• Textile Coloration and Finishing
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• v.22 no.1
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• pp.37-42
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• 2010

ABS/MWNT nanocomposites were prepared by using MWNT wrapped with SAN through melt compounding. Effect of wrapping of MWNT by SAN on the morphology, mechanical and electrical properties of ABS/MWNT were analyzed. It was found that SAN could wrap MWNT effectively indicated by the increased thickness after wrapping, which is presumably due to helical structure of polyacrylonitrile component in a block copolymer of SAN. MWNT was observed to be dispersed more evenly in ABS matrix by SAN wrapping, which resulted in improved tensile properties of the composites. On the other hand, there was little effect on the impact strength and electrical properties of ABS having inherently high impact strength.

• Textile Coloration and Finishing
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• v.20 no.4
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• pp.31-42
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• 2008

Tricrecyl phosphate(TCP)-containing polyurea microcapsules were prepared by interfacial polymerization using aromatic 2,4-toluene diisocyanate(TDI) and ethylenediamine(EDA) as wall forming materials. The effects of the protective colloids of polyvinylalcohol(PVA) and gelatin were investigated through experimentation. The mean size of prepared polyurea microcapsules was smaller and the surface morphology of the microcapsule prepared by the PVA as protective colloid was much smoother than the gelatin. As the concentration of protective colloid increased, the wall membrane of the polyurea microcapsules became more stable, the thermal stability of the wall membrane increased, the mean particle size became smaller, and the particle distribution was more uniform. PET containg microTCPs have a higher activation energy of decomposition, higher char content and lower heat of combustion.

• Journal of the Korean Society of Visualization
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• v.2 no.1
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• pp.12-17
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• 2004

The physical characteristics of soot near the soot inception point were investigated with various measurements. In-situ measurements of particle size and volume fraction were introduced based on time resolved laser-induced incandescence (TIRE-LII) and laser-induced ion mobility (LIIM). The one has more convenience and accuracy than conventional LII technique and the other works best for particle sizes of a few nanometers at high concentrations in a uniform concentration field. A complementary ex-situ measurement of particle size is nano differential mobility analyzer (Nano-DMA), which recently developed for measuring particle sizes between 2nm and 100nm and provides high-resolution size information for early soot. Particles will be also collected on transmission electron microscope (TEM) grids using rapid thermophoretic sampling and analyzed for morphology. These measurements will allow fresh and original insight into the characterizing soot inception process. The measured physical properties of incipient soot will clarify the controlling growth mechanism combined with chemical ones, and the dominant mechanism for soot modeling can be deduced from the information.

• Journal of Information Display
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• v.8 no.1
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• pp.14-17
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• 2007

The toner type paper-like display (PLD) has been developed with two polymer particles having opposite polarity composed of polymer, colorant and external additives (nano-sized silica). Nano-sized silica with triboelectric charge was used for the charge control agent (CCA) and influenced on the electrostatic properties of the silica-coated polymer particles. The surface morphology and the cohesiveness of silica-coated polymer particles were changed with the silica coating time. From these results, it was verified that the PLD cell using silica-coated particles (200 seconds) shows a good white appearance and low driving voltage.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.329-329
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• 2008

Silver nanoparticles were synthesized by polyol process and its particle size observed with TEM is about 20nm. Silver nanoparticle ink with metal content of 30wt% was prepared using solvent of ethanol and has low viscosity of 5cps (10rpm). This ink was printed by as ink-jet printer on Al2O3 and Silicone substrate. The resistivity and morphology of the printed film was investigated as a function of sintering termperature.

• Journal of Sensor Science and Technology
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• v.14 no.5
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• pp.297-301
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• 2005

Nanocrystalline SnO and $SnO_{2}$ powder have been prepared by hydrazine method. Sn-Hydrazine complex was formed by the reduction between aqueous $SnCl_{2}$ solution and hydrazine monohydrate. $SnO_{2}$ nano powder was prepared by the decomposition of Sn-Hydrazine complex at $450^{\circ}C$. When NaOH was added to Sn-hydrazine complex, SnO powder with nano-sheet morphology could be prepared. This can be attributed to the role of $OH^{-}$ ion as a reducing agent.

• Journal of Surface Science and Engineering
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• v.39 no.4
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• pp.153-159
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• 2006

Nanodiamond films were deposited on Si substrate by introducing a time dependent on/off modulation of $CH_4\;and\;O_2$ flows in a vertical-type microwave plasma enhanced chemical vapor deposition system. Surface morphology and diamond quality of the film were investigated as a function of the on/off modulation time interval. The diamond nucleation density on the substrate was enhanced under low temperature and low pressure condition. In addition, the diamond nucleation density was enhanced by increasing the on/off modulation time interval. Enhanced diamond quality was noticeable under the condition of a longer on/off modulation time interval. It was suggested that the nanodiamond nuclei formed the cluster formation.

• Nano
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• v.13 no.10
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• pp.1850114.1-1850114.7
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• 2018

Here we report an optimized hot-injection method and a phase transfer strategy for the synthesis of water-soluble $CuInS_2$ QDs with desired properties. The structure and morphology studies demonstrate that the resulting QDs are $CuInS_2$ tetragonal phase with well-defined facets. It is also found that the crystal size gradually increases with the increase of reaction temperature, while the surface of QDs with pre- and post-phase transfer is functionalized with hydrophobic and hydrophilic ligands, respectively. Spectroscopy measurements reveal the size-dependent optical properties of $CuInS_2$ QDs, demonstrating the quantum confinement effect in this system.

• Archives of Metallurgy and Materials
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• v.66 no.4
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• pp.991-995
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• 2021

In this paper, synthesize MoO₃ particles with various particle properties by control growth influence factors was mainly studied. The experimental conditions were established in molar ratio of Mo:urea and pH levels. The plate-type of MoO₃ particles were formed without proceeding any established conditions, but the rod-shape particles were formed by adjusting molar ratio of Mo:urea. Also, different ranges of the particle size were formed by adjusting experimental conditions. Through the results, it was confirmed that particles with a size in the range of 300 ~ 400 nm were obtained by adjusting precursor concentration and the micrometer size of particles were formed by increase pH levels. The properties of the particles formed accordingly by setting various factors that can affect the growth process of MoO₃ particle was analyzed as variables and the particle growth behavior was also observed.

• Korean Journal of Materials Research
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• v.21 no.12
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• pp.697-702
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• 2011

Two-dimensional (2D) nano patterns including a two-dimensional Bravais lattice were fabricated by laser interference lithography using a two step exposure process. After the first exposure, the substrate itself was rotated by a certain angle, $90^{\circ}$ for a square or rectangular lattice, $75^{\circ}$ for an oblique lattice, and $60^{\circ}$ for a hexagonal lattice, and the $90^{\circ}$ and laser incident angle changed for rectangular and the $45^{\circ}$ and laser incident angle changed for a centered rectangular; we then carried out a second exposure process to form 2D bravais lattices. The band structure of five different 2D nano patterns was simulated by a beam propagation program. The presence of the band-gap effect was shown in an oblique and hexagonal structure. The oblique latticed ZnO nano-photonic crystal array had a pseudo-bandgap at a frequency of 0.337-0.375, 0.575-0.596 and 0.858-0.870. The hexagonal latticed ZnO nano-crystallite array had a pseudo-bandgap at a frequency of 0.335-0.384 and 0.585-0.645. The ZnO nano structure with an oblique and hexagonal structure was grown through the patterned opening window area by a hydrothermal method. The morphology of 2D nano patterns and ZnO nano structures were investigated by atomic force microscopy and scanning electron microscopy. The diameter of the opening window was approximately 250 nm. The height and width of ZnO nano-photonic crystals were 380 nm and 250 nm, respectively.