• Title/Summary/Keyword: carbon nano-tube

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Application of Carbon Naotube to the Electron Gun of the Cathode Ray Tube (탄소 나노 튜브의 음극선관용 전자총 응용)

  • Ju, Byeong-Gwon;Jang, Yun-Taek;Lee, Yun-Hui
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.51 no.3
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    • pp.121-124
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    • 2002
  • CNTs(Carbon Nano Tube) were employed as an electron source in electron-gun of CRT(Cathode-Ray Tube). The CNTs were grown on the Si substrates and the electron gun by LP-CVD(Low Pressure-Chemical Vapor Deposition). Their physical and field emission property satisfied the requirements of the electron gun of CRT. The fabricated electron gun was inserted into 19 inch-sifted CRT and its operating properly was evaluated for practical usage.

Methane hydrate formation Using Carbon Nano Tubes (탄소나노튜브를 이용한 메탄 하이드레이트 형성)

  • Park, Sung-Seek;Seo, Hyang-Min;Kim, Nam-Jin
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.549-552
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    • 2009
  • Methane hydrate is crystalline ice-like compounds which formed methane gas enters within water molecules composed cavity at specially temperature and pressure condition, and water molecule and each other from physically-bond. $1m^3$ hydrate of pure methane can be decomposed to the maximum of $172m^3$ at standard condition. If these characteristics of hydrate are reversely utilized, natural gas is fixed into water in the form of hydrate solid. Therefore the hydrate is considered to be a great way to transport and store natural gas in large quantity. Especially the transportation cost is known to be 18~24% less than the liquefied transportation. However, when methane hydrate is formed artificially, the amount of consumed gas is relatively low due to a slow reaction rate between water and methane gas. In this study, for the better hydrate reaction rate, there is make nano fluid using ultrasonic dispersion of carbon nano tube. and then, Experiment with hydrate formation by nano fluid and methane gas reaction. The results show that when the carbon nano tubes of 0.004 wt% was added to pure water, the amount of consumed gas was about 300% higher than that in pure water and the hydrate formation time decreased.

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A Study on Piezoresistive Characteristics of Smart Nano Composites based on Carbon Nanotubes for a Novel Pressure Sensor (압력센서 개발을 위한 탄소 나노 튜브 기반 지능형 복합소재 전왜 특성 연구)

  • Kim, Sung Yong;Kim, Hyun Ho;Choi, Baek Gyu;Kang, In Hyuk;Lee, Ill Yeong;Kang, In Pil
    • Journal of Drive and Control
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    • v.13 no.1
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    • pp.43-48
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    • 2016
  • This paper presents a preliminary study on the pressure sensing characteristics of smart nano composites made of MWCNT (multi-walled carbon nanotube) to develop a novel pressure sensor. We fabricated the composite pressure sensor by using a solution casting process. Made of carbon smart nano composites, the sensor works by means of piezoresistivity under pressure. We built a signal processing system similar to a conventional strain gage system. The sensor voltage outputs during the experiment for the pressure sensor and the resistance changes of the MWCNT as well as the epoxy based on the smart nano composite under static pressure were fairly stable and showed quite consistent responses under lab level tests. We confirmed that the response time characteristics of MWCNT nano composites with epoxy were faster than the MWCNT/EPDM sensor under static loads.

A study on Nano-convergence material technology of semiconductive flame retardant compound to improve impact resistance and electrical properties (내충격성 및 전기적 특성 향상을 위한 반도전성 난연컴파운드의 나노융복합 소재기술에 대한 연구)

  • Han, Jae-Gyu;Jeon, Geun-Bae;Park, Dong-Ha
    • Journal of the Korea Convergence Society
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    • v.12 no.1
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    • pp.193-198
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    • 2021
  • In this study, a nano-convergence material technology that can satisfy the superior impact resistance and electrical properties of the semiconducting flame retardant compound used in the Oversheath layer of Extra-high voltage cables was studied. When some of the carbon black used in the semiconducting flame-retardant compound was replaced with CNT (carbon nano tube), the change in physical properties was analyzed. Through the application of carbon nanotubes with remarkably excellent electrical properties, even a small amount of conductive filler formulations can provide superior electrical properties. In addition, as the total filler amount is reduced based on the compound, the workability is improved, and in particular, flexibility and impact resistance are improved, which is expected to contribute to the improvement of the durability of the cable.

Effect of Conductive Additives on $FeS_2$ Cathode ($FeS_2$ 양극에 미치는 전도성 첨가제의 영향)

  • Choi, Yu-Song;Cheong, Hae-Won;Kim, Ki-Youl;Cho, Sung-Baek
    • Journal of the Korea Institute of Military Science and Technology
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    • v.15 no.2
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    • pp.224-230
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    • 2012
  • Thermal batteries have excellent mechanical robustness, reliability, and long shelf life. Due to these characteristics as well as their unique activation mechanism, thermal batteries are widely adopted as military power sources. Li(Si)/$FeS_2$ thermal batteries, which are used mostly in these days, use LiCl-KCl and LiBr-LiCl-LiF as molten salt electrolyte. However, it is known that Li(Si)/$FeS_2$ thermal batteries have high internal resistance. Especially, $FeS_2$ cathode accounts for the greater part of internal resistance in unit cell. Many efforts have been put into to decrease the internal resistance of thermal batteries, which result in the development of new electrode material and new electrode manufacturing processes. But the applications of these new materials and processes are in some cases very expensive and need complicated additional processes. In this study, internal resistance study was conducted by adding carbon black and carbon nano-tube, which has high electron conductivity, into the $FeS_2$ cathode. As a results, it was found that the decrease of internal resistance of $FeS_2$ cathode by the addition of carbon black and carbon nano-tube.

A study on design for animal X-ray detector using CFRP CNT panel (CFRP CNT 패널을 적용한 동물용 X-ray 디텍터 디자인에 관한 연구)

  • Lee, Suk-Hyun;Kim, Hyun-Sung;Kang, Seung-Min
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.30 no.6
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    • pp.264-270
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    • 2020
  • Design was developed through user-oriented service design methodology and survey was conducted on material selection criteria for prototype production to select CFRP (Carbon Fiber Reinforced Plastics) CNT (Carbon Nano Tube), which was applied to animal X-ray detector panel to design product and develop prototype. Completed prototype with the application of CFRP CNT panel was tested in drop test, frontal external pressure test, and dustproof/waterproof performance to confirm that it can be utilized as a portable animal X-ray detector used in outdoor environment.

A Study on Carbon Nano Materials as Conductive Oilers for Microwave Absorbers (전자파 흡수체를 위한 전도성 소재로서의 탄소나노소재의 특성에 대한 연구)

  • Lee, Sang-Kwan;Kim, Chun-Gon;Kim, Jin-Bong
    • Composites Research
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    • v.19 no.5
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    • pp.28-33
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    • 2006
  • In this paper, we have studied the complex permittivities and their influence on the design of microwave absorbers of E-glass fabric/epoxy composite laminates containing three different types of carbon-based nano conductive fillers such as carbon black (CB), carbon nano fiber (CNF) and multi-wall nano tube (MWNT). The measurements were performed fur permittivities at the frequency band of 0.5 GHz$\sim$18.0 GHz using a vector network analyzer with a 7 mm coaxial air line. The experimental results show that the complex permittivities of the composites depend strongly on the natures and concentrations of the conductive fillers. The real and imaginary parts of the complex permittivities of the composites were proportional to the filler concentrations. But, depending on the types of fillers and frequency band, the increasing rates of the real and imaginary parts with respect to the filler concentrations were all different. These different rates can have an effect on the thickness in designing the single layer microwave absorbers. The effect of the different rates at 10 GHz was examined by using Cole-Cole plot; the plot is composed of a single layer absorber solution line and measured permittivities from these three types of composites. Single layer absorbers of 3 different thicknesses using carbon nano materials were fabricated and the -10 dB band of absorbing performances were all about 3 GHz.

A study of Physically Implanted Surface Islands by direct Nd:YAG Laser Beam Irradiation

  • Oh, Chang-Heon;Cheon, Suyoung;Lim, Changjin;Lee, Jeongjun;Jeon, Jihyun;Kim, Kyoung-Kook;Chung, Chan-Moon;Cho, Soohaeng
    • Applied Science and Convergence Technology
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    • v.26 no.4
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    • pp.66-69
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    • 2017
  • Physically implanted surface islands of Nano Carbon Tube (NCT) and ${\alpha}-F_2O_3$ particles have been produced on Al-doped ZnO (AZO)/glass surfaces by simple and direct ND:YAG laser beam irradiation. Sheet resistance of the reconstructed surface increased by about 3.6% of over AZO. Minimal surface damage can be repaired by ND:YAG laser beam irradiation in conjunction with proper impurities. Implanted islands of NCT, which are considered to be a good conductive impurity, on AZO increased the sheet resistance by about 1.8%, while implanted islands of ${\alpha}-F_2O_3$, an insulating impurity, on AZO increased sheet resistance by about 129% compared with a laser beam treated AZO. This study provides insight regarding surface implantations of nanowires and micro-circuits, doping effects for semiconductors and optical devices, surface area and impurity effects for catalysis.