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101.
Osamu Yamazaki Hideaki Yoshitake Nobuyuki Kamiya Ken-ichiro Ota 《Journal of Electroanalytical Chemistry》1995,390(1-2)
The amount of electrochemically absorbed hydrogen and lithium in a Pd cathode during electrolysis was measured quantitatively in LiOH solution. The electrode potential was also measured by the current interruption method. Inclusion of Li in Pd was found even at the potential of −0.22 V vs. RHE. This potential is far more positive than the reported UPD potential. Since Li was detected up to a depth of 200 nm, this phenomenon is not a simple UPD. The deposition of Li onto Pd and the formation of Pd---Li alloy are likely to occur at a much more positive potential than expected. The [H]/[Pd] ratio decreased gradually after 50 h electrolysis at a current density greater than 5 mA cm−2. 相似文献
102.
Takuya Kaga
Terukazu Ota
《Experimental Thermal and Fluid Science》1994,9(4):382-390Effects of surface roughness on the unsteady cavitating flow around a two-dimensional circular cylinder were experimentally investigated at Reynolds numbers from 1.36 × 105 to 1.78 × 105. Two patterns of surface roughness were investigated, a double-cut pattern and a single-cut pattern. The cavity elongates with an increase of the surface roughness, especially in supercavitating flow. However, for some roughness parameters tested, the cavity length exhibits an extreme decrease. In a particular case of the double-cut pattern, there exists the minimum cavity behind the cylinder. 相似文献
103.
It is shown that with one small exception, the 3-connected graphs admitting longest cycles that contain less than four contractible edges of the parent graph are the members of three closely related infinite families. © 1993 John Wiley & Sons, Inc. 相似文献
104.
Shinya Kanemura Koichi Matsuda Toshihiko Ota Serguey Petcov Tetsuo Shindou Eiichi Takasugi Koji Tsumura 《The European Physical Journal C - Particles and Fields》2007,51(4):927-931
We study how to incorporate CP violation in the Froggatt–Nielsen (FN) mechanism. To this end, we introduce non-renormalizable interactions with a flavor
democratic structure to the fermion mass generation sector. It is found that at least two iso-singlet scalar fields with a
discrete symmetry imposed are necessary to generate CP violation due to the appearance of the relative phase between their vacuum expectation values. In the simplest model, the
ratios of quark masses and the Cabibbo–Kobayashi–Maskawa (CKM) matrix including the CP violating phase are determined by the CKM element |Vus| and the ratio of two vacuum expectation values of FN fields, R=|R|eiα (a magnitude and a phase). It is demonstrated how the angles φi (i=1,...,3) of the unitarity triangle and the CKM off-diagonal elements |Vub| and |Vcb| are predicted as a function of |Vus|, |R| and α. Although the predicted value of the CP violating phase does not agree with the experimental data within the simplest model, the basic idea of our scenario would
be promising if one wants to construct a more realistic model of flavor and CP violation.
PACS 11.30.Er; 12.60.-i 相似文献
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109.
We employ a new laterally coupled, vertical double dot with a tunable tunnel-coupling gate in a parallel configuration to study the electron spin and orbital dependence of quantum mechanical tunnel coupling on the size of the honeycomb vertices in the small electron numbers regime. We find a transition from the weak coupling regime, where fluctuations in tunnel coupling due to varying electron configuration dominate the anticrossings, to a regime where the two dots coalesce. We apply a magnetic field to ascertain the orbital angular momenta of the Fermi surface eigenstates, which correlate with anticrossing size, and we identify spin pairs with congruent behavior. 相似文献
110.
Dan Archdeacon Joan Hutchinson Atsuhiro Nakamoto Seiya Negam Katsuhiro Ota 《Journal of Graph Theory》2001,37(2):100-114
It has been shown that every quadrangulation on any nonspherical orientable closed surface with a sufficiently large representativity has chromatic number at most 3. In this paper, we show that a quadrangulation G on a nonorientable closed surface Nk has chromatic number at least 4 if G has a cycle of odd length which cuts open Nk into an orientable surface. Moreover, we characterize the quadrangulations on the torus and the Klein bottle with chromatic number exactly 3. By our characterization, we prove that every quadrangulation on the torus with representativity at least 9 has chromatic number at most 3, and that a quadrangulation on the Klein bottle with representativity at least 7 has chromatic number at most 3 if a cycle cutting open the Klein bottle into an annulus has even length. As an application of our theory, we prove that every nonorientable closed surface Nk admits an eulerian triangulation with chromatic number at least 5 which has arbitrarily large representativity. © 2001 John Wiley & Sons, Inc. J Graph Theory 37: 100–114, 2001 相似文献