Tokyo University of Science

About: Tokyo University of Science is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Catalysis & Thin film. The organization has 15800 authors who have published 24147 publications receiving 438081 citations. The organization is also known as: Tōkyō Rika Daigaku & Science University of Tokyo.

Anisotropic power-law inflation

Abstract: We study an inflationary scenario in supergravity model with a gauge kinetic function. We find exact anisotropic power-law inflationary solutions when both the potential function for an inflaton and the gauge kinetic function are exponential type. The dynamical system analysis tells us that the anisotropic power-law inflation is an attractor for a large parameter region.

Universal features of quantized thermal conductance of carbon nanotubes.

Abstract: The universal features of quantized thermal conductance of carbon nanotubes (CNTs) are revealed through a theoretical analysis based on the Landauer theory of heat transport. The phonon-derived thermal conductance of semiconducting CNTs exhibits a universal quantization in the low-temperature limit, independent of the radius or atomic geometry. The temperature dependence follows a single curve given in terms of temperature scaled by the phonon energy gap. The thermal conductance of metallic CNTs has an additional contribution from electronic states, which also exhibits quantized behavior up to room temperature.

Synthesis of hard carbon from argan shells for Na-ion batteries

Abstract: Hard carbon is an attractive material for negative electrodes in sodium-ion batteries. Herein, we report a new hard carbon synthesized via carbonization of argan shell biomass, which delivers an enhanced capacity higher than 330 mA h g−1 based upon reversible sodium insertion. We prepared hard carbon under different high-temperature treatment and biomass pretreatment conditions. The graphitization degree of the hard carbon increased as the carbonization temperature increased; simultaneously, the reversible capacity for sodium storage was significantly influenced by the carbonization temperature. Structural characterization revealed differences in the structures of the hard carbons synthesized at different carbonization temperatures, which elucidates the correlation between the increased capacity and the micropore size available for sodium storage. The composite electrodes containing the argan hard carbons with a sodium polyacrylate binder were tested in non-aqueous sodium half cells. The electrodes delivered reversible capacities as high as 300 mA h g−1 at a current density of 25 mA g−1 with superior reversibility and capacity retention of 94.1% after 70 cycles. By carbonization of argan shell biomass treated with HCl aqueous solution, we successfully demonstrated a higher reversible capacity of 333 mA h g−1 and an excellent capacity retention of 96.0% after 100 cycles.

Highly efficient decomposition of pure water into H2 and O2 over NaTaO3 photocatalysts

Abstract: NaTaO3 with 4.0 eV band gap showed a high activity for the decomposition of pure water into H2 and O2 without co-catalysts when it was prepared in the presence of excess Na in order to prevent the formation of defects by the volatilization of Na. When NiO was supported on the NaTaO3 powder, the activity was drastically increased. The quantum yield of the NiO(0.05 wt%)/NaTaO3 photocatalyst was 28% for the water splitting at 270 nm.