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101.
Harumi Yokokawa Natsuko Sakai Teruhisa Horita Katsuhiko Yamaji Yueping Xiong Takanori Otake Hiroo Yugami Tatsuya Kawada Junichiro Mizusaki 《Journal of Phase Equilibria and Diffusion》2001,22(3):331-338
Phase diagram calculations that were made previously for the ZrO2-MO
m/2 (m = 2, 3, 4) systems and for the ZrO2-YO1.5-MO
m/2 (M = transition metals) systems have been extended to the ZrO2-YO1.5-CeO2(-CeO1.5) system to make an attempt to explain (1) thermogravimetric (TG) results as a function of oxygen potential, (2) electronic
conductivity as a function of oxygen potential, and (3) a miscibility gap observed in air. The interaction parameters for
the CeO2-CeO1.5-YO1.5 system were obtained from the reported oxygen nonstoichiometry in CeO2−x
and rate earth doped ceria, (Ce,RE)O2−δ
. The interaction parameters for the ZrO2-CeO2 subsystem were obtained so as to reproduce the observed miscibility gap at 1273 K. Those thermodynamic properties can reproduce
consistently the experimental behaviors of the electronic conductivity and the TG results in the (Zr1−x
Ce
x
)0.8Y0.2O1.9 solid solutions; these indicate the enhancement of reduction of CeO2. 相似文献
102.
103.
104.
105.
Spheroidization of Al grains is required for the production of semi-solid slurry either by a partial solidification route or partial re-melting route. In this research, A356 aluminum alloy was deformed and partially re-melted to semi-solid state. A segregation sensitive reagent (Weck’s reagent) was used to reveal the inner microstructure of Al grains for the better understanding of the microstructure evolution during partial re-melting. Optical microstructure observation showed that the previously compressed Al dendrites were actually “fractured” during heat treatment and such “fractured” dendrites contributed to the refinement and spheroidization of Al grains. Further study of this phenomenon indicates that the “fractures” are actually migrating high-angle grain boundaries, which was related to the recrystallization that occurred during heat treatment. Moreover, the growth layer of Al grains formed during water quenching is clearly visualized after being etched by Weck’s reagent. Consequently, precise evaluation of solid fractions through image analysis was realized by excluding growth layer when measuring the area of solid phase. 相似文献
106.
Hiroki Dobashi Junichi Hiraoka Takanori Fukao Yasuyoshi Yokokohji Akio Noda Hikaru Nagano 《Advanced Robotics》2014,28(15):1005-1019
In a robotic cell, assembly robots have to grasp parts in various shapes robustly and accurately even under some uncertainties in the initial poses of the parts. For this purpose, it is necessary to develop a universal robotic hand and robust grasping strategies, i.e. finger motions that can achieve planned grasping robustly against the initial pose uncertainty of parts. In this paper, we propose a methodology to plan robust grasping strategies of a universal robotic hand for assembling parts in various shapes. In our approach, parts are aligned toward planned configurations during grasping actions, and the robustness of grasping strategies is analyzed and evaluated based on pushing operation analysis. As an application example, we plan robust grasping strategies for assembling a three-dimensional puzzle, and experimentally verify the robustness and effectiveness of the planned strategies for this assembly task. 相似文献
107.
Yusuke Wakikawa Tadaaki Ikoma Yohei Yamamoto Takanori Fukushima Takuzo Aida 《Synthetic Metals》2010,160(3-4):275-279
By means of the integral mode time-of-flight measurement of the drift motion of the photoinjected charge at room temperature, we observed magnetic field effect (MFE) on the photocharge in self-assembled nanotube of hexabenzocoronene (HBC) at the configurations where the magnetic field is parallel and perpendicular to the electric field. The detected MFEs are interpreted in terms of two mechanisms that are caused by the fast charge transportation (Hall effect) and the spin selective recombination (electron–hole (e–h) pair mechanism). A high mobility in the nanotubes of π-stacked HBC was implied from the Hall data. The time dependence of the low field MFE due to the e–h pair mechanism clarified the recombination from both the singlet and triplet e–h pairs with the initial rate of ~108 s?1. 相似文献
108.
Kenji Shimomura Kazuaki Akasaka Arata Yajima Takanori Mimura Shunsuke Yajima Kanju Ohsawa 《Journal of chemical ecology》2010,36(9):955-965
Callosobruchus analis (Coleoptera: Chrysomelidae: Bruchinae), found throughout tropical Asia and Africa, is a pest of stored legumes. Previous
work has shown that females of this species produce a contact sex pheromone that elicits copulatory behavior in males. Comparisons
of copulatory activity between any two of four congeneric species suggest that the contact sex pheromones are species specific.
In laboratory bioassays, male C. analis exhibited copulatory behavior to a female dummy to which a crude extract of virgin females was applied. The extract had been
collected by a filter paper method and was purified by acid–base partition and chromatographic techniques. Gas chromatography-mass
spectrometry (GC-MS) analyses of active fractions revealed that the active compounds were 2,6-dimethyloctane-1,8-dioic acid
(1) and callosobruchusic acid, (E)-3,7-dimethyl-2-octene-1,8-dioic acid (2), previously identified as contact sex pheromones of Callosobruchus maculatus (F.) and C. chinensis (L.), respectively. The stereoisomeric and chemical compositions were determined by the 2D-HPLC-Ohrui-Akasaka method as (2S,6R)-1:(S)-2 = 1.8:1, which meant that both compounds in C. analis were stereochemically pure, unlike the case of C. maculatus and C. chinensis. An examination of the influence of synthetic pheromone compounds on male copulatory activity revealed that (2S,6R)-1 is the main component, and that (S)-2 has an additive effect. In the examination of the stereochemistry-activity relationship, no copulatory behavior was elicited
by (2R,6S)-1, and, furthermore, the enantiomer significantly masked the pheromonal activity of (2S,6R)-1. Glass rod dummy assays also suggested the presence of synergists. These results could elucidate the specificity of mate
recognition in C. analis. 相似文献
109.
110.
Yosuke Matsuo Yusuke Fujita Sachiko Ohnishi Takashi Tanaka Hideaki Hirabaru Takanori Kai Hiroshi Sakaida Shoko Nishizono Isao Kouno 《Food chemistry》2010
Chemical constituents of the leaves of rabbiteye blueberry (Vaccinium ashei READE) were investigated in detail. The major phenolic components were caffeoyl quinic acids, flavonol glycosides, flavan-3-ols and proanthocyanidins. Catechins and proanthocyanidins having additional phenylpropanoid units, such as cinchonains, kandelins and mururins, characterised the polyphenols of this plant. Among them, vaccinin A, an isomer of mururin A, was found to be a new compound, and the structure was characterised by spectroscopic methods. The most abundant polyphenols (11.3% of freeze-dried leaves) were oligomeric proanthocyanidins. Thiol degradation with mercaptoethanol indicated that the polymer was constituted of (+)-catechin and (−)-epicatechin as the terminal units and (−)-epicatechin, procyanidin A-2, and cinchonains Ia and Ib as the extension units. Mass spectral analysis suggested the presence of at least dodecamers with A-type linkages and phenylpropanoid moieties. 相似文献