Permutation Symmetry S_3 and VEV Structure of Flavor-Triplet Higgs Scalars

A model with flavor-triplet Higgs scalars \phi_i (i=1,2,3)is investigated under a permutation symmetry S_3 and its symmetry breaking. A possible S_3 breaking form of the Higgs potential whose vacuum expectation values v_i=< \phi_i> satisfy a relation v_1^2 +v_2^2 +v_3^2 ={2/3}(v_1 +v_2 +v_3)^2 is investigated, because if we suppose a seesaw-like mass matrix model M_e = m M^{-1} m with m_{ij} \propto \delta_{ij} v_i and M_{ij} \propto \delta_{ij}, such a model can lead to the well-known charged lepton mass relation m_e +m_\mu +m_\tau = {2/3} (\sqrt{m_e}+\sqrt{m_\mu} +\sqrt{m_\tau})^2.Comment: 7 pages, 1 figure, final version to appear in PR

Charged Lepton Mass Formula -- Development and Prospect --

The recent devolopment on the charged lepton mass forumula m_e+m_{\mu}+m_{\tau}={2/3}(\sqrt{m_e}+\sqrt{m_\mu}+\sqrt{m_{\tau}})^2 is reviewed. An S_3 or A_4 model will be promising for the mass relation.Comment: Latex, 11 pages, no figure, Talk at Internationa Workshop on Neutrino Masses and Mixing, at Shizuoka, Japan, December, 17-19, 200

S_4 Flavor Symmetry Embedded into SU(3) and Lepton Masses and Mixing

Based on an assumption that an S_4 flavor symmetry is embedded into SU(3), a lepton mass matrix model is investigated. A Frogatt-Nielsen type model is assumed, and the flavor structures of the masses and mixing are caused by VEVs of SU(2)_L-singlet scalars \phi_u and \phi_d which are nonets (8+1) of the SU(3) flavor symmetry, and which are broken into 2+3+3' and 1 of S_4. If we require the invariance under the transformation (\phi^{(8)},\phi^{(1)}) \to (-\phi^{(8)},+\phi^{(1)}) for the superpotential of the nonet field \phi^{(8+1)}, the model leads to a beautiful relation for the charged lepton masses. The observed tribimaximal neutrino mixing is understood by assuming two SU(3) singlet right-handed neutrinos \nu_R^{(\pm)} and an SU(3) triplet scalar \chi.Comment: 12 pages, no figure, to appear on JHE

Slow Morphological Change of Perfluorinated Ionomer as Deduced From 1H NMR Spectra of Confined Water

The behaviour of water molecules confined in the perfluorinated ionomer membrane, which is widely used for polymer electrolyte fuel cells, was investigated by 1H NMR spectroscopy. The 1H NMR spectra of water molecules confined in the membrane presented characteristic features depending on temperature and hydrated conditions. On the basis of the observations of the variations in the 1H NMR signals, it was deduced that the polymer underwent very slow conversions among distinct morphologies depending on temperatures and humidified conditions below 348 K. A plausible scheme of the local conversion of the states of the water molecules associated with the morphological changes of the polymer was proposed

Estimation of water contents of polymer electrolytes by 1H NMR spectroscopy

Water molecules confined in perfluorinated ionomer membranes which are widely used for polymer electrolyte fuel cells, presented apparently a single 1H NMR peak in hydrated states because of the rapid exchange among the water molecules at the distinct segments of the polymer. The peak shifted to the lower field with decreasing the water content due to the decrease of the fraction of the bulk water molecules which present a peak at higher field. The chemical shifts were found to be well correlated with the peak area. The water peak for MEA (Membrane Electrode Assembly) showed also similar behaviors to the membranes. From the relationship between the chemical shift and the peak area of the confined water peak we demonstrated the potential that the chemical shift could be utilized to estimate the water content in the hydrated membranes and MEA

Enhancing the Superconducting Transition Temperature due to Strong-Coupling Effect under Antiferromagnetic Spin Fluctuations in CeRh1-xIrxIn5 : 115In-NQR Study

We report on systematic evolutions of antiferromagnetic (AFM) spin fluctuations and unconventional superconductivity (SC) in heavy-fermion (HF) compounds CeRh$_{1-x}$Ir$_{x}$In$_5$ via $^{115}$In nuclear-quadrupole-resonance (NQR) experiment. The measurements of nuclear spin-lattice relaxation rate $1/T_1$ have revealed the marked development of AFM spin fluctuations as a consequence of approaching an AFM ordered state with increasing Rh content. Concomitantly the superconducting transition temperature $T_{\rm c}$ and the energy gap $\Delta_0$ increase drastically from $T_{\rm c} = 0.4$ K and $2\Delta_0/k_{\rm B}T_{\rm c} = 5$ in CeIrIn$_5$ up to $T_{\rm c} = 1.2$ K and $2\Delta_0/k_{\rm B}T_{\rm c} = 8.3$ in CeRh$_{0.3}$Ir$_{0.7}$In$_5$, respectively. The present work suggests that the AFM spin fluctuations in close proximity to the AFM quantum critical point are indeed responsible for the onset of strong-coupling unconventional SC with the line node in the gap function in HF compounds.Comment: 4pages,5figures,to appear in Phys. Rev. Let

The Effect of Platinum Deposition on the Water Photo-Reduction at p-Cu2O Semiconductor Electrodes with Visible Light Irradiation

The surface of a p-Cu2O semiconductor photoelectrode was modifi ed by electrodeposition of Pt nanoparticles and analyzed by XRD, SEM, XPS, and EIS (electrochemical impedance spectrometry) methods besides photocurrent measurements. The XRD, SEM, and XPS analyses showed the fabrication of Cu2O fi lm and the deposition of Pt particles. On the electrodeposition of Pt nanoparticles, cathodic photocurrent was enhanced. The EIS analysis suggested that Pt nanoparticles enhance the charge transfer process to the solution

Indikasi Kerusakan Dingin pada Mentimun Jepang (Cucumis Sativus L.) Berdasarkan Perubahan Ion Leakage dan PH

In this study, the chilling induced in Japanese cucumber (Cucumis sativus L.) stored at chilled temperature and the changes in its quality during storage period were examined. Change in ion leakage and pH were used as indicator of chilling injury symptopms. The sample of cucumber were stored at 5ºC (chilling) and 25ºC (non chilling). Percentage of ion leakage for cucumber stored at 5ºC was higher than that at 25 ºC at storage time of 3, 6 and 9 days. The increase in the rate of ion leakage at 5ºC indicates the chilling induced of cell membrane. The increasing tendency of pH was observed for cucumber stored at 5ºC with the value at storage time of 9 days were higher than that at 25ºC. The increase in pH could be thought as the change in acid content which indicate the occurrence of chilling injury. Changes in ion leakage and pH indicate the change in membrane permeability which related to chilling injury