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61.
Masaru Matsuoka Akihiro Iwamoto Takeshi Ouchi Hiroshi Yoshioka Kazumi Nakatsu 《Journal of heterocyclic chemistry》1993,30(1):173-176
The structure of 1,4-dithiines obtained from orthodihalogeno heterocycles with thiocarbonyl compounds was determined by X-ray structure analysis of the intermolecular charge-transfer complex between 5,7,12,14-tetramethoxydibenzo[b,i]thianthrene and TCNQ. The formation of the thiazole ring has already been reported but the products were confirmed to be 1,4-dithiines by X-ray structure analysis and the previously reported results. 相似文献
62.
Two crystalline forms (α and β) of poly(vinylidene fluoride) were studied by infrared spectroscopy. The spectral differences permitted the study of the transformation and the ratio of the two forms. The ordinary \documentclass{article}\pagestyle{empty}\begin{document}$ \vec G,\vec F $\end{document} matrix method was used to calculate the fundamental mode with a Urey-Bradley type potential field, and a preferred set of the force constants was obtained. 相似文献
63.
Hirokazu Takahara Shunji Nomura Hiromichi Kawai Yutaka Yamaguchi Kazumi Okazaki Akio Fukushima 《Journal of Polymer Science.Polymer Physics》1968,6(1):197-221
The dimensional stability of regenerated cellulose film on swelling with water is discussed in relation to the biaxial orientation of the two kinds of structural units, cellulose II crystallites and noncrystalline chain segments, and their anisotropic swelling (anisotropic absorption of water). Considerable dimensional stability in the plane of the film but enormous instability of thickness on swelling in water of some commercial cellophanes is qualitatively interpreted in terms of the planar orientation of crystal (101) planes along the film surface and the orientation of the noncrystalline chain segments parallel to the film surface. The dimensional changes on swelling from the completely dry state to 10% moisture regain were further interpreted quantitatively in terms of the degrees of biaxial orientation of the two kinds of structural units and their degrees of anisotropic swelling by modifying the Hermans monophase model for crystalline and noncrystalline biphase structures. The following degrees of anisotropic swelling of the structural units were thus obtained: qc, [101] = 0.40%, qc, [101 ] = ?0.33%, and qa = 2.42%. 相似文献
64.
We have investigated theoretically the Nernst effect in unconventional (d-wave) charge and spin density waves (UDW). In the presence of magnetic field, Landau levels are formed, and the gapless behaviour of the low energy excitations change into gapped behaviour. When additional electric field is applied, the quasiparticles drift with a velocity of E × B/B2, and carry entropy. From this, the Nernst coefficient can be calculated using the Kelvin relation. The present results account very nicely for the measured Nernst signal in the pseudogap phase of high Tc superconductor La2−xSrxCuO4 and Bi2Sr2−yLayCuO6. This indicates that the large Nernst effect is a clear signiture of UDW. 相似文献
65.
Shinichi Ueji Kazumi Nakatsu Hiroshi Yoshioka Kenji Kinoshita 《Tetrahedron letters》1982,23(11):1173-1176
The crystals of the title compound contain both intra- and inter-molecular OH?π hydrogen bonds (the first example of bifurcated OH?π bonds), the stereochemistry of which has been elucidated by an X-ray structure analysis; this bifurcated bond is also supported by the observation based on the IR spectrum of the crystals. 相似文献
66.
The present article reports a new optical method for real time addition or subtraction of two photographic images. Two transparencies which are placed in the two arms of a Mach-Zehnder interferometer with two orthogonal polarizers are subsequently added or subtracted by rotating an analyser inserted in the output beam. A linear combination of the amplitudes of the two images can also be observed for different orientations of the transmission axis of the analyser. Some experimental results are presented. 相似文献
67.
Watanabe Kazumi 《International Journal of Solids and Structures》1977,13(1):63-74
The well-known Cagniard's technique seems very useful for analyzing the transient problem of an elastic body subjected to a moving load with uniform velocity, but, in the cases of non-uniform velocity it would be difficult to apply the technique directly to analyze the problem. For such cases, instead of the technique, the convolution theorem of the Laplace transform or the dynamic Betti-Rayleigh reciprocal theorem has been applied usefully by many authors.In this paper, an inversion scheme which enables us to apply the Cagniard's technique directly to those difficult problems is presented by solving the problem of a reciprocating anti-plane shear load applied to a layered elastic half space. In this treatment it will be found clearly that our technique is simpler and more systematic than any other techniques for solving the problem. Numerical results are shown in the form of curves and the wave-front singularities are also investigated. 相似文献
68.
The first measurements of magnetization hysteresis loops on a diluted single crystal of [(Pc)2Ho]-.TBA+ (Pc = phthalocyaninato, TBA = tetrabutylammonium) in the subkelvin temperature range are reported. Characteristic staircase-like structure was observed, indicating the occurrence of the quantum tunneling of magnetization (QTM), which is a characteristic feature of SMMs. The quantum process in the new lanthanide SMMs is due to resonant quantum tunneling between entangled states of the electronic and nuclear spin systems, which is an essentially different mechanism from those of the known transition-metal-cluster SMMs. Evidence of the two-body quantum process was also observed for the first time in lanthanide complex systems. 相似文献
69.
Feng Dang Kazumi Kato Hiroaki Imai Satoshi Wada Hajime Haneda Makoto Kuwabara 《Ultrasonics sonochemistry》2010,17(2):310-314
A new effect of ultrasonic irradiation on the formation of BaTiO3 particles was identified. Ultrasonication caused the aggregation of the original 5–10 nm BaTiO3 particles in the same crystal axis and accelerated the formation of BaTiO3 particles significantly. Furthermore, narrow size distribution was obtained for the aggregated particles under ultrasonic irradiation. 相似文献
70.
Inagaki K Takatsu A Nakama A Eyama S Yarita T Okamoto K Chiba K 《Analytical and bioanalytical chemistry》2006,385(1):67-75
A method is described for determination of selenium in sediment by isotope-dilution inductively coupled plasma mass spectrometry
with an octapole reaction cell (ID–ICP–ORCMS). Sediment samples were digested with HNO3, HClO4, and HF, and the digestion included an elaborate evaporation process to remove bromine from the digested solution. Simple
strong cation-exchange disk filtration was used to remove rare earth elements (REE) from the digested solution, because REE2+ seriously interfere with Se isotopes (i.e. 156Gd2+ with 78Se+, 160Gd2+ with 80Se+). Addition of acetic acid to the filtrate was examined to improve the sensitivity of ICP–ORCMS measurement of Se+ by means of a carbon-enhancement effect. The interfering for selenium isotopes were almost eliminated by use of H2 as reaction gas. Interference from BrH+ formed in the reaction cell was negligible because the Br was removed in the evaporation process. Approximately 99.5% of
REE were removed by cation-exchange disk filtration yet more than 99% of Se remained in the filtrate solution. The intensity
for Se+ was enhanced approximately fourfold by addition of 5% (v/v) of acetic acid whereas that for was barely enhanced. Measured 80Se/78Se ratios in unspiked digested solutions of the sample were in good agreement with that for an Se standard solution. The analytical
results for Se in the certified reference materials MESS-3 and PACS-1 were in good agreement with their certified values,
with small uncertainties.
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