통합 검색 | Korea Science

Park, Jae-Jun
- Transactions on Electrical and Electronic Materials
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- 제13권5호
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- pp.248-251
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- 2012
In order to develop a high voltage insulation material, epoxy/micro-silica composites (EMC) and epoxy/micro-silica/nano-silica composites (EMNC) with three different particle sizes in ${\mu}m$ and one particle size in nm were prepared and their tensile and flexural tests were carried out and the data was estimated by Weibull statistical analysis. The tensile strength of the neat epoxy was 82.8 MPa and those of the EMCs were larger than that of the neat epoxy, and they were much more advanced by the addition of 10 nm sized nano-silica to the EMCs. Flexural strength showed the same tendency of the tensile strength. As the micro-particle size decreased, tensile and flexural strength increased.
https://doi.org/10.4313/TEEM.2012.13.5.248 인용 PDF KSCI

이의주
- 한국가시화정보학회지
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- 제2권1호
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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.
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정재희;박형호;김상수
- 대한기계학회:학술대회논문집
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- 대한기계학회 2004년도 춘계학술대회
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- pp.1510-1515
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- 2004
The effects of additive ions on the generation of metallic nanoparticles were evaluated using a corona induced supersonic nozzle. Applying the corona discharge to the nanoparticle generator, a tungsten needle and the supersonic nozzle are used as an anode electrode and a cathode electrode respectively. The corona ions act as nuclei for the silver vapor condensation. The ion density was controlled precisely as varying the applied voltage between electrode and nozzle. The mean diameter of the silver particle decreases as the ion density increases. However, the number concentration of the silver particle tended to increase with the ion density. The size distribution is more uniform as the ion density increases.
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Asakuma, Y.;Takahashi, S.;Saptoro, A.;Maeda, Y.;Araki, N.
- 한국입자에어로졸학회지
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- 제11권3호
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- pp.77-85
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- 2015
A Belousov-Zhabotinsky reaction in a liquid-liquid system under microwave radiation was observed under non-stirring conditions. To control this non-equilibrium reaction, nano-particle, which is active under microwave irradiation, was added to the solution. Color changes of the solution during the oscillatory reaction were found to be influenced by the irradiation power although the droplet temperature was equal to the temperature of surrounding oil. During the irradiation, the period of oscillation became shorter because the reaction rate was faster. It could also be observed that there is possibility to eliminate oscillatory behaviors of the reaction using higher power of microwave. The possibility of controlling non-linear reaction using microwave was shown since microwave can easily travel through oil phase and reach water phase.
https://doi.org/10.11629/jpaar.2015.11.3.077 인용 PDF

Chang Ho Jung;Wang Yongsheng;Suh Kwang-Jong;Son Chang-Sik
- 한국재료학회지
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- 제15권7호
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- pp.431-434
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- 2005
To investigate the dependences of the absorption spectrum and electronic structure properties on the ZnO nano-particle size, ZnO nanocrystals were synthesized by a sol-gel method. The absorption onset peak exhibits a systematic blue-shift with decreasing particle size due to the quantum confinement effect, as well as, with decreasing $Zn^{2+}$ concentration. The increase of particle size is mainly controlled by coarsening and aggregation step during the nucleation and growth of ZnO nano-particles. The onset absorption spectrum of ZnO colloids changes from 310 to 355 nm as $Zn^{2+}$ concentration increases from 0.01 to 0.1 mole. The average particle size as a function of aging- time can be determined from the absorption spectra. The freshly prepared nanocrystal size was about 2.8nm.
https://doi.org/10.3740/MRSK.2005.15.7.431 인용 PDF KSCI