• Title/Summary/Keyword: Carbon Nanotube

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Modeling, Simulation, and Control of a Polyaniline/Carbon-Nanotube Polymer Actuator (폴리아닐린/탄소나노튜브 폴리머 액츄에이터의 모델링, 시뮬레이션 및 제어)

  • Sohn, Ki-Won;Yi, Byung-Ju;Kim, Sean-Jeong;Kim, In-Young;Kim, Sun-I.
    • Journal of Biomedical Engineering Research
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    • v.28 no.3
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    • pp.348-354
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    • 2007
  • Polymer actuators, which are also called as smart materials, change their shapes when electrical, chemical, thermal, or magnetic energy is applied to them and are useful in wide variety of applications such as microelectromechanical systems (MEMS), machine components, and artificial muscles. For this study, Polyaniline/carbon-nanotube polymer actuator that is one of electroactive polymer actuators was prepared. Since the nonlinear phenomena of hysteresis and a step response are essential considerations for practical use of polymer actuators, we have investigated the movement of the Polyaniline/carbon-nanotube polymer actuator and have developed an integrated model that can be used for simulating and predicting the hysteresis and a step response during actuation. The Preisach hysteresis model, one of the most popular phenomenological models of hysteresis, were used for describing the hysteretic behavior of Polyaniline/carbon-nanotube polymer actuator while the ARX method, one of system identification techniques, were used for modeling a step response. In this paper, we first expain details in preparation of the Polyaniline/carbon-nanotube polymer then present the mathematical description of our model, the extraction of the parameters, simulation results from the model, and finally a comparison with measured data.

The use of Interfacial Graphene to Carbon nanotube Point emitter for Field Emission Electric Propulsion (그래핀을 이용한 탄소나노튜브 전계방출소자 계면 개질 및 전자 추진계 응용)

  • Lee, Jeong Seok;Kang, Tae June;Kim, Dae Weon;Kim, Yong Hyup
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.40 no.11
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    • pp.1004-1009
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    • 2012
  • Carbon nanotube are nanostructure with extraordinary field emission properties like high current density, low driving voltage and long time stability, because of their high electrical conductivity, high aspect ratio for geometrical field enhancement and superior thermal stability. But, there is some problem to mate metal and carbon nanotube, we have resolved this problem by using interfacial graphene. This approach takes advantage of superior electric and thermal conductivity between metal and carbon nanotube and shows superior performance compared to the existing field emitters. This result shows that such a carbon nanotube emitter in a stage where it can be used for Field Emission Electric Propulsion (FEEP).

Supercapacitors using Pure Single-walled Carbon Nanotubes

  • Tanaike, Osamu;Futaba, Don N.;Hata, Kenji;Hatori, Hiroaki
    • Carbon letters
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    • v.10 no.2
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    • pp.90-93
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    • 2009
  • The excellent and characteristic capacitor performance of pure single-walled carbon nanotubes (SWNTs), which differ from conventional activated carbon electrodes, is reported. SWNTs with little bundling showed higher specific capacitance than activated carbons. High operating voltage can be expected for pure SWNTs without metal contamination and graphene edge structure.

Nano Carbon Material Based Electrochemical Actuators (탄소 나노 재료 기반의 전기-화학적 구동기)

  • Cha, Ju-Young;Kang, In-Pil
    • Journal of the Korean Society for Precision Engineering
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    • v.28 no.11
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    • pp.1251-1258
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    • 2011
  • With the help of nanoscale materials like carbon nanotube (CNT), there is the potential to develop new actuators that will provide higher work per cycle than previous actuator technologies, and generate much higher mechanical strength. In this study, the electrochemical actuation characteristics of nano carbon materials were experimentally studied to develop electrochemical actuators. The electrochemical actuators were composed of aqueous NaCl electrolyte and their actuating electrodes were made of multi-walled carbon nanotube (MWCNT)/polystyrene composite and graphene respectably. Actuation is proportional to charging transfer rate, and the electrolysis with an AC voltage input has very complex characteristics. To quantify the actuation property, the strain responses and output model were studied based on electrochemical effects between the nano carbon films and the electrolyte.

Cycling Performance of Supercapacitors Assembled with Polypyrrole/Multi-Walled Carbon Nanotube/Conductive Carbon Composite Electrodes

  • Paul, Santhosh;Kim, Jae-Hong;Kim, Dong-Won
    • Journal of Electrochemical Science and Technology
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    • v.2 no.2
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    • pp.91-96
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    • 2011
  • Polypyrrole (PPy)/multi-walled carbon nanotube (MWCNT)/conductive carbon (CC) composites are synthesized by the chemical oxidative polymerization method. The morphology analysis of the composite materials indicates uniform coating of PPy over MWCNTs and conductive carbon. The electrochemical performances of PPy/MWCNT/CC composites with different compositions are evaluated in order to optimize the composition of the composite electrode. Galvanostatic chargedischarge measurements and electrochemical impedance spectroscopy studies prove the excellent cycling stability of the PPy/MWCNT/CC composite electrodes.

In-situ rf treatment of multiwall carbon nanotube with various post techniques for enhanced field emission

  • Ahn, Kyoung-Soo;Kim, Jun-Sik;Kim, Ji-Hoon;Kim, Chae-Ok;Hong, Jin-Pyo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.859-862
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    • 2003
  • Well-aligned multiwall carbon nanotubes (MWCNTs) were prepared at low temperature of 400 $^{\circ}C$ by utilizing a radio frequency plasma-enhanced chemical vapor deposition (rf-PECVD) system. The MWCNTs were treated by an external rf plasma source and an ultra-violet laser in order to modify structural defect of carbon nanotube and to ablate possible contamination on carbon nanotube surface. Structural properties of carbon nanotubes were investigated by using a scanning electron microscopy (SEM), Raman spectroscopy, Fourier transformer Infrared spectroscopy (FTIR) and transmission electron microscope (TEM). In addition, the emission properties of the MWNTs were measured for the application of field emission display (FED) in near future. Various post treatments were found to improve the field emission property of carbon nanotubes.

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The Characteristic of Prepared Electrode Catalyst and MEA using CNF and CNT (CNT 및 CNF를 이용하여 제조된 전극 촉매 및 막 전극 접합체의 특성)

  • 임재욱;최대규;류호진
    • Journal of the Microelectronics and Packaging Society
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    • v.11 no.1
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    • pp.59-64
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    • 2004
  • The performance of fuel cell electrode depends on the characteristics of the catalyst support material. This paper deals with the use of CNF(carbon nanofibre) and CNT(carbon nanotube) as platinum catalyst support. The CNF and CNT were synthesized with catalyst treated by mechanochemical process and were prepared by chemical vapor deposition (CVD) method. The platinum supported on CNF and CNT for polymer electrolyte membrane fuel cell (PEMFC) application. In result, the best I-V characteristic was verified by the prepared MEA(membrane electrode assembly) from twisted CNF that had a diameter of 65 nm.

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Carbon nanotube antennas analysis and applications: review

  • El-sherbiny, Sh.G.;Wageh, S.;Elhalafawy, S.M.;Sharshar, A.A.
    • Advances in nano research
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    • v.1 no.1
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    • pp.13-27
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    • 2013
  • Carbon nanotube characterized by additional inductive effect as compared with the traditional conductors like copper wires of the same size. Consequently, carbon nanotubes have high characteristic impedance and slow wave propagation in comparison with traditional conductors. Due to these characteristics, carbon nanotubes can be used as antenna. In view of this, we describe and review the present research progress on carbon nanotube antennas. We present different analysis models and results which are developed to investigate the characteristics of CNT antennas. Then we conclude by summarizing the characteristics of CNT antennas and specifying the operating frequency limit.

Molecular Dynamic Simulation of The Temperature-Dependent Single Wall Carbon Nanotube (온도변화에 따른 탄소 나노튜브의 분자 동역학 시뮬레이션)

  • 문원하;강정원;이영직;박수현;황호정
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.913-916
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    • 1999
  • Recent developments of carbon nanotubes are reviewed[1,2,3,4]. We use Tersoff carbon potential for bonded interactions[5] and Lennard-Jones 12-6 potential for non bonding interactions[6]to describe mechanical properties of the temperature-dependent armchair single wall carbon nanotube. At first we report that through defect number and bonding energy calculation, how single wall carbon nanutube is capped in the constant temperature. (300K, 2000K, 3000K, 4000K) At second, we perform MD simulation, which are performed on the energy optimized structure of carbon nanotube.

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Finite Element Modeling of a Carbon Nanotube Actuator (탄소나노튜브 엑츄에이터의 설계에서의 유한요소모델링 기법)

  • 김정택;현석정;김철
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.05a
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    • pp.559-562
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    • 2004
  • Carbon nanotube is a geometrical frame-like structure and the primary bonds between two nearest-neighboring atoms act like beam members, whereas an individual atom acts as the joint of the related beam members. The sectional property parameters of these beam members are obtained from molecular mechanics. Computations of the elastic deformation of single-walled carbon nanotubes reveal that the Young's moduli of carbon nanotubes vary with the tube diameter and are affected by their helicity. With increasing tube diameter, the Young's moduli of carbon nanotubes approach the Young's modulus of graphite.

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