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91.
Siberian Mathematical Journal - We address the unital right alternative bimodules over the matrix algebras $ {\mathrm{M}}_{n}(\Phi) $ of order $ n\geq 3 $ , prove that each of these... 相似文献
92.
Motohiko Hikuma Haruo Obana Takeo Yasuda Isao Karube Shuichi Suzuki 《Analytica chimica acta》1980,116(1):61-67
The sensor consists of immobilized E. coli (which contains glutamate decarboxylase) and a carbon dioxide gas-sensor. Continuous introduction of sample solution into a flow system incorporating the sensor gives a potential which increases until a steady state is reached after 5 min. Measurements can also be made with only a 1- or 3-min introduction period with little loss of sensitivity. Calibration plots of mV measurements vs. logarithmic glutamic acid concentration are linear in the range 100–800 mg l-1. The sensor is highly selective, stable and reproducible. It has been applied to the determination of glutamic acid in fermentation broths. 相似文献
93.
We study symmetric hyperbolic systems with memory-type dissipation and investigate their dissipative structures. We treat two cases: memory-type diffusion and memory-type relaxation, and observe that the dissipative structures of these two cases are essentially different. Namely, we show that the dissipative structure of the system with memory-type diffusion is of the standard type, while that of the system with memory-type relaxation is of the regularity-loss type. 相似文献
94.
The number of limit cycles for three dimensional Lotka–Volterra systems is an open problem. Recently, Yu et al. (2016) constructed some examples with the possibility of the existence of four limit cycles. Unfortunately, multiple limit cycles are not visible by numerical simulations, because all of them are very close to the interior equilibrium and extremely small. We present a concrete example with multiple limit cycles for three dimensional Lotka–Volterra systems which we can confirm them by numerical simulations. First we prepare the modified formula to compute coefficients of the normal form for the generalized Hopf bifurcation. Applying this formula to three dimensional Lotka–Volterra competitive systems with the aid of the computer algebra system, we derive the critical parameter values explicitly such that the interior equilibrium is exactly an unstable weak focus. Also we show that the heteroclinic cycle on the boundary of is repelling. This implies that there exists a stable limit cycle by the Poincare–Bendixson theorem. Then, adding some suitable perturbations to parameters, we generate additional two limit cycles near the interior equilibrium by the generalized Hopf bifurcation. Finally we confirm that there exist three limit cycles by numerical simulations. 相似文献
95.
Hideaki Matsunaga a & Satoru Murakami 《Journal of Difference Equations and Applications》2013,19(7):661-689
For nonlinear autonomous functional difference equations, the existence of the local stable manifolds, together with the local unstable manifolds and the local center-unstable manifolds, is shown. As an application, the principle of linearization which states that stabilities and instabilities for the zero solution of nonlinear equations can be derived from those of the zero solution of the linearized equations under some circumstances is established for functional difference equations. 相似文献
96.
Effects of a finite ion temperature on the Hall magnetohydrodynamics (MHD), which breaks down for a finite ion temperature, are clarified in terms of a rigorous three-field kinetic dispersion relation. The MHD mode equation becomes anisotropic with respect to the ion pressure because of the double adiabaticity in ion dynamics. 相似文献
97.
Anisotropic optical absorption properties of single-walled carbon nanotubes (SWNTs) are determined from a vertically aligned SWNT film for 0.5-6 eV. Absorption peaks at 4.5 and 5.25 eV are found to exhibit remarkable polarization dependence and have relevance to optical properties of graphite. A method for determining a nematic order parameter for an aligned SWNT film based on the collinear absorption peak at 4.5 eV is presented, followed by the determination of the optical absorption cross section. 相似文献
98.
Ohwada K Fujii Y Katsuki Y Muraoka J Nakao H Murakami Y Sawa H Ninomiya E Isobe M Ueda Y 《Physical review letters》2005,94(10):106401
The present resonant x-ray scattering has been performed on a monoclinically split single domain of NaV(2)O(5). The observation of a critically enhanced contrast between V(4+) and V(5+) ions has led us to the unequivocal conclusion of the charge-order pattern of the low-temperature phase of NaV(2)O(5) below T(c) = 35 K. In spite of the possible four types of configuration of the zigzag-type charge-order patterns in the ab plane (A,A',B and B'), the stacking sequence along the c axis is determined as the AAA'A' type by comparison with model calculations. 相似文献
99.
Some of the physical and thermodynamic properties of III–V liquids can be explained by assuming that the liquids have a dual structure. The thermodynamic model which has been established for the present paper is a partially associated solution model. It was constructed on the assumption of the existence of associated complexes. The asymmetry of the liquidus curve and the amount of excess free energy determined from the phase diagram analysis can be explained by using the model. Some of the thermodynamic parameters obtained in this study are found to have important physical meanings. The interaction parameter between monoatomic species, ωA,B is in a good agreement with the theoretical value proposed by Stringfellow. The heat of formation of associated complexes can be represented explicitly in terms of the spectroscopic ionicity and the dehybridization factor. The free energy of formation is empirically evaluated to be 20-6(fi ?0.17)RT?35,000fiDcal/mol for III–V binary liquids. 相似文献
100.
Hiroaki Nitani Masato Yuya Takahiro Ono Takashi Nakagawa Satoshi Seino Kenji Okitsu Yoshiteru Mizukoshi Shuichi Emura Takao A. Yamamoto 《Journal of nanoparticle research》2006,8(6):951-958
A sample of Au–Pd bimetallic nanoparticles supported on γ-Fe2O3 was synthesized in a sonochemically one-pot process. The structural analyses of the synthesized sample were performed by the techniques of X-ray Absorption Fine Structure (XAFS), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and UV–vis spectrometry. Results indicated that the synthesized sample formed a core-shell structure in which a gold core was surrounded by a thin palladium shell. The reaction rate constant for the hydrogenation of cyclohexene of the present sample showed higher value than that of Pd nanoparticles supported on γ-Fe2O3 and core-shell structured Au–Pd nanoparticles supported on SiO2. The present sample is a promising catalyst material which has a high catalytic activity. 相似文献