would be a solution to determine the stellar parameters for late-type stars, such as M dwarfs. As using the NIR high-resolution spectra, we are expecting that it would be more reliable to compare observed spectra with synthetic spectra for the stellar parameters. In order to confirm the method by using high-resolution spectra in NIR band, it should be cross-checked against the stellar parameters from optical high-resolution spectra. We have derived the stellar parameters of M dwarfs using the synthetic spectra in the long wavelength region of the optical spectra (over 8000 $\bar{A}$), which is relatively less contaminated by molecular lines as well as telluric lines.

• Bulletin of the Korean Chemical Society
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• v.24 no.3
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• pp.339-344
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• 2003

The conformation of synthetic oligosaccharide can be elucidated by employing molecular modeling and highfield proton NMR (nuclear magnetic resonance) spectroscopy. Information with respect to the composition and configuration of saccharide residues and the sequence and linkage positions of the oligosaccharide can be obtained by employing a variety of one- and two-dimensional NMR techniques and molecular modeling. These techniques are also useful in establishing the solution conformation of the oligosaccharide moiety. This study is focused on the elucidation of linkage positions of synthetic trisaccharides, Gal(β1-4)Glc(β1-3)Glc, Gal(β1-4)Glc(β1-4)Glc and Gal(β1-4)Glc(β1-6)Glc.

• Journal of Environmental Science International
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• v.12 no.10
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• pp.1061-1069
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• 2003

The adsorption behaviors of strontium and cesium ions on fly ash, natural zeolites, and zeolites synthesized from fly ash were investigated. The zeolites synthesized from fly ash had greater adsorption capabilities for strontium and cesium ions than the original fly ash and natural zeolites. The maximum adsorption capacity of synthetic zeolite for strontium and cesium ions was 100 and 154 mg/g, respectively, It was found that the Freundlich isotherm model could fit the adsorption isotherm. The distribution coefficients (K$\_$d/) for strontium and cesium ions were also calculated from the adsorption isotherm data, The distribution coefficients decreased with increasing equilibrium concentration of strontium and cesium ions in solution. By studying the removal of cesium and strontium ions in the presence of calcium, magnesium, sodium, potassium, sulfate, nitrate, nitrite, and EDTA (in the range of 0.01 - 5 mM) it was found that these coexistence ions competed for the same adsorption sites with strontium and cesium ions.