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: Thin film & Enantioselective synthesis. 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.

Point nodes persisting far beyond Tc in Bi2212

Abstract: In contrast to a complex feature of antinodal state, suffering from competing orders, the pairing gap of cuprates is obtained in the nodal region, which therefore holds the key to the superconducting mechanism. One of the biggest question is whether the point nodal state as a hallmark of d-wave pairing collapses at Tc like the BCS-type superconductors, or it instead survives above Tc turning into the preformed pair state. A difficulty in this issue comes from the small magnitude of the nodal gap, which has been preventing experimentalists from solving it. Here we use a laser ARPES capable of ultrahigh-energy resolution, and detect the point nodes surviving far beyond Tc in Bi2212. By tracking the temperature evolution of spectra, we reveal that the superconductivity occurs when the pair-breaking rate is suppressed smaller than the single-particle scattering rate on cooling, which governs the value of Tc in cuprates.

Antioxidant action by gold-PAMAM dendrimer nanocomposites.

Abstract: Gold−dendrimer nanocomposites were prepared in the presence of poly(amidoamine) (PAMAM) dendrimer (generation 3, 3.5, 5, and 5.5) via reduction of HAuCl4 with sodium borohydride. The average particle size of the gold nanoparticles was independent of the dendrimer concentration, ranging between 3.0 and 4.3 nm in diameter. The catalytic activities of the gold−dendrimer nanocomposites upon elimination of hydroxyl radicals formed in an H2O2/FeSO4 system were examined using a spin-trapping method. The gold−dendrimer nanocomposites exhibited high catalytic activities which were hardly affected by the concentration and the generation of the dendrimer except PAMAM dendrimer 3.5. The highest activity for the gold−PAMAM dendrimer 3.5 nanocomposites was 85 times that of ascorbic acid.

Polyacrylate Modifier for Graphite Anode of Lithium-Ion Batteries

Abstract: Polyacrylates were applied as a binder of graphite electrode in a lithium-ion cell to modify the interface. Compared to a conventional binder, poly(vinylidene fluoride), the efficiency at the initial cycle was improved by poly(acrylic acid) and alkali polyacrylates in an ethylene carbonate (EC)-based electrolyte with highly reversible lithium intercalation. In a LiClO 4 propylene carbonate (PC) solution, the poly(vinylidene fluoride) electrode showed a huge irreversible capacity as is generally known. However, the polyacrylate-modified graphite demonstrated highly reversible lithium intercalation in the PC electrolyte containing no film-forming additives as well as in the EC electrolyte due to the interfacial modification with polyacrylates.

Thermoelectric Characteristics of a Commercialized Mg2Si Source Doped with Al, Bi, Ag, and Cu

Abstract: The thermoelectric characteristics of commercial polycrystalline Mg2Si doped with Bi, Al + Bi, Ag, and Cu were examined. The samples for the thermoelectric measurements were prepared using the plasma-activated sintering (PAS) technique. The measured values of the Seebeck coefficient were compared with values calculated using the all-electron band-structure calculation package (ABCAP) based on a full-potential augmented-plane-wave (FLAPW) band-structure calculation in a local density approximation (LDA). For the Bi + Al-co-doped samples, the observed values of the dimensionless figure of merit, ZT, were higher than those of solely Bi-doped samples. The maximum value obtained for Bi + Al-doped Mg2Si was 0.77 at 862 K. For the Ag-doped samples, ZT was significantly lower than that of the Bi + Al-doped samples, with the maximum value being about 0.11 at 873 K.