• Carbon letters
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• 제15권4호
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• pp.268-276
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• 2014

Recently, methods that usea carbon-based filler, a conductive nanomaterial, have been investigated to develop composite fillers containing dielectric materials. In this study, we added geometric changes to a carbon fiber, a typical carbon-based filler material, by differentiating the orientation angle and the number of plies of the fiber. We also studied the electrical and electromagnetic shield characteristics. Based on the orientation angle of $0^{\circ}$, the orientation angle of the carbon fiber was changed between 0, 15, 30, 45, and $90^{\circ}$, and 2, 4, and 6 plies were stacked for each orientation angle. The maximum effect was found when the orientation angle was $90^{\circ}$, which was perpendicular to the electromagnetic wave flow, as compared to $0^{\circ}$, in which case the electrical resistance was small. Therefore, it is verified that the orientation angle has more of an effect on the electromagnetic interference shield performance than the number of plies.

• 한국기계기술학회지
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• 제13권3호
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• pp.107-111
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• 2011

This carbon nano heating system was consisted of power supply equipment, a carbon fiber and a stainless flexible hose. carbon nano heating system was manufactured by carbon fiber of a power capacity 30kw/h and light-oil hot air heater in control plot was the heating capacity 30,000kcal/h, As the result, Temperature difference due to carbon nano heating system and hot air heater in greenhouse showed that air temperature at experimental greenhouse, comparison greenhouse were $14.8^{\circ}C$, $13.4^{\circ}C$ respectively. It was found that carbon nano heating system and light-oil hot air heater heating cost were 1,095,740won, 2,683,628won. therefore as heating cost saving 60%. Yield of tomatoes cultured in greenhouse using carbon nano heating pipe was 4% inclease. Economic analysis comparison between the carbon nano heating pipe and the hot air heater in greenhouse were 41% respectively.

• 자원환경지질
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• 제42권5호
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• pp.501-507
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• 2009

본 연구에서는 단일 벽(Single-wall) 구조를 갖는 나노크기의 속이 빈(hollow) 볼(Ball)형(NBs; Nano-balls), 짧은 길이 튜브(S-NTs; Short-fiber Nano-tubes)형 및 긴 길이 튜브(L-NTs; Long-fiber Nano-tubes) 물질을 동일한 조성 Al/Ge=1.33을 갖는 Aluminogermanate(ALGE) Precursor 최초 혼합용액의 단순한 pH 조절 과정에서 자기조합(Self-assembly)을 통해 성공적으로 합성하였다. 먼저 pH=13으로의 염기성화(Na/Al=28~30) 및 최종 pH=9 조건에서 5 nm의 균질한 크기를 갖으며, 화학조성인 Al/Ge=1.5~1.6인 속이 빈 구조의 NBs가 합성되었다. pH=13으로의 염기성화 및 최종 pH=4 조건에서는 3.3 nm 지름, 길이 15~20 nm, Al/Ge=2.6~2.8의 S-NTs가 합성되었다. 그러나 pH=9로 염기성화(Na/Al=3.8) 시킨 후 최종 pH=4조건에서는 나노-튜브의 길이가 100 nm 이상인 L-NTs가 처음으로 합성되었다. 이러한 결과는 ALGE Precursor로부터 -Ge-OH 표면에서의 $H^+$-dissociation 정도 차이, 즉, $Na^+$ 양 및 최종 pH 조건을 달리함으로써 의도하는 형태의 ALGE 나노물질 유도가 가능함을 시사한다.

• 한국분말재료학회지
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• 제16권2호
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• pp.131-137
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• 2009

This paper deals with the effects of the surfactant and preplate process (sensitization and activation) on electroless copper plating on carbon nano-fiber (CNF). Ultrasonic irradiation was applied both during dispersion of CNF and during electroless plating containing preplate process. The dispersion of CNF and flatness of the plated copper film were discussed based on the changes in surfactant concentration and preplate process time. It was clearly shown that high concentration of surfactant and long time of preplate process could promote the agglomeration of CNF and uneven copper plating on CNF.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2008년도 춘계학술대회 논문집
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• pp.21-24
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• 2008

Properties of carbon nano fiber (CNF) as field emitters were described. Carbon nano fiber (CNF) of herringbone was prepared by thermal chemical vapor deposition(CVD). Field emitters mixed with organic binders, conductive materials and were prepared by screen-printing process. In order to increase field emissions, the surface treatment of rubbing & peel-off was applied to the printed CNF emitters on cathode electrode. The measurements of field emission properties were carried out by using a diode structure inline vacuum chamber. CNF of herringbone type showed good emission properties that a turn on field was as low as 2.1 $V/{\mu}m$ and current density was as large as 0.15 $mA/cm^2$ of 4.2 $V/{\mu}m$ with electric field. Through the results. we propose that CNFs are suitable for application of electron emitters in Field Emission Devices.

• 센서학회지
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• 제14권5호
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• pp.302-307
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• 2005

Precision displacement of less than a few nm resolution was measured in real-time using fiber optic EFPI sensor. The novel method for real-time processing of analyzing EFPI output signal was developed and verified. Linearity in the mean values of interferometric light intensity among adjacent fringes was shown and verified the sinusoidal approximation algorithm that estimates past and coming fringe values. Real-time signal processing program was developed and the intensity signal of the EFPI sensor was transformed to the phase shift with this program. The resolution below $0.36{\sim}8.6$ nm in the displacement range of $0{\sim}300{\mu}m$ was obtained. The nano-positioner with a piezoelectric actuator and the EFPI sensor system was designed and tested. The positioner successfully reached to the desired destination within 1 nm accuracy.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 추계학술발표대회 논문집
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• pp.3-6
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• 2003

In this work, poly(ethylene oxide) nanofibers were fabricated by electrospinning to prepare nanofibers-reinforced composites. And the PEO powders-impregnated composites were also prepared to compare with physicochemical properties of nanofibers-reinforced composites. Morphology and fiber diameter of PEO nanofibers were determined by SEM observation. Mechanical interfacial properties of the composites were investigated in fracture toughness tests and interlaminar shear strength (ILSS) test. As a result, the fiber diameter decreased in increasing applied voltage. However the optimum condition for the fiber formation was 15 ㎸, resulting from increasing of jet instability at high voltage and the prepared PEO nanofibers were useful in fiber reinforced composites. The PEO-based nanofibers-reinforced composites showed an improvement of fracture toughness factors ($K_{IC} and G_{ IC}$) and ILSS, compared to the composites impregnated with PEO powders. These results were noted that the nanofibers had higher specific surface area and larger aspect ratio than those of the powder, which played an important role in improving the mechanical interfacial properties of the composites.

• Advances in nano research
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• 제5권4호
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• pp.337-357
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• 2017

Knowledge of thin films mechanical properties is strongly associated to the reliability and the performances of Nano Electro Mechanical Systems (NEMS). In the literature, there are several methods for micro materials characterization. Bulge test is an established nondestructive technique for studying the mechanical properties of thin films. This study improve the performances of NEMS by investigating the mechanical behavior of Nano rectangular thin film (NRTF) made of new material embedded in Nano Electro Mechanical Systems (NEMS) by developing the bulge test technique. The NRTF built from adhesively-bonded layers of basalt fiber reinforced polymer (BFRP) laminate composite materials in Nano size at room temperature and were used for plane-strain bulging. The NRTF is first pre-stressed to ensure that is no initial deflection before applied the loads on NRTF and then clamped between two plates. A differential pressure is applying to a deformation of the laminated composite NRTF. This makes the plane-strain bulge test idea for studying the mechanical behavior of laminated composite NRTF in both the elastic and plastic regimes. An exact solution of governing equations for symmetric cross-ply BFRP laminated composite NRTF was established with taking in-to account the effect of the residual strength from pre-stressed loading. The stress-strain relationship of the BFRP laminated composite NRTF was determined by hydraulic bulging test. The NRTF thickness gradation in different points of hemisphere formed in bulge test was analysed.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2007년도 학술발표회 논문집
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• pp.521-522
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• 2007

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2007년도 학술발표회 논문집
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• pp.217-218
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• 2007