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1.
The state of an arsenic layer electrodeposited at various potentials on platinum electrodes has been examined electrochemically. The relation between the state and the electrocatalytic activity for hydrogen evolution has been investigated. The number of vacant sites have been found to increase with lowering of the deposition potential. The activity has been found to depend not on the amount of deposited arsenic but on the number of vacant sites. The difference in the effects of arsenic and of copper on hydrogen evolution is pointed out. This is attributed to the difference in the affinity of the ad-atoms for hydrogen. 相似文献
2.
N. Hori A. Furuya M. Tsuruta F. Misaizu K. Ohno 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,43(1-3):41-44
Photoinduced dissociation in the ultraviolet region has been investigated for Ag nF n-1
+ cluster ions. Photodissociation spectrum of
Ag2F+
in the energy of 3.8–5.6 eV exhibits several sharp bands corresponding to the transition to electronically excited states.
In this dissociation, only the Ag2
+ ion was observed as a fragment ion. Theoretical calculation indicates that the parent Ag2F+ ion has a linear Ag-F-Ag equilibrium geometries in the ground and excited states. Since conformational changes by excitation
of bending vibration are necessary for the fragmentation of an F atom, this indicates that production of Ag2
+ from Ag2F+ is a result of internal conversion and following conformational changes. 相似文献
3.
4.
Tadamasa Toma Yoshio Furuya Wataru Watanabe Kazuyoshi Itoh Junji Nishii Kenichi Hayashi 《Optical Review》2000,7(1):14-17
It is known that local refractive index change occurs when femtosecond laser pulses with extremely high peak power are launched into glass. We focused 130-femtosecond laser pulses of 800 nm into the bulk of glass and examined the shape of the induced refractive index change. We found that the length of the spot of the refractive index change along the optical axis reached about 30 μm despite the diameter being about 2 μm. To estimate the distribution of induced refractive index change, we fabricated Bragg grating by scanning the focused spot and calculated the amount of the change by applying Kogelnik’s coupled mode theory to the measured diffraction efficiencies of the higher order diffracted beams. 相似文献
5.
Self-injection length in La0.7Ca0.3MnO3-YBa2Cu3O7-δ ferromagnet-superconductor multilayer thin films
We have carried out extensive studies on the self-injection problem in barrierless heterojunctions between La0.7Ca0.3MnO3 (LCMO) and YBa2Cu3O7-δ (YBCO) thin films. The heterojunctions were formed in situ by sequentially growing LCMO and YBCO films on 〈100〉 LaAlO3 (LAO) substrate using a pulsed laser deposition (PLD) system. YBCO micro-bridges with 64 μm width were patterned both on
the LAO (control) and LCMO side of the substrate. Critical current, I
c, was measured at 77 K on both the control side as well as the LCMO side for different YBCO film thickness. It was observed
that while the control side showed a J
c of ∼ 2 × 106 A/cm2, the LCMO side showed about half the value for the same thickness (1800 ?). The difference in J
c indicates that a certain thickness of YBCO has become ‘effectively’ normal due to self-injection. From the measurement of
J
c at two different thicknesses (1800 ? and 1500 ?) of YBCO films both on the LAO as well as the LCMO side, the value of self-injection
length (at 77 K) was estimated to be ∼ 900 ?. To the authors’ best knowledge, this is the first time that self-injection length
has been quantified. A control experiment carried out with LaNiO3 deposited by PLD on YBCO did not show any evidence of self-injection. 相似文献
6.
Mamoru Furuya Hiroshi Niitsuma 《Proceedings of the American Mathematical Society》2004,132(11):3189-3193
We introduce the concept of -adic -basis as an extension of the concept of -basis. Let be a regular local ring of prime characteristic and a ring such that . Then we prove that is a regular local ring if and only if there exists an -adic -basis of and is Noetherian.
7.
A new model of the core-nucleus and two-neutron system is introduced. The Faddeev equations of the 6He-n-n, 8He-n-n and 9Li-n-n systems for 8He, 10He and 11Li are solved, respectively. The potential of the subsystem in the model has been constructed to make couplings of the ground state and the excited one inside the core-nucleus. Simple rank one separable Yamaguchi-type potentials between the core-nucleus and neutron are employed with the coupling strength determined from the energy levels and width. We solve the Faddeev three-cluster equations to obtain the low-lying energy levels of 8He, 10He and 11Li. In order to understand the nuclear structures we calculate some inner wave functions and probabilities. 相似文献
8.
Minghui Song Kazutaka Mitsuishi Kazuo Furuya 《Physica E: Low-dimensional Systems and Nanostructures》2005,29(3-4):575
Nanometer-sized W-dendrites are fabricated on Al2O3 substrates with an electron-beam-induced deposition process. Dependence of growth of nanodendrite on surface topography is investigated with transmission electron microscopy. It is confirmed that the nanodendrite grows on convex surfaces but not around a hole on a substrate. These are attributed to different distribution of charges on surfaces with different topographies during electron beam irradiation when charges are produced on the surface due to emission of second electrons. The charges accumulate on convex surface and do not distribute around a hole. Therefore, the nanodendrite grows on the former and not on the latter. 相似文献
9.
10.
An \({\alpha}\)–n–n three-cluster model of the \({^6}\)He nucleus is studied by solving the Faddeev equations, where the cluster potential between \({\alpha}\) and n takes into account the Pauli exclusion correction, using the Fish-Bone Optical Model (Schmid in Z Phys A 297:105, 1980). The resulting binding energy of the ground state (\({0^+}\)) is 0.831 MeV and the resonance energy of the first excited state (\({2^+}\)), 0.60–i0.012 MeV, is extracted from the three-cluster break-up threshold. These theoretical values are in reasonable agreement with the experimental data: 0.973 MeV and 0.824–i0.056 MeV, respectively. In order to investigate the structure of these states, we calculate the angle density matrix for the \({\angle n_1 \alpha n_2}\) angle in the triangle formed by the three clusters. The angle density matrix of the ground state has two peaks and the configuration of \({0^+}\) wave function corresponding to the peaks constitutes a mixture of an acute-angled triangle structure and an obtuse-angled one. This finding is consistent with the former result from a variational approach (Hagino and Sagawa in Phys Rev C 72:044321, 2005). On the other hand, in the case of \({2^+}\) state only a single peak is obtained. 相似文献