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1.
Niizeki K 《Physical review letters》2004,93(4):045501
A classification of icosahedral quasicrystals based the mutual-local-derivability (MLD) concept is performed. There are eighteen MLD classes within the reservation that the faces of the hyperatoms (windows) are perpendicular to the two-, three-, or fivefold axes. Each MLD class has a representative member to be called the Bravais quasilattice from which the structure of each member of the class is derived by decorating it according to a local rule depending on the member. 相似文献
2.
One-dimensional quasilattices, namely, the geometrical objects that represent quasicrystals, are classified into mutual local-derivability (MLD) classes. Besides the familiar class, there exist an infinite number of new MLD classes, and different MLD classes are distinguished by the inflation rules of their representatives. It has been found that electronic properties of a new MLD class are characterized by the presence of marginal critical states, which are considered to be nearly localized states. 相似文献
3.
Satoru Amou Kazuhiko Takeuchi Michihiko Asai Kouichi Niizeki Takashi Okada Makoto Seino Osamu Haba Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》1999,37(19):3702-3709
Regiocontrolled polymer (2) having 2-naphthol unit was prepared by oxidative coupling polymerization of bis(2-naphthol) (1). Polymerizations were conducted in dichloromethane in the presence of [di-μ-hydroxo-bis(N,N,N′,N′-tetramethylethylenediamine)copper(II)] chloride [CuCl(OH)TMEDA] under air at room temperature, producing polymers with number-average molecular weights up to 12,000. The structure of polymer 2 was characterized by 270 MHz 1H–NMR and 68.5 MHz 13C–NMR spectroscopies and was estimated to consist almost completely of 1,1′-linkage. The polymer was readily soluble in polar aprotic solvents and tetrahydrofuran at room temperature. Thermogravimetric analysis of polymer 2 showed 10% weight loss at 450°C in nitrogen. The model reactions were studied to clarify the applicability of CuCl(OH)TMEDA for coupling of naphthol derivatives. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3702–3709, 1999 相似文献
4.
Y. Shimazu Y. Wada T. Niizeki Y. Yamamoto T. Yoshida Z. Wada T. Yokoyama 《Physica E: Low-dimensional Systems and Nanostructures》2005,29(3-4):679
We measured magnetic flux produced by coupled flux qubits with a switching current measurement of a DC-SQUID. Both the circulating currents and the SQUID–qubit coupling were designed to be asymmetric. The experimental result exhibits a broad peak and dip, and does not agree with the thermally averaged magnetic flux calculated with the two qubit Hamiltonian. This disagreement can be explained in terms of nonthermal excitation of the coupled qubits, which is probably caused by the microwaves generated by the DC-SQUID in the voltage state. 相似文献
5.
Spin dependent quantum well resonance has been investigated in fully epitaxial magnetic tunnel junctions with Fe(001)/MgO(001)/ultrathin Fe(001)/Cr(001) structure. The dI/dV spectra clearly show the resonant peaks which shift systematically depending on the thickness of an ultrathin electrode as predicted in ab initio calculation [Zhong-Yi Lu et al, Phys. Rev. Lett. 94, 207210 (2005)]. The magnetotransport is strongly modulated at the same bias voltage as the resonant peaks. This control of the magnetotransport in magnetic tunnel junctions at a specific bias voltage will contribute to the development of active spintronic devices. 相似文献
6.
Donaire A Jiménez B Fernández CO Pierattelli R Niizeki T Moratal JM Hall JF Kohzuma T Hasnain SS Vila AJ 《Journal of the American Chemical Society》2002,124(46):13698-13708
The blue copper proteins (BCPs), pseudoazurin from Achromobacter cycloclastes and rusticyanin from Thiobacillus ferrooxidans, have been investigated by (1)H NMR at a magnetic field of 18.8 T. Hyperfine shifts of the protons belonging to the coordinated ligands have been identified by exchange spectroscopy, including the indirect detection for those resonances that cannot be directly observed (the beta-CH(2) of the Cys ligand, and the NH amide hydrogen bonded to the S(gamma)(Cys) atom). These data reveal that the Cu(II)-Cys interaction in pseudoazurin and rusticyanin is weakened compared to that in classic blue sites (plastocyanin and azurin). This weakening is not induced by a stronger interaction with the axial ligand, as found in stellacyanin, but might be determined by the protein folding around the metal site. The average chemical shift of the beta-CH(2) Cys ligand in all BCPs can be correlated to geometric factors of the metal site (the Cu-S(gamma)(Cys) distance and the angle between the CuN(His)N(His) plane and the Cu-S(gamma)(Cys) vector). It is concluded that the degree of tetragonal distortion is not necessarily related to the strength of the Cu(II)-S(gamma)(Cys) bond. The copper-His interaction is similar in all BCPs, even for the solvent-exposed His ligand. It is proposed that the copper xy magnetic axes in blue sites are determined by subtle geometrical differences, particularly the orientation of the His ligands. Finally, the observed chemical shifts for beta-CH(2) Cys and Ser NH protons in rusticyanin suggest that a less negative charge at the sulfur atom could contribute to the high redox potential (680 mV) of this protein. 相似文献
7.
Tanaka Noriyuki Nishidate Izumi Nakano Kazuya Aizu Yoshihisa Niizeki Kyuichi 《Optical Review》2016,23(2):323-331
Optical Review - We investigated a method to evaluate the arterial inflow and the venous capacitance in the skin tissue of streptozotocin-induced type 1 diabetic rats from RGB digital color images.... 相似文献
8.
Ichihara T Ishihara M Ohnuma H Niizeki T Satou Y Okamura H Kubono S Tanaka MH Fuchi Y 《Physical review letters》2002,89(14):142501
The charge-exchange reaction 60Ni(13C,13N)60Co at E/A=100 MeV has been studied to locate isovector (deltaT=1) non-spin-flip (deltaS=0) giant resonances. Besides the giant dipole resonance at E(x)=8.7 MeV, another resonance has been observed at E(x)=20 MeV with a width of 9 MeV. Distorted-wave Born approximation analysis on the angular distribution clearly indicated the L=2 multipolarity, attributing the E(x)=20 MeV state to the giant isovector quadrupole resonance. 相似文献
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10.
Komajiro Niizeki 《Solid State Communications》1973,12(4):267-270
The single site coherent-potential approximation (SCPA) is generalized in order to treat effects due to clusterization of scatterers, off-diagonal disorder, crystal field and/or short range order. Present formalism is a straightforward generalization of Soven's original method i.e. the multiple scattering formalism by which he derived the SCPA. 相似文献