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711.
A stable Ru(II)/Ru(III) mixed-valence state was observed in acetonitrile for the ruthenium binuclear complex bridged by dimercaptothiadiazolate (DeltaE(1/2) = 220 mV for Ru(2)(II,II)/Ru(2)(II,III) and Ru(2)(II,III)/Ru(2)(III,III) processes; K(com) = 5.3 x 10(3)). Upon protonation of the bridging ligand by the addition of equimolar p-toluenesulfonic acid, however, the mixed-valence state diminished (DeltaE(1/2) = 0 mV). The bridging ligand operates as a proton-induced switch of the electronic communication in the dimeric complex. 相似文献
712.
The finite-difference time-domain (FDTD) method is applied to the numerical evaluation of diffraction from a binary relief grating with subwavelength structures. It is demonstrated numerically that the binary relief grating made of isotropic materials works as a polarization selective optical device. It is further shown that the polarization effects depend on the arrangements of subwavelength structures. 相似文献
713.
714.
Norimichi Tsumura Hideki Sato Takayuki Hasegawa Hideaki Haneishi Yoichi Miyake 《Optical Review》1999,6(1):57-61
A new technique is proposed to improve the way of selecting samples used to estimate spectral reflectance from sensor responses in multi-band images. This technique limits the samples of reflectance spectra based on the spectral reflectance estimated by the conventional estimation method, and estimates it again using the limited samples. Vector angle and distance among reflectance spectra as the criteria for the limitation can be applied to improve the estimation of reflectance spectra. 相似文献
715.
Yoichi Uetake 《Integral Equations and Operator Theory》2008,60(2):271-288
We construct a Lax-Phillips scattering system on the arithmetic quotient space of the Poincaré upper half-plane by the full
modular group, based on the Eisenstein transform. We identify incoming and outgoing subspaces in the ambient space of all
functions with finite energy-form for the non-Euclidean wave equation. The use of the Eisenstein transform along with some
properties of the Eisenstein series of two variables enables one to work only on the space corresponding to the continuous
spectrum of the Laplace-Beltrami operator. It is shown that the scattering matrix is the complex function appearing in the
the functional equation of the Eisenstein series of two variables. We obtain a compression operator constructed from the Laplace-Beltrami
operator, whose spectrum consists of eigenvalues that coincide, counted with multiplicities, with the non-trivial zeros of
the Riemann zeta-function. For this purpose we construct and use a scattering model on the one-dimensional Euclidean space.
相似文献
716.
Naohiko Shimada Tadashi Okobira Yoichi Takeda Seiji Shinkai Kazuo Sakurai 《Journal of polymer science. Part A, Polymer chemistry》2008,46(4):1440-1448
Schizophyllan (SPG) is a natural β‐1,3‐glucan that forms a triple helix (t‐SPG) in neutral aqueous solutions and t‐SPG can be denatured to single chains (s‐SPGs) in DMSO or alkaline solutions. Exchanging the denatured solutions for neutral water leads the renaturation of the triple helix. We have reported that hydrophobic molecules can form a complex with s‐SPG when they are present in the renaturation process. Some of these, for example poly(dA) and polyaniline, were found to have aromatic amino moieties. This report demonstrates whether s‐SPG can interact with other aromatic amino compounds such as anilinonaphthalene sulfonic acid (ANS) derivatives. Enhanced fluorescence intensity and red‐shifted UV absorption spectra were observed in the mixture of s‐SPG and 2,6‐ANS or 2,6‐TNS. In the circular dichroism measurement, the positive Cotton effects appeared after mixing 2, 6‐ANS with s‐SPG. When the amino proton was replaced by the methyl group or used in intramolecular hydrogen bonds, any spectral changes were not observed. These results indicate that amino proton in the ANS derivatives plays a key role in the complexation. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1440–1448, 2008 相似文献
717.
Shin‐Ichi Hirota Yoichi Tominaga Shigeo Asai Masao Sumita 《Journal of Polymer Science.Polymer Physics》2005,43(21):2951-2962
An in situ dielectric measurement for atactic poly(methyl methacrylate) (at‐PMMA) was performed under high‐pressure CO2 under various pressures and temperatures. The at‐PMMA has the acetate side group with a large dipole moment. In the glassy state, a local relaxation process (β‐process) can be observed using dielectric measurement. In the rubbery state, the micro‐Brownian motion of main chain (α‐process) occurs, and the β‐process changes into αβ‐process coordinated with the α‐process. The dielectric loss (ε″) spectrum of at‐PMMA in the glassy state is asymmetric because of the density fluctuation for the amorphous structure. The loss peak frequency shifted to higher frequencies, and the relaxation strength increased with increasing CO2 pressure. In the glassy state, the shape of ε″ spectrum became more symmetric with increasing CO2 pressure. These show that the molecular mobility enhanced by the plasticization effect of CO2 allows the dipolar side groups in the high‐density region to contribute to the relaxation process. We also found that the apparent activation energy decreased under high‐pressure CO2. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2951–2962, 2005 相似文献
718.
We evaluate the adsorption of SO3 molecule on the Pt (1 1 1) surface using the first-principles calculations by a slab model with a periodic boundary condition. We find that there are four stable adsorption configurations on the Pt surface, where SO3 molecules are adsorbed above the three-fold fcc and hcp sites. In two of these configurations, S and two O atoms are bound to the Pt atoms, and in two other of them, all the three O atoms are bound to Pt surface atoms. Besides, it is found that molecular orbitals of SO3 and those of Pt surface are hybridized in the active metal d-bands region, that the localized molecular orbitals in SO3 are stabilized, and that the charge is transferred from Pt to S 3p by SO3 adsorption on Pt surface though the other interaction of S and O (bound to Pt) component with Pt is little. In addition, the bond between S and O bound to Pt become weak by SO3 adsorption on Pt surface because the charge polarization to O-Pt bond weakens the bond between S and O bound to Pt. This interaction is assumed to encourage the breakage of S-O bond. 相似文献
719.
Shigeki Yoshida Koji Suizu Yoichi Nakagomi Kodo Kawase 《Journal of Molecular Spectroscopy》2009,256(1):146-198
Metallic meshes work as band-pass filters in the terahertz (THz) region, with their transmission spectra acutely affected by the refractive index of the material inside and above the metallic-mesh openings. We used a metallic mesh for high-sensitivity observations by focusing on the “dip,” that is, a sudden change in transmittance that only appeared when the THz wave was obliquely incident onto the metallic mesh. Here we consider the interference between apertures of the metallic mesh in the diagonal direction and explain the dip using finite-difference time-domain (FDTD) electromagnetic simulations. 相似文献
720.
Eunji Lee In‐Hyeok Park Huiyeong Ju Seulgi Kim Jong Hwa Jung Yoichi Habata Shim Sung Lee 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(33):11418-11422
A one‐pot reaction of the A1/A2‐thiopyridyl pillar[5]arene L with silver(I) trifluoroacetate in the presence of the linear dinitrile guest C8 , [CN(CH2)nCN, n=8], afforded the first example of a two‐dimensional (2D) poly‐pseudo‐rotaxane {[(μ4‐Ag)2( C8 @ L )2(μ ‐C8 )](CF3CO2)2}n. Surprisingly, in this structure the C8 guest not only threads into the pillar[5]arene unit but also crosslinks the 1D coordinative polymeric arrays. The formation of the 2D poly‐pseudo‐rotaxane is driven by an adaptive rearrangement of the components that minimizes the steric clashes not only between the threaded guests but also between the threaded and crosslinked guests where crosslinking occurs. A pathway for the formation of the 2D poly‐pseudo‐rotaxane is proposed. 相似文献