• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.292-292
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• 2010

Bimodal Tram is driven by both engine and Lithium Polymer battery pack which consists with 168 cells of LPB(80Ah, 650Vdc). LPB pack is very frequently charged and discharged in driving. Temperature inside of LPB pack makes an great effect on both charging and discharging capacity which seem to be related with LPB internal resistance. LPB internal resistance is increasing or little decreasing with the decreased temperature under 10 - $20^{\circ}C$ and the increased temperature over $30^{\circ}C$ which is similar to the temperature characteristics of single LPB cell. This paper has analyzed the driving characteristics of LPB pack for bimodal tram is running with either battery mode or hybrid mode.

• Macromolecular Research
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• 제17권9호
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• pp.697-702
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• 2009

Mesoporous ethanesilica thin film was prepared using PEO-PLGA-PEO triblock copolymers as structure-directing agents and (1,2-bis(triethoxysilyl) ethane BTESE; bridged organosilicates) as inorganic precursors via one-step sol-gel condensation of ethanesilica precursors. The mesostructure of ethanesilica films is critically dependent on the processing experimental parameters after the hydrolyzed silica sol mixture was spin-cast. This study examined the effects of the block copolymer template/organosilica precursor ratio in the casting solution and aging period before calcination of the mesostructure. It was further demonstrated that mesoscopic ordering of organosilicate thin films is induced by the rearrangement of block copolymer template/organosilica hybrid during thermal decomposition of the PEO-PLGA-PEO triblock copolymer. The mesoporous structure and morphology were characterized by SAXS, TEM and solid-state NMR measurement.

• Journal of the Optical Society of Korea
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• 제12권3호
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• pp.157-161
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• 2008

A wavelength-selective reflector, composed of a double-ring-resonator add/drop filter and a loop-back mirror at the drop port to be used for a hybrid-integrated tunable laser is designed and fabricated. High-index-contrast polymer waveguide is used to realize a compact device as small as $2mm{\times}0.4mm$. The radii of the rings are slightly different from each other to obtain a wide wavelength tuning via a vernier effect. Peak reflectivity is measured to be 52% for TE mode and polarization-dependent wavelength shift is 0.95 nm. The tuning range is measured to be about 42 nm for applied current as small as 46 mA.

• Fibers and Polymers
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• 제4권3호
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• pp.97-101
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• 2003

Polymer/silicate nanocomposites were prepared via two-step manufacturing process: a master batch preparation and then mixing with matrix polymer. A hybrid of PMMA and Na-MMT with exfoliated structure was first prepared by emulsion polymerization of MMA in the presence of Na-MMT. For the case that SAN24, miscible with PMMA, is used as matrix, we could prepare a nanocomposite with exfoliated structure. However, SAN31 nanocomposite shows the aggregation and/or reordering of the silicate layers due to the immiscibility between SAN31 and PMMA.

• 한국고분자학회지:고분자과학과기술
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• 제19권6호
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• pp.474-489
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• 2008

• 반도체디스플레이기술학회지
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• 제16권4호
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• pp.1-4
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• 2017

Encapsulation of organic based devices is essential issue due to easy deterioration of organic material by water vapor. Atomic layer deposition (ALD) is a promising solution because of its low temperature deposition and quality of the deposited film. Moisture permeation has a mechanism to pass through defects, Thin Film Encapsulation using inorganic / organic / inorganic hybrid film has been used as promising technology. $Al_2O_3$ / Polymer / $Al_2O_3$ multilayer film has shown excellent environmental protection characteristics despite of thin thicknesses of the films.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.1-11
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• 2018

Polymer composites offered broad engineered applications, however their diversity get restricted owing to fluctuations in thermomechanical properties during heating or cooling hence great concern required prior their applications through thermomechanical analysis (TMA). Traditionally, TMA or dilatometry found to be simple, ideal, reliable, sensitive, excellent and basic thermal analytical technique. TMA provides valuable information on thermal expansion, glass transitions temperature (Tg), softening points, composition and phase changes on material of having different geometries simply by applying a constant force as a function of temperature. This compilation highlights the basics and experimental of TMA for both research and technical applications and also provide literature on TMA of polymers, hybrid composites, nanocomposites and their diverse applications.

• Transactions on Electrical and Electronic Materials
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• 제17권3호
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• pp.163-167
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• 2016

Inverter surge resistant enameled wire was prepared with an organic/inorganic hybrid nanocomposite, and the effect of ambient temperature on the insulation lifetime of the enameled wire in the form of twisted pair was studied by a withstanding voltage tester. The organic polymer was Polyesterimide-polyamideimide (EI/AI) and the inorganic material was a Nano-sized silica (average particle size : 15 nm). The enamel thickness was 50 μm and the ambient temperature was 100, 150, 200, and 250, respectively. Transmission electron microscopy (TEM) observation showed that Nano-sized Silica were evenly dispersed in EI/AI. There were many air gaps in a twisted pair, therefore, when voltage was applied to the twisted pair, enamel erosion took place in the air gap area because of partial discharge accordi, ng to Paschen’s law. As ambient temperature increased, insulation lifetime decreased according to Arrhenius relationship, which was explained by the increasing mobility of polymer chains in EI or AI. And insulation breakdown voltage value at 10 kHz was 1,864.5 sec (31.1 min), which is 1.9 times higher than at 20 kHz, 981.6 sec (16.4 min).

• 에너지공학
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• 제11권3호
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• pp.254-261
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• 2002

The fabrication method for the main components of the polymer electrolyte membrane fuel cell stack such as electrodes, membrane-electrode assemblies, and bipolar plates was established for the effective electrode area of 240 ㎠. A counter-flow type 100-cell stack was fabricated by using the above components and then a maximum power of 7.44 kW for H$_2$/O$_2$ and 5.56 kW for H$_2$/air could be obtained at 70$\^{C}$ and 1 atm. It was seen that the distribution of the OCV for unit cells in the stack was uniform but the voltage deviation increased as the load increased due to the IR drop and the electrode polarization. The stack was applied to the power source of the fuel cell/battery hybrid electric golf car. It produced about 1 kW at a room temperature operation during the test run, which occupied about 43% of the total power required by the 2.3 kW motor.

• 폴리머
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• 제24권2호
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• pp.174-181
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• 2000

방사선 전조사법을 이용하여 아크릴로니트릴을 ACF/PP 복합섬유에 그라프트 반응시켜 섬유형 ACF/PP-g-AN 공중합체를 합성하였다. 합성한 공중합체의 FT-lR 결과 2250$cm^{-1}$ / 부근에서 -C=N에 대한 피크, 3450$cm^{-1}$ / 부근에서 -OH와 -NH$_2$에 의한 피크 확인으로 그라프트 반응 및 아미드옥심화 반응을 확인할 수 있었다. 아미드옥심화된 ACF/PP-g-AN 공중합체의 우라늄 이온에 대한 흡착능의 최적시간은 8일이었으며, 최적 pH는 8이었다. 동일 조건하에서의 흡착능은 아미드옥심기의 함량이 증가할수록, 그라프트율이 116.3%일 때 최대 흡착능을 나타내었다. 또한 ACF/PP-g-AN 공중합체는 10회 이상 흡착능의 변화없이 흡탈착이 가능한 홉착제임을 알 수 있었다.