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排序方式: 共有1359条查询结果,搜索用时 31 毫秒
961.
Hosokoshi Y Katoh K Nakazawa Y Nakano H Inoue K 《Journal of the American Chemical Society》2001,123(32):7921-7922
962.
Yamana K Zako H Asazuma K Iwase R Nakano H Murakami A 《Angewandte Chemie (International ed. in English)》2001,40(6):1104-1106
963.
The quasi-degenerate perturbation theory (QDPT) with complete active space (CAS) self-consistent field (SCF) reference functions is extended to the general multiconfiguration (MC) SCF references functions case. A computational scheme that utilizes both diagrammatic and sum-over-states approaches is presented. The second-order effective Hamiltonian is computed for the external intermediate configurations (including virtual or/and core orbitals) by the diagrammatic approach and for internal intermediate configurations (including only active orbitals) by the configuration interaction matrix-based sum-over-states approach. The method is tested on the calculations of excitation energies of H(2)O, potential energy curves of LiF, and valence excitation energies of H(2)CO. The results show that the present method yields very close results to the corresponding CAS-SCF reference QDPT results and the available experimental values. The deviations from CAS-SCF reference QDPT values are less than 0.1 eV on the average for the excitation energies of H(2)O and less than 1 kcal/mol for the potential energy curves of LiF. In the calculation of the valence excited energies of H(2)CO, the maximum deviation from available experimental values is 0.28 eV. 相似文献
964.
Isao Tanaka Youji InoueKatsu Tanaka Yoshitaka IzumiShinji Okamoto Mitsuhiro KawanishiNoboru Miura Hironaga MatsumotoRyotaro Nakano 《Journal of luminescence》2002,96(1):69-74
We characterized the crystallization and luminescence of blue-emitting BaAl2S4 : Eu electroluminescent thin films, prepared using switching electron-beam evaporation with two targets. From the photoluminescence intensity and decay profile of the activated Eu2+ ions in the BaAl2S4 : Eu, we found that the optimum annealing conditions for preparing highly luminescent thin films are a temperature of around 900°C and an annealing time of 2 min. We analyzed the crystalline properties using cross-sectional transmission electron microscope images. Evaluation of the cathodoluminescence spectra in the cross-sections showed that the BaAl2S4 : Eu emitting layer was luminously inhomogeneous on the depth of the layer and that the main luminescent area was near the surface of the emitting layer. We discuss here the relationship between the crystalline and luminescent properties. 相似文献
965.
Fumitoshi Yamashita Kiyomi Kawamura Yukihiro Okada Hiroshi Murakami Masaki Ogushi Masaki Nakano Hirotoshi Fukunaga 《Journal of magnetism and magnetic materials》2007
When a radially anisotropic rare earth bonded magnet for a rotor with a high (BH)max value is magnetized multi-polarly, its flux distributes rectangularly and increases a cogging torque. In order to overcome this difficulty, we newly developed highly dense Sm2Fe17N3 and Nd2Fe14B-based composite bonded magnets with continuously controlled anisotropy directions by using a viscous deformation technique. 相似文献
966.
We have succesfully investigated emissive interface states in fabricated indium‐tin‐oxide (ITO)/N,N′‐di‐1‐naphthyl‐N,N′‐diphenyl‐1,1′‐biphenyl‐4,4′diamine (α‐NPD)/tris(8‐hydroxyquinoline) aluminum (Alq3)/LiF/Al organic light‐emitting diodes (OLEDs) by a modified deep‐level optical spectroscopy (DLOS) technique. In the vicinity of the α‐NPD/Alq3 emissive interface, a discrete trap level was found to be located at ~1.77 eV below the conduction band of Alq3, in addition to band‐to‐band transitions of carriers from α‐NPD to Alq3. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
967.
M. Nakano H. Watanabe T. Shimizu N. Miyagawa S. Morita H. Katagiri H. Ishiguro 《Journal of Radioanalytical and Nuclear Chemistry》2000,243(2):319-322
The fire and explosion of the Bituminization Demonstration Facility at PNC Tokai Works were occurred on March 11th, 1997. As soon as the fire occurred, environmental monitoring was started. The influence of accidental release was recognized from some samples of airborne dust and surface soil on site. No influence was recognized from the samples off site except the airborne dust collected at O-arai (20 km south). The official statement by the Nuclear Safety Commission of Japan was: "It was less than the value which has an influence on the environment and health." 相似文献
968.
Yang Jung-Hoon Nakano Yoshikazu Murakami Yasunori Song Kwang-Soup Kawarada Hiroshi 《Journal of nanoparticle research》2008,10(1):69-76
Carbon nanotubes have been synthesized by catalytic chemical vapour deposition of acetylene diluted with argon using three
different catalysts, namely, nickel formate, cobalt formate and ferrocene. The synthesis was carried out at 700°C in a quartz
reactor for 30 minutes. Thermal analysis was carried out in order to determine the yield of the nanotube. It was found that
the deposit contains 86% nanotube, with nickel-based catalyst, which was the maximum. The yield of nanotube was 71 times that
of the nickel loading. The TEM images reveal helical type of nanotubes with iron catalyst while cobalt and nickel catalysts
yielded straight nanotubes. This technique can be explored for the bulk production of carbon nanotube in an economic way. 相似文献
969.
The purpose of this study is to understand the aerodynamic noise source distribution around a rotating fan blade by measuring
the noise signal and velocity field around the blade. The local noise-level distribution over the fan blade is measured by
microphone arrays, and the flow field is visualized by smoke and phase-averaged PIV measurement. The noise source distribution
is examined by cross-correlation analysis between noise signal and velocity fluctuation. It is found that the noise source
is located near the rotating fan blade, especially around leading and trailing edges. The separation and reattachment of flow
are observed near the leading edge, and the tip vortices and vortex shedding are found near the trailing edge. The cross-correlation
distribution of the noise signal and the radial velocity fluctuation shows large magnitude in the correlated regions, which
indicates the noise generation by the formation of vortex structure around the blade. 相似文献
970.
Methylene blue-sensitized photooxidation of N,N-disubstituted hydrazones gave various products , depending on the reaction temperature and N-substituents. The major reaction modes from the photo-oxidation of N,N-diphenylhydrazones were α-oxidation at room temperature and C=N cleavage at ?78 °C in contrast to C=N cleavage as an only reaction mode for the photooxidation of N,N-dimethylhydrazones at either room temperature or ?78 °C. 相似文献