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101.
Xue QZ Xue QK Kuwano S Sadowski JT Kelly KF Sakurai T Ohno T 《Physical review letters》2000,84(17):4015
102.
Masami Kumagai Akihito Taguchi Toshihide Takagahara Takahisa Ohno Kousuke Yakubo 《Solid State Communications》2008,145(3):154-158
The exciton properties of thin nanotube structures are investigated theoretically. Anisotropic size dependencies have been found in the exciton binding energy, the kinetic energy for the relative motions of an electron and a hole, and the wavefunction. These anisotropies arise from the different boundary conditions in the tube-length and circumferential directions, namely, the topological features of nanotubes. We also found that it is possible to change the topology of exciton wavefunctions by varying the tube-length and the tube-radius. These findings suggest that the optical properties of nanotubes such as oscillator strength or nonlinear susceptibilities can be controlled by tuning the structural parameters, thus yielding a novel guiding principle for designing optical functional materials. 相似文献
103.
Keiji Izuchi Shû ichi Ohno 《Proceedings of the American Mathematical Society》2006,134(5):1359-1364
We study Hankel-type operators on the space of bounded harmonic functions on the open unit disk. These operators are related to tight uniform algebras, the Dunford-Pettis property, and Bourgain algebras.
104.
Kitano H Kondo T Kamada T Iwanaga S Nakamura M Ohno K 《Colloids and surfaces. B, Biointerfaces》2011,88(1):455-462
An amphoteric copolymer brush of methacrylic acid (MA) and 2-(dimethylamino)ethyl methacrylate (DMAEMA) was prepared by reversible addition-fragmentation chain-transfer (RAFT) polymerization using both a free chain transfer agent (n-butylsulfanylthiocarbonylsulfanyl-2-methyl propionic acid) and a radical initiator (4,4'-azobis(4-cyanopentanoic acid)) covalently fixed to a glass substrate. An aqueous solution of the copolymer, Poly(MA-r-DMAEMA), which was simultaneously obtained in liquid phase, had a sufficiently small polydispersity in its molecular weight. The copolymer brush showed effective suppression of non-specific adsorption of bovine serum albumin and egg white lysozyme to the brush. In contrast, both negatively charged PolyMA and positively charged PolyDMAEMA brushes significantly adsorbed the proteins irrespective of their net charges. Upon ion beam irradiation, furthermore, a hollow space with a designed shape could be made on the glass substrate, and both HEK293 and HepG2 cells non-specifically adhered to the space, forming aggregates, while no adhesion to the non-treated area on the brush was observed. These results suggest that the amphoteric polymer brushes will be useful materials for biomedical applications. 相似文献
105.
Time-resolved fluorescence spectroscopy was used to characterize water-soluble organic matter (WSOM) which plays an important
role in soil ecosystem processes. WSOM was extracted from plant biomass, animal manures, and soils from controlled cropping
systems studies with known histories of organic amendments. Lifetime constants were derived using the multi-way PowerSlicing
method which provides a non-iterative, multi-exponential fitting of decay profiles. The lifetimes obtained by PowerSlicing
were not significantly different from those obtained using the traditional discrete components analysis. The three components
attributed to WSOM had lifetimes of 0.38 ± 0.14, 2.11 ± 0.72, and 7.08 ± 1.18 ns which are in agreement with previous lifetimes
reported for humic substances. This study provides further support for the new paradigm for the structure of soil organic
matter where the organic matter is composed of low-molecular-weight components held together by hydrogen bonding and hydrophobic
interactions. 相似文献
106.
Yuasa J Ohno T Miyata K Tsumatori H Hasegawa Y Kawai T 《Journal of the American Chemical Society》2011,133(25):9892-9902
Highly luminescent tris[β-diketonate (HFA, 1,1,1,5,5,5-hexafluoropentane-2,4-dione)] europium(III) complexes containing a chiral bis(oxazolinyl) pyridine (pybox) ligand--[(Eu(III)(R)-Ph-pybox)(HFA)(3)], [(Eu(III)(R)-i-Pr-pybox)(HFA)(3)], and [(Eu(III)(R)-Me-Ph-pybox)(HFA)(3)])--exhibit strong circularly polarized luminescence (CPL) at the magnetic-dipole ((5)D(0) → (7)F(1)) transition, where the [(Eu(III)(R)-Ph-pybox)(HFA)(3)] complexes show virtually opposite CPL spectra as compared to those with the same chirality of [(Eu(III)(R)-i-Pr-pybox)(HFA)(3)] and [(Eu(III)(R)-Me-Ph-pybox)(HFA)(3)]. Similarly, the [(Tb(III)(R)-Ph-pybox)(HFA)(3)] complexes were found to exhibit CPL signals almost opposite to those of [(Tb(III)(R)-i-Pr-pybox)(HFA)(3)] and [(Tb(III)(R)-Me-Ph-pybox)(HFA)(3)] complexes with the same pybox chirality. Single-crystal X-ray structural analysis revealed ligand-ligand interactions between the pybox ligand and the HFA ligand in each lanthanide(III) complex: π-π stacking interactions in the Eu(III) and Tb(III) complexes with the Ph-pybox ligand, CH/F interactions in those with the i-Pr-pybox ligand, and CH/π interactions in those with the Me-Ph-pybox ligand. The ligand-ligand interactions between the achiral HFA ligands and the chiral pybox results in an asymmetric arrangement of three HFA ligands around the metal center. The metal center geometry varies depending on the types of ligand-ligand interaction. 相似文献
107.
Hiroshi Kashiwagi Toshikazu Takada Shigeru Obara Eisaku Miyoshi Kimio Ohno 《International journal of quantum chemistry》1978,14(1):13-27
Ab initio LCAO SCF MO calculations are carried out on planar Co-porphine with a basis set of roughly double zeta quality for Co and N and of single zeta quality for C and H. The net charge on Co and N and the overlap population between them are 1.78, ?0.57, and 0.06, respectively, in the 2A1g, state, which is known to be the ground state by experiment. The bonding in this complex is thus largely ionic. The first and second calculated ionization potentials are 6.51 and 6.77 eV, respectively, and are in reasonable agreement with the observed ionization potentials of 6.44 and 6.62 eV for Ni-tetraphenylporphine. CI calculations within the framework of the ligand field theory are also performed. The calculated order of the five lowest states is 4B2g ≈ 4Eg, 4A2g, 2A1g, 4Eg from below and is not in agreement with the semiempirical order of 2A1g ≈ 4B2G, 4A2g, 2Eg, 4Eg determined by Lin. 相似文献
108.
K. Ohno Y. Noguchi S. Ueda J. Onoe 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,43(1-3):137-140
Optimized three-dimensional (3D) cell structures and energy bands
of fused (peanut-shaped) C60 polymers (p55 and p66) have been
investigated using the first-principles pseudopotential approach
within the local density approximation of the density functional theory.
We found that the resulting electronic structure is either metal or
semiconductor depending on the shape of the polymer chains and
the unit cell structure. 相似文献
109.
A. Kakuta M. Kuramoto M. Ohno H. Kushida A. Tanioka K. Ishikawa 《Journal of polymer science. Part A, Polymer chemistry》1980,18(11):3229-3243
A freeze-dried cellulose acetate membrane fine structure was observed with an ultrathin sectioning electron microscope. The fine structure for the top surface in this membrane could be seen by lead citrate staining ultrathin sectioning. This network structure was observed among pores, which existed in porous substrate. The pore diameter in the top surface was about 50 Å, a value that agrees approximately with the value estimated by gas permeation. 相似文献
110.
Takashi Tsuno Yu Sugiyama Henri Brunner Michael Bodensteiner Kosei Lee 《Journal of Coordination Chemistry》2017,70(20):3459-3470
Treatment of NiCl2 with the tripod ligand (LMent,SC)-1H led to (LMent,SC)-[Cp(PNMent)NiCl] in which the potentially tridentate ligand coordinated to the metal center in a bidentate way via the cyclopentadienyl system and the phosphorus atom. In the presence of NH4PF6 [(LMent,SC)-[Cp(PNMent)NiCl] readily underwent Cl/PPh3 exchange to give (LMent,SC)-[Cp(PNMent)NiPPh3]PF6. Reaction of (LMent,SC)-[Cp(PNMent)NiCl] with 0.5 eq. of dppe afforded [{(LMent,SC)-[Cp(PNMent)Ni]}2dppe](PF6)2. (LMent,SC)-[Cp(PNMent)NiPPh3]PF6 and [{(LMent,SC)-[Cp(PNMent)Ni]}2dppe](PF6)2 were characterized by NMR and MS spectroscopy, and also by single crystal X-ray diffraction. The cyclopentadienyl ligand of (LMent,SC)-[Cp(PNMent)NiPPh3]PF6 shows a distortion intermediate between the ene-allyl and diene types, while the two cyclopentadienyl ligands of [{(LMent,SC)-[Cp(PNMent)Ni]}2dppe](PF6)2 have intermediate and diene distortions, respectively. According to the temperature dependent NMR spectra of (LMent,SC)-[Cp(PNMent)NiPPh3]PF6 and [{(LMent,SC)-[Cp(PNMent)Ni]}2dppe](PF6)2 two different conformations of the tether in the Cp(PNMent)Ni system could be frozen out at low temperatures. 相似文献