Noriyuki Isobe

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Nitroxy radical catalyzed oxidation with hypochlorite/bromide (TEMPO-mediated oxidation) was performed on a cellulose hydrogel prepared using LiOH/urea solvent. TEMPO oxidation successfully introduced carboxyl groups onto the surface of the cellulose hydrogel with retention of the gel structure and its nanoporous property. The equilibrium measurement of(More)
Pulverized samples of wood, cedar and eucalyptus were treated with 5 N NaOH solutions at 25–150 °C. Hemicellulose and lignin content in the samples decreased with increasing treatment temperatures, while the recovery of glucose was maintained at nearly 90 %. X-ray diffraction analysis showed that the content of the original cellulose I structure in the(More)
Molecular process of regeneration-gelation of cellulose from aqueous alkali-urea solvent was monitored by synchrotron-radiation X-ray. The wide-angle diffraction from cellulose during regeneration, both by coagulant and heating, gave information on behavior of cellulose molecules, i.e. the glucopyranoside rings first stack by hydrophobic interaction to form(More)
An 80 ksec Chandra ACIS observation of the radio galaxy 3C 452 is reported. A diffuse X-ray emission associated with the lobes has been detected with high statistical significance, together with the X-ray nucleus of the host galaxy. The 0.5–5 keV ACIS spectrum of the diffuse emission is described by a twocomponent model, consisting of a soft thermal plasma(More)
Cellulose gels regenerated from aqueous alkali-urea solvent were found to have different surface polarity depending on coagulant species. Gels coagulated by alcohols adsorbed Congo red about twice as much as those coagulated by aqueous coagulants. The difference was also noted in the iodine reaction; the alcohol-coagulated gels showed blue coloration(More)
The binary X-ray pulsar A0535+262 was observed with the Suzaku X-ray observatory, on 2005 September 14 for a net exposure of 22 ksec. The source was in a declining phase of a minor outburst, exhibiting 3–50 keV luminosity of ∼ 3.7 × 10 ergs s at an assumed distance of 2 kpc. In spite of the very low source intensity (about 30 mCrab at 20 keV), its electron(More)
A follow-up X-ray study was made of the west lobe of the radio galaxy Fornax A, (NGC 1316) based on new ASCA observations made in 1997 for 98 ks, and incorporating the previous observation in 1994 for 39 ks. The 0.7–10 keV spectrum of the emission can be described by a power-law of energy index 0.74 ± 0.10, which agrees with the synchrotron radio index of(More)
Pullulan is soluble in both N,N-dimethylacetamide (DMAc) and LiCl/DMAc. Here, the solution-state structures of pullulan in these two solvents were studied by size-exclusion chromatography with multi-angle laser light scattering (SEC/MALLS) and nuclear magnetic resonance (NMR) analyses. SEC/MALLS and off-line refractive index analyses revealed that the(More)
Suzaku observations are reported of the BL Lacertae object OJ 287, performed on 2007 April 10– 13 during the optical quiescent phase and on 2007 November 7–9 during the optical flaring phase. We organized the simultaneous the radio and optical observations with the Nobeyama Millimeter Array and optical KANATA telescope at Hiroshima University, respectively.(More)
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