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71.
T. Sakai 《Physica C: Superconductivity and its Applications》2008,468(15-20):1163-1165
Using the numerical diagonalization of the finite-cluster t–J model, we investigate the mechanism of the charge stripes based on the ring exchange interaction. We calculate the many-hole correlation functions related with the two-types of charge stripes; the vertical and diagonal types of the charge stripe. As a result, we present a phase diagram including the two stripe phases and a phase separation phase. 相似文献
72.
Senoy Thomas D. Sakthikumar Yasuhiko Yoshida M. R. Anantharaman 《Journal of nanoparticle research》2008,10(1):203-206
Sol–gel glasses with Fe3O4 nanoparticles having particle sizes laying in the range 10–20 nm were encapsulated in the porous network of silica resulting
in nanocomposites having both optical and magnetic properties. Spectroscopic and photoluminescence studies indicated that
Fe3O4 nanocrystals are embedded in the silica matrix with no strong Si–O–Fe bonding. The composites exhibited a blue luminescence.
The optical absorption edge of the composites red shifted with increasing concentration of Fe3O4 in the silica matrix. There is no obvious shift in the position of the luminescence peak with the concentration of Fe3O4 except that the intensity of the peak is decreased. The unique combinations of magnetic and optical properties are appealing
for magneto–optical applications. 相似文献
73.
A. K. Kurilkin T. Saito V. P. Ladygin T. Uesaka T. A. Vasiliev M. Janek M. Hatano A. Yu. Isupov H. Kato N. B. Ladygina Y. Maeda A. I. Malakhov J. Nishikawa T. Ohnishi H. Okamura S. G. Reznikov H. Sakai N. Sakamoto S. Sakoda Y. Satou K. Sekiguchi K. Suda A. Tamii N. Uchigashima K. Yako 《The European physical journal. Special topics》2008,162(1):133-136
The data on the vector A
y
and tensor A
yy
, A
xx
, A
xz
analyzing powers for the
d → 3H p reaction have been obtained at the energy of the initial deuteron of 200MeV in the angular range of 0–95 degrees in the c.m.s.
The calculations performed within one-nucleon exchange model with the use of the standard three-nucleon bound state wave functions
fail to reproduce the data on the tensor analyzing powers. 相似文献
74.
Takashi Uchida Masaya Tazawa Hiroshi Sakai Yoshihiro Kobayashi 《Applied Surface Science》2008,254(23):7591-7595
Radial breathing modes (RBMs) in resonance Raman spectra from single-walled carbon nanotubes (SWCNTs) on a SiO2/Si (0 0 1) substrate are studied between 25 and 720 °C. A change in the relative intensity of each RBM peak with temperature is observed, which originates from the temperature dependence of the resonance condition of nanotubes. For 25 °C, each RBM peak is reasonably assigned on the basis of data in the literature [J. Maultzsch, H. Telg, S. Reich, F. Hennrich, C. Thomsen, Phys. Rev. B 72 (2005) 205438]. By taking into account the temperature-dependent behavior of the relative intensity of the RBM peaks, each RBM peak is successfully assigned even for 720 °C. It is found that most of the observed RBM peaks for a laser excitation energy of Eexc = 1.96 eV are from chiral SWCNTs. These results make it possible to discuss further details of the chirality-dependent growth behavior observed for in situ Raman spectroscopy. 相似文献
75.
Dr. Yohei Ogiwara Yurika Iino Prof. Dr. Norio Sakai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(26):6513-6516
A method for the palladium/copper-catalyzed direct acylation of azoles with acyl fluorides is described. This study reports the first examples of acyl fluorides being used as acylation reagents in transition-metal-catalyzed aromatic C−H bond functionalization reactions. Depending on the reaction temperature, decarbonylative coupling may also occur. Mechanistic studies suggest that the cleavage of the aromatic C−H bond, promoted by a copper-phosphine species, is not the rate-limiting step of this acylation. 相似文献
76.
77.
Heorhii V. Humeniuk Giuseppe Licari Eric Vauthey Naomi Sakai 《Supramolecular chemistry》2020,32(2):106-111
ABSTRACTDesign, synthesis and evaluation of push-pull N,N′-diphenyl-dihydrodibenzo[a,c]phenazines are reported. Consistent with theoretical predictions, donors and acceptors attached to the bent mechanophore are shown to shift absorption maxima to either red or blue, depending on their positioning in the chromophore. Redshifted excitation of push-pull fluorophores is reflected in redshifted emission of both bent and planar excited states. The intensity ratios of the dual emission in more and less polar solvents imply that excited-state (ES) planarization decelerates with increasing fluorophore macrodipole, presumably due to attraction between the wings of closed papillons. ES planarization of highly polarisable papillons is not observed in lipid bilayer membranes. All push-pull papillon amphiphiles excel with aggregation-induced emission (AIE) from bent ES as micelles in water and mechanosensitivity in viscous solvents. They are not solvatochromic and only weakly fluorescent (QY < 4%). 相似文献
78.
Yasuhiko Syono Atsuko Ito Setsu Morimoto 《Journal of Physics and Chemistry of Solids》1981,42(6):483-486
The Mössbauer spectra of ilmenite (FeTiO3), Fe2+-doped ilmenites, MTiO3 (M = Cd, Mn, Zn, Co, Mg and Ni) and MGeO3 (M = Mn, Zn and Mg), have been studied from 4.2 K to room temperature. Systematic variations in the isomer shift and quadrupole splitting at room temperature are correlated with the change in ionic radii of the host M ions and the c/a ratio of the host crystal, respectively. The quadrupole splittings show a remarkable temperature variation; the magnetic ilmenites show either a sudden increase or a sudden decrease of quadrupole splittings below the Néel temperature, depending on the orientation of the spin axis with respect to the c axis. 相似文献
79.
The electrospray droplet impact (EDI) was applied to bradykinin, polyethylene terephthalate (PET), SiO2/Si, and indium phosphide (InP). It was found that bradykinin deposited on the stainless steel substrate was ionized/desorbed without the accumulation of radiation products. The film thickness desorbed by a single collisional event was found to be less than 10 monolayers. In the EDI mass spectra for PET, several fragment ions were observed but the XPS spectra did not change with prolonged cluster irradiation. The etching rate for SiO2 by EDI was measured to be ∼0.2 nm/min. The surface roughness of InP etched by EDI was found to be one order of magnitude smaller than that etched by 3 keV Ar+ for about the same etching depths. EDI is capable of shallow surface etching with little damage left on the etched surface. 相似文献
80.
Effects of relaxation of occupied band electrons to the ?-hole state through the hybridization between ? and band states are studied based on a detailed model for Ce-monopnictides. The effective 4? level is shifted about 1–2 eV to shallow energy side from the unrenormalized bare level in processes in which the 4? electron is only virtually excited, such as in excitation to the vacant p band states through the p-? mixing. Photoemission spectra show two peaks, one near the Fermi energy and the other about 3 eV below it. The latter is shifted to deep energy side about 0.5–1 eV from the bare level when it lies near the bottom of the valence band. The discrepancy between the 4? level estimated from the low energy phenomena and that from photoemission is resolved. 相似文献