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511.
Structures of amorphous anodic alumina films have been investigated by the X-ray radial distrubution function and the correlation method. The amorphous anodic alumina films are considered to contain AlO5 coordination polyhedra as well as AlO4 tetrahedra and AlO6 octahedra. Two types of conformation are taken into account by the correlation method; one (model A) is the conformation in which the above coordination polyhedra are arranged in a similar way to that found in the crystalline modifications of γ-Al2O3 within a short range of r < 4.5 Å and the other (model B) is the conformation in which coordination polyhedra are randomly arranged. The final model formed by mixing these two conformations (model A and B) in 1 : 1 ratio describes quantitatively the observed scattering intensity curves of the amorphous anodic alumina films. 相似文献
512.
Spectroscopic polarimetry with a channeled spectrum 总被引:1,自引:0,他引:1
We describe a novel method for the spectroscopic measurement of the state of polarization (SOP) of light. A pair of thick birefringent retarders is incorporated into the spectroscopic polarimeter, so the generated channeled spectrum is composed of three quasi-cosinusoidal components carrying the information about the SOP of the light that is being measured. Fourier inversion of the channeled spectrum provides significant parameters for determination of the spectrally resolved Stokes parameters of light. No mechanically movable components for polarization control or active devices for polarization modulation are used, and all the Stokes parameters can be determined at once from only the single spectrum. The effectiveness of this method is demonstrated by the generation of elliptically polarized light whose SOP varies with wave number. 相似文献
513.
S. Kawasaki T. Oka X.F. Wang Guo-qing Zheng 《Journal of Physics and Chemistry of Solids》2011,72(5):501-504
75As-zero-field nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) measurements are performed on CaFe2As2 under pressure. At P=4.7 and 10.8 kbar, the temperature dependence of nuclear-spin-lattice relaxation rate (1/T1) measured at tetragonal phase show no coherence peak just below Tc and decrease with decreasing temperature. The superconductivity is of gapless at P=4.7 kbar but evolves to multiple gaps at P=10.8 kbar. We find that the superconductivity appears near a quantum critical point. Both electron correlation and superconductivity disappear in the collapsed tetragonal phase. A systematic study under pressure indicates that electron correlations play a vital role in forming Cooper pairs in this compound. 相似文献
514.
After preparing a homologous series of tetrameric mesogenic compounds in which two U-shaped molecules were connected via a rigid benzene derivative or a flexible alkyl chain, we investigated their phase transition behaviour using optical microscopy, differential scanning calorimetry and X-ray diffraction analysis. The compounds possessing an alkyl spacer as the central group exhibited nematic and smectic A phases just as the corresponding U-shaped molecule did. The compound possessing a 1,2-benzene unit as the connecting group showed nematic and smectic A phases, although the compound possessing a 1,3-benzene unit exhibited only an anticlinic smectic C phase. Structure–property relations of the liquid crystalline tetramers are interpreted in terms of preorganised effects of the four mesogenic units. 相似文献
515.
Hiroshi Ugajin Norio Oka Toru Okamoto Haruma Kawaguchi 《Colloid and polymer science》2013,291(1):109-115
We developed a novel type of protein molecule-imprinted particles. Bovine hemoglobin (BHb) and submicron-sized polymer particles were used in this study as a template and a substrate, respectively. BHb molecules were softly and sparsely adsorbed on the particle surface. Then skin layer was formed with a thickness of BHb molecule size by living radical graft polymerization of moderately hydrophilic monomers. After that, BHb molecules were removed from their embedded spaces. The ability of vacant spaces on the surface layer of particles to take BHb molecules selectively was examined. Successful results were obtained not only in single protein adsorption system but also in the competitive adsorption system of several proteins and BHb, that is, the imprinted space was reserved for BHb even if other proteins coexisted, although their nonspecific adsorption on non-imprinted surface was not avoided. 相似文献
516.
Keisuke Ohtani Philipp Gubler Makoto Oka 《The European Physical Journal A - Hadrons and Nuclei》2011,47(9):114
QCD sum rules of the nucleon channel are reanalyzed, using the maximum-entropy method (MEM). This new approach, based on the
Bayesian probability theory, does not restrict the spectral function to the usual “pole + continuum” form, allowing a more
flexible investigation of the nucleon spectral function. Making use of this flexibility, we are able to investigate the spectral
functions of various interpolating fields, finding that the nucleon ground state mainly couples to an operator containing
a scalar diquark. Moreover, we formulate the Gaussian sum rule for the nucleon channel and find that it is more suitable for
the MEM analysis to extract the nucleon pole in the region of its experimental value, while the Borel sum rule does not contain
enough information to clearly separate the nucleon pole from the continuum. 相似文献
517.
A. A. Kaminskii H. Rhee H. J. Eichler K. Ueda K. Oka H. Shibata 《Applied physics. B, Lasers and optics》2008,93(4):865-872
We report the experimental investigations of nonlinear-laser effects in LuVO4 vanadate under one-micron picosecond Nd3+:Y3Al5O12 pumping. In this tetragonal host-crystal for Ln3+ lasants for the first time we excited ultra-broad, more than one and half octave (13500 cm−1) Raman induced Stokes and anti-Stokes generation combs and observed multi-step cascaded parametric χ
(3)-lasing in UV spectral region. All generation lines were identified and attributed to SRS-promoting modes of the crystal (ω
SRS1≈900 cm−1 and ω
SRS2≈113 cm−1). We classified this vanadate as a promising material for self-Raman laser converters. 相似文献
518.
A Mueller matrix polarimeter acquired for four-channeled spectra is proposed. Both the polarizing and analyzing optics of this system consist of a linear polarizer and a high-order retarder. The polarizing elements can modulate the polarization states in the wavenumber space. By applying a Fourier transform method to a single-channeled spectrum, nine elements of the Mueller matrix can be deconvoluted without modifying the configuration of either the polarizing or analyzing optics. It is thus possible to determine the wavelength dependence of all the Mueller matrix elements from four-channeled spectra obtained using four different configurations for the polarizing and analyzing optics. The performance of this method is evaluated by measuring polarization properties, such as retardance, azimuthal angle, and linear diattenuation, from the obtained Mueller matrix in wavenumber space. 相似文献
519.
520.
Photoinduced electron‐transfer reactions of tris(2,2′‐bipyridine)ruthenium(II)‐based carbonic anhydrase inhibitors tethering plural binding sites 下载免费PDF全文
Mikiko Suwa Narumi Imamura Pirika Awano Eiji Nakata Hiroshi Takashima 《Journal of Physical Organic Chemistry》2018,31(9)
Tris(2,2′‐bipyridine)ruthenium(II) complex‐based carbonic anhydrase (CA) inhibitors, [Ru(bpy)2(bpydbs)]2+ {bpy = 2,2′‐bipyridine and bpydbs = 2,2′‐bipyridinyl‐4,4′‐dicarboxilic acid bis[(2‐{2‐[2‐(4‐sulfamoylbenzoylamino)ethoxy]ethoxy}ethyl)amide]} and [Ru(bpydbs)3]2+, tethering plural benzenesulfonamide groups have been prepared. The CA catalytic activity was effectively suppressed by these synthetic [Ru(bpy)2(bpydbs)]2+ and [Ru(bpydbs)3]2+ inhibitors, and their dissociation constants at pH = 7.2 and at 25°C were determined to be KI = 0.93 ± 0.02 μM and KI = 0.24 ± 0.03 μM, respectively. Next, 2 photoinduced electron‐transfer (ET) systems comprising a Ru2+‐CA complex and an electron acceptor, such as chloropentaamminecobalt(III) ([CoCl(NH3)5]2+) or methylviologen (MV2+) were studied. In the presence of CA and a sacrificial electron acceptor, such as pentaamminechlorocobalt(III) complex, the photoexcited triplet state of 3([Ru(II)]2+)* was quenched through an intermolecular photoinduced ET mechanism. In case of the [Ru(bpydbs)3]2+‐CA‐MV2+ system, the photoexcited triplet state of 3([Ru(bpydbs)3]2+)* was quenched by sacrificial quencher through an intermolecular photoinduced ET mechanism, giving the oxidized [Ru(bpydbs)3]3+. Then the following intramolecular ET from the amino acid residue, Tyr6, near the active site of CA proceeded. We observed a transient absorption around at 410 nm, arising from the formation of a Tyr?+ in the [Ru(bpydbs)3]2+‐CA‐MV2+ system. These artificial Ru(II)‐CA systems may clearly demonstrate both intermolecular and intramolecular photoinduced ET reactions of protein and could be one of the interesting models of the ET proteins. Their photophysical properties and the detailed ET mechanisms are discussed in order to clarify the multistep ET reactions. 相似文献