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Shinji Matsui

Publications and source records attributed to Shinji Matsui.

2 recordsLinked to original sources

Novel DNA nano-patterning design method utilizing poly-L-lysine patterning by nanoimprint lithography.

The DNA properties have been deliberated to comprehend new functional bio-devices. However there are few reports on DNA nano-patterning to make them. Therefore, we have tried DNA nano-patterning by using a nanoimprint process. A substrate coated with a poly-L-lysine was heated at 120 degrees C for 5 min in atmosphere, and nanoimprint carried out at 120 degrees C, 6 MPa, 5 min, and we applied 1 mg/ml DNA solution on the substrate and immobilized with the poly-L-lysine. Finally the substrate was washed at twice in water and at once in hot water intensely. DNA lines that consist of lines at about 700 nm as line width was obtain, and the very fine lines correspond to convex patterns of the mold surface. These results suggest that the imprint would make the poly-L-lysine reform by exposing it under high pressure and high temperature. Therefore since DNA is immobilized with the amino group in the poly-L-lysine, a lot of amino group would expose on the surface by the imprint from the balk, and would be patterned DNA.

Adsorption↗

Excitation energy dependence for the Li 1s X-ray photoelectron spectra of LiMn2O4.

The Li 1s XPS (X-ray Photoelectron Spectroscopy) spectra of LiMn2O4, which is one of the major positive-electrode materials in lithium-ion rechargeable batteries, and MnO2 as a reference material, were measured by a laboratory-type XPS spectrometer. The Li 1s peak was not observed in the spectra excited by the Mg Kalpha line (1253.6 eV), because the Li 1s peak overlapped the background of the Mn 3p peak of LiMn2O4. The photoionization cross section of Mn 3p was larger than that of Li 1s for Mg Kalpha excitation. Therefore, the XPS measurement of LiMn2O4 by soft X-ray synchrotron excitation was carried out at beamline BL-7B on NewSUBARU synchrotron facility. Excitation energies of 110, 120, 130, 140, 150 and 151.4 eV were selected. The Li 1s peak was clearly observed in these XPS spectra. In order to investigate the excitation energy dependence, the area ratio of the Li 1s and Mn 3p peaks in the XPS spectra was plotted against the excitation energy. As a result, when the excitation energy was 110 eV, the area ratio had the maximum value.

Journal Article↗