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41.
The infrared chemiluminescence technique has been applied to the catalytic oxidation of CO on a Pt(110)(1×2) surface. The
vibrational and the rotational states of CO2 formed on the reconstructed Pt(110)(1×2) surface are more excited than those on the terrace Pt(111) surface. The vibrational
state of the product CO2 strongly depends on the CO coverage: the vibrational temperature (TV) of the product CO2 becomes higher, as the coverage of CO increases.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
42.
Ikuo Yanase Sachiko Tamai Hidehiko Kobayashi 《Journal of the American Ceramic Society》2003,86(8):1360-1364
Cubic cesium leucite-based compounds, namely cesium leucites, cesium sodium leucites, and cesium lithium leucites, were synthesized using a multistep solid-state reaction method. The thermal expansion properties, in the temperature range of 298-1273 K, for the synthesized cubic cesium leucite-based compounds were examined using high-temperature powder X-ray diffractometry data. The thermal expansions of the cubic cesium leucite-based compounds were found to vary with the chemical composition. For instance, the thermal expansions of Cs0.7 Na0.2 Al0.9 Si2.1 O6 and Cs0.7 Li0.2 Al0.9 Si2.1 O6 were 0.14% at 1273 K and 0.081% at 1073 K, values lower than those of Cs0.9 Al0.9 Si2.1 O6 , which were 0.16% at 1073 K and 0.2% at 1273 K. The results showed that the thermal expansions of the cubic cesium leucite-based compounds changed with ionic substitution at the Cs+ sites because of ionic size differences between Cs+ and the Na+ or Li+ substitutional ions. 相似文献
43.
Phase equilibria in Fe-Cu-X (X: Co, Cr, Si, V) ternary systems 总被引:2,自引:0,他引:2
Cui Ping Wang Xing Jun Liu Ikuo Ohnuma Ryosuke Kainuma Kiyohito Ishida 《Journal of Phase Equilibria and Diffusion》2002,23(3):236-245
Phase equilibria on the Fe-Cu side in the Fe-Cu-X (X: Co, Cr, Si, V) system were experimentally determined over the temperature
range of 1073–1273 K. Based on the present results and previous works, the thermodynamic assessments of the phase equilibria
in the Fe-Cu-X system were evaluated using the Calculation of Phase Diagram (CALPHAD) method. The Gibbs energies (G) of the bcc, fcc, and liquid phases are described by the subregular solution model, and a set of thermodynamic parameters
enable us to calculate various isothermal and vertical sections and the miscibility gaps of the solid and liquid phases. 相似文献
44.
Kojima T Karasawa S Miyawaki A Tsumuraya T Fujii I 《Journal of Bioscience and Bioengineering》2011,111(4):397-401
For high-throughput screening of protein-protein interactions, we have developed a novel yeast screening system using Bimolecular fluorescence complementation (BiFC). Two yeast plasmids, in which genes of heterodimerized peptides LZA and LZB were each fused with those of non-fluorescent half fragments of Kusabira-Green mutant (mKG2), were transformed into a- and α-type yeast, respectively. Mating of them gave a library, which was screened by following green fluorescence resulted from LZA-LZB interaction. The method showed potential ability to detect the positive clones from a model library, in which green-fluorescent and non-fluorescent yeast was mixed in a ratio of 1:675. 相似文献
45.
Voids are representative of the damage process in both creep and ductile fractures. Although the matrix/precipitate interface
has been considered the preferential nucleation site for voids, the relationship between the atomic structure of this interface
and the nucleation mechanism of a void has never been sufficiently investigated. In this study, the bcc Fe/V4C3 interface is selected as a model interface between a matrix and precipitate. The vacancy formation energy and intrinsic mechanical
strength at this interface are investigated using a first-principles calculation because they should be related with the nucleation
of creep and ductile voids, respectively. Within the considered interface, the Fe vacancy is found to be dominant. When the
Baker–Nutting orientation relationship is satisfied at the interface, the calculated intrinsic mechanical strength of the
interface is 23.8 GPa. However, when the geometric coherence at the interface is low as compared to that of the Baker–Nutting
orientation relationship, it is found that the interfacial mechanical strength is significantly weakened. At each interface,
it is found that the back-bond of the interface determined the interfacial strength because of the strongly bonded Fe–C on
the interface. The nucleation mechanism of a void at the matrix/precipitate interface is discussed based on the present findings.
It is suggested that local decohesion at the matrix/precipitate interface should be the origin of the nucleation of a ductile
void. 相似文献
46.
Ivan Gratchev Masyhur Irsyam Ikuo Towhata Bakhtiar Muin Hasbullah Nawir 《Soils and Foundations》2011,51(2):333-341
This paper reports and discusses the results of a field survey conducted by a joint scientific group from Japan and Indonesia to assess the geotechnical aspects of the Sumatra earthquake (Mw=7.6) of September 30, 2009. The studied area included the Padang and Pariaman cities, where a number of buildings collapsed as a result of strong shaking, and a mountainous part of the Pariaman district, a place where massive landslides buried several villages, claiming more than 400 human lives. The main objective of the survey was to investigate the causes and mechanisms of catastrophic landslides; however, other geotechnical problems such as lateral spread and liquefaction were also addressed. Field observations indicated that the catastrophic landslides occurred on relatively gentle slopes, then mobilized into debris flows, and traveled several hundred meters from their points of origin. The failure surfaces developed along the boundary of highly weathered pumice tuff with more intact and less weathered bedrock. Data from a portable cone penetration test showed that the sliding material was rather weak, having SPT N-values in the range of 5-10. The results of the field survey suggested that the main cause of slope instability was high pore-water pressures that generated in the soil mass during the earthquake. 相似文献
47.
Tien-Hsiu Tsai Takumi Hamaguchi Ikuo Kanno 《Journal of Nuclear Science and Technology》2018,55(6):663-671
The filter-type ‘transXend’ detector is an energy-resolving X-ray detector consisting of an energy-integrating flat-panel detector and multiple filters. In our previous studies, we have shown the effectiveness of the transXend detector, but the filters used were not optimized. To obtain better performance, the filters, especially their thickness and material, should be considered. In this paper, we present a method that can preliminarily estimate filter performance by comparing their noise sensitivity before carrying out numerous experiments. Two kinds of filter sets, Cu–Sn and W–Ag, with various thicknesses were evaluated. The results suggest that to image a 20-cm-thick object with 120-kV X-rays, an unfiltered channel and a channel filtered with 0.5-mm-thick Sn or 0.4-mm-thick Ag may be the best combination. The optimal filter thickness will be smaller if the object is thinner and the tube voltage is lower. For applications that require a wide dynamic range of detector response, a channel with a W filter may be better than an unfiltered channel. To verify the calculation results, computed tomography imaging experiments with a 3-cm-diameter phantom were also performed, and the experimental results showed good agreement with the calculation results. 相似文献
48.
49.
Ikuo Kanno Yoshiki Yamashita Eri Kanai Tsuyoshi Ogawa Kiyomitsu Shinsho 《Journal of Nuclear Science and Technology》2016,53(2):258-262
The “transXend” detector measures X-rays as electric currents and provides the energy distribution of the measured X-rays after analysis. Capabilities of material distinction, effective atomic number measurement, and low-dose exposure computed tomography (CT) with high K-edge contrast agent from the use of the transXend detector in energy-resolved CT have been demonstrated via the first-generation CT measurements. For application of the principle of the transXend detector to the third-generation CT for human subjects in future work, a method for fabrication of a two-dimensional transXend detector is proposed and demonstrated using a commercial two-dimensional detector and two kinds of strip absorbers. The energy-resolved CT is performed by placing a proposed absorber system in front of a two-dimensional detector, which is used for conventional current measurement CT. 相似文献
50.
Local damage to reinforced concrete structures caused by impact of aircraft engine missiles Part 1. Test program, method and results 总被引:3,自引:0,他引:3
T. Sugano H. Tsubota Y. Kasai N. Koshika H. Ohnuma W.A. von Riesemann D.C. Bickel M.B. Parks 《Nuclear Engineering and Design》1993,140(3):387-405
Structural damage induced by an aircraft crashing into a reinforced concrete structure includes local damage caused by the deformable engines, and global damage caused by the entire aircraft. Local damage to the target may consist of spalling of concrete from its front face together with missile penetration into it, scabbing of concrete from its rear face, and perforation of missile through it. Until now, local damage to concrete structures has been mainly evaluated by rigid missile impact tests. Past research work regarding local damage caused by impact of deformable missiles has been limited. This paper presents the results of a series of impact tests of small-, intermediate-, and full-scale engine models into reinforced concrete panels. The purpose of the tests was to determine the local damage to a reinforced concrete structure caused by the impact of a deformable aircraft engine. 相似文献