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排序方式: 共有1325条查询结果,搜索用时 15 毫秒
61.
Mariana Fatobene Ando Sindy Fuhrmann Zhiwen Pan Bruno Poletto Rodrigues Tatsuya Mori Stefan G. Ebbinghaus Katrin Wondraczek Suguru Kitani Lothar Wondraczek 《Journal of the American Ceramic Society》2021,104(10):4991-5000
We use low-temperature heat capacity, low-frequency Raman scattering, and THz time domain spectroscopy in order to scale the vibrational density of states and the Boson peak in SiO2-Al2O3-B2O3 Yb-laser host glasses. When substituting B2O3 for SiO2 at constant Al2O3 dopant level, we find an optimal value for the ratio of B/Al in terms of mixture stability, at which the excess in the electron donor capability of Al2O3 (relative to the SiO2 backbone) is compensated by the more acidic B2O3. At this composition, Al2O3 plays a mediating role in the structure of aluminoborosilicate glasses, facilitating dissolution of Yb2O3 and admixture of B2O3 into the SiO2 network. 相似文献
62.
Juyong Jang Hidemasa Takana Yasutaka Ando Oleg P. Solonenko Hideya Nishiyama 《Journal of Thermal Spray Technology》2013,22(6):974-982
Carbon-doped titanium dioxide nanopowder has received much attention because of its higher photocatalytic performance, which is practically activated not only by UV, but also by visible light irradiation. In the present study, C-TiO2 nanopowder was synthesized by droplet injection of solution precursor in a DC-RF hybrid plasma flow system, resulting in higher photocatalytic performance even under visible light irradiation. In-flight C-TiO2 nanoparticles reacted with the high concentration of carbon in plasma flow and were then deposited on the surfaces of two quartz tubes in the upstream and downstream regions of this system. The collected C-TiO2 nanopowder contained anatase-rutile mixed-phase TiO2 and TiC, the contents of which depended on the location of the powder collection, the temperature, and the duration of plasma treatment. Highly functional C-TiO2 nanopowder collected in the downstream region exhibited a higher degradation rate of methylene blue than that of single-phase anatase TiO2, even under visible light irradiation, in spite of being TiC. 相似文献
63.
Summary Steel fibre reinforced metal matrix composites (FRM) consisting of high‐strength ductile steel wire and aluminium or titanium foil were fabricated by explosive bonding. The strength properties were evaluated by tensile tests. The optimum explosive loading (explosive mass/driver plate mass) increases with the volume fraction of fibre. For the aluminium matrix composites, the micrographs obtained show sound bonding between the adjoining foils and non‐bonding between the foil and steel wire. The tensile strength of the aluminium matrix composites is 80% of the value predicted by the rule of mixtures. For the titanium matrix composites, the micrographs obtained show both bonded and unbonded regions between the adjoining foils or between the foil and steel wire. The tensile strength of the titanium matrix composites agrees with the value predicted by the rule of mixtures. 相似文献
64.
Resolution of Epoxydienes by Reversed-Phase Chiral HPLC and its Application to Stereochemistry Assignment of Mulberry Looper Sex Pheromone 总被引:1,自引:0,他引:1
Guan-Qin Pu Masanobu Yamamoto Yaeko Takeuchi Hiroyuki Yamazawa Tetsu Ando 《Journal of chemical ecology》1999,25(5):1151-1162
Resolution of insect pheromonal cis-epoxydiene racemates derived from (Z,Z,Z)-3,6,9-trienes was examined with a reversed-phase chiral HPLC column. The results showed that a Chiralcel OJ-R column was suitable for separating the enantiomers having a C17–C23 unsaturated straight chain except for 9,10-epoxydienes with a C21–C23 chain. To determine the absolute configuration of the separated enantiomers, each of the optically active epoxydienes was hydrogenated over Pd-BaSO4 and its behavior was examined on this chiral column by cochromatography with the corresponding chiral epoxy compound having a saturated chain, which was prepared via a Sharpless epoxidation reaction. This analysis showed that the dextrorotatory C17–C23 3,4- and 6,7-epoxydienes and C17–C20 9,10-epoxydienes with shorter R
ts possess (3S,4R)-, (6S,7R)-, and (9R,10S) configurations, respectively, and the levorotatory enantiomers with longer R
ts possess the opposite configuration. An abdominal tip extract of the mulberry looper, Hemerophila artilineata Butler (Lepidoptera: Geometridae: Ennominae), included (9S,10R)-(Z,Z)-cis-9,10-epoxy-3,6-octadecadiene as a main sex pheromone component. The synthetic (9S,10R)-9,10-epoxydiene, rather than its antipode, elicited strong antennal and behavioral responses from the male moths in electrophysiological and field tests. 相似文献
65.
Kiyoharu Nakagawa Hirokazu Oda Akira Yamashita Masahiro Okamoto Yoichi Sato Hidenori Gamo Mikka Nishitani-Gamo Kazuyuki Ogawa Toshihiro Ando 《Journal of Materials Science》2009,44(1):221-226
We developed a novel spherical carbon material. The spherical carbon is composed of a high density of carbon nanotubes or
nanofilaments, and includes an oxidized diamond particle as a core. Syntheses of this carbon in high volume with high selectivity
may be possible. It is expected that this carbon will be useful as a catalyst material for fuel cells, electric double-layer
capacitors, etc. 相似文献
66.
Masuda Senichi Hosokawa Shunsuke Tachibana Naoji Ando Takashi Matsumoto Yoichi 《Industry Applications, IEEE Transactions on》1987,(1):120-126
The fundamental characteristics of the direct-coupled pulse energization in electrostatic precipitators (EP's) are investigated in a test rig comprised of a coal pulverizing facility, a furnace, a gas cooling system, and an EP. The EP consisted of a corona electrode with barbed wires and a collection electrode with 300-mm duct spacing. This simulates the type of EP normally used in a coal-fired power station. The pulse-energized collection field shows a very high collection performance of more than 99 percent collection efficiency and the performance enhancement compared to the conventional dc energization, causing very severe back corona, becomes as large as H = 2.50.H is the enhancement factor in terms of the Deutsch migration velocity in the case of the very high resistivity dust of rd = 2 x 1013 ?cm at the gas temperature of Tg = 150°C. Even at the lower level of the dust resistivity at Tg = 110°C, where no back corona occurs in the dc-energized collection field, the performance enhancement is as large as H = 1.21. The mechanism of such great performance enhancement is likely to be the result of the very uniform and very intense formation of corona plasmas on the wires as a result of the very fast rise in the pulse voltage applied and a special sawtooth waveform of the operating voltage between the corona and collection electrodes. 相似文献
67.
Shinji Ando Hideki Tonda Takushi Gotoh 《Metallurgical and Materials Transactions A》2002,33(3):823-829
The core structures of 〈c+a〉 dislocations in hexagonal-close-packed (hcp) metals have been investigated by molecular dynamics (MD) simulation using a
Lennard-Jones-type pair potential. The 〈c + a〉 edge dislocation has two types of core at 0 K; one is a perfect dislocation
(type A), and the other has two 1/2 〈c+a〉 partials (type B). Type A transforms to type B by abruptly increasing temperature from 0 K to 293 K, while type B is stable
in temperature range from 0 K to 293 K. In contrast, type A extends parallel to (0001) at 30 K, and this extended core is
still stable at 293 K. These results suggest that the 〈c+a〉 edge dislocation glides on the {11
2} as two 1/2 〈c+a〉 partial dislocations and becomes sessile due to changes of the core structure. The 〈c+a〉 screw dislocation spreads over two {10
1} planes at 0 K. The core transforms into a unsymmetrical structure at 293 K, which is spread over {11
2} and {10
1}, and core spreading occurs parallel to {11
2} at 1000 K. A critical strain to move screw dislocations depends on the sense of shear strain. The dependence of the yield
stress on the shear direction can be explained in terms of these core structures.
This article is based on a presentation made in the symposium entitled “Defect Properties and Mechanical Behavior of HCP Metals
and Alloys” at the TMS Annual Meeting, February 11–15, 2001, in New Orleans, Louisiana, under the auspices of the following
ASM committees: Materials Science Critical Technology Sector, Structural Materials Division, Electronic, Magnetic & Photonic
Materials Division, Chemistry & Physics of Materials Committee, Joint Nuclear Materials Committee, and Titanium Committee. 相似文献
68.
Mehta DS Sugai M Hinosugi H Saito S Takeda M Kurokawa T Takahashi H Ando M Shishido M Yoshizawa T 《Applied optics》2002,41(19):3874-3885
A noncontact, nonmechanical scanning, wide-field spectral interference microscope is developed for simultaneous measurement of three-dimensional step-height of discontinuous objects and tomographic imaging. A superluminescent diode (SLD) is used as a broadband light source and a liquid-crystal Fabry-Perot interferometer (LC-FPI) as a frequency-scanning device. By means of changing the injection current to the SLD, the spectral profile of the SLD is equalized, and a constant light input to the interferometer is achieved over the entire frequency-scan range. The Fourier-transform technique is used to determine both the amplitude and the phase of spectral fringe signals. Three-dimensional height distribution of a discontinuous object is obtained from the phase information, whereas optically sectioned images of the object are obtained either from the amplitude information alone or from the combination of both the amplitude and phase information. Experimental results with submicrometer resolution are presented for both step-height measurement and tomographic sectioning. 相似文献
69.
This paper presents calibration of the Vehicle Routing and scheduling Problems with Time Windows-Probabilistic (VRPTW-P) model
which takes into account the uncertainty of travel times. Probe vehicle data of travel times were obtained from usual operation
of pickup-delivery trucks in South Osaka area. The optimal solution of the VRPTW-P model resulted in reducing total cost,
running times and CO2, NOx and Particle Materials (PM) emissions compared with the usual operation. This is attributed to better routing of VRPTW-P
to choose more reliable roads. Therefore, VRPTW-P can contribute to establish efficient and environmentally friendly delivery
systems in urban area. 相似文献
70.
Pavel Grigorenko Ando Saabas Enn Tyugu 《Electronic Notes in Theoretical Computer Science》2005,141(4):137
A compiler-compiler for visual languages is presented. It has been designed as a framework for building visual programming environments that translate schemas into textual representation as well as into programs representing the deep meaning of schemas. The deep semantics is implemented by applying attribute grammars to schema languages; attribute dependencies are implemented as methods of Java classes. Unlike compiler-compilers of textual languages, a large part of the framework is needed for support of interactive usage of a visual language. 相似文献