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991.
G. E. Malashkevich V. N. Sigaev G. I. Semkova B. Champagnon 《Physics of the Solid State》2004,46(3):552-556
The spectral-luminescent properties of silica gel glasses coactivated by Ce4+ and Eu3+ ions are investigated. The structure of the glasses is studied using x-ray powder diffraction and small-angle neutron scattering. The inference is drawn that Ce4+-Eu3+ centers with high-symmetry Eu(III) oxo complexes, which are formed in the glasses, have nanocrystalline nature. These centers are characterized by a weak vibronic interaction of Eu3+ ions with the matrix. The size of nanocrystallites formed under the synthesis conditions and at coactivator concentrations used is approximately equal to 10 nm. 相似文献
992.
M. E. Kompan V. P. Kuznetsov V. V. Rozanov A. V. Yakubovich 《Physics of the Solid State》2004,46(6):1110-1112
The size of an ionistor capacitor structure is found to change during its charging and discharging. The specific feature of this effect that distinguishes it from other known effects of changing sizes under electric and magnetic fields (the piezoelectric effect and striction) is the complete hysteresis; i.e., the size reached under the exposure remains unchanged after the field is turned off. 相似文献
993.
The crystallization of nickel nanoclusters is investigated using a molecular dynamics simulation with tight-binding potentials. The formation of a cluster structure depends on the cooling conditions. Slow cooling results in the formation of a face-centered cubic structure, whereas fast cooling, according to the data obtained in 40% of the simulation experiments, leads to the formation of an icosahedral structure. The molecular dynamics simulation experiments demonstrate the possibility of controlling the formation of a structure of nickel nanoclusters during crystallization. 相似文献
994.
P. A. Vityaz 《Physics of the Solid State》2004,46(4):606-610
Technological features of the commercial production of detonation-synthesis nanodiamonds at the SINTA Joint-Stock Company and the characteristics of the nanodiamonds and diamond-containing mixtures produced are considered. Nanodiamond applications in the production of composite electrolytic coatings that are based on chromium, nickel, gold, and silver, exhibit good service properties, and save on the use of noble metals and electric power are exemplified. Nanodiamond applications for the modification of plastics, antifriction lubricants, and oxide coatings grown by microarc oxidation of aluminum alloys are also considered. The prospective application of nanodiamonds as a raw material in the synthesis of diamond powders and superhard composites by static and shock-wave loading is demonstrated. 相似文献
995.
Experimental data for two-and three-component compositions (dyes embedded in gelatinous and polymeric matrices) that are Weigert-sensitive
to polarized radiation in a wide spectral range are reported. It is shown that the matrix considerably affects the photoanisotropic
properties of the compositions. 相似文献
996.
The ion transverse velocity distribution functions and the fraction η of ions heated above a certain energy W
1 are calculated as applied to the ion cyclotron resonance heating method of isotope separation. It is assumed that the longitudinal
ion velocity distribution in a plasma source is nonequilibrium. Under high heating temperatures, the averaged ion transverse
velocity distribution becomes essentially nonequilibrium and exhibits two maxima. The ion heating efficiency η is calculated
for W
1=40 eV and various values of the parameter p=λ/L, where λ is the wavelength of the electric field of an antenna and L is the heating zone extension. The relative contributions of the time-of-flight and Doppler broadenings are evaluated. 相似文献
997.
The cross section of absorption of electromagnetic radiation by a fine spherical conducting particle is estimated in terms
of the classical kinetic theory of electrical conduction. The mixed diffuse-specular mechanism of charge carrier reflection
from the sample boundary is considered. A correlation between the coefficient of specular reflection and the absorption cross
section at different temperatures is analyzed. 相似文献
998.
The electrodynamic properties of the interface between two periodic dielectric superlattices are studied. It is shown that
the interface may serve as a guide for an electromagnetic wave whose field decays exponentially on both sides of the plane
of the interface. The field and power flux distributions, as well as the frequency dependence of the field penetration depth,
are studied. 相似文献
999.
The feasibility of an effective high-luminance light source based on an open discharge is considered. Experimental data for
the light characteristics of different cathodoluminescent screens are presented. Phosphor coatings are excited by an electron
beam initiated by a planar cathode-grid injector in an inert gas atmosphere. The feasibility of maintaining an open discharge
using continuous or pulsed-periodic excitation of the gas medium in the light emitter is discussed. The use of the specular
method to excite the phosphor coating of the screen makes it possible to achieve a higher luminance and a higher luminous
efficacy in comparison with these characteristics for cathodophosphors. The design of the cathode-grid unit allows for a large
surface area of the electron injector, making it promising for wide-aperture light sources. 相似文献
1000.
A study is made of the possibility of controlling the spatial distribution of the degree of ionization in a modified Penning cell with a cathode divided into several sections that are at different potentials. It is shown that an almost uniform plasma can be produced when applying an optimal potential of the control electrode. This enables the generation of wide ion beams in this system. An ion extraction efficiency of several tens of percent is achieved, which is substantially higher than in conventional ion sources. 相似文献