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141.
Shizuo Fujiwara Kozo Shirato Norio Higuchi Mizuho Maekawa Naoto Shimetani Sunao Watanabe Ikunosuke Sakurabayashi 《Analytical sciences》2008,24(6):813-815
A new apparatus has been built that annexes a normal electrocardiograph, ECG, with the aim to enhance its capacity. It adds the normal ECG power to superpose multiple records of ECG altogether and averages out them and, further, makes sophisticated analysis, such as normalizing the peak heights, evaluating the half-line widths of the peaks, or that of the standard deviations of measurements like the inter peak distances. The results of the said calculations have not been obtainable using the former instruments, and are expected to be useful for clinicians. 相似文献
142.
Jinhua Chen Masaharu Asano Yasunari Maekawa Masaru Yoshida 《Journal of polymer science. Part A, Polymer chemistry》2008,46(16):5559-5567
To prepare a crosslinked hybrid polymer electrolyte membrane (PEM) with high chemical stability, a silane monomer, namely p‐styryltrimethoxysilane (StSi), was first grafted to poly(ethylene‐co‐tetrafluoroethylene) (ETFE) film by γ‐ray preirradiation. Hydrolysis‐condensation and sulfonation were then performed on the StSi‐grafted ETFE (StSi‐g‐ETFE) films to give them crosslinks and proton conductibility, respectively. Thus, a crosslinked proton‐conducting hybrid PEM was obtained. The crosslinks introduced by the silane‐condensation have an inorganic ? Si? O? Si? structure, which enhance the chemical and thermal stabilities of the PEM. The effect of the timing of the hydrolysis‐condensation (before or after sulfonation) and the sulfonation method (by chlorosulfonic acid or H2SO4) on the properties of the resulting hybrid PEMs such as ion‐exchange capacity, proton conductivity, water uptake, chemical stability, and methanol permeability were investigated to confirm their applicability in fuel cells. We conclude that the properties of the new crosslinked hybrid StSi‐grafted PEMs are superior to divinylbenzene (DVB)‐crosslinked styrene‐grafted membranes. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5559–5567, 2008 相似文献
143.
In our previous paper [Watano S., et al., Chem. Pharm. Bull., 51(7), 747-750 (2003)], a novel compression tester, which enables the vertical and radial pressure transmission measurement, has been developed and quantitative analysis of rheo-mechanical properties of wet-mass powder prepared by different kneading times was conducted. In this study, the compression test was conducted by using the kneaded wet-mass powders prepared by different moisture contents. Pressure transmission characteristics and rheo-mechanical properties have been investigated to characterize the wet-mass powders. The relationship between these parameters and granule physical properties was also investigated. 相似文献
144.
Solid-state qubits have the potential for the large-scale integration and for the flexibility of layout for quantum computing. However, their short decoherence time due to the coupling to the environment remains an important problem to be overcome. We propose a new superconducting qubit which incorporates a spin-electronic device: the qubit consists of a superconducting ring with a ferromagnetic pi junction which has a metallic contact and a normal Josephson junction with an insulating barrier. Thus, a quantum coherent two-level state is formed without an external magnetic field. This feature and the simple structure of the qubit make it possible to reduce its size leading to a long decoherence time. 相似文献
145.
The coupling between a current and a domain wall is examined. In the presence of a finite current and in the absence of a potential which breaks the translational symmetry, there is a perfect transfer of angular momentum from the conduction electrons to the wall. As a result, the ground state is in uniform motion and this remains the case even when relaxation is included. This is described by, appropriately modified, Landau-Lifshitz-Gilbert equations. The results for a simple pinning model are compared with experiment. 相似文献
146.
Ishii K Tsutsui K Endoh Y Tohyama T Kuzushita K Inami T Ohwada K Maekawa S Masui T Tajima S Murakami Y Mizuki J 《Physical review letters》2005,94(18):187002
Mott gap excitations in the optimally doped high-T(c) superconductor YBa(2)Cu(3)O(7-delta) (T(c)=93 K) have been studied by the resonant inelastic x-ray scattering method. Anisotropic spectra in the ab plane are observed in a twin-free crystal. The excitation from the one-dimensional CuO chain is enhanced at 2 eV near the zone boundary of the b* direction, while the excitation from the CuO2 plane is broad at 1.5-4 eV and almost independent of the momentum transfer. Theoretical calculations based on the one-dimensional and two-dimensional Hubbard model reproduces the observed spectra when different values of the on-site Coulomb energy are assumed. The Mott gap of the CuO chain site is found to be much smaller than that of the CuO2 plane site. 相似文献
147.
X-ray fluorescence spectroscopy was applied to oxide glasses. Potassium Kα and Kβ lines were found to shift depending upon the rest components and the composition. These data combined with the previous data of Si Kα and Al Kα line shifts are discussed as to their relations to bond nature and bulk basicity in vitreous solids. 相似文献
148.
This paper presents a method of estimating the excess attenuation of a noise by an absorptive barrier covered with sound-absorbing materials. The approximate theory of diffraction by the absorptive barrier is derived from rigorous theory for a hard barrier. A single chart, which may be very convenient for the rapid estimation of the effect of absorption (the increase of the excess attenuation caused by the absorbing treatment of the barrier) in the practice of noise control, is presented. The validity of the method developed in this paper is confirmed by comparing estimated with measured values. 相似文献
149.
150.
3He spin relaxation time in the rotating frame (T1?) has been measured for 2% 3He in 4He solid samples of different molar volume at exchange plateau region (0.5 K). From the data, the characteristic frequency by which a 3He atom exchanges its position with a neighboring 4He atom is determined. 相似文献