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31.
Suzuki T Ogawa Y Chiba M Fukuda M Iwasa N Izumikawa T Kanungo R Kawamura Y Ozawa A Suda T Tanihata I Watanabe S Yamaguchi T Yamaguchi Y 《Physical review letters》2002,89(1):012501
The two-neutron removal cross section (sigma(-2n)) and the longitudinal momentum distribution of 15B fragments from the breakup of 17B on 9Be were measured at 70A MeV. The distribution in the projectile rest frame is characterized by a FWHM of 80+/-10 MeV/c for 15B. The sigma(-2n) is found to be 0.22+/-0.05 b. A Glauber-type analysis of the data provides clear evidence of a two-neutron halo structure in 17B. 相似文献
32.
M. Tanigaki M. Matsui M. Mihara M. Mori M. Tanaka T. Yanagisawa T. Ohtsubo T. Izumikawa A. Kitagawa M. Fukuda K. Matsuta Y. Nojiri T. Minamisono 《Hyperfine Interactions》1993,78(1-4):105-110
The magnetic moment of15O(I=1/2–,T
1/2=122 s) has been measured precisely by use of the -NMR detection of15O in TiO2 as, |(15O; 1/2–)|=0.71951 (12) µN. The effective nucleon mass in the nuclei around mass number 16 was discussed using the isoscalar moment deduced in connection with the magnetic moment of15N. 相似文献
33.
New determination of quadrupole coupling constants of Li isotopes in single crystals LiIO3 andLiNbO3
T. Minamisono T. Ohtsubo Y. Nakayama S. Fukuda T. Izumikawa M. Tanigaki M. Matsui S. Takeda N. Nakamura M. Fukuda K. Matsuta Y. Nojiri 《Hyperfine Interactions》1993,78(1-4):159-163
Quadrupole effects in NMR spectra of8Li(I
=2+;T
1/2=0.84 s) in LiIO3 andLiNbO3 single crystals have been detected by use of a modified -NMR. The coupling constants for both crystals are in agreement with known ones. Field gradients in the crystals were measured by detecting pulsed-Fourier transformed NMR of7Li. The quadrupole moments deduced from both samples agree, and|Q(8Li; 2+)|=32.7±0.6 mb has been determined. 相似文献
34.
Dongmei Zhou Yongnan Zheng K. Matsuta M. Mihara M. Fukuda D. Nishimura J. Komurasaki D. Ishikawa R. Matsumiya T. Nagatomo T. Izumikawa S. Takahashi H. Hirano T. Ohtsubo S. Momota Y. Nojiri A. Kitagawa M. Kanazawa M. Torikoshi S. Sato T. Minamisono J. R. Alonso G. F. Krebs T. J. M. Symons Daqing Yuan Yi Zuo Ping Fan T. Suzuki Xizhen Zhang Shengyun Zhu 《Hyperfine Interactions》2007,180(1-3):37-42
The magnetic moment of 28P (I π = 3?+?, T1/2 = 270.3 ms) in the ground state has been measured by the $\upbeta $ -nuclear magnetic resonance method for the first time. The measured magnetic moment of $\vert \upmu (^{28}$ P)∣ = 0.309(9) $\upmu _{{\rm N}}$ is well reproduced by the shell model value of +0.306 $\upmu _{{\rm N} }$ . The shell model calculation also yields a proton density distribution with a long tail. The present results provide a strong confirmation of the configuration of the 2s 1/2 proton which should lead to the proton halo. 相似文献
35.
M. Mihara K. Matsuta D. Nishimura M. Fukuda M. Yaguchi K. Iwamoto M. Wakabayashi Y. Kamisho J. Ohno Y. Morita T. Izumikawa T. Ohtsubo S. Suzuki M. Nagashima K. Abe T. Sakai S. Momota A. Ozawa D. Nagae Y. Ishibashi Y. Abe T. Niwa T. Nagatomo T. Minamisono M. K. Kubo A. Kitagawa M. Torikoshi M. Kanazawa S. Sato 《Hyperfine Interactions》2013,219(1-3):83-88
The structural and magnetic properties of Ho substituted BiFeO3 (BHFO) have been investigated using 57Fe Mössbauer spectroscopy and X-Ray diffraction (XRD) as a function of temperature. The Mössbauer spectrum obtained at room temperature for the as-synthesized BHFO sample exhibits broadened features due to the hyperfine field distributions related to the local variation of the neighbourhood of Fe and the magnetic hyperfine splitting patterns are indicative of magnetic ordering, mostly probably screwed or slightly antiferromagnetic. The spectrum was fitted with two superimposed asymmetric sextets, with similar hyperfine magnetic fields of Bhf1 = 48.0(1) T and Bhf2 = 49.0(1) T, corresponding to rhombohedral BFO. The hyperfine fields of the magnetic components decreased systematically with increasing temperature to a ‘field distribution’ just below the Néel temperature, TN ~ 600 K. At temperatures above 600 K, the spectral line associated with the Bi25FeO40 impurity phase dominates the spectra. This phase is confirmed by XRD measurements. From the temperature dependence of the site populations of the spectral components an average Debye temperature of θ D = 240(80) K has been estimated. 相似文献
36.
Izumikawa T. Matsuta K. Tanigaki M. Miyake T. Sato K. Fukuda M. Zhu S. Y. Minamisono T. 《Hyperfine Interactions》2001,136(3-8):599-605
Using β-NMR with 12B nuclei the temperature dependence of the lattice locations of boron implanted in Si is studied. At low temperature almost
100% of the implanted B is in either substitutional site or nonsubstitutional site. Above 260 K, the nonsubstitutional B rapidly
becomes undetectable and disappears at a temperature higher than 325 K due to the fast spin-lattice relaxation. Above 450
K, the fraction of substitutional B increases to 100%. These experimental results are consistently explained by the thermal
atomic jump and the dissociation of the defect associated with the nonsubstitutional B.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
37.
R. Matsumiya M. Mihara M. Ogura K. Matsuta M. Fukuda T. Izumikawa T. Minamisono 《Hyperfine Interactions》2007,178(1-3):63-67
The nuclear quadrupole interaction of short-lived β-emitter 12N(I?=?1, T 1/2?=?11 ms) implanted into a ZnO single crystal has been studied by means of the β-NMR method. We have observed a quadrupole splitting of 12N in ZnO at room temperature, from which the electric field gradient (EFG) q?=?+?(8.6 ±1.1) ×1019 V/m2 was deduced assuming axially symmetric EFG with respect to the crystalline c axis. A first principle calculation does not reproduce the data under assumption of the lattice location of 12N at the oxygen substitutional site. 相似文献
38.
Yamazaki M Izumikawa M Tachibana K Satake M Itoh Y Hashimoto M 《The Journal of organic chemistry》2012,77(11):4902-4906
Yessotoxin is a ladder-frame polyether produced by the dinoflagellate Protoceratium reticulatum. Previous labeling experiments using (13)C-acetate established the unique assembly of the carbon chain from intact and cleaved acetate units. The origins of ether and hydroxy oxygens in the molecule, which would yield further information regarding the assembly of the ladder-frame structure, have yet to be established. In this study, we describe the incorporation of (18)O in one experiment where the dinoflagellate was cultured under (18)O(2) atmosphere and in a second where the culture media was supplemented with [(18)O(2)]acetate. Labeled yessotoxin obtained from these experiments was subjected to collision-induced dissociation tandem mass spectrometry to determine the positions of (18)O-incorporation pattern in the molecule. Detailed analyses of product ions from the fragmentation processes led to the identification of (18)O-labeled positions and the incorporation ratios. The data revealed that the ether oxygens were labeled from (18)O(2) and the hydroxy oxygen on C32 was derived from [(18)O(2)]acetate. These results support a proposed biosynthetic mechanism of marine ladder-frame polyethers that a polyene precursor was oxidized by a monooxygenase after acetate condensation. 相似文献