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Kensuke Naka Akiko Kobayashi Yoshiki Chujo 《Macromolecular rapid communications》1997,18(12):1025-1032
The star-shaped polymer with trans-tetrapyridyl complex of Ru(II) as a core was prepared by complexation of ester-linked pyridyl-terminated poly(oxyethylene) (M̄n = 2000) with a Ru5Cl122− cluster. The unimodal peak of the star-shaped polymer in the gel-permeation chromatogram was shifted to a higher molecular weight region than that of the starting prepolymer. The electron-withdrawing ester substituent in para position of the pyridine ring shifted the metal-to-ligand charge transfer (MLCT) band into the visible region. 相似文献
264.
The miscibility of polyvinylphenol (PVPh) or terpenephenol (TPh) with polyoxymethylene (POM) was examined by high-resolution solid-state 13C nuclear magnetic resonance (NMR) spectroscopy. It was found that the driving force for the mixing of POM and PVPh is the hydrogen-bonding interaction between the phenolic OH group of PVPh and the ether oxygen of POM, and that the mixing is preferentially induced in the noncrystalline phase. 1H relaxation time experiments indicated that POM/PVPh blends were homogeneous on a scale of 20–30 nm but heterogeneous on a scale of 2–3 nm. On the other hand, Fourier transform infrared and cross-polarization/magic-angle-spinning 13C-NMR (nuclear magnetic resonance) spectra revealed that POM and TPh are also mixed in the noncrystalline phase through the intermolecular hydrogen-bonding interaction, while some fraction of POM is still crystallizable. Moreover, the domain size of the micro-phase separation was estimated to be about 1 nm by the direct 1H spin-diffusion measurements, suggesting almost homogeneous mixing on a molecular level in the noncrystalline phase. © 1997 John Wiley & Sons, Ltd. 相似文献
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We have observed several kinds of hydrocarbon cations after the nanosecond and the femtosecond laser ablation (nsLA and fsLA) of solid C60. The observation indicates that the carbon fragments produced just after laser ablation of the C60 molecule react with the hydrogen atoms and ions coexisting in the ablation plume. In the case of fsLA, clear dependence of the product hydrocarbon species on the ablation laser power has been observed although the dependence is not clearly observed in nsLA. The production of CnH5+ (n = 8, 10, and 12) is only observed in fsLA suggesting the unique nature of the transient carbon fragments produced by fsLA. 相似文献
268.
Yoshinori Matsuo Sang-Jin Sin Shingo Takeuchi Takuya Tsukioka Chul-Moon Yoo 《Nuclear Physics B》2009,820(3):593-619
In the previous paper we studied the transport coefficients of quark–gluon plasma in finite temperature and finite density in vector and tensor modes. In this paper, we extend it to the scalar modes. We work out the decoupling problem and hydrodynamic analysis for the sound mode in charged AdS black hole and calculate the sound velocity, the charge susceptibility and the electrical conductivity. We find that Einstein relation among the conductivity, the diffusion constant and the susceptibility holds exactly. 相似文献
269.
Keiji Enpuku Tsuyoshi Tanaka Yuya Tamai Masaaki Matsuo 《Journal of magnetism and magnetic materials》2009,321(10):1621-1624
AC susceptibility of magnetic markers in solution was studied for biosensor applications. First, frequency dependence of the susceptibility was measured, and size distribution of the markers was estimated by analyzing the experimental result with the so-called singular value decomposition (SVD) method. The size distribution estimated with the magnetic measurement agreed with that obtained from conventional optical measurement. Next, susceptibility measurement was applied to the liquid-phase immunoassay without bound/free (B/F) separation. We performed the detection of biotin-coated polymer beads in suspension using avidin-coated magnetic markers. Changes of the susceptibility and the size distribution caused by the binding reaction were shown. 相似文献
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A Galerkin scheme is presented for a class of conservative nonlinear dispersive equations, such as the Camassa–Holm equation and the regularized long wave equation. The scheme has two advantageous features: first, it is conservative in that it keeps the discrete analogue of the continuous energy conservation property in the original equations; second, it can be formulated only with cheap H1-elements even if the original equations include third derivative uxxx. Numerical experiments confirm the stability and effectiveness of the proposed scheme. 相似文献