A5072030877- Quasicrystal Structures and Properties
- Mineralogy and Gemology Studies
- X-ray Diffraction in Crystallography
- Nanocluster Synthesis and Applications
- Fermentation and Sensory Analysis
- Molecular Junctions and Nanostructures
- nanoparticles nucleation surface interactions
- Catalytic Processes in Materials Science
- Surface and Thin Film Phenomena
- Catalytic Cross-Coupling Reactions
- Fungal and yeast genetics research
- Physics of Superconductivity and Magnetism
- Microbial Metabolic Engineering and Bioproduction
- Theoretical and Computational Physics
- Food Quality and Safety Studies
- Nanomaterials for catalytic reactions
- Microstructure and mechanical properties
- Electrocatalysts for Energy Conversion
- Advanced Chemical Physics Studies
- Polyoxometalates: Synthesis and Applications
- Transition Metal Oxide Nanomaterials
- Catalysis and Oxidation Reactions
- Magnetic properties of thin films
- Biofuel production and bioconversion
- Agriculture, Soil, Plant Science
Tokyo University of Science
2020
Yokohama National University
2018
National Institute for Materials Science
2006-2017
Saga University
2012-2016
Zhejiang Sci-Tech University
2014
Yamamoto Hospital
2013
Okayama University of Science
1995-2011
Hacettepe University
2011
Hokkaido University
2008-2010
SPring-8
2010
The Fermi surface of ${\mathrm{Bi}}_{2}$${\mathrm{Sr}}_{2}$${\mathrm{CaCu}}_{2}$${\mathrm{O}}_{8+\mathit{x}}$(001) has been mapped at nearly 6000 points in k space using angle-resolved photoemission 300 K. We observe both features that are good agreement with the local density calculation Massidda, Yu, and Freeman [Physica (Amsterdam) 158C, 251 (1988)] others missing calculation. Among those missing, most importantly, we find a c(2\ifmmode\times\else\texttimes\fi{}2) superstructure on...
We review recent developments in surface studies of single-grain quasicrystals under ultra high-vacuum conditions, focusing on two different topics: structure and growth atomic overlayers surfaces. Quasicrystalline phases are currently used for investigation the first topic icosahedral (i) Al-Pd-Mn, i-Al-Cu-Fe, i-Al-Cu-Ru, i-Ag-In-Yb decagonal (d) Al-Ni-Co, d-Al-Cu-Co. report progress made with all these phases. The second covers study single-element overlayer by vapor deposition.
ConspectusA clear correlation between electronic structure and CO2 selectivity for steam reforming of methanol (SRM) was obtained with PdZn, PtZn, NiZn, PdCd intermetallics on the basis experiments calculations. In order to rule out effects oxide supports, intermetallic powders were simply prepared by alloying in an arc furnace followed crushing a mortar. PdZn exhibit valence densities states similar that Cu significant chemical shifts (larger than 1 eV) Pd 3d respect pure Pd, as verified...
We have found in the SR-HXPS measurement of Piranha-treated Au(111)/mica that gold surface underwent sulfur modification during this treatment, which was believed to only removed impurities from surface. also successfully developed a practical Pd material, SAPd, whose immobilized on sulfur-modified Au. With lowest Pd-releasing levels and high recyclability, is one best materials thus far developed. Because it leaches extremely low into reaction mixtures, removal residual unnecessary using...
We have investigated by scanning tunneling microscopy the growth of Bi and Ag thin films on fivefold surface ${\mathrm{Al}}_{63}{\mathrm{Cu}}_{24}{\mathrm{Fe}}_{13}$ ${\mathrm{Al}}_{72}{\mathrm{Pd}}_{19.5}{\mathrm{Mn}}_{8.5}$ quasicrystal, respectively. For both systems, we observe formation islands with magic height, corresponding to stacking a specific number atomic layers. interpret this unusual morphology in terms quantum size effects, arising from confinement electron within film. The...
The surface electronic structure and CO-oxidation activity of Pt alloys, Pt3T (T = Ti, Hf, Ta, Pt), were investigated. At temperatures below 538 K, the activities increased in order < Pt3Ti Pt3hHf Pt3Ta. center-of-gravity d-band (the center) was theoretically calculated to follow trend Pt3Ta Pt3Hf Pt. showed a volcano-type dependence on center, where exhibited maximum activity. Theoretical calculations demonstrated that adsorption energy CO catalyst monotonically decreases with lowering...
We present XPS studies of semiconducting Nd 2- x Ce CuO 4 (0≦ ≦0.20) and superconducting 1.85 0.15 4- y to clarify the location electron carriers. Examination Ce3 d spectra shows that ions are donors From analysis Cu2 p spectra, Cu + concentration is found increase with . A definite in due reduction procedure for sample. The results suggest conduction carriers takes place square plane this system.
Based on scanning tunneling microscopy of the fivefold surface icosahedral Al-Cu-Fe quasicrystal and refined structure model isostructural i-Al-Pd-Mn, we present evidence that corresponds to bulk truncations at positions where blocks atomic layers are separated by larger interlayer spacings (gaps). Both step-height distribution high resolution images terraces reveal gaps.
We use ultrahigh vacuum scanning tunneling microscopy∕spectroscopy (UHV-STM∕STS) to investigate the electronic properties of single thiolated 12-base-pair poly(GC)-poly(GC) DNA molecules on a Au(111) surface at room temperature. Reproducible current-voltage curves are obtained variable sample-tip separations. The normalized conductance, which can be interpreted as density states, shows well-defined wide band gap. UHV-STM∕STS opens up novel technique probe biomolecules surfaces atomic level.
We present a comprehensive study of Bi thin-film growth on quasicrystal surfaces. The substrates used for the are fivefold surface icosahedral $(i)$-Al-Cu-Fe and $i$-Al-Pd-Mn tenfold decagonal $(d)$-Al-Ni-Co quasicrystals. is investigated at 300 525 K substrate temperatures different coverage $(\ensuremath{\theta})$ ranging from submonolayer to ten monolayers. film characterized by scanning tunneling microscopy, reflection high-energy electron diffraction, x-ray photoelectron spectroscopy....
The surface structural study of an icosahedral $(i)$ quasicrystal the Cd-Yb family is presented. Comparison bias-dependent scanning tunneling microscopy data from fivefold $i\text{-Ag-In-Yb}$ with refined bulk model isostructural $i\text{-Cd-Yb}$ indicates that surfaces are formed at planes intersecting center rhombic triacontahedral clusters, building blocks quasicrystals. These observations open up possibility use this material as a template for epitaxial structures.
Nucleation behaviour of β to ω phase transformations in β-type Ti alloys has been investigated using electron microscopy four cases; (1) along the {112}〈11\\bar1〉 twin boundary, at which compressive stress occurs, (2) by means aging under tensile stressing, (3) on effects amounts quenched-in vacancy specimens from two different temperatures, and (4) due cooling 131 K. Results show that formation nucleation-sites is enhanced both compressive-stress boundary tensile-stress during aging. In a...
We investigate a thin Sn film grown at elevated temperatures on the fivefold surface of an icosahedral $\mathrm{Al}\mathrm{Cu}\mathrm{Fe}$ quasicrystal by scanning tunneling microscopy (STM). At about one monolayer coverage, deposited is found to form smooth height consistent with one-half lattice constant bulk Sn. Analysis based Fourier transform and autocorrelation function derived from high-resolution STM images reveals that grows pseudomorphically hence exhibits quasicrystalline structure.
Abstract Spectroscopic properties of the titled complex are reported compared to other radical bis(phthalocyaninato)lanthanoid(III) complexes. Electronic, infrared, and Ce 3d XPS spectra show that cerium in is neither tri- nor tetravalent 4f electron delocalizes a phthalocyanine π orbital.
Abstract A newly developed, environmentally benign palladium catalyst supported on gallium arsenide, {Pd}‐S‐GaAs(001), has both the lowest recorded leaching and high recyclability for Suzuki–Miyaura coupling. Measurements of surface by synchrotron radiation X‐ray photoelectron spectroscopy show a relationship between activity catalyst. Since {Pd}‐S‐GaAs(001) makes efficient use rare metal Pd, it is useful from an atom‐ economical perspective. Two heterogeneity tests clarify that presence...
The valence band structure of the icosahedral $(i)$ Ag-In-Yb quasicrystal, which is isostructural to binary $i\text{-Cd-Yb}$ system, investigated by ultraviolet photoemission spectroscopy (UPS). Experimental results are compared with electronic-structure calculations a cubic approximant same phase. UPS spectra from fivefold, threefold, and twofold $i\text{-Ag-In-Yb}$ surfaces reveal that near Fermi level dominated $\text{Yb}\text{ }4f$-derived states, in agreement calculations. also exhibit...
We have succeeded in growing an epitaxial film on a quasicrystal. Au-depositions quasiperiodic surface of decagonal Al-Ni-Co quasicrystal gave rise to with tenfold symmetry, i.e., layer multiply twinned ${\mathrm{AuAl}}_{2}$ crystals (110)-oriented surfaces and azimuthal orientations corresponding the symmetry substrate.
We present the first ultrahigh vacuum (UHV) surface study of single-grain icosahedral Ag–In–Yb quasicrystal by using X-ray photoelectron spectroscopy (XPS), reflection high-energy electron diffraction (RHEED), and scanning tunnelling microscopy (STM). This new is found to exhibit surfaces with steps terraces, upon suitable preparation conditions. The Fourier transform high-resolution STM images RHEED patterns reveal that after annealing at appropriate temperatures retains quasicrystalline...