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901.
Hiroshi Abe Yusuke Imai Takefumi Goto Yukihiro Yoshimura Masami Aono Takahiro Takekiyo Hitoshi Matsumoto Takashi Arai 《Metallurgical and Materials Transactions A》2010,41(5):1137-1143
Crystal structures of room-temperature ionic liquid (RTIL)-H2O mixtures are determined by the X-ray diffraction method. The RTIL is N,N-diethyl-N-methyl-N-2-methoxyethyl ammonium tetrafluoroborate, [DEME][BF4]. At 0.9 mol pct H2O, two kinds of superstructures occur simultaneously without a strain. Also, the volume of the unit cell is very small only
at 0.9 mol pct additives. This relates to the composite domain structure, including a twin-related one, as an elastic anomaly.
At other water concentrations, such an extraordinary behavior is not observable. By assuming a sublattice having an equivalent
lattice constant, a water network at 1 mol pct H2O is simulated using a Monte Carlo (MC) method. The network develops over the medium range in the simulation box. 相似文献
902.
Nobuyuki Miyahara Toshihiro Honma Takashi Fujisawa 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(1):57-61
The effects of irradiation of a Nd-Fe-B permanent magnet by fast neutrons was investigated. The decrease in measured magnetic flux density at the center of the magnets were 0.6%, 6.9%, 25.2% and 47.3% after continuous irradiation of 1.1 kGy, 3.7 kGy, 5.6 kGy and 7.4 kGy, respectively. On the other hand, the decrease due to non-continuous irradiation, in which the magnet was first irradiated at 3.7 kGy, then irradiated again at 3.7 kGy nine months later, was 14% smaller than that of continuous irradiation, even for the same total dose. The temperature coefficient of the magnetization did not change with irradiation. Some radioactive materials, such as 147Nd, 151Pm, and 54Mn, were detected in the magnet after irradiation. 相似文献
903.
Xinnan ZHANG Takashi IZATO Junzo MUNENOTO Daisuke MATSUSHITA Tetsu YOSHIDA 《Frontiers of Structural and Civil Engineering》2010,4(4):438-449
This paper investigates the staying and moving characteristics of office workers in a non-territorial office using an ultra wide band (UWB) impulse radio sensor network. The differences between office workers’ staying and moving are clarified according to the individual workstation type that they select. The study determines the characteristics of each type of workstation. By clarifying office workers’ preference for staying and moving with regard to individual workstation types and office worker post, the reasons why office workers in different posts tended to select different types of workstations were revealed. Specifically, leaders tended to select workstations at the “inner meeting corner side” most frequently, as they had a greater need to stay in other areas. In contrast, ordinary staff needed to visit office workers in other areas less often, and as such, they tended to select individual workstations at the “middle meeting corner side.” Barring this, they tended to select individual workstations at the “middle corridor side” or “outer-meeting corner side.” Temporary staff members had little need to visit or stay at other places so they tended to select individual workstations at the “window side,” which is seldom visited or stayed at by other office workers and they could be disturbed less often from their solo work. 相似文献
904.
Chuangchote S Fujita M Sagawa T Sakaguchi H Yoshikawa S 《ACS applied materials & interfaces》2010,2(11):2995-2997
We propose new strategy to facilitate the fabrication of conjugated polymer fiber with higher oriented structures, which focused on electrospinning of a blend solution of regioregular poly(3-hexylthiophene) (rr-P3HT) and poly(vinyl pyrrolidone) (PVP). SEM observation revealed that the blend system forms homogeneous composite nanofibers. This system exhibits the specific feature of strong interchain contribution of P3HT from UV-vis absorption, fluorescence spectroscopic, XRD, and photoelectron spectrometric (for HOMO levels) investigations. We also demonstrate the removal of the PVP component from the P3HT/PVP composite fibers through the selective extraction and such strong interchain stacking of pristine P3HT fiber mat can be remarkably maintained. 相似文献
905.
New glyme-cyclic imide lithium salt complexes as thermally stable electrolytes for lithium batteries
Takashi Tamura 《Journal of power sources》2010,195(18):6095-12191
New glyme-Li salt complexes were prepared by mixing equimolar amounts of a novel cyclic imide lithium salt LiN(C2F4S2O4) (LiCTFSI) and a glyme (triglyme (G3) or tetraglyme (G4)). The glyme-Li salt complexes, [Li(G3)][CTFSI] and [Li(G4)][CTFSI], are solid and liquid, respectively, at room temperature. The thermal stability of [Li(G4)][CTFSI] is much higher than that of pure G4, and the vapor pressure of [Li(G4)][CTFSI] is negligible at temperatures lower than 100 °C. Although the viscosity of [Li(G4)][CTFSI] is high (132.0 mPa s at 30 °C), because of its high molar concentration (ca. 3 mol dm−3), its ionic conductivity at 30 °C is relatively high, i.e., 0.8 mS cm−1, which is slightly lower than that of a conventional organic electrolyte solution (1 mol dm−3 LiTFSI dissolved in propylene carbonate). The self-diffusion coefficients of a Li+ cation, a CTFSI− anion, and a glyme molecule were measured by the pulsed gradient spin-echo NMR method (PGSE-NMR). The ionicity (dissociativity) of [Li(G4)][CTFSI] at 30 °C is ca. 0.5, as estimated from the PGSE-NMR diffusivity measurements and the ionic conductivity measurements. Results of linear sweep voltammetry revealed that [Li(G4)][CTFSI] is electrochemically stable in an electrode potential range of 0-4.5 V vs. Li/Li+. The reversible deposition-stripping behavior of lithium was observed by cyclic voltammetry. The [LiCoO2|[Li(G4)][CTFSI]|Li metal] cell showed a stable charge-discharge cycling behavior during 50 cycles, indicating that the [Li(G4)][CTFSI] complex is applicable to a 4 V class lithium secondary battery. 相似文献
906.
Hiroyuki TOBARI Masaki TANIGUCHI Mieko KASHIWAGI Masayuki DAIRAKU Naotaka UMEDA Haruhiko YAMANAKA Kazuki TSUCHIDA Jumpei TAKEMOTO Kazuhiro WATANABE Takashi INOUE Keishi SAKAMOTO 《等离子体科学和技术》2013,15(2):179-183
Vacuum insulation of 1 MV is a common issue for the HV bushing and the accel- erator for the ITER neutral beam injector (NBI). The HV bushing as an insulating feedthrough has a five-stage structure and each stage consists of double-layered insulators. To sustain 1 MV in vacuum, reduction of electric field at several triple points existing around the double-layered insulators is a critical issue. To reduce electric field simultaneously at these points, three types of stress ring have been developed. In a voltage holding test of a full-scale mockup equipped with these stress rings, 120% of rated voltage was sustained and the voltage holding capability required in ITER was verified. In the MeV accelerator, whose target is the acceleration of a H ion beam of 1 MeV, 200 A/m 2 , the gap between the grid support was extended to suppress breakdowns triggered by electric field concentration at the edge and corner of the grid support. This modi- fication improved the voltage holding capability in vacuum, and the MeV accelerator succeeded in sustaining 1 MV stably. Furthermore, it appeared that the H ions beam was deflected and a part of the beam was intercepted at the acceleration grid. This causes high heat load on the grids and breakdowns during beam acceleration. To suppress the direct interception, a new grid was designed with proper aperture displacement based on a three dimensional beam trajectory analysis. As a result, 980 keV, 185 A/m 2 H ion beam acceleration has been demonstrated, which is close to the ITER requirement. 相似文献
907.
Coal is a resource of which deposit is huge in amount, found throughout the world, and inexpensive and constant in price. For this reason, coal is expected to play a role as one of the energy supply sources in the world. The most critical issues to promote utilization of coal are to decrease the environmental load. In this report, the history, outline and recent developments of the clean coal technology in Japan, mainly the thermal power generation technology are discussed. As recent topics, here outlined first is the technology against global warming such as the improvement of steam condition for steam turbines, improvement of power generation efficiency by introducing combined generation, carbon neutral combined combustion of biomass, and carbon dioxide capture and storage (CCS) technology. Also introduced are outlines of Japanese superiority in application technology against NOx and SO2 which create acid rain, development status of the technical improvement in the handling method for coal which is a rather difficult solid‐state resource, and utilization of coal ash. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
908.
909.
The changes in the morphological structure and proteoglycan (PGs) extractability of the intramuscular connective tissues from bovine skeletal muscle exposed to high pressure (100~400 MPa) were investigated and compared to those in muscle during ageing. SDS-PAGE profiles of the PGs were also studied. During ageing, structural changes in the endomysium and perimysium occured, and disruption of the honeycomb-like structure of endomysium was observed. In the pressurized muscle, deformation of the honeycomb-like structure of endomysium was accelerated with increase of pressure applied to the muscle, and disruption of endomysium was observed in several places in the muscle pressurized at 400 MPa. Changes in the extractability of PGs were not observed in the pressurized muscle, whereas the extractability of PGs decreased with ageing. Changes in the density of the main component in the PGs with molecular mass of more than 3000 kDa on the SDS-PAGE were not observed in the PGs from the pressurized muscle, whereas the density of this band gradually decreased during the ageing. The decrease in the amounts of PGs extracted from the aged muscle seems to be due to degradation of the PGs into small dialysable molecules. From the results, it seems that high pressure treatment has some different effects on intramuscular connective tissue to ageing. ? 相似文献
910.