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81.
Yoshikatsu Miyashita Tohru Okuyama Kazutomo Yamaura Kiyokatsu Jinno Shin-Ichi Sasaki 《Analytica chimica acta》1987
The carcinogenicities of polynuclear aromatic hydrocarbons in particulates extracted from diesel engine exhaust are predicted on the basis of the combined bay-L region theory proposed earlier, in conjunction with pattern recognition techniques. The predicted carcinogenicities agree well with experimental data, thus showing the validity of the proposed model equations. 相似文献
82.
83.
We study the relation between the spectral gap above the ground state and the decay of the correlations in the ground state in quantum spin and fermion systems with short-range interactions on a wide class of lattices. We prove that, if two observables anticommute with each other at large distance, then the nonvanishing spectral gap implies exponential decay of the corresponding correlation. When two observables commute with each other at large distance, the connected correlation function decays exponentially under the gap assumption. If the observables behave as a vector under the U(1) rotation of a global symmetry of the system, we use previous results on the large distance decay of the correlation function to show the stronger statement that the correlation function itself, rather than just the connected correlation function, decays exponentially under the gap assumption on a lattice with a certain self-similarity in (fractal) dimensions D < 2. In particular, if the system is translationally invariant in one of the spatial directions, then this self-similarity condition is automatically satisfied. We also treat systems with long-range, power-law decaying interactions. 相似文献
84.
A generalized phase-shift method is developed for automatic measurement of principal-stress directions in the whole field of a model from photoelastic experiments. This method uses a set of light intensities obtained from the rotation of polaroids in dark-field plane polariscopes at each point. To investigate the accuracy of the measurement, time-series light intensity curves with different noise and different numbers of data which constitute the curves are used in computer simulation. The error of the measurement of the principal-stress directions obtained by the method is not greatly affected by noise when the number of data exceeds 50. This method is applied to a circular disk subjected to a concentrated load. The principal-stress directions obtained by the method are found to be in good agreement with the theory.Presented at 1996 International Workshop on Interferometry (IWI ‘96), August 27–29, Saitama, Japan. 相似文献
85.
Reika Fukuizumi Tohru Ozawa 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2005,16(3):1000-1011
Exponential decay estimates are obtained for complex-valued solutions to nonlinear elliptic equations in
\mathbbRn ,\mathbb{R}^{n} ,
where the linear term is given by Schr?dinger operators H = − Δ + V with nonnegative potentials V and the nonlinear term is given by a single power with subcritical Sobolev exponent in the attractive case. We describe specific
rates of decay in terms of V, some of which are shown to be optimal. Moreover, our estimates provide a unified understanding of two distinct cases in
the available literature, namely, the vanishing potential case V = 0 and the harmonic potential case V(x) = |x|2. 相似文献
86.
Tohru Kanno Jun-ichi Horiuchi Masayoshi Kobayashi 《Reaction Kinetics and Catalysis Letters》2000,70(1):81-89
Lithium made a Mn-Mg-O solid solution stable upon exposure of methane, decreased the ethane and ethylene formation rates, and increased the COx formation rate during the oxidative coupling of methane. On the other hand, on MgO, lithium inhibited COx formation markedly and enhanced the selectivity of ethane 47% to 76%. 相似文献
87.
Tohru Morimoto 《Differential Geometry and its Applications》2008,26(1):75-78
For each subriemannian manifold of constant subriemannian symbol we construct a Cartan connection canonically associated with this structure. 相似文献
88.
89.
2-Mercaptobenzothiazole (MBT) loaded on glass beads with the aid of collodion was prepared and used for selective preconcentration of μg l?1 levels of copper(II) and lead from aqueous solutions. Copper and lead were quantitatively retained on the loaded beads from solutions of pH 5.0–6.0 and >5.0, respectively, while cadmium(II) and zinc(II) were retained at ? pH 6.0 and 7.0, respectively. The retention capacity of the loaded beads was ca. 108 μg Cu g?1 (1.7 μmol g?1) at pH 5.5 for beads of 0.3–0.4 mm diameter. The mole ratios of MBT to copper(II) and lead(II) were ca. 10 and 45, respectively, regardless of the amount of MBT loaded on the beads. Copper was completely retained on the column at a high flow rate (21.7 ml min? cm?2) and lead(II) at up to 12.7 ml min? cm?2. Cadmium(II) and zinc(II) were not retained quantitatively even at low flow rates (< 1.2 ml min?1 cm?2). Thus, selective preconcentration of copper and lead was achieved by passing the sample through the column at high flow rate at pH 6.5. The copper and lead retained on the column were complete eluted together with the collodion with 5 ml of MIBK by batch-mode elution, and determined directly by one-drop atomic absorption spectrometry. Copper(II) and lead(II) in several kinds of water were determined. 相似文献
90.
Tohru Niida Yasuo Kousaka Shinji Oda 《Particle & Particle Systems Characterization》1988,5(3):139-143
The method described is based on the fact that the measurement of particles in the gaseous phase is generally easier than that in the liquid phase for fine particles smaller than 1 μm in diameter. The system consists of a liquid nebulizing unit, evaporator, condenser, mixing diluter and two different aerosol sizing instruments. It has been found that this method can continuously detect particulate impurities in ultrapure water in situ and can measure the size distribution of fine powders in the submicron particle size range down to about 0.05 μm. 相似文献