• Proceedings of the Korea Crystallographic Association Conference
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• 2003.05a
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• pp.20-20
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• 2003

A new and simple method has been developed to synthesize highly crystalline and monodisperse maghemite (γ-Fe₂O₃) and zirconia (ZrO₂) nanocristallites. High temperature aging of metal-surfactant complex was founded to generate monodisperse nanoparticles, wherein the nuclei were prepared by the thermal decomposition of iron-oleate complex in case of iron oxide and nonhydrolytic sol-gel reaction in case of zirconia respectively. By varying the experimental conditions, in other words concentration of surfactants, kind of metal precursor, reaction temperature and so on, the diameter of spherical nanoparticles could be controlled at various size. The synthesized nanoparticles were characterized by electron diffraction, X-ray diffraction, and low- and high-resolution transmission electron microscope.

• Corrosion Science and Technology
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• v.14 no.5
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• pp.207-212
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• 2015

The purpose of this research was to synthesize fluorine modified waterborne polyurethane dispersion (F-WPU) by soap-free (internal emulsifier) emulsion polymerization techniques, to prepare coating solution based on fluorine modified waterborne polyurethane dispersion (F-WPU) and to compare the chemical and thermo-mechanical properties on the electrogalvanized steel sheet. Environmentally friendly F-WPU was prepared with a fluorinated polyol containing 60 wt% of fluorine. There are various ways of combining a wide variety of fluorinated polyols and diisocyanate to exhibit novel properties of waterborne polyurethane dispersion. Components of coating solution were largely divided into 4 kinds i.e., F-WPU, acrylic emulsion, silane coupling agent, and colloidal silicate. F-WPU coating solution on the electro-galvanized steel sheet showed excellent properties of corrosion resistance, alkali resistance and heat resistance, as compared to other coating solutions using a general waterborne resin. The F-WPU coating solution's reliable effects are possibly due to the fluorine atoms incorporated even in a small amount of F-WPU.

• Journal of the Semiconductor & Display Technology
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• v.16 no.1
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• pp.45-51
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• 2017

Poly(urethane acrylate) siloxane oligomers with Interpenetrating polymer netwoked nanoparticles were prepared to synthesize hard coating solution by reaction with diisocyanates. The diisocyanate combined siloxane hard coating solution showed more flexibility than the siloxane solution. In addition, diisocyanate resulted in improvement of curl property and surface hardness in the siloxane solution. Of the used diisocyanates, isophorone diisocyanate and acryloyloxy ethyl diisocyanate were good for UV hard coating solution. This effect will decrease brittleness in the siloxane solution using for plastic display plate.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.611-611
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• 2013

In this study, iron oxide nanoclusters layer (Nc) was prepared onto functionalized silicon substrate by wet method. The amine-terminated SAM fabricated on silicon substrate (APTMS/Si) was carried out by UV-treatment and immersed into the FeCl3/HCl aqueous solution. Then, Nc were immobilized onto oxidized SAM silicon substrate (SAMs/Si) through electrostatic interaction between cationic Nc and anionic SAMs/Si. This catalytic layer (Nc/SAMs/Si) was used to grow carbon nanotubes (CNTs). The characterization results clearly show that the well-graphitized CNTs were synthesized by using functionalized silicon substrate as a template having appropriate density of catalyst. These consequences show that SAM containing template is important to achieve the effective layer of catalyst to synthesize CNTs.

• Journal of Korea Water Resources Association
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• v.53 no.6
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• pp.463-467
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• 2020

The main feature of this study is to automatically synthesize square images by sending aerial photographs and images from unmanned aerial vehicles (drons). It may be applicable to the cloud server, and to apply analytical algorithms for the suitable purpose of image processing. Drone imaging analysis is a process that can be used in various fields such as finding contaminated area of green algae, monitoring forest fire, and managing crop cultivation.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1009-1010
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• 2006

In this study, we attempt to synthesize the cordierite from the reaction of fly-ash, alumina, silicon dioxide, and magnesia powders. For the purpose of air purification, the honeycomb filter with porous cordierite was fabricated from the combination of synthetic cordierite and pore forming agent. Fabricated porous cordierite honeycomb was prepared with high porosity (58%), and good compressive strength (69MPa).

• Journal of Powder Materials
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• v.25 no.4
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• pp.346-354
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• 2018

Over the last decade, the study of the synthesis of semiconductor colloidal quantum dots has progressed at a tremendous rate. Colloidal quantum dots, which possess unique spectral-luminescent characteristics, are of great interest in the development of novel materials and devices, which are promising for use in various fields. Several studies have been carried out on hot injection synthesis methods. However, these methods have been found to be unsuitable for large-capacity synthesis. Therefore, this review paper introduces synthesis methods other than the hot injection synthesis method, to synthesize quantum dots with excellent optical properties, through continuous synthesis and large capacity synthesis. In addition, examples of the application of synthesized colloid quantum dots in displays, solar cells, and bio industries are provided.

• Journal of Applied Biological Chemistry
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• v.43 no.4
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• pp.269-272
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• 2000

The ginseng growth-promoting bacterium Pseudomonas fluorescens KGPP 207 synthesized indole-3- acetic acid (IAA) from L-tryptophan, indole-3-pyruvic acid (IPyA), and indole-3-acetaldehyde (IAAld), but not from indole-3-acetamide (lAM) and other intermediates of various IAA biosynthetic pathways in the experiment with indole compound supplemented cell suspensions. TLC, HPLC, and GC-MS analyses revealed the presence of IPyA, indole-3-ethanol, indole-3-lactic acid and its methyl ester, IAA and its methyl, and ethyl esters in the culture supernatant of the bacterium. IAAld was detected in the supernatant using sodium bisulfite and TLC. The results indicate that unlike gall-forming bacteria which can synthesize IAA by lAM, the indole-3-pyruvic acid pathway is the route for IAA biosynthesis in this beneficial strain of P. fluorescens.

• Proceedings of the Korean Biophysical Society Conference
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• 2002.06b
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• pp.28-28
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• 2002

Peptidoglycan is an extensively cross-linked polymer essential for the integrity of the bacterial cell wall. Many antibiotics act by disruption of its biosynthesis and assembly, several are targeted against the cytoplasmic enzymes that synthesize the key intermediate UDP-N-acetylmuramyl pentapeptide. One such drug is fosfomycin, which inactivates the first enzymes in this pathway, UDP-N-acetylglucosamine enopyruvyl transferase (murZ).(omitted)

• Journal of the Korea Society for Simulation
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• v.12 no.2
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• pp.45-53
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• 2003

This paper presents a retargetable compiled assembly simulation technique for fast ASIP(application specific instruction processor) simulation. Development of ASIP which satisfies design requirements in various fields of applications such as telecommunication, wireless network, etc. needs formal design methodology and high-performance relevant software environments such as compiler and simulator In this paper, we employ the architecture description language(ADL) named ${HiXR}^2$ to automatically synthesize an instruction-level compiled assembly simulator. A compiled simulation has benefit of time efficiency to interpretive one because it performs instruction fetching and decoding at compile time. Especially, in case of assembly simulation, instruction decoding is usually a time-consuming job(string operation), so the compiled simulation of assembly simulation is more efficient than that of binary simulation. Performance improvement of the compiled assembly simulation based on ${HiXR}^2$ is exemplified with an ARM9 architecture and a CalmRISC32 architecture. As a result, the compiled simulation is about 150 times faster than interpretive one.