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281.
Takashi Manago Kazuya Kanazawa Tatsuya Kera 《Journal of magnetism and magnetic materials》2009,321(15):2327-2330
The anisotropic magneto-resistance (AMR) contributions of a zigzag-shaped NiFe wire were investigated. The magneto-resistance (MR) behaviors in different magnetic-field directions clearly reflect the angular relationships between the directions of the current and magnetic moment in the subdivisions. The resistance in remanence after magnetization along 0° in respect to the longer direction of zigzag was larger than that along 90°. Assumed that the difference appears due to the AMR contribution in the domain wall trapped at the corner, the MR ratio was estimated to be 1.2%, which is in good agreement with the AMR of the NiFe film. We clearly showed that the domain-wall resistance originates in the AMR. 相似文献
282.
In order to get a clue to understanding the volume-dependence of vortex free energy (which is defined as the ratio of the twisted against the untwisted partition function), we investigate the relation between vortex free energies defined on lattices of different sizes. An equality is derived through a simple calculation which equates a general linear combination of vortex free energies defined on a lattice to that on a smaller lattice. The couplings in the denominator and in the numerator however shows a discrepancy, and we argue that it vanishes in the thermodynamic limit. Comparison between our result and the work of Tomboulis is also presented. In the appendix we carefully examine the proof of quark confinement by Tomboulis and summarize its loopholes. 相似文献
283.
Kiriyama H Mori M Nakai Y Shimomura T Tanoue M Akutsu A Kondo S Kanazawa S Okada H Motomura T Daido H Kimura T Tajima T 《Optics letters》2008,33(7):645-647
We report a high-contrast, high-intensity Ti:sapphire chirped-pulse amplification system that incorporates a nonlinear preamplifier based on optical parametric chirped-pulse amplification (OPCPA). By cooling the Ti:sapphire crystal in the final amplifier down to 77 K, the chirped-pulses are amplified to 2.9 J at a 10 Hz repetition rate without a thermal lensing effect. Pulse compression down to 19 fs duration obtained after amplification indicates a peak power of 80 TW. With the OPCPA, the temporal contrast is significantly improved to better than 7x10(-9) in a few picoseconds interval prior to the main laser pulse. 相似文献
284.
Cecilia Cerretani Hiroki Kanazawa Tom Vosch Jiro Kondo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(48):17313-17317
DNA has been used as a scaffold to stabilize small, atomically monodisperse silver nanoclusters, which have attracted attention due to their intriguing photophysical properties. Herein, we describe the X‐ray crystal structure of a DNA‐encapsulated, near‐infrared emitting Ag16 nanocluster (DNA–Ag16NC). The asymmetric unit of the crystal contains two DNA–Ag16NCs and the crystal packing between the DNA–Ag16NCs is promoted by several interactions, such as two silver‐mediated base pairs between 3′‐terminal adenines, two phosphate–Ca2+–phosphate interactions, and π‐stacking between two neighboring thymines. Each Ag16NC is confined by two DNA decamers that take on a horse‐shoe‐like conformation and is almost fully shielded from the solvent environment. This structural insight will aid in the determination of the structure/photophysical property relationship for this class of emitters and opens up new research opportunities in fluorescence imaging and sensing using noble‐metal clusters. 相似文献
285.
Although a free rotation around a single bond gives no mechanical output, it has let us imagine a molecular motor. A para-substituted aromatic ring can be regarded as a rotator with the para-rotation axis. When it is incorporated in a wider pi-conjugated system, a quinoidal structure is generated accompanied by oxidation on the substituted groups at the 1,4-position, and the axis is fixed. A paraphenylenediamine was selected as the nanomechanical molecular module capable of locking and releasing the free rotation using an electrode in solution. We inserted the module into a simple molecular system, cyclophane. It was clarified that the cyclophane was able to open and close its cavity in a reversible redox process repeatedly. 相似文献
286.
T. Oguchi I. Kanazawa T. Iwashita We-Hyo Soe A. Yamaguchi R. Yamamoto 《Journal of Non》1992,150(1-3):448-451
The time differential perturbed angular correlation spectra of the Cu---Hf multilayers and the change in the spectra during the amorphous phase change have been measured. The mechanism for the phase change of the multilayers is discussed. 相似文献
287.
Dipolar correlation functions of acetone in various solvents are obtained by Fourier transform of infrared spectra. The analysis of the shapes of correlation functions shows that the reorientational process is diffusional in the time scale longer than about 0.3 × 10?12 sec. In nonpolar solvents the ratios of correlation times τA : τB : τC do not vary in different solvents, and the reorientation around b axis is more restricted than around the other axis. The length of correlation time is dependent on the density of solvent rather than the viscosity. These observations are unexpected if only the electrostatic interaction is considered. In polar solvents correlation times are longer than in nonpolar solvents and the tendency is especially remarkable in τB. An electrostatic interaction between polar molecules seems to be responsible for these observations. The solvent effect on the frequency shifts of carbonyl stretching vibration is consistent with the result of correlation times. 相似文献
288.
Summary Octadecyl-porous glass was prepared and used as the packing for reversed-phase high-performance liquid chromatography. A mixture
of ginsenosides, saponins of ginseng was analyzed with detection at 203 nm. Ginsenosides Rf, Rg2, Rb1, Rc, Rb2, and Rd were separated with acetonitrile-water (27.5:72.5) as the mobile phase. A well-resoluted chromatogram of ginsenosides
Ro, Rg1 and Re was also obtained with acetonitrile-water (16.5:83.5). The whole separation was achieved in 12 min with a flowrate
of 1 ml/min. Calibration curves of ginsenosides Rb1, Rc, Rb2, Rd, Rg1 and Re were linear up to 5 μg. It can be concluded that the rapid and accurate analysis of ginsenosides is possible by the
described method. 相似文献
289.
Mesopores created by platinum nanoparticles in zeolite crystals 总被引:1,自引:0,他引:1
Kato H Minami T Kanazawa T Sasaki Y 《Angewandte Chemie (International ed. in English)》2004,43(10):1251-1254
290.
T. Nagatomo K. Matsuta Y. Nakashima T. Sumikama M. Ogura K. Akutsu T. Iwakoshi H. Fujiwara T. Minamisono M. Fukuda M. Mihara T. Miyake K. Minamisono S. Momota Y. Nojiri A. Kitagawa M. Sasaki M. Torikoshi M. Kanazawa M. Suda M. Hirai S. Sato S. Y. Zhu J. Z. Zhu Y. J. Xu Y. N. Zheng J. R. Alonso G. F. Krebs T. M. Symons 《Hyperfine Interactions》2004,159(1-4):273-276
The momentum dependences of the nuclear spin polarization P and alignment A of 13B(, T
1/2 = 17.36 ms) produced in the 100A MeV 15N + Be collisions have been measured by detecting β-ray asymmetry. Because both the P and A were significantly smaller than the prediction from a simple kinematical model, some relaxation mechanisms must be take into
account. Comparing the signs of the observed alignment of 12B, the sign of the quadrupole coupling constant eqQ of 13B in TiO2 was determined to be positive. 相似文献