• Title/Summary/Keyword: Conducting

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A Study on the Characteristics of the Hybrid Carbons Filled Poly(Phenylene Sulfide) Composite Bipolar Plates of Fuel Cell (하이브리드카본이 충전된 Poly(Phenylene Sulfide) 복합재 연료전지 분리판 특성 연구)

  • Kim, Nam-Hoon;Park, Ok-Kyung;Lee, Chang-No;Lee, Joong-Hee
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.172-175
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    • 2009
  • A bipolar plate is an important component in a fuel cell in the sense of cost and weight. This study aimed at developing highly conductive, lightweight, and low cost bipolar plates. Hybrid carbons filled poly(phenylene sulfide)(PPS) composite bipolar plates were prepared by using the compression molding technique. Various types and amounts of conducting carbon fillers such as graphite, carbon black, carbon fibers, and carbon nanotubes (CNTs) were adopted for the composites. Electrical conductivity and mechanical properties of the composites were measured in order to investigate effects of each components of fillers. When the graphite is only used as a conducting filler, the electrical conductivity of the composites increases with increasing the content, but the flexural strength decreases dramatically. However, for CNTs and carbon fibers, the flexural strength initially increases and then decreases with increasing the amount of the conducting fillers. The amount of graphite corresponding to the peak of flexural strength was moved to lower content with increasing the amount of CNTs or carbon fiber. When hybrid conducting fillers such as fibrous and particulate fillers were used, the synergy effect in mechanical and electrical properties was observed.

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Electrochromism of Various Conducting Polymers with Enhanced Functionality (기능성을 향상시킨 다양한 전도성 고분자의 전기 변색 현상)

  • Ko Heung-Cho;Moon Bong-Jin;Lee Hoo-Sung
    • Polymer(Korea)
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    • v.30 no.5
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    • pp.367-372
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    • 2006
  • Electrochromic materials based on conducting polymers with pendant chromophores as well as their electrochromic properties are described. The conducting polymers described aye polypyrrole, polythiophene, poly(3,4-ethylenedioxythiophene), poly (cyclopentadithiophene), and poly (1,4-bis [2- (3,4-ethylenedioxy) thienyl] benzene). The chromophores described are viologen and perylenetetra-carboxylic diimide. When the wavelength ranges of absorption of the conducting polymer and the chromophore aye not overlapping, multiple electrochromism was achieved. When the wavelength ranges are largely overlapping, higher contrast was achieved. An easy method for prediction of the film thickness for maximum contrast of a given electrochromic material is also described.

Research Related Activities and Its Related Factors in Clinical Nurses (임상간호사의 연구관련 활동 실태와 관련요인)

  • Yang Young-Hee;Gu Mee-Ock
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.12 no.3
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    • pp.421-429
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    • 2005
  • Purpose: This study was don(B to describe research-related activities and attitudes toward research, barriers to and support needs for undertaking research in clinical nurses. Method: Data were collected by a questionnaire from 238 clinical nurses with over one year clinical experience working at 2 university hospitals. Results: Research related activities included courses or lecture about Nursing Research 85.7%, journal reading at least once every 2 to 3 months 30.0%, memberships in academic societies 29.4%, participation in academic conferences 45.0%, conducting research 45.4%, research utilization 24.6%. The score for attitudes toward research was 3.08(range 1-5). The score of barriers to undertaking research was 3.37(1-5) and the score for support needs for undertaking research 4.14(1-5). Attitudes toward research significantly correlated with barriers to undertaking research(r=.- 36, p=.000). Barriers to undertaking research significantly correlated with support needs for conducting research(r=.23, p=.000). Nurses with experience in conducting research had more negative attitudes toward research(t=-2.130, p=0.034) and more barriers to undertaking research than those without experience in conducting research (t=2.194, p=0.029). Conclusion: These results suggest that it is necessary to increase positive attitudes toward research in clinical nurses and nursing organizations need to provide strong supports for nurses conducting research.

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Effects on Electrochemical Performances of Conducting Agents for Lithium-ion Batteries (리튬이온전지용 Conducting Agents의 전기화학적 성능에 미치는 영향)

  • Lee, Chang-Woo;Lee, Mi-Sook;Moon, Seong-In;Kim, Young-Gyu;Kim, Byung-Hwa;Kim, Dong-Hoon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.593-594
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    • 2005
  • Lithium-ion batteries have used the layered $LiCoO_2$ materials as cathodes, but Co is relatively toxic and expensive. In this regard, the spinel $LiMn_2O_4$ has become appealing because manganese is inexpensive and environmentally benign. In general, cathodes for lithium ion batteries include carbon as a conductive agent that provides electron transfer between the active material and the current collector. In this work, we selected Acetylene Black and Super P Black as conducting agents, and then carried out comparative investigation for the performances of the cells using different conducting agents with different particle size. As a consequence, Li/$LiMn_2O_4$ cells with Super P Black show better electrochemical performances than those with Acetylene Black.

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Synthesis of Mesostructured Conducting Polymer-Carbon Nanocomposites and Their Electrochemical Performance

  • Choi, Moon-Jung;Lim, Byung-Kwon;Jang, Jyong-Sik
    • Macromolecular Research
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    • v.16 no.3
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    • pp.200-203
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    • 2008
  • A conducting polymer layer was introduced into the pore surface of mesoporous carbon via vapor infiltration of a monomer and subsequent chemical oxidative polymerization. The polypyrrole, conducting polymer has attracted considerable attention due to the high electrical conductivity and stability under ambient conditions. The mesoporous carbon-polypyrrole nanocomposite exhibited the retained porous structure, such as mesoporous carbon with a three-dimensionally connected pore system after intercalation of the polypyrrole layer. In addition, the controllable addition of pyrrole monomer can provide the mesoporous carbon-polypyrrole nanocomposites with a tunable amount of polypyrrole and texture property. The polypyrrole layer improved the electrode performance in the electrochemical double layer capacitor. This improved electrochemical performance was attributed to the high surface area, open pore system with three-dimensionally interconnected mesopores, and reversible redox behavior of the conducting polypyrrole. Furthermore, the correlation between the amount of polypyrrole and capacitance was investigated to check the effect of the polypyrrole layer on the electrochemical performance.

Electromechanical actuators using conducting polymer composite films (전도성 복합재료 필름을 응용한 Electromechanical actuators)

  • Chang Jin hee;Kim Suk Young;Im Seung Soon
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.04a
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    • pp.303-304
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    • 2003
  • Conducting polymers show several unique features, wherein electrical and optical properties change drastically during electrochemical reaction. By making use of these phenomena, several electronic devices have been fabricated, for instance, electrochromic displays, rechargeable batteries and electroplasticity memory devices. Electromechanical actuators using conducting polymers have been proposed by Baughman et. al [1]. (omitted)

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Preparation and applications of electrically conducting fabrics

  • Lee, Jun-Young;Jinsoo Joo;Lim, Jeong-Ok
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.10a
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    • pp.25-26
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    • 2003
  • Electrically conducting polymers such as polypyrrole(PPy) or poly(3,4-ethylene dioxythiophene)(PEDOT) were sequentially polymerized chemically and electrochemically on various kinds of woven fabrics, giving rise to the fabrics with high electrical conductivity. The specific volume resistivity of the fabric prepared in this study was extremely low as 0.2 $\Omega$-cm. We figured out the electrically conducting fabrics were practically useful for many applications such as an EMI shielding material, a flexible surface heating element or a strain sensor for large deformation.

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Incoherent Tomography for Conducting Cylinder by Using Single-Frequency Time-Harmonic Source (단일 주파수 시간조화 신호원을 사용한 도체기둥의 incoherent 단면영상법)

  • 강진섭;라정웅
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.35D no.1
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    • pp.1-7
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    • 1998
  • In this paper, an incoherent imaging of a conducting cylinder illuminated by the single-frequency time-harmonic plane wave is obtained via the back-projections of the intensity patterns of the forward total electric field scattered from this object in the circular rotational measurement configuration. The pheonmenon that interference fringes generated in the itesity patterns is removed in the back-projection process is interpreted numerically. This imaging method is validated by imagining conducting circular cylinders and the conditions to ge beter image are investigated.

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Conducting Polyaniline-Titanium Dioxide Nanocomposites Prepared by Inverted Emulsion Polymerization

  • Karim, Mohammad Rezaul;Lee, Hyun-Woo;Cheong, In-Woo;Park, Sung-Min;Oh, Weon-Tae;Yeum, Jeong-Hyun
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2009.03a
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    • pp.158-159
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    • 2009
  • Conducting polyaniline (PAni)-titanium dioxide ($TiO_2$) nanocomposites have been synthesized by the inverted emulsion polymerization method. The resultant PAni-$TiO_2$ nanocomposites are characterized with their structural, morphological, conducting and optical properties.

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The Electric Field Analysis with Conducting Particle between Coaxial Cylindrical Electrodes in $SF_6$ Gas ($SF_6$ 가스 동축원통전극에서 금속이물 존재시의 전계해석)

  • 조국희;곽희로
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 1999.11a
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    • pp.168-171
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    • 1999
  • This paper describes the influence of conducting particle within the coaxial cylindrical electrodes gap under alternating voltage condition investigated using charge simulation method. If the conducting particles precent in the gas insulated system, they can cause decrement of breakdown voltage. Thus, three dimensions computations of electric fields and electrostatic forces have been carried out according to particle location. The results show a good agreement with those of outside country, which can offer a practical reference on the insulation design of domestic GIS.

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