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91.
92.
Y. Kagawa T. Yamabuchi T. Yoshikawa S. Ooie N. Kyouno T. Shindou 《Journal of sound and vibration》1980,69(2):207-228
The present paper deals with acoustical systems with an opening to semi-infinite space for sound radiation. The approach is a combination of the finite element method and the analytical method. The finite element approach is used for the hollow internal space, while the analytical approach is utilized for the open semi-infinite space. The semi-infinite space is expressed in terms of an integral with respect to the opening surface (Green's theorem). Compatibility conditions are then introduced for the interface boundary. The region to which the finite element analysis is to be applied is thus greatly reduced at the expense of additional numerical integration. A computer program is developed and, for numerical demonstration, calculations of some characteristics of conical and exponential horns, and of a practical speaker device with central post and silencers are considered. Comparisons with the measured results confirm the validity of the approach. 相似文献
93.
94.
Hiroshi Akita Hiroto Kobayashi Tatsuya Hattori Kazuhiro Kagawa 《Journal of Polymer Science.Polymer Physics》1999,37(3):199-207
The copolymerization of a precursor of poly(p‐phenylene benzobisthiazole) (PBZT) with aromatic polyamides was attempted. Two types of copolymers, randomlike and blocklike, which have different properties, were synthesized according to the copolymerization process. The copolymers were suitable for use as the reinforcing polymer in molecular composite because of the improved intermolecular hydrogen bridges between the matrix polymers, such as aromatic polyamides, and then could be converted to the PBZT copolymers by heat treatment of the molecular composite. In particular, the possibility that the fine phase structure of the molecular composite was maintained was shown, even after heat treatment at above the melting temperature of the thermoplastic matrix polymer, due to the use of a PBZT copolymer as the reinforcing polymer, introduced a fragment which had the same molecular structure as in the matrix polyamides. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 199–207, 1999 相似文献
95.
Abstract
In this research, a flame arrester consisting of a slit structure was experimentally investigated. Experimental data show adequate maximum experimental safe gap (MESG) value for the flame arrester. The flow rate characteristics of the flame arrester were measured and compared with theoretical results. It was made clear that the flow impedance of convergent flow is 20% less than that of divergent flow. The experimental data and theoretical data show good agreement. The performance test by an EN12874 as ‘in-line stable detonation’ flame arrester was examined for a hydrogen–air gas mixture. The experimental data show that the gap was 0.2 times the MESG value in bi-directions for the flame arrester. The quenching and extinguishing processes were visualized by high-speed cameras. 相似文献96.
Y. Taguchi H. Sakai D. Okuyama S. Ishiwata J. Fujioka T. Fukuda D. Hashizume F. Kagawa Y. Takahashi R. Shimano Y. Tokunaga Y. Kaneko A. Nakao H. Nakao Y. Murakami K. Sugimoto M. Takata K. Yamauchi S. Picozzi A.Q.R. Baron T. Arima Y. Tokura 《Physica B: Condensed Matter》2012,407(11):1685-1688
Perovskite-type manganites exhibit various interesting phenomena arising from complex interplay among spin, charge, orbital, and lattice degrees of freedom. One such example is the keen competition between phases with different spin/charge/orbital orders. Keen competition between antiferromagnetic metal and orbital-ordered insulator is found in the slightly electron-doped regime near Mn4+ state which is stabilized by the high oxygen-pressure condition. Another one is the emergence of ferroelectricity either induced by the magnetic ordering or independently of the magnetic ordering. As the respective examples, perovskite-type YMnO3 and Sr1−xBaxMnO3 are discussed. In the YMnO3, the ferroelectric lattice distortion associated with the E-type spin order is observed for the first time. Displacement-type ferroelectricity with off-center magnetic ions is discovered for Sr0.5Ba0.5MnO3, which shows both large polarization value and strong coupling between ferroelectricity and magnetism. 相似文献
97.
Shibata N Nishimine T Shibata N Tokunaga E Kawada K Kagawa T Sorochinsky AE Soloshonok VA 《Chemical communications (Cambridge, England)》2012,48(34):4124-4126
Organic base-catalyzed reaction of (S)-N-tert-butanesulfinyl (3,3,3)-trifluoroacetaldimine with dialkyl malonates was found to be effective for synthesis of both (S,S(S)) and (R,S(S)) β-aminomalonates in high yield with good to excellent diastereoselectivity (76-98% de). The products of this Mannich reaction provide direct access to β-trifluoromethyl-β-alanine of either (R) or (S) absolute configuration. 相似文献
98.
Masayoshi?OkuboEmail author Yasuyuki?Kagawa Mitsuo?Matsuda Akinori?Terada 《Colloid and polymer science》2003,282(1):88-91
Polymer emulsion having ethyleneurea groups at particle surfaces was produced by emulsifier-free seeded emulsion copolymerization of n-butyl methacrylate (BMA) and methacrylamide ethylethyleneurea (EU) with poly(BMA) seed particles utilizing the starved-fed monomer addition method. This emulsion film, prepared by casting the polymer emulsion on an alkyd resin plate, had a superior adhesion in water, as well as on stainless steel. Such superior wet adhesions seem to be based on a large amount of EU predominantly localized at the particle surfaces.Part CCXLIX of the series "Studies on suspension and emulsion" 相似文献
99.
W. Hardjoutomo H. Munechika H. Kurniawan I. Hattori T. Kobayashi K. Kagawa 《Optics & Laser Technology》1992,24(5)
A compact capacitor-transfer TEA CO2 laser of 180 mJ output energy and 50 ns pulse duration in half width was designed and constructed for field use. This laser is suitable for laser microprobe spectrochemical analysis on geological and mining samples. Experiments show that the use of helium as a surrounding gas suppresses the continuous emission spectrum of the plasma, thus increasing the S/N ratio. Using glass as standard samples, the minimum detectable concentrations are estimated with Zn neutral line and F ionic line to be 60 ppm and 500 ppm, respectively. 相似文献
100.
A carrier protein mediating alanine transport was purified from the membranes of the thermophilic bacterium PS3, by ion exchange chromatography in the presence of both Triton X-100 and urea. The alanine carrier was recovered in the nonadsorbed fraction from either DEAE- or CM-cellulose columns, suggesting that its isoelectric point was in the neutral pH region. The final preparation contained virtually no electron transfer components, ATPase, or NADH dehydrogenase. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate revealed that the final preparation consisted of two major protein components with molecular weights of 36,000 and 9,400. Active transport of alanine after incorporation of the alanine carrier into reconstituted proteoliposomes was driven not only by an artificial membrane potential generated by potassium ion diffusion via valinomycin but also by mitochondrial cytochrome oxidase incorporated into the same liposomes and supplemented with both cytochrome c and ascorbic acid. The membrane-integrated portion (TFo) of the ATPase complex uncoupled alanine transport by conducting protons across the membrane. 相似文献