• Carbon letters
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• 제3권4호
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• pp.210-218
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• 2002

Electrostatic spinnings were performed with the solutions of PAN/DMF to be nanofiber webs. The diameter of the fibers ranged from 200 nm to 1000 nm depending on the PAN concentration and on the applied DC voltage. The nanofibers were oxidatively stabilized and subsequently carbonized up to $1000^{\circ}C$ with carbonization yield of 40%. The bulk electric conductivity of the carbonized web increased form $6.8{\times}10^{-3}S/cm$ to 1.96 S/cm while the carbonizaton temperature increased from $700^{\circ}C$ to $1000^{\circ}C$.

• 한국염색가공학회지
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• 제28권2호
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• pp.77-91
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• 2016

Recently, the spun blend yarns with staple fibers and filaments are being developed in the spinning process using an air blowing and electrostatic spinning technology(cyclone) in order to enhance the soft feeling and the fine count spun blend yarn manufacturing competitiveness. In this study, the appropriate separation condition of polyester multifilament was examined according to the treatment condition of conductive agents and voltage on polyester multifilament in the newly developed cyclone spinning process. And it was investigated the physical properties and dyeability of the cyclone wool/polyester spun blend yarns and its wool composite fabrics in comparison with existing sirofil wool/polyester spun blend yarn and its fabrics. As the result, it is determined that the newly developed cyclone wool/polyester spun blend yarn applied fabrics has a superior quality level in terms of practicality.

• Korea-Australia Rheology Journal
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• 제15권1호
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• pp.1-7
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• 2003

A new method is introduced to build up organic/organic multilayer films composed of cationic poly(allylamine hydrochloride) (PAH) and negatively charged poly (sodium 4-styrenesulfonate) (PSS) using the spinning process. The adsorption process is governed by both the viscous force induced by fast solvent elimination and the electrostatic interaction between oppositely charged species. On the other hand, the centrifugal and air shear forces applied by the spinning process significantly enhances desorption of weakly bound polyelectrolyte chains and also induce the planarization of the adsorbed polyelectrolyte layer. The film thickness per bilayer adsorbed by the conventional dipping process and the spinning process was found to be about 4 ${\AA}$ and 24 ${\AA}$, respectively. The surface of the multilayer films prepared with the spinning process is quite homogeneous and smooth. Also, a new approach to create multilayer ultrathin films with well-defined micropatterns in a short process time is Introduced. To achieve such micropatterns with high line resolution in organic multilayer films, microfluidic channels were combined with the convective self-assembly process employing both hydrogen bonding and electrostatic intermolecular interactions. The channels were initially filled with polymer solution by capillary pressure and the residual solution was then removed by the .spinning process.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1615-1618
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• 1994

This paper studied the streaming electrification of the U.H.V. transformer with the spinning cylinder system, and compared and analyzed it with the conventional forced flowing system which uses a pump or gas for oil flowing. Also, accumulated surface voltage in its electrified material was measured with the electrostatic voltmeter, and the effect of insulation oil aging was measured. As results, in spinning cylinder system, characteristics of the streaming electrification to its rotational speed and oil temperature are same tendency as those of tile forced flowing system and it showed the spinning cylinder system is useful to study the streaming electrification. And, aging of insulation oil increases the electricity of streaming electrification at initial stage of aging.

• 한국입자에어로졸학회지
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• 제5권2호
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• pp.71-81
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• 2009

In this study, Nylon 6,6 electrospun (ES) nanofiber filter media were prepared at various spinning conditions. The ES filters tested had no intrinsic electrical charges. The ES filters were triboelectrically charged in the course of filter sample handling, and the charge was drastically decayed in a few hours. On the other hand, the corona charged melt blown filter media showed a permanent electrical charge. The electrical charge state of the ES filters was also examined by comparing collection efficiencies of ES filters for uncharged and charged aerosol particles.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.433-433
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• 2016

Carbon nanotubes (CNT) emitter has widely become an attractive mechanism that draws growing interests for cold cathode field emission. CNT yarns have demonstrated its potential as excellent field emitters. It was demonstrated that a small focal spot size was achieved by manipulating some electrical parameters, such as applied bias voltage at the mesh gate, and electrostatic focal lenses, geometrical parameters, such as axial distances of the anode, and the electrostatic focal lens from the cathode assembly, and the dimension of the opening of the electrostatic lens. Electrical-optics software was used to systematically investigate the behavior of the electron beam trajectory when the aforementioned variables were manipulated. The results of the experiment agree with the theoretical simulation results. Each variable has an individual effect on the electron beam focal spot size impinging on the target anode. An optimum condition of the parameters was obtained producing good quality of X-ray images. Also, MWCNT yarn was investigated for field emission characteristics and its contribution in the X-ray generation. The dry spinning method was used to fabricate MWCNT yarn from super MWCNTs, which was fabricated by MW-PECVD. The MWCNT yarn has a significant field emission capability in both diode and the triode X-ray generation structure compared to a MWCNT. The low-voltage-field emission of the MWCNT yarn can be attributed to the field enhancing effect of the yarn due to its shape and the contribution of the high-aspect-ratio nanotubes that protrude from the sides of the yarn. Observations of the use of filters on the development of X-ray images were also demonstrated. The amount of exposure time of the samples to the X-ray was also manipulated. The MWCNT yarn can be a good candidate for use in the low voltage field emission application of X-ray imaging.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 가을 학술발표회 논문집
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• pp.275-276
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• 2003

Electrostatic spinning or electrospinning has been recently paid attention to prepare ultrafine fiber mats which are composed of diameters in a range of submicrons to nanoscale size[l]. Due to small diameters and porous structure, electrosun fibers have a high specific surface area and expected to use for broad applications, such as filters, membranes, wound dressing materials, artificial blood vessels. a nonwoven fabric, a reiforcement of nanocomposites[2,3], etc. (omitted)

• 한국잠사곤충학회지
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• 제27권2호
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• pp.54-63
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• 1985

최근 필자가 견직물방추 가공하기 위해 개발한 acryl 합성수지를 합성섬유와 견직물가공된 것이 정전기발생에 어떠한 영향을 미치는가를 알기 위해 실행했다. 본 실험조건은 다음과 같다. (A) 사용가공처리제는 0.5% acryl polymer 525였다(자가제). (B) 각 직물에 대한 정전기 대전압은 K.S. 규격마찰 검사(KS K 0555) 방식에 따라 했다. (C) 마찰대상 직물로서는 K.S. 표준규격 KS K 0905 cotton, nylon, polyester와 공시직물로 했다. (D) 시료로서 silk, nylon, polyester 및 acryl 직물을 상기 합성수지 가공한 것과 안한 것을 구분해서 정전기 대전압을 조사했다. (E) 가공한 것과 가공하지 않은 시료별로 K.S. 표준규격(KS K 0465) 방식에 의해 세탁했다. 이와 같은 조사로 인하여 여러 가지 흥미있는 결과를 얻었는데 그 결과는 다음과 같다. 1. polyster를 제외하고는 silk, bylon, acryl 직물의 가공직물의 대전압이 가공하지 않은 것의 대전압보다 높았다(Table 5참조). 2. 가공한 polyester 직물의 K.S. polyester에 대한 대전압이 현저하게 감소하였다. 3. 견직물의 대전성은 흠이 없는데도 불구하고 높게 나왔는데 그 이유로서는 견직물의 결점이 마찰에 약하다는 성질과 마찰에 의한 K.S. 표준검사규격이 마찰에 강한 합성섬유를 대상으로 되어서 견직물에는 부적합한데 있다. 4. 동질섬유직물간의 마찰로 인한 대전압이 이질섬유직물간이 대전압보다 작게 나왔다. 5. 정전기 대전압은 세탁반복에 따라 증가하였다. 6. 많은 조사 결과가 Contact Electrification Series 원칙에 준하고 있는 사실, 즉 series상 피차 멀리 배치될수록 마찰대전압이 높아지고 있었다(Fig. 6 참조). 7. 이러한 조사 결과는 정전기 발생에 관하는 한 혼방사작업에 문제점으로 될 것이다. 8. 또한 견직물 가공에 임해서도 정전기 대전압이 가공으로 인해 증가할 것이라는 문제를 잊어서는 안 된다.

• 전기화학회지
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• 제5권3호
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• pp.117-124
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• 2002

PAN(polyacrylonitrile)을 DMF(dimethylformamide) 용매에 용해하여 정전방사법에 의해 평균 직경 400 nm의 나노섬유 웹을 제조하였다. 제조된 나노섬유 웹은 산화 안정화, 활성화 공정을 거쳐 활성화 탄소 나노섬유를 제조하여, 전기화학적 특성과 비축전 용량을 측73하였다. 활성화 탄소 나노섬유의 비표면적은 $1230m^2/g-800m^2/g$으로 일반 활성탄소 섬유의 거동과는 다르게 활성화 온도가 증가할수록 감소하는 경향을 나타냈으며, 활성화 에너지 값은 29.2kJ/mol로 활성화 온도에 크게 영향을 받지 않고, 급격한 반응이 일어남을 알 수 있었다. 비축전 용량은 활성화 온도가 $700^{\circ}C,\;750^{\circ}C,\;800^{\circ}C$의 경우 27 F/g, 25 F/g, 22 F/g으로 활성화 온도가 증가할수록 비표면적에 비례하여 낮아지는 경향을 나타냈다.

• Composites Research
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• 제28권5호
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• pp.265-269
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• 2015

최근에 각광을 받고 있는 섬유강화 복합재료, 웨어러블 전자소자, 그리고 전자파 차폐재료 같은 다양한 응용분야에 적용하기 위해서, 높은 기계적 전기적 특성을 갖는 그래핀 섬유를 대량으로 생산하는 일은 산업적으로 매우 의미가 있다. 본 연구에서는 다이-아민 그룹으로 화학적 치환 된 산화 그래핀을 습식 방사 공정을 통하여 섬유로 제조하는 효율적인 공정을 개발하였다. 다이-아민 그룹으로 치환된 산화 그래핀은 합성이 용이하고 수용액에서 분산성이 매우 좋으며, 저렴한 비용으로 대량 생산이 가능한 장점을 가지고 있다. 이렇게 제조된 아민-치환 그래핀 섬유는 산화 그래핀 섬유와 비교해서 높은 기계적, 전기적 특성을 보이기 때문에 웨어러블 전자 소자에 응용이 기대된다.