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11.
A. I. Burkhanov P. V. Bondarenko S. I. Raevskaya A. V. Shil’nikov I. P. Raevskiĭ 《Physics of the Solid State》2006,48(6):1114-1116
The dielectric properties of a ceramic and a single crystal of the same composition 0.9NaNbO3-0.1Gd1/3NbO3 (NNG10) with different prehistories of the material are investigated in the low-and infralow-frequency ranges. It is revealed that the dielectric aging of the material based on the NaNbO3 antiferroelectric with a smeared phase transition differs in character from similar phenomena observed in relaxor ferroelectrics. 相似文献
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Characterization of spherical particles using high-order neural networks and scanning flow cytometry
Vladimir V. Berdnik Alexander Shvalov Valeri Maltsev Valery A. Loiko 《Journal of Quantitative Spectroscopy & Radiative Transfer》2006,102(1):62-72
We retrieve the radius R, real n and imaginary k parts of the refractive index of homogeneous spherical particles using angular distribution of the light-scattering intensity. To solve the inverse light-scattering problem we use a high-order neural-network technique. The effect of network parameters on optimization is examined. The technique is evaluated for noise-corrupted input data at 0.6 μm<R<10.6 μm, 1.02<n<1.38, and 0<k<0.03. The errors of retrieval for nonabsorbing particles do not exceed 0.05 μm for radius and 0.015 for refractive index. The experimental verification is fulfilled by experimental data retrieved by means of a scanning flow cytometer. The light-scattering profiles of polystyrene beads and spherized red blood cells are processed with the high-order neural networks and a non-linear regression at Mie theory. The parameters retrieved by the high-order neural networks correlate well with the parameters retrieved by the least-square method. 相似文献
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A two-fraction model that makes it possible to calculate analytically the complex dielectric permittivity of ice in the far infrared and submillimeter wavelength ranges is proposed. The librational and vibrational fractions are considered. The first fraction, consisting of rigid dipoles executing anharmonic reorientations in defects of the structure, gives rise to the librational band of ice at 800 cm?1. The second fraction consists of elastically vibrating oppositely charged H-bonded molecules. This fraction describes two bands of ice in the range 100–300 cm?1, and the nonresonant background of dielectric losses in the submillimeter wavelength range. The dielectric permittivity spectra of ice calculated for the temperature of ?7°C are consistent with the experimental spectra. The spectra of ice at the temperature ?30°C are predicted. 相似文献
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V. I. Burkov E. P. Peredereĭ E. V. Fedotov B. V. Mill’ Yu. V. Pisarevskiĭ 《Crystallography Reports》2008,53(5):843-846
The absorption and circular dichroism spectra of langasite family crystals are studied. Wide bands in the range of 285–500 nm that are related to the structure lattice defects are found. For all the crystals, these bands are in approximately the same spectral region, have identical structures, and can be attributed to one type of defects formed by cation vacancies and excess oxygen atoms in the optically active positions. 相似文献
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A. I. Olemskoĭ 《JETP Letters》2007,85(2):127-130
The complexity measure of the infinite set of self-similar hierarchically constrained ensembles is determined in the framework of the generalized combinatory approach. It is shown that, as the hierarchical coupling increases, the complexity increases to a value that decreases with increasing the dispersion of this coupling and with decreasing the branching degree of the hierarchical tree. 相似文献
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