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151.
Yoshihiro Takahashi Takashi Kitamura Kenji Uchida Masao Tomura 《Journal of luminescence》1981,22(3):267-271
Emission decay times of the new excimer were measured for undoped and perylene doped pyrene crystals. From the decay times obtained, the temperature dependence of the diffusion coefficient of the excimers was deduced by assuming a model in which two electronic states of the new excimer are involved in the energy transfer process. Within this model, it was found that in the upper excimer state the excimers migrated by a hopping process, while in the lower excimer state they migrated as free excimer excitons while undergoing phonon scattering. 相似文献
152.
T. Nagatomo H. Ueno M. Mihara K. Matsuta A. Yoshimi Y. Ichikawa K. Yamada H. Kawamura A. Ozawa T. Moriguchi Y. Ishibashi K. Asahi M. Uchida K. Suzuki T. Inoue Y. Hasama H. Iijima T. Sumikama M. Fukuda T. Minamisono 《Hyperfine Interactions》2010,198(1-3):103-107
Electric quadrupole coupling constant eqQ/h of the extremely proton-rich 23Al (I π ?=?5/2?+?, T 1/2?=?0.47 s) nucleus implanted into an Al2O3 single crystal has been measured for the first time, using the β-ray detecting nuclear quadrupole resonance method (β-NQR) in a high magnetic field. As a preliminary result, the quadrupole coupling constant was determined as |eqQ/h(23Al) |?=?2.66±0.77 MHz. Using the quadrupole coupling constant of 27Al in Al2O3 as a reference, the Q moment of the ground state of 23Al was extracted as |Q(23Al)|?~?160 mb, which is well explained by the shell model calculation in the sd-shell model space with the USD interaction. 相似文献
153.
It was founded using the magneto-optical technique that the domain wall in the iron-based amorphous ferromagnet in its movement experienced enhanced deceleration on the surface compared to the volume. The surface deceleration of the wall intensifies under water molecules adsorption on the sample surface. This effect is explained by the domain wall interaction with magnetic micro-defects observed on the sample surface using a magnetic force microscope. 相似文献
154.
155.
H. Iwasawa J.F. Douglas K. Sato T. Masui Y. Yoshida Z. Sun H. Eisaki H. Bando A. Ino M. Arita K. Shimada H. Namatame M. Taniguchi S. Tajima S. Uchida T. Saitoh D.S. Dessau Y. Aiura 《Physica C: Superconductivity and its Applications》2010
Using angle-resolved photoemission spectroscopy (ARPES) with low-energy tunable photons, we studied the oxygen isotope effect in optimally doped Bi2Sr2CaCu2O8+δ (Bi2212). We found the oxygen isotope shift in the real part of the electron self-energies [ReΣ(ω)s] along the nodal direction derived not only from the momentum distribution curves (MDCs) but also from the energy distribution curves (EDCs). Present results indicate straightforwardly the coupling between the nodal electrons and the phonons. 相似文献
156.
Uchida H Song JM Suzuki S Nakazawa E Baba N Watanabe M 《The journal of physical chemistry. B》2006,110(27):13319-13321
To confirm the superiority of newly developed electrocatalyst layer (ECL) for polymer electrolyte fuel cells, three-dimensional dispersion states of Nafion ionomer in Pt/carbon black agglomerates were analyzed by electron tomography based on multiple TEM images taken at different tilt angles. Uniform distribution of the ionomer has been first observed, proving the high catalyst utilization in the new ECL distinctive from that of the conventional one. 相似文献
157.
[Structure: see text] The morphinan skeleton was effectively synthesized by an intramolecular Mannich-type reaction. Further transformation led to total synthesis of morphine. 相似文献
158.
In the atomic absorption spectrometry with the long absorption tube using a hydrogen-air flame, only the total consumption type of the burners, e.g., Beckman1 or ring burners2, have been used for the input of a sample solution to the flame. The use of the indirect input method with nebulization chamber has never been attempted, though, by use of a commercially available apparatus with nebulization chamber, the large increase of the sensitivity has been easily obtained by heating the chamber and nebulizing air3–5. 相似文献
159.
M. Uchida 《Few-Body Systems》2013,54(7-10):947-953
Recent activities of the Belle experiment in Hadron spectroscopy are presented. The discovery of two charged bottomonium-like particles, ${Z_b^{\pm}(10610)}$ and ${Z_b^{\pm}(10650)}$ in the ${\Upsilon (nS)\pi^{\pm}}$ (n = 1, 2, 3) and h b (m P)π ± (m = 1, 2) final states is followed by the observation of the corresponding peaks in the ${B^*\bar{B}^{(*)}}$ final states that favors the molecular interpretation of Z b . In addition, a neutral partner candidate is explored at 10,610 MeV in the ${\Upsilon (2S)\pi^0}$ mass spectrum projection. We have got no evidence of an X(3872) partner in J/ψ π ± π 0, J/ψ η and ${\chi_{c1,2}\gamma}$ final states while an evidence of the narrow peak at 3,823 MeV/c 2 in ${\chi_{c1}\gamma}$ is thought to be 3 D 2 charmonium (ψ 2) candidate. The feasibilities of the search for X(3872) partner in the B → J/ψ π 0 π 0 K decays, the measurement of light flavored baryons production cross section, and the study of K–p interaction in ${\phi p}$ final state are also discussed. 相似文献
160.
T. Kawabata T. Adachi M. Fujiwara K. Hatanaka Y. Ishiguro M. Itoh Y. Maeda H. Matsubara H. Miyasako Y. Nozawa T. Saito S. Sakaguchi Y. Sasamoto Y. Shimizu T. Takahashi A. Tamii S. Terashima H. Tokieda N. Tomida T. Uesaka M. Uchida Y. Yasuda N. Yokota H. P. Yoshida J. Zenihiro 《Few-Body Systems》2013,54(1-4):93-97
The alpha inelastic scattering from 24Mg was measured to obtain the isoscalar natural-parity excitation strengths and to search for the α-condensed states. The multipole decomposition analysis for the measured cross sections was performed. The strength distributions for the ${{\Delta}L=0{-}3}$ were successfully obtained and the possible candidates for the α-condensed states around the 16O core were found. 相似文献