• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.158.1-158.1
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• 2011

In this work, we prepared ultramicroporous carbons (UC) prepared by pyrolyzing poly(vinylidene fluoride) with different carbonization temperatures, and investigated the hydrogen storage behaviors. The surface functional groups and specific elements of UC were confirmed by Fourier-transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS), respectively. Textural properties were analyzed using $N_2$ adsorption isotherms at 77 K. The hydrogen storage capacity of the UC samples were investigated by BEL-HP at 298 K/10 MPa. From the results, it was found that the hydrogen storage capacity was enhanced with increasing of specific surface area, resulting from the formation of ultramicropore on the UC.

• Textile Coloration and Finishing
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• v.20 no.5
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• pp.1-6
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• 2008

3-(Hydroxyphenyl phosphinyl) propanoic acid (HPPA) has been one of the most commonly used durable flame retardant agents for polyethylene terephthalate (PET) for many years. We intended to explore the application of HPPA to cellulose fabrics as formaldehyde-free phosphorus based flame retardants (FRs) through green chemistry process. The flame retardancy of the flame-retardant treated cellulose fabrics were characterized by using inductively coupled plasma spectroscopy (ICP) and limiting oxygen index (LOI). Structural changes of the treated cellulose fabrics were carried out by thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR) spectroscopy. To enhance the flame retardancy of HPPA treated cellulose fibers, glycerol polyglycidyl ether (GPE), a crosslinking agent was employed. Both HPPA and GPE treated cotton fabric imparted an LOI value over 26.

• Proceedings of the KAIS Fall Conference
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• 2012.05a
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• pp.431-435
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• 2012

Aluminum containing mesoporous molecular sieves Al-SBA-1 ($n_{Si}/n_{Al}$= 2, 5, 10, 15) was synthesized with a one-step method, and the catalyst was characterized with powder X-ray diffraction (XRD), nitrogen adsorption-desorption, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Finally, we studied the catalytic activities of Al-SBA-1 molecular sieves in Pechmann reaction of 3-methoxyphenol and Ethyl acetoacetate to get 7-methoxy-4-methyl coumarin. Four parameters reaction temperature, time, catalyst weight and reactants ratio were optimized.

• Journal of the Korean institute of surface engineering
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• v.34 no.3
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• pp.258-263
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• 2001

Siloxane thin films were fabricated on a silicon wafer by spin-coating using a siloxane solution made by the sol-gel process. Fluorine was doped using$ CF_4$ plasma treatment. The film was then annealed in-situ state in the nitrogen atmosphere. In order to examine the influence of annealing and fluorine doping on the siloxane thin film, thermogravimetric-differential thermal analysis (TG-DTA), Fourier transform-infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) were used and the dielectric constant was determined by the high-frequency capacitance-voltage method. Stable siloxane films could be obtained by in-situ annealing in a nitrogen atmosphere after $CF_4$ plasma treatment, and the dielectric value of the film was $\varepsilon$ 2.5.

• Journal of Integrative Natural Science
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• v.3 no.3
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• pp.133-137
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• 2010

New synthetic route and characterization of alkyl-capped nanocrystalline silicon (R-n-Si) were achieved from the reaction of silicon tetrachloride with sodium/benzophenone ketal reducing agent followed by n-butyllithium. Surface of silicon nanoparticles was derivatized with butyl group. Effect of oxidation of silicon nanoparticle with benzophenone was investigated for their stabilization. Optical characteristics of silicon nanoparticles were characterized by fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-vis), and photoluminescence (PL) spectroscopy. Butyl-capped silicon nanoparticles exhibited an emission band at 410 nm with excitation wavelength of 360 nm. Average size of n-butyl-capped silicon nanoparticles was obtained by particle size analyzer (PSA) and transmission electron microscopy (TEM). Average size of n-butyl-capped Si nanoparticles was about 6.5 nm.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.49.1-49.1
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• 2011

태양전지 모듈의 25년 이상 보증을 위해 태양전지 모듈을 구성하는 부품 소재의 신뢰성이 부각되고 있다. 현재까지 알려진 태양전지 모듈용 에틸렌 아세테이트 비닐(ethylene Vinyl Acetate, EVA)의 주요 열화 메카니즘은 황변(yellowing)과 박리(delaminaation)이다. 따라서 본 연구에서는 태양전지 모듈을 구성하는 재료 중 EVA 소재의 열화 메커니즘을 도출하기 위해 이미 알려진 스트레스 인자를 이용한 가속 열화시험을 설계한 후 가속열화시험을 실시하였으며, 이로부터 EVA의 열화 메카니즘을 규명하였다. 열화모드 재현을 위해 소형 태양광 모듈을 제작하였으며, Weather-Ometer를 이용하여 열화시험을 수행하였다. 시험조건은 4종 Phase가 1 사이클이 되도록 실험하였으며, Dark 조건 1 Phase 및 Light 조건 3 Phase 조건으로 실시하였다. 태양전지 모듈의 열화량은 매 500 사이클 마다 Light I-V 변화량을 측정하여 분석하였다. EVA의 물리 화학적 열화분석을 위해 단면분석, 적외선분광기(Fourier Transform-Infra Red, FT-IR) 및 주사전자현미경을 이용하여 열화 특성에 대한 분석을 실시하였고, 이를 근거로 EVA의 열화 메커니즘을 규명하였다.

• Bulletin of the Korean Chemical Society
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• v.35 no.3
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• pp.871-874
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• 2014

Monodispersed carbon nanospheres (CNSs) were fabricated by a novel method and their structural properties were investigated. CNSs were prepared by the pyrolysis of nanospherical polystyrenes (PS). With the coating of $SiO_2$ shell, PS particles were effectively separated during pyrolysis process which resulted to CNSs with an average diameter of 40 nm. Moreover, CNSs could be crosslinked with each other through the bondings between the functional groups on their surfaces. Morphology of the fabricated carbon spheres and their crosslinked form were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and fourier transform infrared spectroscopy (FT-IR).

• Journal of the Korean Ceramic Society
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• v.43 no.1 s.284
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• pp.1-3
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• 2006

Well-shaped NaA zeolite cubic crystals of a large size of $5-7{\mu}m$ were synthesized by a hydrothermal method in a mother solution having a $3.55Na_2O:Al_2O_3:1.6SiO_2:593\~2000H_2O$ composition. Thermal treatment of NaA zeolite crystals resulted in the formation of a crystalline phase of $NaAlSiO_4-Camegeite$ between 800 and $900^{\circ}C$. Even at $1000^{\circ}C,\;NaAlSiO_4$ phase was found as a major product. Environmental Scanning Electron Microscopy (ESEM), High Resolution Transmission Electron Microscopy (HRTEM), X-Ray powder Diffraction (XRD), Fourier Transform Infrared (FT-IR) spectroscopy, and DTA/TGA and BET analyses were used to characterize the initial materials and the obtained products after various heat treatments.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.237-240
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• 2002

Amino terminated polyetherimide(ATPEI) has been synthesized by bisphthalic anhydride arid m-phenylenediamine, after that characterized by differential scanning calorimetry(DSC), thermogravimetric analyzer(TGA). Fourier transform (FT-IR) spectroscopy and gel permeation chromatography(GPC). ATPEI was blend to improve the toughness of bisphenol-A type epoxy resin which was cured by nadic methyl anhydride(NMA). The fracture toughness and the molphology of the toughened epoxy resin was evaluated. The toughness of ATPEI modified epoxy resin was higher than that of the PEI modified epoxy resin. In addtion, carbon fiber/ATPEI modified epoxy resin composites were fabricated and the mechanical properties of the resulted composites were investigated.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2009-2012
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• 2014

An anionic surfactant, sodium dodecylbenzene sulfonate (SDBS), was introduced during the ultrasonication process for exfoliation of graphene. The surfactant plays the roles of exfoliator and stabilizer by binding to the graphene surface. The obtained modified graphene was characterized by Fourier-transform infrared spectroscopy (FT-IR) and solid state $^{13}C$ CP/MAS NMR to analyze the binding between molecules, and by X-ray diffraction (XRD) to characterize the bulk structure. The resulting graphene exhibited good dispersion stability in both water and organic solvents.