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31.
Distributed computation can be described in terms of the fundamental operations of information storage, transfer, and modification. To describe the dynamics of information in computation, we need to quantify these operations on a local scale in space and time. In this paper we extend previous work regarding the local quantification of information storage and transfer, to explore how information modification can be quantified at each spatiotemporal point in a system. We introduce the separable information, a measure which locally identifies information modification events where separate inspection of the sources to a computation is misleading about its outcome. We apply this measure to cellular automata, where it is shown to be the first direct quantitative measure to provide evidence for the long-held conjecture that collisions between emergent particles therein are the dominant information modification events.  相似文献   
32.
The structural, resistive, magnetic, and magnetoresistive properties of the La0.6Sr0.3 ? x Bi x Mn1.1O3 ceramics have been studied. The substitution of Bi ions for Sr ions increases the lattice parameter of the rhombohedral perovskite structure, decreases the metal-semiconductor and ferromagnet-paramagnet phase transition temperatures and the peak of the magnetoresistive effect, and increases the resistivity, approaching the system to the ferroelectric state. The 55Mn NVR study indicates on the high-frequency Mn3+ ? Mn4+ superexchange and heterogeneity of the valence and magnetic states of manganese due to the nonuniformity of distribution of all ions and defects. The phase diagram has been constructed, which shows a strong correlation between the structural, magnetic, and magnetoresistive properties.  相似文献   
33.
Quartz glasses containing ultradisperse particles (with a mean radius of 5 ± 3 nm) of semiconductor compounds CuxS and CuInS2 were synthesized using the sol-gel technology. The line and differential absorption spectra of such glasses were investigated. In the range 600–700 nm, the samples demonstrate absorption bands that are assigned to the lowest-lying energy transition in quantum-size particles. Excitation by laser pulses with a wavelength of 540 nm causes the effect of induced absorption in the range of 500–950 nm. The induced absorption in the samples containing CuxS nanoparticles undergoes relaxation which has a characteristic time of ∼500 psec, and in the samples with CuInS2 nanoparticles it has a two-exponential form with τ1 ≈ 30 psec and τ2>1 nsec. Translated from Zhurnal Prikladnoi Spektroskopii, vol. 67, No. 4, pp. 507–511, July–August, 2000.  相似文献   
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35.
Russian Physics Journal - The method for deposition of high entropy alloy (HEA) films is discussed. It consists in the film deposition on a substrate in vacuum from multi-component gas-metal plasma...  相似文献   
36.
The structure, lattice imperfection, and properties of ceramic samples La0.6 ? x Nd x Sr0.3Mn1.1O3-δ (x = 0–0.4) have been investigated using the X-ray diffraction, resistive, magnetic (χac, 55Mn NMR), magnetoresistive and microscopic methods. It has been shown that there is a satisfactory agreement between the concentration decrease in the lattice parameters a of the rhombohedral (x = 0, 0.1, 0.2) and cubic (x = 0.3, 0.4) perovskite structures and the average ionic radii $\bar R$ for the lattice containing anion vacancies, cation vacancies, and nanostructured clusters with Mn2+ ions in A-positions. With an increase in the neodymium concentration x, the vacancy-type imperfection increases, the cluster-type imperfection decreases, the temperatures of metal-semiconductor phase transition T ms and ferromagnetic-paramagnetic phase transition T C decrease, and the content of the ferromagnetic phase decreases. The anomalous hysteresis is associated with the appearance of unidirectional exchange anisotropy induced in a clustered perovskite structure consisting of a ferromagnetic matrix and a planar antiferromagnetic cluster coherently coupled with it. An analysis of the asymmetrically broadened 55Mn NMR spectra has revealed a high-frequency electronic double exchange (Mn3+-O2?-Mn4+) ? (Mn4+-O2?-Mn3+) and an inhomogeneity of the magnetic and charge states of manganese due to the heterogeneous environment of the manganese ions by other ions and defects. The observed changes in the resonant frequency and width of the resonance curve are caused by changes in the ratio Mn3+/Mn4+ and magnetic inhomogeneity. An increase in the neodymium concentration x leads to a decrease in the ferromagnetic phase content determined from the dependences 4πNχac(T) and the 55Mn NMR curves. The phase diagram characterizes an interrelation between the composition, the imperfection of the structure, and the transport, magnetic, and magnetoresistive properties of lanthanum neodymium manganite perovskites. It has been found that there is a correlation between the imperfection, magnetic inhomogeneity, coercive force, and magnetoresistance effect exhibited by the perovskite structure.  相似文献   
37.
Oxidative chlorination of 2-aryl-5-benzylsulfanyl-1,3-oxazole-4-carbonitrile results in the previously unknown 4-cyano-1,3-oxazole-5-sulfonyl chlorides and N-substituted sulfonamides.  相似文献   
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39.
Photoactivation of the ozonolysis of adsorbed organic molecules is observed on the inactive surface of silica. The quantitative similarity between ozonolysis and photoozonolysis largely results from decomposition of the ozone during adsorption on SiO2 in the dark with the subsequent formation of secondary oxidizing agents, including OH radicals, and also from the effect of the type of adsorption on the reactivity.  相似文献   
40.
The eigenmodes of a hemispherical dielectric resonator placed on a perfectly conducting planar surface are studied. The resonator is shown to support independent E-and H-type oscillations. For E and H oscillations, the sums n + m of the polar and azimuthal indices are, respectively, even and odd. Accordingly, E and H oscillations exhibit, respectively, n-and (n + 1)-fold frequency degeneracy in azimuthal index m. The distributions of the whispering gallery mode fields on the surface of the hemisphere and on the external conducting plane are obtained. The energy distribution among the eigenmodes with polar index n=36 is studied. The polar angle that corresponds to the maximum of the whispering gallery mode field and the width of the energy localization region in terms of the polar angle are calculated. The number of field variations in the spherical coordinates are correlated with the indices of the resonator’s eigenmodes. The eigenfrequencies and Q factors of the resonator are plotted versus the permittivity of the isotropic environment in the 8-mm wavelength range.  相似文献   
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