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381.
Koichi Hatada Yoshio Terawaki Tatsuki Kitayama Mikiharu Kamachi Masami Tamaki 《Polymer Bulletin》1981,4(8):451-458
Summary Polymerizations of vinyl acetate were carried out with AIBN in benzene, chlorobenzene and ethyl acetate, and the resultant polymers were analyzed for terminal group by using 1H NMR technique. The results revealed that a part of the polymer molecules prepared in aromatic solvent contained one solvent fragment at the chain end, indicating the incorporation of aromatic molecule through the chain transfer reaction and not by the copolymerization. It was found that there existed at least 0.7 branching per a molecule in the polymer prepared in ethyl acetate, whereas almost no branching in the polymer prepared in aromatic solvents. 相似文献
382.
383.
384.
Tsuyoshi Nishi Masami Nakada Chikashi Suzuki Mitsuo Akabori 《Journal of Nuclear Materials》2008,374(3):339-343
EXAFS and XANES analyses were applied in a study of americium dioxide (AmO2) with fluorite structure. EXAFS result for Am-LIII absorption edge of AmO2 was in good agreement with the long-ranged structural data from X-ray diffraction analysis. In order to characterize XANES in aspect of the electronic structure, the theoretical assignment for the AmO2 was performed with the relativistic DV-Xα molecular orbital method. The calculated XANES spectrum well reproduced the experimental spectrum. From this theoretical assignment, it was found that the peaks of the XANES spectrum were created due to the specific hybridization of orbital components. 相似文献
385.
Shinya Otsuka Masami Matsuyama Zensaku Kozuka 《Metallurgical and Materials Transactions B》1978,9(2):21-24
The oxygen diffusivity in liquid copper-lead alloys at 1403 K (1130‡C) was measured us-ing the electrochemical cell: Ni-NiOJZrO2(+CaO)/O in liquid Cu-Pb alloy(I)/ZrO2(+CaO)/O in liquid Cu-Pb alloy(II). Oxygen in liquid Cu-Pb alloy(I) was transferred to the right by applying a preselected
voltage between the two liquid Cu-Pb alloys. The oxygen diffusivity in liquid Cu-Pb alloy(I) was calculated from the emf change
with time between the Ni-NiO and liquid Cu-Pb alloy (I) electrodes. The results were: Do (in pure Cu) = 8.14 (+0.70
-0.43) × 105 cm2/s, Do (in Cu-25 at. pct Pb) = 11.4(+0.4
-0.6) × 10-5 cm2/s, Do (in Cu-50 at. pct Pb) = 12.9(+1.9
-1.5) × 10-5 cm2/s, Do (in Cu-75 at. pct Pb) = 11.0(+2.4
-1.2) x 10-5 cm2/s, Do (in pure Pb) = 26.3(+4.8
-3.7) × 10-5 cm2/s. It was found that the oxygen diffusivity in liquid copper-lead alloys did not change dras-tically over the entire composition
range, in contrast with that reported by other investi-gators for liquid copper-nickel alloys. The oxygen diffusivity in pure
liquid lead agreed with the results of our previous work using an FeO-Fe3O4 mixture as a sink for oxygen. 相似文献
386.
Masahiro Tatsumisago Ikuo Sakono Tsutomu Minami Masami Tanaka 《Journal of Materials Science》1982,17(12):3593-3597
In the systems R2O-WO3 (R=Li, Na, K), the glass-forming region was extended by use of the rapid quenching technique combining a thermal-image furnace with a twin roller. The infra-red spectra revealed that the Li2WO4 glass contains no condensed macro-anions but only discrete ions of Li+ and WO
4
2–
. The glass transition temperature (T
g) and the crystallization temperature (T
c) were determined.T
g is affected very slightly by the type of alkali cations, whereas it is decreased with increase in the alkali oxide content. More than oneT
g was observed in Li2O-WO3 glasses, which is due to the formation of metastable phases. The conductivity of glasses containing the same amount of alkali oxide (of different types) increased with decrease in the radius of the alkali cation. Electrochromism was observed in the glasses with R=Li, Na; the electric field required for colouration is lower than that in WO3 films. The electro-colouration is due to HxWO3 formed in the glass matrix by the double injection of protons and electrons. 相似文献
387.
Current-mode highpass, bandpass and lowpass filters using the operational amplifier pole 总被引:2,自引:0,他引:2
Masami Higashimura 《Microelectronics Journal》1993,24(8):863-866
The use of the Operational Amplifier (OA) pole has received much attention for its potential advantages of miniaturization, ease of design and high frequency performance. This paper proposes a novel circuit configuration for realizing current-mode filters using the OA pole. The circuit realizes simultaneously highpass, bandpass and lowpass transfer functions. Since the circuit uses the OA pole, it is suitable for high frequency operation. 相似文献
388.
Toshiyuki Tamai Masaya Chigane Kimihiro Matsukawa Masami Ishikawa Hiroshi Inoue 《应用聚合物科学杂志》2002,83(6):1305-1308
Polymer gel electrolytes were investigated for an electrochromic device (ECD) using nickel oxide thin film. Poly(ethylene oxide) (PEO) derivatives were cross‐linked and swelled in KOH–aqueous solution giving a hydrogel electrolyte. The ECD containing the uniformly cross‐linked hydrogel showed good result in electrochromic switching performance. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1305–1308, 2002 相似文献
389.
Seiji Katayama Satoshi Kawaguchi Masami Mizutani Yousuke Kawahito Taishi Tarui 《Welding International》2013,27(10):753-762
Laser welding of aluminium alloys is difficult because of their low laser coupling, easy formation of welding defects, etc. and thus the establishment of in process monitoring technique is expected in various industries to obtain highly reliable laser welds. In this study, therefore, both the reflected laser beam and radiation light from die molten pool were investigated as monitoring signals during YAG laser welding of A5052 and A5182 aluminium alloy to confirm validity and usefulness of these signals for monitoring. At the same time, laser-welding phenomena were observed through a high-speed video camera to better interpret the monitored signals. Two signals were detected by utilizing photo sensors and band pass or cut-off filters coaxially against a laser beam and from the above-back direction. In this paper, experimental setup, and monitoring and observation results were presented. The correlation between monitoring signals and welding phenomena was clarified when the welding defects such as underfilling and through holes were formed. 相似文献
390.
Practising to operate an unknown system and observing the input and output of the system, in a sense, helps to optimally control that system. The acquired knowledge, is, in turn, used to solve future analogous control problems. This means that it is very important to know how to memorize the acquired knowledge and to utilize it for learning. In this paper, we propose a new knowledge representation and reasoning method and develop a learning machine (KBLC: Knowledge-Based Learning Controller) by using them. A simple implementation has been constructed that demonstrates the feasibility of building such a machine. 相似文献