大学院理学研究院
基本情報
- 所属
- 千葉大学 大学院理学研究院化学研究部門基盤物質化学講座 准教授
- 学位
- 博士(理学)(1998年3月 東京大学)
- 研究者番号
- 40302525
- J-GLOBAL ID
- 202101009352139034
- researchmap会員ID
- R000023017
論文
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Journal of Electron Spectroscopy and Related Phenomena 264 2023年4月 査読有りHard X-ray Photoemission spectra (HAXPES) for Al films on Si substrates were measured, and thickness dependence of the Al and Si core level spectra was obtained. A quantitative analysis of the plasmon-loss processes and the continuous background was performed. Such loss process can be quantitatively understood using a HAXPES analysis, especially for the intensity analysis of the core levels. Si 1 s electrons excite extrinsic Al plasmons and continuous loss features as far as they propagate within the Al film. The results give us important information and enable us to separate the intrinsic, extrinsic and their interference effects in plasmon-loss processes. Even for the high energy excitation inherent to HAXPES, the interference effect between intrinsic and extrinsic plasmon-losses is shown to be not negligible. A stronger contribution from loss features than from the main peaks should be considered for quantitative analysis.
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Physical Chemistry Chemical Physics 2023年 査読有りSolid-solution-type Au–Pt alloy nanoparticles (NPs) were prepared from the nanoclusters of each metal using the polymer-conjugated fusion growth method. The elemental mapping analysis showed that the mixing state of the...
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Journal of the Physical Society of Japan 90(7) 74706-74706 2021年7月15日 査読有りThe excitonic insulator Ta2NiSe5 experiences a first-order structural transition under pressure from rippled to flat layer-structure at Ps ~ 3 GPa, which drives the system from an almost zero-gap semiconductor to a semimetal. The pressure-induced semimetal, with lowering temperature, experiences a transition to another semimetal with a partial-gap of ~0.1-0.2 eV, accompanied with a monoclinic distortion analogous to that occurs at the excitonic transition below Ps. We argue that the partial-gap originates primarily from a symmetry-allowed hybridization of Ta-conduction and Nivalence bands due to the lattice distortion, indicative of the importance of electron-lattice coupling. The transition is suppressed with increasing pressure to Pc ~ 8 GPa. Superconductivity with a maximum Tsc ~ 1.2K emerges around Pc, likely mediated by strongly electron-coupled soft phonons. The electron-lattice coupling is as important ingredient as the excitonic instability in Ta2NiSe5.
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Angewandte Chemie 133(16) 9127-9136 2021年4月12日 査読有り
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Angewandte Chemie International Edition 60(16) 9045-9054 2021年4月12日 査読有り
MISC
5-
Iodine Chemistry and Applications 9781118466292 15-23 2014年11月24日Iodine is one of the essential elements for human nutrition. Iodine measurement in biological samples is carried out almost exclusively by one of two methods: One is a kinetic spectrophotometric method called the Sandell-Kolthoff reaction based on the reduction of yellow Ce(IV) by As(III) to colorless Ce(III), which is normally very slow. Consequently, other methods, for example, inductively coupled plasma mass spectrometry (ICP-MS), are used. This chapter presents the detailed descriptions for these analytical methods. Ion-selective electrodes (ISEs) are commercially available for iodide and have been applied for the determination of iodide. Local structural information such as interatomic distances, coordination numbers, and Debye-Waller parameters, which are complementary to the vibration frequencies obtained by infrared (IR) and Raman spectroscopy, can be obtained by analyzing the extended X-ray absorption fine structure (EXAFS) part of the X-ray absorption spectra.
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Physica Scripta T T115 685-687 2005年 査読有りThe structure of RbBr aqueous solution confined in the interstitial nanospaces of single-wall carbon nanohorn (SWNH) assemblies was elucidated by using extended x-ray absorption fine structure (EXAFS) technique. The decrease of hydration number around a Rb ion is clearly observed. The EXAFS analysis indicates that the highly distorted and dehydrated structure around ions of aqueous solution confined in the nanospace (nanosolution: NSN) to form quasi one-dimensional structure in the interstitial nanospaces of SWNH assemblies. This unique hydration structures formed in nanospaces of SWNH is quite different from that not only of the bulk aqueous solution, but also confined in the slit-shaped nanospaces of activated carbon fiber (ACF). © Physica Scripta 2005.
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NANOTECHNOLOGY IN MESOSTRUCTURED MATERIALS 146 61-64 2003年 査読有りThe hydration structure of RbBr electrolytic solution confined in carbon nanospaces was determined with EXAFS technique and related analyses. The analytical results indicate that the electrolytes confined in hydrophobic nanospaces have an incomplete dehydration structure, because of an intensive restriction and cluster formation of adsorbed water molecules in the nanospaces.
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