• Journal of Electrochemical Science and Technology
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• v.10 no.4
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• pp.373-380
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• 2019

In this paper, we report the preparation of a flexible, self-standing and binder-free carbon nanotubes (CNTs) electrode with an electro-generated current collector. The copper current collector layer was electrodeposited on the backside of CNTs self-standing film obtained by a simple filtration process. The obtained CNTs-Cu assembly was used as a negative electrode in Li-ion batteries exhibiting good performance along with proving its applicability in flexible batteries.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.7
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• pp.754-760
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• 2008

In this paper, we introduce an RFID planar coil whose inductance does not change when it is attached on the metal surface. The coil is designed considering the inductance reduction on metal surface so that the inductance is the inverse times the reduction rate, and copper pour is placed in the bottom layer of the coil. This coil configuration is very simple and effective in constructing RFID systems for managing objects with metal surface because it prevents inductance reduction on metal surface.

• Tribology and Lubricants
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• v.36 no.6
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• pp.385-390
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• 2020

It rains heavily, such as long rain and typhoons, during a typical rainy season in Korea. In this season, several fuel contamination accidents by water and vehicular problems caused by water contaminated fuel occur. Many research groups have studied the effects of water contaminated fuel on vehicles and environment. However the characteristics of water contaminated fuel have not been studied. In this study, we prepared diesel samples with a constant ratio of water (0~30 volume %) using an emulsifier. Then, we analyzed these diesel samples for their representative fuel properties. In the analytical results, diesel with 30% water showed an increase in fuel properties such as density (823→883 kg/㎥), kinematic viscosity (2.601→6.345 ㎟/s), flash point (47→56℃), pour point (-22→2℃), CFPP (cold filter plugging point) (-17→20℃) and copper corrosion number (1a→2a). The low temperature characteristics, such as low pour point and CFPP, blocks the fuel filter in the cold season. In addition, water contaminated diesel decreases lubricity (190→410 ㎛) under high frequency reciprocating rig (HFRR) and derived cetane number (54.81→34.25). The low lubricity of fuel causes vehicle problem such as pump and injector damage owing to severe friction. In addition, the low cetane diesel fuel increases exhaust gases such as NOx and particulate matters (PM) owing to incomplete combustion. This study can be used to identify the problems caused by water contamination to vehicle and fuel facilities.