• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1777-1780
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• 2012

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.150.1-150.1
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• 2005

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.499-500
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• 2010

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1591-1593
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• 2008

The tubular field emission lamp (FEL) was developed using a wire type carbon-nano-structure emitter called CNX The luminous efficiency of the tubular FEL (diode type, diameter: ${\varphi}15.5mm$, length: 200mm) has already achieved around 45lm/W and we expect to achieve over 60lm/W within the year.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.245-246
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• 2006

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.5
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• pp.517-521
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• 2012

Carbon nanotubes (CNTs) have been regarded as a promising material for the fabrication of flexible conductors such as transparent electrodes, flexible heaters, and transparent speakers. In this study, a multiwalled carbon nanotube (MWCNT) film was deposited on a polyethylene terephthalate (PET) substrate using a spraying technique. MWCNTs were dispersed in water using sodium dodecyl sulfate (SDS). To evaluate the effect of the weight ratio between SDS and MWCNTs on the electromechanical properties of the film, direct tensile tests and optical strain measurement were conducted. It was found that the CNT film hardly affected the mechanical behavior of CNT/PET composite films, while the electrical behavior of the CNT film was strongly affected by the SDS concentration in the CNT film. The electrical resistance of CNT/PET films gradually increased with the strain applied to the PET substrate, even up to a large strain that ruptured the substrate.

• Applied Chemistry for Engineering
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• v.29 no.5
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• pp.549-555
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• 2018

In this study, the electrochemical properties of nano-Pb/activated carbon (nano-Pb/AC) composites and electrolyte additives were examined to improve the performance of ultra batteries. Physical properties of the prepared nano-Pb/AC composites were analyzed using FE-SEM, TEM, XPS and BET. The electrochemical performances of ultra batteries were performed by cycle, rate performance and impedance tests. The cycling performance of nano-Pb/AC (Pb : 9 wt%) coated ultra battery increased by 150% with respect to the lead acid one, and the discharge specific capacity increased by 119-122% for 1-5 C rate tests. As a result of the impedance test, it was confirmed that the internal resistance decreased as the nano lead content increased. The cycle performance of the ultra battery containing 0.45 vol% electrolyte additives showed 140% longer than that of no electrolyte additives.

• Advances in nano research
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• v.2 no.4
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• pp.199-210
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• 2014

Carbon nanotubes have exceptional mechanical, thermal and electrical properties, and are considered for high performance structural and multifunctional composites. In the present study, the natural frequencies of aligned single walled carbon nanotube (CNT) reinforced composite beams are obtained using shear deformable composite beam theories. The Ritz method with algebraic polynomial displacement functions is used to solve the free vibration problem of composite beams. The Mori-Tanaka method is applied to find the composite beam mechanical properties. The continuity conditions are satisfied among the layers by modifying the displacement field. Results are found for different CNT diameters, length to thickness ratio of the composite beam and different boundary conditions. It is found that the use of smaller CNT diameter in the reinforcement element gives higher fundamental frequency for the composite beam.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.1
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• pp.27-32
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• 2004

The diamond-like carbon (DLC) films were deposited on the Si (100) wafer by a rf-PECVD method as a function of the mixture rate of methane-hydrogen gas and bias voltage. The bonding structure and mechanical properties of these deposited DLC films were investigated using FT-IR, Raman, and nano-indenter. The deposition rates of DLC films increased with increased flow rate of methane in the gas mixtures and increased bias voltage. The $sp^3/sp^2$ bonding ratio of carbon in thin film and the hardness increased with increasing flow rate of hydrogen in the gas mixtures and increasing bias voltage.

• Carbon letters
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• v.11 no.4
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• pp.298-303
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• 2010

A method of functionalization of multi-walled carbon nanotube (MWNT) at room temperature using dry ozone gas is described. The resulting MWNT were characterized by Fourier transform infrared, x-ray photoelectron spectroscopy, and scanning electron microscopy. Combined to these analyses and solubility in liquids, it could be concluded that the dry ozone gas exposure introduces polar functional groups such as carboxylic groups to MWNT similar to acidic modification of MWNT. Particularly, the stable dispersion of MWNT in water after ozone treatment above a critical level could be obtained, implying potential bio-application. The hydrophilic functional groups on the MWNT introduced by ozone oxidation were helpful in improving the interaction with functional groups in PA6 such as $-NH_2$ and -CONH- resulting in improved mechanical properties.