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91.
H. Suematsu J. Lindén M. Nagase M. Karppinen H. Yamauchi 《Journal of solid state chemistry》2004,177(6):1958-1964
The space group of the BaY(Cu0.5Fe0.5)2O5+δ (δ=0.03-0.17) phase was studied by selected-area electron diffraction and convergent-beam electron diffraction (CBED). The CBED patterns for BaY(Cu0.5Fe0.5)2O5.03 grains taken from the zone axes of [111], [001] and [010] had the symmetries of m, 4mm and 2mm, respectively. Forbidden reflections were observed neither in selected-area electron diffraction nor in the CBED patterns. From these results, the space group of the BaY(Cu0.5Fe0.5)2O5.03 was determined to be P4/mmm. Since the presence of a mirror plane parallel to the (Cu,Fe)O2 planes was confirmed, Cu and Fe were found to be randomly distributed in the (Cu,Fe)O2 planes. The same analyses were performed for BaY(Cu0.5Fe0.5)2O5.17 grains and the space group was also found to be P4/mmm. The change in the magnetic properties of BaY(Cu0.5Fe0.5)2O5+δ samples due to the high-pressure heat-treatment was concluded to be caused by excess of oxygen. 相似文献
92.
Analysis of crossovers and selections in a coarse-grained parallel genetic algorithm 总被引:1,自引:0,他引:1
Kengo Katayama Hisayuki Hirabayashi Hiroyuki Narihisa 《Mathematical and Computer Modelling》2003,38(11-13):1275
The parallel genetic algorithms (PGA) have been developed for combinatorial optimization problems, and its parallel efficiencies have been investigated on a specific problem. These investigations were concerned with how to design a topology and the determination of the optimum setting for parameters (for example, size of subpopulations, migration interval, and so on) rather than the effectiveness of genetic operators. This paper investigates a relation between the parallel efficiency of the coarse-grained PGA and genetic (crossover and selection) operators for the traveling salesman problem on an MIMD parallel computer. The following genetic operators are considered: improved edge recombination (IERX), distance preserving (DPX), and complete subtour exchange (CSEX) crossovers, and two selection operators, which have relatively high selection pressures. Computational results indicate that the parallel efficiency is significantly affected by the difference of crossovers rather than the selections, and the PGA with CSEX gives better properties. 相似文献
93.
94.
95.
In some invariant estimation problems under a group, the Bayes estimator against an invariant prior has equivariance as well. This is useful notably for evaluating the frequentist risk of the Bayes estimator. This paper addresses the problem of estimating a matrix of means in normal distributions relative to quadratic loss. It is shown that a matricial shrinkage Bayes estimator against an orthogonally invariant hierarchical prior is admissible and minimax by means of equivariance. The analytical improvement upon every over-shrinkage equivariant estimator is also considered and this paper justifies the corresponding positive-part estimator preserving the order of the sample singular values. 相似文献
96.
Nagayuki Kaneshiro Yang Xiang Kouhei Nagai Manae S Kurokawa Kazuki Okamoto Mitsumi Arito Kayo Masuko Kazuo Yudoh Takashi Yasuda Naoya Suematsu Kenjiro Kimura Tomohiro Kato 《Rapid communications in mass spectrometry : RCM》2009,23(23):3720-3728
We analyzed serum short peptides comprehensively to know whether they were useful to characterize IgA nephropathy (IgAN). Serum samples from 26 patients with untreated IgAN and 25 healthy donors were tested. Short peptides with molecular weights of ~7 kDa, purified from the serum samples by magnetic‐beads‐based weak cation exchange, were detected by mass spectrometry. Then the peptide peaks detected were subjected to the multivariate data analysis by SIMCA‐P+® containing principal component analysis (PCA) and orthogonal partial‐least‐squares‐discriminate analysis (OPLS‐DA). A total of 92 peptide peaks were detected in the tested serum samples. The OPLS‐DA analysis revealed that the profile of all the peptide peak intensities discriminated the IgAN group and the healthy group completely with a high R2 value (0.919) and a high Q2 value (0.861). Further, the profile of only five peptide peaks was found to discriminate the two groups. By tandem mass spectrometry and database searching, three of the five peptides which increased in the IgAN group were identified as fragments of fibrinogen alpha chain, and the two peptides which increased in the healthy group were identified as fragments of complement C3f and kininogen‐1 light chain. Taken together, the profile of the serum short peptides would be useful to discriminate IgAN and healthy conditions. Further, the five peptides may be candidate serum markers for IgAN and may be related to pathogenesis of IgA. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
97.
Suguru Motokucho Akito Yamaguchi Yu Nakayama Hiroshi Morikawa Hisayuki Nakatani 《Journal of polymer science. Part A, Polymer chemistry》2017,55(12):2004-2010
We have demonstrated a hydrolysis reaction of polyurethane (PU) under high pressure of carbon dioxide (CO2) in water. We employed the PU sample, poly(methylene bis‐(1,4‐phenylene)hexamethylene dicarbamate), denoted as M‐PU, which was synthesized from 4,4′‐diphenyl methane diisocyanate and 1,4‐butane diol (BD). The optimum hydrolysis reaction condition was 190 °C under CO2 pressures over 4.1 MPa in water medium, and 93% hydrolysis of M‐PU was achieved. After the reaction, the water‐soluble parts were obtained, and isolated by column chromatography. The isolated products were 4,4′‐methylenedianiline (MDA) and 1,4‐butane diol (BD), which were components of repeating unit of M‐PU. In addition, the hydrolysis reaction gave no byproduct. This hydrolysis under high pressure of CO2 with water is a reaction by which M‐PU is selectively hydrolyzed into MDA and BD by cleaving urethane linkage. Moreover, the resulting hydrolyzed products were easily obtained by evaporation of aqueous layer after the reaction, indicating an efficient chemical recycling of PU was achieved. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2004–2010 相似文献
98.
The critical temperature Tc, and the angular and temperature dependences of the upper critical field Hc2 in highly oriented pseudo-single crystals of C8K have been studied by using a magnetic susceptibility measurement. The magnetic susceptibility abruptly changes around 139 mK at zero field. The angular dependence of Hc2 shows a very large anisotropy. 相似文献
99.
Kazuhito Furuya Yasuharu Suematsu Hideharu Tokiwa 《Optical and Quantum Electronics》1978,10(4):323-330
Mode coupling coefficients and coupling lengths are determined for multimode fibres with general index distributions in the case where random bending is the main cause of mode coupling. It is shown that the product of the coupling length and the coupling-induced loss is determined only by the shape of the index distribution, and that the coupling length of the focusing fibre is about four times longer than that of the step-index fibre when the coupling-induced losses of both fibres are equal. 相似文献
100.
A mixture of copper and carbon powders was mechanically alloyed in a planetary ball mill. The supersaturated solid solubility of carbon in mechanically-alloyed copper is 25 v at% C, as determined from the lattice parameter change. The supersaturated powder consolidated by static compression at 1.4 v GPa, has the relative density of 95%, a Vickers hardness of 121, and a compressive strength of 1.4 v GPa. In contrast, powder consolidated dynamically by a 90.1 g projectile traveling at a velocity of 38.1 m/s and at an estimated impact compression of 2.3 GPa after 0.4 GPa static precompression has a relative density of 96.3% and a Vickers hardness of 200. X-ray diffraction patterns shift to higher angles after impact compression. The supersaturated solid solubility of 18 at% C in Cu+20 at% C mechanically-alloyed powders was reduced to 12.5 at% C by impact compression. Mechanically-alloyed powders can be consolidated by impact and static pressures while retaining the effects of mechanical alloying; for example, supersaturated solid solubility. 相似文献