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排序方式: 共有535条查询结果,搜索用时 15 毫秒
31.
Atsunori Ono Yohei Takahashi Sumio Kato Masataka Ogasawara Takashi Wakabayashi Yuunosuke Nakahara Shinichi Nakata 《Research on Chemical Intermediates》2011,37(9):1225-1230
A10(PO4)6(OH)2 (A = Ca and Sr)-supported Pt catalysts were prepared and their catalytic activity in NO reduction were investigated. The Sr10(PO4)6(OH)2-supported catalyst had high catalytic activity in the C3H6?CNO?CO2 reaction; the activity was higher than that of the ??-Al2O3-supported catalyst at 300 °C. The basicity of the apatite supports would affect the chemical state of Pt on catalyst, resulting in promotion of NO reduction. 相似文献
32.
Adsorption and photochemical behaviors of the novel cationic xanthene derivative on the clay surface
Yuta Ohtani Yohei Ishida Yuka Ando Hiroshi Tachibana Tetsuya Shimada Shinsuke Takagi 《Tetrahedron letters》2014
Novel tetra-cationic xanthene derivative (Flu) was synthesized. Its adsorption and photochemical behaviors on the clay surface were investigated. Fluorescence quantum yield (?f) and fluorescence lifetime were 0.50 and 2.9 ns for Flu/clay complex. ?f of Flu was enough high (>0.1) even at high density conditions (0.080 molecules nm−2). It is supposed that the strong interaction between clay and Flu by the ‘Size-Matching Effect’ realizes the highly emissive clay complexes at high density adsorption condition by a suppression of a molecular aggregation, which tends to decrease the photochemical activity. 相似文献
33.
Yohei Morinishi 《Journal of computational physics》2010,229(2):276-300
The form of convective terms for compressible flow equations is discussed in the same way as for an incompressible one by Morinishi et al. [Y. Morinishi, T.S. Lund, O.V. Vasilyev, P. Moin, Fully conservative higher order finite difference schemes for incompressible flow, J. Comput. Phys. 124 (1998) 90], and fully conservative finite difference schemes suitable for shock-free unsteady compressible flow simulations are proposed. Commutable divergence, advective, and skew-symmetric forms of convective terms are defined by including the temporal derivative term for compressible flow. These forms are analytically equivalent if the continuity is satisfied, and the skew-symmetric form is secondary conservative without the aid of the continuity, while the divergence form is primary conservative. The relations between the present and existing quasi-skew-symmetric forms are also revealed. Commutable fully discrete finite difference schemes of convection are then derived in a staggered grid system, and they are fully conservative provided that the corresponding discrete continuity is satisfied. In addition, a semi-discrete convection scheme suitable for compact finite difference is presented based on the skew-symmetric form. The conservation properties of the present schemes are demonstrated numerically in a three-dimensional periodic inviscid flow. The proposed fully discrete fully conservative second-order accurate scheme is also used to perform the DNS of compressible isotropic turbulence and the simulation of open cavity flow. 相似文献
34.
Feroza Begum Yoshinori Namihira S. M. Abdur Razzak Shubi F. Kaijage Nguyen H. Hai Kazuya Miyagi Hiroki Higa Nianyu Zou 《Optical Review》2009,16(2):54-58
This research presents a simple index-guiding square photonic crystal fibers (SPCFs) that has a silica core surrounded by
air hole with two different diameters. It is demonstrated that the designed two-different-size hole-arrayed index-guiding
SPCFs has a ultra-flattened chromatic dispersion of 0 ± 0.9 ps/(nm·km) in a wavelength range of 1.34 to 1.61 μm and low confinement
loss of less than 10−7 dB/m in a wavelength range of 1.2 to 1.7 μm. It has also been shown that the proposed SPCFs show reasonable dispersion tolerance. 相似文献
35.
The relationship among the Wigner crystal, charge ordering, and the Mott insulator is studied by the path-integral renormalization group method in two-dimensional systems with long-range Coulomb interaction. In contrast to the insensitivity of the Hartree-Fock results, the stability of the solid drastically decreases with the decrease in the lattice commensurability. The transition to liquid occurs at the electron gas parameter r(s) approximately 2 for the filling n=1/2, showing a large reduction from r(s) approximately 35 in the continuum limit. A correct account of quantum fluctuations is crucial to understanding the charge-order stability generally observed only at simple fractional fillings and the nature of quantum liquids away from them. 相似文献
36.
Optical constants of polymer coatings in the infrared 总被引:1,自引:0,他引:1
The refractive indices and absorption coefficients of fluorocarbon, polymethyl methacrylate, and polyimide were measured in the wavelength range of 2–12 μm. The reflection losses of KRS-5 and CsI windows were reduced successfully by coating fluorocarbon polymers on the surfaces. 相似文献
37.
A simple Raman probe was realized using a single flexible hollow waveguide (HW). A HW coated with a silver film, which had reasonable transmission and little optical background noise, was used as a bidirectional transmission fiber for both the excitation and collection of Raman scattered light. The HW itself generated no Raman scattering or fluorescence noise during transmission. A complex filtering system at the end of the waveguide was thus unnecessary. In addition, the measured Raman spectra showed better signal-to-noise ratios than a conventional Raman fiber probe. The HW's suitability as a Raman fiber probe was also demonstrated. 相似文献
38.
The cationic ruthenium catalyst (Cp*RuCl2)2/AgOTf/Ligand promotes the addition reaction of carboxylic acids across olefins without beta-hydride elimination. 相似文献
39.
Anderson GS Tsujino I Miyagi K Sampson R Sieber F 《Journal of photochemistry and photobiology. B, Biology》2003,69(2):87-95
Paediatric solid tumours exhibit steep dose-response curves to alkylating agents and are therefore considered candidates for high-dose chemotherapy and autologous stem cell support. There is growing evidence that autologous stem cell grafts from patients with solid tumours are frequently contaminated with live tumour cells. The objective of this study was to perform, in a preclinical purging model, an initial assessment of the safety and efficacy of a two-step purging procedure that combined Merocyanine 540-mediated photodynamic therapy (MC540-PDT) with a brief exposure to the alkyl-lysophospholipid, Edelfosine. Human and murine bone marrow cells and Neuro-2a murine neuroblastoma, SK-N-SH human neuroblastoma, SK-ES-1 and U-2 OS human osteosarcoma, G-401 and SK-NEP-1 human Wilms' tumour, and A-204 human rhabdomyosarcoma cells were exposed to a fixed dose of MC540-PDT followed by a brief incubation with graded concentrations of Edelfosine. Survival was subsequently assessed by in vitro clonal assay or, in the case of CD34-positive haematopoietic stem cells, by an immunohistochemical method. Combination purging with MC540-PDT and Edelfosine depleted all tumour cells by >4 log while preserving at least 15% of murine granulocyte/macrophage progenitors (CFU-GM), 34% of human CFU-GM, and 31% of human CD34-positive cells. The data suggest that combination purging with MC540-PDT and Edelfosine may be useful for the ex vivo purging of autologous stem cell grafts from patients with paediatric solid tumours. 相似文献
40.
S. M. Abdur Razzak Yoshinori Namihira Kazuya Miyagi Feroza Begum Shubi Kaijage Nguyen Hoang Hai Tatsuya Kinjo Nianyu Zou 《Optical Review》2007,14(1):14-16
This paper presents a novel technique for the control of chromatic dispersion and confinement loss in hexagonal photonic crystal
fibers (H-PCFs). It is demonstrated that it is possible to obtain very low chromatic dispersion of 0 ± 0:38 ps/(nm·km) in
the wavelength range of 1.41 to 1.66 μm and confinement loss of less than 0.0001 dB/km from a six ring modified H-PCF (MH-PCF).
The higher order dispersion at 1.55 μm is about −0.001 ps/(nm2-km). 相似文献