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51.
Here we propose an A(4) flavor symmetry model that implies a lower bound on the neutrinoless double beta decay rate, corresponding to an effective mass parameter M{ee} > or similar to 0.03 eV, and a direct correlation between the expected magnitude of CP violation in neutrino oscillations and the value of sin{2}theta{13}, as well as a nearly maximal CP phase delta. 相似文献
52.
Mapping Platinum Species in Polymer Electrolyte Fuel Cells by Spatially Resolved XAFS Techniques 下载免费PDF全文
Dr. Shinobu Takao Dr. Oki Sekizawa Dr. Shin‐ichi Nagamatsu Dr. Takuma Kaneko Dr. Takashi Yamamoto Dr. Gabor Samjeské Dr. Kotaro Higashi Dr. Kensaku Nagasawa Dr. Takuya Tsuji Dr. Motohiro Suzuki Dr. Naomi Kawamura Dr. Masaichiro Mizumaki Prof. Dr. Tomoya Uruga Prof. Dr. Yasuhiro Iwasawa 《Angewandte Chemie (International ed. in English)》2014,53(51):14110-14114
There is limited information on the mechanism for platinum oxidation and dissolution in Pt/C cathode catalyst layers of polymer electrolyte fuel cells (PEFCs) under the operating conditions though these issues should be uncovered for the development of next‐generation PEFCs. Pt species in Pt/C cathode catalyst layers are mapped by a XAFS (X‐ray absorption fine structure) method and by a quick‐XAFS(QXAFS) method. Information on the site‐preferential oxidation and leaching of Pt cathode nanoparticles around the cathode boundary and the micro‐crack in degraded PEFCs is provided, which is relevant to the origin and mechanism of PEFC degradation. 相似文献
53.
Prof. Yutaka Maeda Yuhei Hasuike Prof. Kei Ohkubo Atsushi Tashiro Shinya Kaneko Masayuki Kikuta Dr. Michio Yamada Prof. Tadashi Hasegawa Prof. Takeshi Akasaka Dr. Jing Zhou Prof. Jing Lu Prof. Shigeru Nagase Prof. Shunichi Fukuzumi 《Chemphyschem》2014,15(9):1821-1826
This report describes the photochemical behavior of single‐walled carbon nanotubes (SWNTs) in the presence of propylamine. The SWNTs are characterized by absorption and Raman spectroscopy. The spectral changes due to photoirradiation indicate that reactions occur predominantly with the metallic SWNTs and small‐diameter SWNTs. The detection of amine radicalcation species by ESR spectroscopy reveals photoinduced electron transfer from the amine to the excited SWNTs. After exposure of the photoirradiated SWNTs to air, the characteristic spectra were recovered, except for that of the small‐diameter SWNTs. The results suggest that, after photoreduction of the SWNTs, subsequent selective sidewall functionalization of the small‐diameter SWNTs occurs. 相似文献
54.
Junko Fukutomi Yuko Adachi Akari Kaneko Atsuomi Kimura Hideaki Fujiwara 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(1-2):115-122
The inclusion complex formation of 4-sulfothiacalix[4]arene sodium salt (STCAS) and Xe has been investigated by using hyperpolarized
129Xe NMR spectroscopy. Our new continuous-flow type hyperpolarizing system has advantageous capabilities that can supply hyperpolarized
gases continuously and directly to a sample solution in a NMR tube. Consequently saturated Xe concentration in the aqueous
solution of STCAS is maintained during the NMR experiment, and 129Xe NMR spectra can be obtained in remarkably short time. STCAS concentration dependence of 129Xe chemical shift has been analyzed in an elaborated way by a computer method as well as a simple graphic method that we have
proposed. The association constant K:13.6±0.8 M−1 at 25 °C was obtained, and further analysis of the temperature dependence has successfully given thermodynamic parameters
of enthalpy (ΔH) and entropy (ΔS) for the inclusion complex formation: ΔH = −11.9±1.9 kJ mol−1 and ΔS = −17.4±5.8 JK−1 mol−1. The energetic aspects of complex formation are discussed from the size effect and from the molecular theory of standard
entropy, and a release of definite number of water molecules from STCAS cavity is suggested in the inclusion complex formation
with Xe. 相似文献
55.
Tozuka Z Kaneko H Shiraga T Mitani Y Beppu M Terashita S Kawamura A Kagayama A 《Journal of mass spectrometry : JMS》2003,38(8):793-808
Triple-stage quadrupole (TSQ) electrospray ionization (ESI) tandem mass spectrometry (MS/MS) and ion trap ESI-MS/MS can be used to cleave protonated molecules to produce carbocations and neutral molecules in the positive ion mode. Dissociation products which correspond to protonated forms of neutral fragment molecules can also be trapped and detected. These protonated molecules in turn can cleave via carbocation cleavage, ipso cleavage, onium cleavage or McLafferty or related rearrangements. One can elucidate the structures of metabolites from the differences in m/z ratios of the fragments arising from the original drug compound and its metabolite. This strategy for structural elucidation is further facilitated by estimates of the reactivity of drugs with oxygen diradicals involved in cytochrome P-450 cycles. 相似文献
56.
M. Kaneko 《International Journal of Game Theory》1976,5(4):183-185
We provide a condition for an individual preference ordering to be represented by a function measured in terms of a commodity, i.e., for the commodity to be transferable utility. We also consider the relationships between conditions of the preference ordering and the utility function. 相似文献
57.
The effect of a geometrical relationship between a grain boundary (GB) plane and a tensile axis on intergranular fatigue cracking along 3(1 1 2) twin boundaries has been investigated in Fe-30%Cr alloy crystals. Fatigue experiments were carried out on the three kinds of the specimens containing the 3(1 1 2) twin boundary. It was found that the fatigue cracking behavior was sensitive to the geometry of the GB plane. In a specimen where both the GB plane and a slip vector lying in the GB plane in adjacent grains are inclined to the tensile axis at 45°, the fatigue cracks were nucleated preferentially along the twin boundary at a stress amplitude of 170 MPa. The specimen with the GB plane normal to the tensile axis showed that the fatigue crack was initiated from a slip band formed within a constituent grain at a stress amplitude of 300 MPa. When the GB plane was inclined to the tensile axis but the slip vector lying in the GB plane was normal to the tensile axis, development of additional slips formed perpendicular to the GB plane were observed at a specific site of the GB. Initiation of intergranular fatigue cracks at the site was recognized at a stress amplitude of 250 MPa. It can be suggested that the GB plane normal to the tensile axis provides the highest fatigue performance among them. The difference in the cracking property among these specimens could be understood in terms of the effective Schmid factor derived from elastically incompatible stress. 相似文献
58.
Hideaki Kaneko Richard D. Noren Peter A. Padilla 《Journal of Computational and Applied Mathematics》1997,80(2):351-349
In this paper, we analyse the iterated collocation method for Hammerstein equations with smooth and weakly singular kernels. The paper expands the study which began in [16] concerning the superconvergence of the iterated Galerkin method for Hammerstein equations. We obtain in this paper a similar superconvergence result for the iterated collocation method for Hammerstein equations. We also discuss the discrete collocation method for weakly singular Hammerstein equations. Some discrete collocation methods for Hammerstein equations with smooth kernels were given previously in [3, 18]. 相似文献
59.
Let mp be the minimum of the product under the conditions that and . In our previous paper [J. Kaneko, On an extremal problem of Selberg, J. Approx. Theory 142 (2006) 129–137], we showed that the following estimates hold. provided p255. In this note, we prove that the limit of as p→∞ exists and is expressed by the (unique) solution of some simultaneous transcendental equations. By using this expression we obtain numerically. 相似文献
60.
The behavior of tip vortex in an axial fan without casing wall (called open axial fan) was discussed and analyzed. The velocity measurement was performed by using two-components Laser Doppler Velocimetry (LDV) system. The detailed velocity and vorticity distribution inside blade passage and downstream of rotor were obtained. Thus the structure of tip vortex and its behavior were graphically visualized by experimental fluid dynamics (EFD). The tip vortex flow trace was indicated with the calculation of vorticity. As a result, it was found that tip vortex was generated at blade tip region near leading edge and it extended to downstream of blade exit with its core tending inward to hub direction. In addition, leading edge vortex was also found at the forepart of the experimental open fan. 相似文献