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161.
Seto M. Kitao S. Kobayashi Y. Haruki R. Mitsui T. Yoda Y. Zhang X. W. Kishimoto S. Maeda Y. 《Hyperfine Interactions》2002,141(1-4):99-108
We achieved excitation of the first excited state of 40K and confirmed both energy and lifetime. Furthermore, we observed nuclear resonant inelastic scattering by 40K in a powdered KCl sample at room temperature using a high-resolution monochromator. The time spectrum of the nuclear resonant
forward scattering was measured at 50 K. Our observations of nuclear resonant inelastic and forward scattering by 40K make electronic and dynamic studies for potassium practical. The measurements of nuclear resonant scattering for the radioactive
40K nuclide will enable and lead to further studies of other radioactive nuclides.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
162.
We construct the d-dimensional “half” Schrödinger equation, which is a kind of the root of the Schrödinger equation, from the (d+1)-dimensional free Dirac equation. The solution of the “half” Schrödinger equation also satisfies the usual free Schrödinger equation. We also find that the explicit transformation laws of the Schrödinger and the half Schrödinger fields under the Schrödinger symmetry transformation are derived by starting from the Klein-Gordon equation and the Dirac equation in d+1 dimensions. We derive the 3- and 4-dimensional super-Schrödinger algebra from the superconformal algebra in 4 and 5 dimensions. The algebra is realized by introducing two complex scalar and one (complex) spinor fields and the explicit transformation properties have been found. 相似文献
163.
Tetsuya Sengoku Yusuke Murata Hiromi Mitamura Masaki Takahashi Hidemi Yoda 《Tetrahedron letters》2012,53(4):435-437
Synthesis of a new type of mucic acid 1,4-lactone methyl ester 3-O-ferulate related to an extractive component isolated from Citrus sudachi, and its diastereomer has been achieved by employing stereodivergent dihydroxylation as a key step. The structures of the final products are fully characterized by spectroscopic methods and compared with that of the natural product. 相似文献
164.
Sengoku T Nagae Y Ujihara Y Takahashi M Yoda H 《The Journal of organic chemistry》2012,77(9):4391-4401
For the efficient approach to medicinally important α-branched 3-acyltetramic acids, the key reaction of O- to C- acyl rearrangement using α-amino-acid-derived 4-O-acyltetramic acids was extensively examined in the presence of various metal salts. Use of CaCl(2) or NaI dramatically changed the results in the reaction efficiency and rapidly brought about the desired α-branched 3-acyltetramic acids in markedly improved yields. We also discuss an epimerization at C5 stereocenter under the rearrangement conditions as well as the tolerance for structural variation at C3 and C5. In addition to the preceding success in the total synthesis of new cytotoxic tetramic acid, penicillenol A(1), this methodology could be also applied to the first total synthesis of penicillenol A(2). 相似文献
165.
Kenta Itahashi Georg P. A. Berg Hiroyuki Fujioka Hans Geissel Ryugo S. Hayano Satoru Hirenzaki Natsumi Ikeno Naohito Inabe Satoshi Itoh Daisuke Kameda Toshiyuki Kubo Hiroaki Matsubara Shinichiro Michimasa Kenjiro Miki Hiroyuki Miya Masaki Nakamura Takahiro Nishi Shumpei Noji Shinsuke Ota Ken Suzuki Hiroyuki Takeda Koichi Todoroki Kyo Tsukada Tomohiro Uesaka Helmut Weick Koichi Yoshida 《Few-Body Systems》2013,54(7-10):1569-1572
We conducted an inclusive missing-mass spectroscopy of 122Sn (d, 3He) reaction near the π¯ emission threshold at an incident energy of T d = 250 MeV/nucleon. The experiment sets its goals to the research and development of the high precision spectroscopy of pionic atoms at the RI beam factory (RIBF) of RIKEN, which precedes a new project, pionic atom factory project (piAF), to observe pionic atoms systematically. Here, we report the preliminary results of the pilot experiment. 相似文献
166.
We study the formation of deeply bound pionic atoms in the (d,3He) reaction theoretically. At different scattering angles, we find that the different subcomponents dominate the formation spectra because of the matching condition of the reaction. We also find that the pionic 1s state which is free from the residual interaction effects appears clearly in 117Sn(d, 3He) spectra. We conclude that the observation of the (d,3He) reaction for these new cases will provide more systematic and accurate information on the pionic bound states, and it will help to develop the study of the pion properties and the partial restoration of chiral symmetry in nuclei. 相似文献
167.
The effect of a light buffer gas on the anharmonic oscillation of ions trapped in a rf trap is studied. The rf resonance absorption signals showed a change of the signal height and the hysteresis with the sweep direction of the dc voltage or the probing frequency due to the anharmonicity of the pseudopotential well of a rf trap. It was found that the signals changed drastically or even disappeared depending on the pressure of buffer gas, although almost the same number of ions were trapped. These effects indicate that the sensitivity of detection of the trapped ions can be improved by appropriately choosing the pressure of the buffer gas and the sweep direction. The trapped ions could be detected until 76 h 20 min and the storage time of 1.3×105 s was determined when these parameters were optimized. 相似文献
168.
The dianion of N-phenyl-2-(phenylsulfonylmethyl)propenamide was found to be an efficient reagent for the synthesis of (E)-α,β-unsaturated amides and 5,6-dihydro-2H-pyrans. 相似文献
169.
P.-F.?ParadisEmail author J.?Yu T.?Ishikawa T.?Aoyama S.?Yoda 《Applied Physics A: Materials Science & Processing》2004,79(8):1965-1969
The density of liquid and undercooled BiFeO3 and high-temperature solid, liquid, and undercooled BaTiO3 was measured with an electrostatic levitation furnace. The density was obtained with an ultraviolet-based imaging technique that allowed excellent sample contrast throughout all phases of processing, including at elevated temperatures. Over the 1250- to 1490-K temperature range, the density of liquid BiFeO3 can be expressed as L(T)=6.70×103–1.31(T-Tm)(kgm-3) (±2 per cent) with Tm=1423 K, yielding a volume coefficient of thermal expansion L(T)=1.9×10-4 K-1. For BaTiO3, the density of the solid can be expressed as S(T)=5.04×103–0.21(T-Tm) (Tm=1893 K) over the 1220- to 1893-K range, yielding a volume coefficient of thermal expansion S(T)=4.2×10-5 K-1, whereas that of the liquid can be expressed as L(T)=4.04×103-0.34(T-Tm) over the 1300- to 2025-K range with L(T)=8.4×10-5 K-1. PACS 77.84.-s; 81.05.Je; 81.20.n 相似文献
170.
The purpose of this study is to understand the aerodynamic noise source distribution around a rotating fan blade by measuring
the noise signal and velocity field around the blade. The local noise-level distribution over the fan blade is measured by
microphone arrays, and the flow field is visualized by smoke and phase-averaged PIV measurement. The noise source distribution
is examined by cross-correlation analysis between noise signal and velocity fluctuation. It is found that the noise source
is located near the rotating fan blade, especially around leading and trailing edges. The separation and reattachment of flow
are observed near the leading edge, and the tip vortices and vortex shedding are found near the trailing edge. The cross-correlation
distribution of the noise signal and the radial velocity fluctuation shows large magnitude in the correlated regions, which
indicates the noise generation by the formation of vortex structure around the blade. 相似文献