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1.
We present another interpretation of the data by P. Marko? and give numerous new illustrations of our conception. All the existing numerical data look perfectly compatible with predictions of the self-consistent theory of localization.  相似文献   

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Stable hydrogen and oxygen isotopes were analysed in water samples from the River Danube and its tributaries during a longitudinal survey performed in August 2005 on Serbian territory. Danube river water data ranged from?80‰ to?66‰ for δ2H, and from?11.2‰ to?9.3‰ for δ18O with δ values increasing downstream. The isotopic signatures of the adjacent tributaries (the Tisza, the Sava and the Velika Morava) sampled at the locations close to their confluence with the Danube (Titel, Ostru?nica and Ljubi?evski most, respectively) just about the time of the campaign were enriched (?67‰ and?63‰ for δ2H, and?9.3‰ and?8.9‰ for δ18O) with respect to the Danube water because of their catchment effects. Hydrogen and oxygen stable isotope values were used in combination with measured physico-chemical and biological parameters to trace hydrological and transport processes in these river systems. The mixing relationships between the Danube main stream and its tributaries were estimated using the mass balance for isotopic composition and electrical conductivity as conservative parameters. Evidence of an incomplete mixing process at the ?enta location, 8 km below the confluence of the Tisza river, with its participation of 88% was shown by its oxygen-18 content. The correlations between river water isotope composition and physico-chemical and biological parameters are discussed.  相似文献   

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李晓静 《中国物理 B》2010,19(3):30201-030201
A class of oscillator of the El Ni?o-Southern oscillation model is considered. Using Mawhin's continuation theorem, a result on the existence of periodic solutions for ENSO model is obtained.  相似文献   

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It is shown that the preliminary exposure of ZnO, triglycine sulfate, and potassium hydrogen phthalate crystals in ultralow crossed magnetic fields—Earth’s magnetic field and ac pump field—leads to a resonance change in their microhardness. The resonance frequency of microhardness peaks is determined by the classical condition of electron paramagnetic resonance only at certain orientations of the crystals with respect to the Earth’s magnetic field BEarth. Rotations of all samples with respect to the direction BEarth by angle θ reduce the resonance frequency in proportion to cosθ. The observed anisotropy has been attributed to the presence of their own local magnetic fields Bloc ? BEarth in the crystals.  相似文献   

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It has been shown that for the Reissner-Nordström solution to the vacuum Einstein field equations charge, like mass, has a unique space-time signature (Marsh, Found. Phys. 38:293–300, 2008). The presence of charge results in a negative curvature. This work, which includes a discussion of effective mass, is extended here to the Kerr-Newman solution.  相似文献   

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A strong influence of Ni content on the diffusion-controlled growth of the (Cu,Ni)3Sn and (Cu,Ni)6Sn5 phases by coupling different Cu(Ni) alloys with Sn in the solid state is reported. The continuous increase in the thickness ratio of (Cu,Ni)6Sn5 to (Cu,Ni)3Sn with the Ni content is explained by combined kinetic and thermodynamic arguments as follows: (i) The integrated interdiffusion coefficient does not change for the (Cu,Ni)3Sn phase up to 2.5 at.% Ni and decreases drastically for 5 at.% Ni. On the other hand, there is a continuous increase in the integrated interdiffusion coefficient for (Cu,Ni)6Sn5 as a function of increasing Ni content. (ii) With the increase in Ni content, driving forces for the diffusion of components increase for both components in both phases but at different rates. However, the magnitude of these changes alone is not large enough to explain the high difference in the observed growth rate of the product phases because of Ni addition. (iv) Kirkendall marker experiments indicate that the Cu6Sn5 phase grows by diffusion of both Cu and Sn in the binary case. However, when Ni is added, the growth is by diffusion of Sn only. (v) Also, the observed grain refinement in the Cu6Sn5 phase with the addition of Ni suggests that the grain boundary diffusion of Sn may have an important role in the observed changes in the growth rate.  相似文献   

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Certainty in the spin wave stiffness D0 was achieved for the first time in the problem of invars under Fe-Ni alloy polarized neutron scattering. A temperature power dependence of stiffness D = D0ΤX, with x ?0.5, was obtained for the entire ferromagnetic region Τ = 1 — T/Tc, from Τ = 0.1to Τ = 0.9. The spin stiffness was found to be D0 = 137 meVÅ2. Possible causes of scaling dependence CD(T) are discussed.  相似文献   

10.
The effect of gallium alloying on the structure, the phase composition, and the properties of quasibinary Ni50Mn50–zGaz (0 ? z ? 25 at %) alloys is studied over a wide temperature range. The influence of the alloy composition on the type of crystal structure in high-temperature austenite and martensite and the critical martensitic transformation temperatures is analyzed. A general phase diagram of the magnetic and structural transformations in the alloys is plotted. The temperature–concentration boundaries of the B2 and L21 superstructures in the austenite field, the tetragonal L10 (2M) martensite, and the 10M and 14M martensite phases with complex multilayer crystal lattices are found. The predominant morphology of martensite is shown to be determined by the hierarchy of the packets of thin coherent lamellae of nano- and submicrocrystalline crystals with planar habit plane boundaries close to {011}B2. Martensite crystals are twinned along one of the 24 \(24\left\{ {011} \right\}{\left\langle {01\bar 1} \right\rangle _{B2}}\) “soft” twinning shear systems, which provides coherent accommodation of the martensitic transformation–induced elastic stresses.  相似文献   

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Abstract

The role of Ni addition in Cu on the growth of intermetallic compounds in the Cu–Sn system is studied based on microstructure, crystal structure and quantitative diffusion analysis. The diffraction pattern analysis of intermetallic compounds indicates that the presence of Ni does not change their crystal structure. However, it strongly affects the microstructural evolution and diffusion rates of components. The growth rate of (Cu,Ni)3Sn decreases without changing the diffusion coefficient because of the increase in growth rate of (Cu,Ni)6Sn5. For 3 at.% or higher Ni addition in Cu, only the (Cu,Ni)6Sn5 phase grows in the interdiffusion zone. The elongated grains of (Cu,Ni)6Sn5 are found when it is grown from (Cu,Ni)3Sn. This indicates that the newly formed intermetallic compound joins with the existing grains of the phase. On the other hand, smaller grains are found when this phase grows directly from Cu in the absence of (Cu,Ni)3Sn indicating the ease of repeated nucleation. Grain size of (Cu,Ni)6Sn5 decreases with further increase in Ni content, which indicates a further reduction of activation barrier for nucleation. The relations for the estimation of relevant diffusion parameters are established considering the diffusion mechanism in the Cu(Ni)–Sn system, which is otherwise impossible in the phases with narrow homogeneity range in a ternary system. The flux of Sn increases, whereas the flux of Cu decreases drastically with the addition of very small amount of Ni, such as 0.5 at.% Ni, in Cu. Analysis of the atomic mechanism of diffusion indicates the contribution from both lattice and grain boundary for the growth of (Cu,Ni)6Sn5 phase.  相似文献   

13.
《Physica A》1995,215(3):331-338
The Fourier analysis has been applied to observational sea surface temperature (SST) data from the Southern Pacific. The spectral response of the daily temperature fluctuations indicates that the so-called El Niño Southern Oscillation (ENSO) belongs to the class of dynamical phenomena which are in a self-organized critical state. This has implications on the predictability of the significant events in the ocean-atmosphere interaction process. A toy model is used to point out the similarities of this system with other large scale phenomena, as earthquakes and volcanic eruptions, which are considered to be consistent with the hypothesis of self-organized criticality. The qualitative agreement between observational data and results of numerical simulations demonstrates the validity extent of the theoretical approach.  相似文献   

14.
We show that photoproduction experiments provide propitious conditions to study the exotic state 1–+ in the and channels. For unpolarized photons contributions from natural and unnatural parity exchanges do not interfere with each other, a fact which permits to estimate the correctness of phase shift analyses. In photoproduction of the + system in the mass range ofa 2(1320) a more stringent limit on the product (1–+)Br(1–+) can be obtained than in experiments on Primakoff production on nuclei. Particularly favourable is the study of the state 1–+ in the coherent photoproduction of the 0 and 0 systems on nuclei, with significantly enlarged statistics and a simplified phase shift analysis.  相似文献   

15.
We report a continuous transition from outwardly rotating spiral waves to antispirals in the complex GinzburgLandau equation. Numerical simulations demonstrate that the normal spiral to antispiral transition is fulfilled through a rest spiral wave with zero propagation speed. The propagation direction of spiral waves and the power law behaviour close to the transition boundary are examined.  相似文献   

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Physics of the Solid State - The earlier developed methodology of ultrasonic investigation for determining the parameters of the Jahn–Teller effect (JTE) in impurity centers in crystals is...  相似文献   

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