A5074244941- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Electrostatics and Colloid Interactions
- Iron-based superconductors research
- Physics of Superconductivity and Magnetism
- Coagulation and Flocculation Studies
- Advanced Condensed Matter Physics
- Magnetic and transport properties of perovskites and related materials
- Rare-earth and actinide compounds
- Iron oxide chemistry and applications
- Electrowetting and Microfluidic Technologies
- Surfactants and Colloidal Systems
- Semiconductor Quantum Structures and Devices
- Minerals Flotation and Separation Techniques
- Crystallography and molecular interactions
- Microfluidic and Bio-sensing Technologies
- Polymer Surface Interaction Studies
- Pickering emulsions and particle stabilization
- Particle Dynamics in Fluid Flows
- Sodium Intake and Health
- Quantum Dots Synthesis And Properties
- Semiconductor Lasers and Optical Devices
- Transition Metal Oxide Nanomaterials
- Superconductivity in MgB2 and Alloys
- Multiferroics and related materials
University of Tsukuba
2014-2024
Osaka Electro-Communication University
2023
The University of Tokyo
2002-2021
Toyohashi University of Technology
2014-2021
Sapienza University of Rome
2017-2019
Waseda University
2018
Life University
2018
University of Geneva
2017-2018
Tokyo University of Science
2000-2017
Kashiwa Municipal Hospital
2015
We have performed Ce $L_3$-edge x-ray absorption spectroscopy (XAS) measurements on CeO$_{1-x}$F$_x$BiS$_2$, in which the superconductivity of BiS$_2$ layer and ferromagnetism CeO$_{1-x}$F$_x$ are induced by F-doping, order to investigate impact F-doping local electronic lattice structures. The XAS spectrum CeOBiS$_2$ exhibits coexistence $4f^1$ (Ce$^{3+}$) $4f^0$ (Ce$^{4+}$) state transitions revealing mixed valency this system. spectral weight decreases with completely disappears for...
We have studied the effect of RE substitution on structure and local atomic disorder in REO0.5F0.5BiS2 (RE = rare-earth) to understand their correlation with bulk superconductivity these materials. The mean size, affecting chemical pressure, has been varied two series namely Ce1-xNdxO0.5F0.5BiS2 Nd1-ySmyO0.5F0.5BiS2. lattice parameters evolve anomalously, showing an anisotropic shrinkage (elongation) c-axis (a-axis) isotropic expansion increasing size. Bi L3-edge extended X-ray absorption...
Comparing the apparent oxygen utilization (AOU) and CFC tracer ages (τ) between extensive decadal reobservation data along 47°N (’85–’99) 165°E (’87–’00) lines, we found that both AOU τ markedly increased over North Pacific 26.4–27.4 σ θ . The observed increase was almost consistent with calculated from change of τ. Based on a linear trend increasing 30 years (’68–’98) in subpolar region [ Ono et al., 2001], concluded formation rate subsurface water has continuously reduced at least during...
Crackles are discontinuous adventitious sounds, and their separation is an important process in the analysis of lung sounds. In order to separate crackles from vesicular sounds automatically, we used a nonlinear digital filter which was designed nonstationary stationary signals. We applied this recorded six patients with pulmonary fibrosis. The satisfactory enough make method useful clinical medicine.
We have used Bi and Ce L3-edges extended x-ray absorption fine structure measurements to study local of CeO1−xFxBiS2 system as a function F-substitution. The both BiS2 active layer CeO1−xFx spacer changes systematically. in-plane Bi–S1 distance decreases (ΔRmax ∼ 0.08 Å) the out-of-plane Bi–S2 increases 0.12 with increasing F-content. On other hand, Ce-O/F 0.2 concomitant decrease Ce–S2 0.15 Å). Interestingly, is characterized by large disorder that results provide useful information on...
We have investigated the electronic structure of ${\mathrm{BiS}}_{2}$-based ${\mathrm{CeO}}_{0.5}{\mathrm{F}}_{0.5}{\mathrm{BiS}}_{2}$ superconductor using polarization-dependent angle-resolved photoemission spectroscopy (ARPES), and succeeded in elucidating orbital characters on Fermi surfaces. In rectangular pockets around $X$ point, straight portion parallel to ${k}_{y}$ direction is dominated by Bi $6{p}_{x}$ character. The polarization indicates underlying quasi-one-dimensional...
Time-resolved dynamic light scattering is used to measure absolute heteroaggregation rate coefficients and the corresponding stability ratios for between amidine sulfate latex particles. These measurements are complemented by respective quantities homoaggregation of two systems electrophoresis. Based on latter measurements, calculated using Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. In monovalent salt solutions, types particles investigated oppositely charged. presence multivalent ions,...
The relation between the arteriolar diameters and hypertensive glomerulosclerosis was studied by using microvascular casts histological evaluation. Spontaneously rats 4 weeks of age were divided into three groups: nontreated, captopril (40 mg/kg/day)-treated, trichlormethiazide (1 mg/kg/day) with hydralazine (20 mg/kg/day)-treated. Wistar-Kyoto served as controls. At 6 old, captopril-treated showed a lower blood pressure larger afferent diameter compared control rats. 20 nontreated group...
We examine the mechanism responsible for optical activity of a two-dimensional array gold nanostructures with no mirror symmetry on dielectric substrate. Measurements different incident angles, polarizations and sample orientations allow us to reveal that observed polarization effect is enhanced by surface plasmon resonance. By performing numerical simulation rigorous diffraction theory we also show grating chirality can be described in terms non-coplanarity electric field vectors at front...
Using near-field optical microscopy, we have performed coherent excitation spectroscopy of self-assembled quantum dots (SAQDs). A pair pulses with a time delay between them allows measurement the temporal coherence carrier wave function in single dots. The observed decoherence is about 15 ps and well explained by resonant Raman scattering phonons. Furthermore, beats originating from superposition two closely spaced states been observed. This opens up possibilities mechanical control SAQDs.
An understanding of nanobubble (NB) migration in porous media is needed for potential environmental applications. The solution chemistry well known to be a critical factor determining interactions other colloids and nanoparticles with surfaces. However, little quantitative research has examined the influence on NB transport. One-dimensional column experiments were therefore conducted investigate transport, retention, release NBs glass beads under different conditions. concentrations effluent...
We report an angle-resolved photoemission spectroscopy (ARPES) study on a triangular lattice superconductor Ir$_{1-x}$Pt$_{x}$Te$_2$ in which the Ir-Ir or Te-Te bond formation, band Jahn-Teller effect, and spin-orbit interaction are cooperating competing with one another. The Fermi surfaces of substituted system qualitatively similar to structure calculations for undistorted IrTe$_2$ upward chemical potential shift due electron doping. A combination ARPES indicates that Te $5p$ removes...
We have performed Ce $L_3$-edge x-ray absorption spectroscopy (XAS) and $4d$-$4f$ resonant photoemission (PES) on single crystals of CeO$_{1-x}$F$_x$BiS$_2$ for $x=0.0$ 0.5 in order to investigate the $4f$ electronic states. In XAS, mixed valence was found sample F-doping suppresses it, which is consistent with results polycrystalline samples. As PES, we that electrons both $0.5$ systems respectively form a flat band at 1.0 eV 1.4 below Fermi level there no contribution surfaces....
Recently CeOBiS2 system without any fluorine doping is found to show superconductivity posing question on its origin. Using space resolved ARPES we have a metallic phase embedded in the morphological defects and at sample edges of stoichiometric CeOBiS2. While bulk semiconducting, characterized by usual electron pocket X point, similar Fermi surface doped BiS2-based superconductors. Typical size observed domain larger than superconducting correlation length suggesting that undoped might be...