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841.
V. V. Soshenko O. R. Rubinas V. V. Vorobyov S. V. Bolshedvorskii P. V. Kapitanova V. N. Sorokin A. V. Akimov 《Bulletin of the Lebedev Physics Institute》2018,45(8):237-240
A microwave antenna configuration shaped as coaxial resonant coils is proposed for exciting magnetic dipole transitions of the optical ground state of the nitrogen—vacancy color center in diamond. The field within the antenna is simulated, field amplitudes are experimentally measured. 相似文献
842.
A matrix continued fraction is defined and used for the approximation of a function
known as a power series in 1/zwith matrix coefficientsp×q, or equivalently by a matrix of functions holomorphic at infinity. It is a generalization of P-fractions, and the sequence of convergents converges to the given function. These convergents have as denominators a matrix, the columns of which are orthogonal with respect to the linear matrix functional associated to
. The case where the algorithm breaks off is characterized in terms of
. 相似文献
843.
介绍了以铽(Tb)激活的高密度发光玻璃和光导纤维发光玻璃的特性。它应用在X射线实时成像系统中,可大大改善空间分辨能力。用它做的转换屏比一般晶粒状荧光物质做的厚得多,特别适合用于高能X射线实时成像系统 相似文献
844.
George A. Domrachev Larisa G. Klapshina Vladimir V. Semenov William E. Douglas Oleg L. Antipov Alexander S. Kuzhelev Alexey A. Sorokin 《应用有机金属化学》2001,15(1):51-55
Novel bis(arene)metal‐containing polyacrylonitrile materials have been prepared by the polycyanoethylation reaction between acrylonitrile and (arene)2M (M = Cr or V; arene = PhH, C6H4Et2 or mesitylene) in the absence of solvent. The resulting star‐shaped molecules consist of a central (arene)2M species with up to four polyacrylonitrile arms covalently bonded to the arene ligands. The materials are readily soluble and films can be cast from solutions in acetonitrile. The IR and solid state 13C NMR spectra (or EPR spectrum for the oxidized chromium‐containing polymer) are consistent with the presence of a metal–arene bond and confirm the persistence of the sandwich structure. The properties of the thermolysed materials are consistent with the formation of conjugated naphthyridine‐type structures. The value of |n2| determined by the degenerate four‐wave mixing technique at 1064 nm with a 6 ns pulse duration for a solution in conc. H2SO4 (1 g l−1) of the chromium‐containing polymer pyrolysed at 350 °C was found to be 0.8 × 10−13 cm2 W−1 corresponding to |lRe χ(3)| = 0.4 × 10−11 esu. 相似文献
845.
The fluorine-ion conductivity of single crystals with a tysonite (LaF3) structure with heterovalent isomorphic substitutions of highly polarizable Cd2+ cations with a 18-electron shell for rare earth ions Ce3+ have been studied for the first time. Ce0.995Cd0.005F2.995 single crystals have been grown from melt by the Bridgman technique in a fluorinating atmosphere. The fluorine-ion conductivity of single crystal is measured by impedance spectroscopy in the temperature range from 153 to 1073 K, where it increases by a factor of 109, approaching the value σdc = 5 × 10–2 S/cm at 1073 K. At T0 = 450 ± 20 K, the dependence σdc(T) is split into two portions with the ion-transport activation enthalpy ΔHσ = 0.39 ± 0.01 eV (T < T0) and ΔHσ = 0.23 ± 0.02 eV (T > T0). It is found that at T = 293 K the conductivity σdc = 3 × 10–5 S/cm of Ce0.995Cd0.005F2.995 crystal is higher by a factor of 10 than the conductivity of the tysonite matrix CeF3 and close to the σdc value for Ce0.995Sr0.005F2.995 crystal. This finding indicates a significant effect of the substitutions of Cd2+ ions for Ce3+ on the σdc value and the advantage of Cd2+ ions over Ca2+ and Ba2+ from the viewpoint of increasing σdc. 相似文献
846.
Acoustical Physics - Abstract—Articulatory event detectors, i.e., detectors of transitions from one articulatory state to another, are formed on based on analysis of spectral–temporal... 相似文献
847.
A. P. Dodokin A. M. Kevorkov D. D. Perlov A. A. Sorokin 《Crystal Research and Technology》1991,26(6):803-808
Crystals of solid solutions (RxY1-x)3Al5O12 (where R is rare earth ion Er3+, Yb3+, Tb3+, Ho3+, Tm3+) with garnet structure were grown. The temperature dependencies of magnetic susceptibility for these crystals were obtained. On the basis of measurement of magnetic susceptibility a non-destructive technique for determining the concentration of rare earth ions in yttrium-aluminum garnets was developed. 相似文献