• Bulletin of the Korean Chemical Society
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• 제28권12호
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• pp.2481-2485
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• 2007

Spatially resolved, quantitative, non-destructive analysis using synchrotron x-ray reflectivity (XR) with subnano-scale resolution was successfully performed on the nanoporous organosilicate thin films for low dielectric applications. The structural information of porous thin films, which were prepared with polymethylsilsesquioxane and thermally labile 4-armed, star-shaped poly(ε-caprolactone) (PCL) composites, were characterized in terms of the laterally averaged electron density profile along with a film thickness as well as a total thickness. The thermal process used in this work caused to efficiently undergo sacrificial thermal degradation, generating closed nanopores in the film. The resultant nanoporous films became homogeneous, well-defined structure with a thin skin layer and low surface roughness. The average electron density of the calcined film reduced with increase of the initial porogen loading, and finally leaded to corresponding porosity ranged from 0 to 22.8% over the porogen loading range of 0-30 wt%. In addition to XR analysis, the surface and the inner structures of films are investigated and discussed with atomic force and scanning electron microscopy images.

• 한국응용과학기술학회지
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• 제25권3호
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• pp.380-387
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• 2008

The effects of the applied stretch and MgADP binding on the structure of the actin and myosin cross-bridges in rabbit fibers in the rigor state have been investigatedwith improved resolution by x-ray diffraction using synchrotron radiation. To clarify the structure of the ATP hydrolysis intermediates formed by actin and myosin cross-bridges,the effects of various phosphate analogs in the of MgADP on the structure of the thin and thick filaments in glycerinated rabbit muscle fibers in the rigor state investigated by x-ray diffraction with a short exposure time using synchrotron radiation. These results strongly suggest that when MgADP and phosphate analogs such as metallofluorides(BeF3 and AlF4)and vanadate(VO4(Vi)) were added the rigor fibers in the presence of the ATP-depletion backup system, the intensities of the actin-based layer lines were markedly weakened. We found that the intensity of the 14.5 nm-based meridional reflections increase by 20-50% when phosphate analogs such as metallofluorides(BeF3 and AlF4) and vanadate(VO4(Vi)) was added to the rigor muscle.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.171-171
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• 2011

Co and Fe doped multi-wall carbon nano-tubes (MWCNTs) synthesized by microwave plasma enhanced chemical vapor deposition (PECVD) technique are investigated with synchrotron radiations at Pohang Light Source (PAL) and European Synchrotron Radiation Facility (ESRF). Near edge x-ray absorption spectroscopy (NEXAFS) measurement at C K, Co $L_{3,2}$ and Fe $L_{3,2}$-edges, and x-ray magnetic circular dichroism (XMCD) at Co and Fe $L_{3,2}$-edges have been carried at 7B1 XAS KIST and 2A MS beamline, respectively, to understand the electronic structure and responsible magnetic interactions at room temperature. X-ray absorption spectroscopy (XAS) at C K-edge shows significant p-bonding and Co and Fe L-edges proves the presence of $Co^{2+}$ and $Fe^{2+}$ in octahedral symmetry. Co and Fe doped MWCNTs show good XMCD spectra at 300K. The effect on the magnetism is also studied through swift heavy ion (SHI) radiations and magnetism is found enhanced and change in the electronic structure in Co-CNTs is investigated.

• 한국콘텐츠학회논문지
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• 제16권12호
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• pp.70-77
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• 2016

본 연구에서는 거머리의 미세한 해부구조를 3차원적으로 분석 가능한 방사광의 경 엑스선 이미징을 통하여 객관적 분석법 및 생체모사기술 구축을 위한 기초자료를 구축하고자 하였다. 우리는 방사광을 이용하여 거머리의 미세 구조영상을 얻을 수 있었고, 3차원적인 해부학적 분석이 가능함을 확인하였다. 또한 방사광을 통해 얻은 데이터는 내부구조의 미세조직까지 관찰 가능하기 때문에 성분 분석 및 생리적, 기능적 측면으로도 연구의 토대가 될 것으로 사료된다. 더 나아가 추후 거머리로부터 생체모사기술 연구 분야 등에 기여할 수 있을 것이라 기대된다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1998년도 제16회 학술발표회 논문개요집
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• pp.161-161
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• 1998

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1997년도 춘계학술발표회 논문집
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• pp.190-192
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• 1997

• 한국재료학회:학술대회논문집
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• 한국재료학회 2006년도 춘계학술발표대회 및 제10회 신소재 심포지엄 논문개요집
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• pp.8.1-8.1
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• 2006

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2019년도 춘계학술논문요약집
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• pp.149-150
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• 2019

• 한국고분자학회지:고분자과학과기술
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• 제8권1호
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• pp.57-66
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• 1997

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.2095-2097
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• 2000

Applications of soft X-ray which corresponds to the wavelength of the order of 1 nm and to the photon energy of the order of 1 key respectively, requires intense sources. Only synchrotron sources were available recently. The development of a new laboratory-sized source of soft X-ray radiation is required for wide applications. This paper introduces the generation of soft X-ray using laser-induced plasma.