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51.
Electrical resistivity and thermopower of (La1−xSrx)MnO3 and (La1−xSrx)CoO3 at elevated temperatures
T. Ohtani K. Kuroda K. Matsugami D. Katoh 《Journal of the European Ceramic Society》2000,20(16):105-2726
Electrical resistivity and Seebeck (S) measurements were performed on (La1−xSrx)MnO3 (0.02x0.50) and (La1−xSrx)CoO3 (0x0.15) in air up to 1073 K. (La1−xSrx)MnO3 (x0.35) showed a metal-to-semiconductor transition; the transition temperature almost linearly increased from 250 to 390 K with increasing Sr content. The semiconductor phase above the transition temperature showed negative values of S. (La1−xSrx)CoO3 (0x0.10) showed a semiconductor-to-metal transition at 500 K. Dominant carriers were holes for the samples of x0.02 above room temperature. LaCoO3 showed large negative values of S below ca. 400 K, indicative of the electron conduction in the semiconductor phase. 相似文献
52.
Phase equilibria of Sn-In based micro-soldering alloys 总被引:1,自引:0,他引:1
I. Ohnuma Y. Cui X. J. Liu Y. Inohana S. Ishihara H. Ohtani R. Kainuma K. Ishida 《Journal of Electronic Materials》2000,29(10):1113-1121
The phase equilibria of Sn-In-X (X=Ag, Bi, Sb, Zn), the most basic information necessary for the development of Pb-free micro-soldering
alloys, were studied using the CALPHAD method. Thermodynamic analyses for describing the Gibbs energies of the constituent phases were made by optimizing the obtained
data on the experimental phase diagrams, and such data in the literature, including data on thermochemical properties. The
present results combined with the thermodynamic database which was recently developed by our group [I. Ohnuma et al., J. Electron. Mater. 28, 1164 (1999)] provide various information on phase equilibria such as liquidus and solidus surfaces, isothermal and vertical
section diagrams, mole fractions of the phase constitutions, etc., and thermodynamic properties such as activity, heat of
mixing, surface energy, viscosity, etc., in multi-component soldering alloy systems including the elements of Pb, Bi, Sn,
Sb, Cu, Ag, Zn, and In. Typical examples for the phase diagrams and thermodynamic properties of Sn-In-X ternary systems are
shown. The application of the database to the alloy design for Pb-free solders is also presented. 相似文献
53.
Synthesis of binary copper chalcogenides by mechanical alloying 总被引:2,自引:0,他引:2
Copper sulfides (tetragonal Cu1.92S-Cu1.99S, rhombohedral Cu1.71S-Cu1.89S, CuS), selenides (β Cu2 − xSe, Cu3Se2, γ CuSe, CuSe2), and tellurides (Cu2 − xTe, Cu3Te2) were prepared from mixtures of the elements by mechanical alloying (MA), using a high-energy ball mill. The compounds were obtained by 60–120 min of MA. It is notable that two metastable high-pressure phases were obtained by MA: tetragonal Cu2 − xS and pyrite-type CuSe2. The tetragonal phase gradually transformed to the stable phase of djurleite when kept at room temperature. Cu1.71S-Cu1.89S also formed a metastable rhombohedral phase. 相似文献
54.
The present study assessed the dynamic person–object relationship in pictorial perception as associated with a high-level experience like the aesthetic. A series of experiments was designed to gain insight into the complexities of self–world interactions involving the perceptual experience, which is the basis of artistic communication. Participants were asked to produce line drawings, which were then ranked by a larger group of participants as to whether they conveyed expressive contents. This resulted in considerable agreement among the judges. In addition, the factor structure of the semantic differential responses was determined. The results indicated that considerable semantic space existed between them. A theory of a linkage between affective and cognitive processes in perceptual experience is proposed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
A novel bacterial rhodopsin was identified in Haloarcula japonica strain TR-1. The gene encoding the bacterial rhodopsin was cloned and sequenced. The structural gene consisted of an open reading frame of 750 nucleotides encoding 250 amino acids. The deduced amino acid sequence of the Ha. japonica bacterial rhodopsin showed the highest homology to those of cruxrhodopsins. 相似文献
56.
J Yamamoto Y Shimamura H Nakahara Y Koishi M Kougo H Ohtani H Watanabe M Ishii M Ohmura 《Canadian Metallurgical Quarterly》1997,132(7):785-788
The leakage of pancreatic juice is the most serious complication after pancreatoduodenectomy. In an attempt to lessen the incidence of this complication, we have developed a simple technique for the anastomosis of pancreatogastrostomy. Since March 14, 1995, we have already performed surgical procedures on 8 cases of pancreatogastrostomy using this technique and as yet have never experienced fatal complications. We report the autopsy findings of pancreatogastric anastomosis histologically. The specimen taken from the anastomosis reveals good mucosal continuity. This result suggests the importance of reliable sutures between the pancreatic parenchyma and the full thickness of the gastric wall for the anastomosis of pancreatogastrostomy. 相似文献
57.
Huzo Kato Kohichi Ohtani Takehru Kohri Masahiro Morikura Masahiro Umehira Shuji Kubota 《International Journal of Satellite Communications and Networking》1988,6(3):289-300
Devices and architectures for on-board SCPC (single channel per carrier) multi-carrier demodulators suitable for use in satellites to be launched between the present and the year 2000 are discussed in the light of trends in the development of device technology towards lower on-board weight and power consumption. It is shown that at the present time (equivalent to about 1990 for on-board use). The choice of demodulation scheme depends on the number of channels available for regeneration on board the satellite. The total weight and power consumption for several suitable on-board multicarrier demodulation schemes are predicted for 1990, 1995 and 2000, as functions of the number of channels to be regenerated. 相似文献
58.
T Hosoki M Mitomo S Chor N Miyahara M Ohtani K Morimoto 《Canadian Metallurgical Quarterly》1997,38(3):422-427
PURPOSE: To assess the visualization of tumor vessels in hepatocellular carcinoma (HCC) by power Doppler sonography. MATERIAL AND METHODS: We examined 40 patients with 47 HCC lesions by means of power Doppler sonography and compared its visualization of tumor vessels with those of color Doppler and angiography. RESULTS: In 38 (81%) of the 47 lesions, power Doppler sonography improved the visualization of tumor vessels compared with color Doppler sonography; in the remaining lesions no significant difference was noted. In lesions located within 7 cm in depth, there was no significant difference between power Doppler sonography and angiography. In 10 (83%) out of 12 small (< or = 2 cm in diameter) lesions and in 11 (85%) out of 13 hypovascular lesions, power Doppler sonography performed considerably better than angiography. In deeper-seated lesions, however, angiography was significantly superior to power Doppler sonography. CONCLUSION: Power Doppler sonography is more sensitive in detecting the fine tumor vessels in most HCCs than color Doppler sonography. In addition, power Doppler sonography can replace angiography in evaluating tumor vascularity in HCCs except in lesions that are deep-seated or located near the heart. In these lesions, angiography can complement power Doppler sonography in demonstrating tumor vessels. 相似文献
59.
60.
Friction opposes tooth motion whenever sliding mechanics is employed. Understanding what friction is and how to manage it is of paramount importance to the successful practitioner. In this article, the coefficients of friction are summarized between different arch wire-bracket couples as a function of material, geometric, and external parameters. From this vantage point, friction can then be evaluated within the context of other factors that affect sliding-binding and notching. 相似文献