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31.
Pavel P. Fedorov Alexander A. Alexandrov Valery V. Voronov Mariya N. Mayakova Alexander E. Baranchikov Vladimir K. Ivanov 《Journal of the American Ceramic Society》2021,104(6):2836-2848
Phase formation in the SrF2–LaF3 system was studied at temperatures ranging from 300°C to 450°C using nitrate flux. The solubility of LaF3 in SrF2 decreases with decreasing temperature. The equilibrium width of the solid solution region Sr1−xLaxF2+x at 400°C, it is 44.6 ± 0.4 mol% LaF3 (x = 0.446), at 350°C — 38.3 ± 0.7 mol% LaF3 (x = 0.383), and decreases almost to zero at 300°C. 相似文献
32.
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34.
Jimmy Lin G. Craig Murray Bonnie J. Dorr Jan Hajič Pavel Pecina 《Language Resources and Evaluation》2009,43(1):27-40
Thesauri and controlled vocabularies facilitate access to digital collections by explicitly representing the underlying principles
of organization. Translation of such resources into multiple languages is an important component for providing multilingual
access. However, the specificity of vocabulary terms in most thesauri precludes fully-automatic translation using general-domain
lexical resources. In this paper, we present an efficient process for leveraging human translations to construct domain-specific
lexical resources. This process is illustrated on a thesaurus of 56,000 concepts used to catalog a large archive of oral histories.
We elicited human translations on a small subset of concepts, induced a probabilistic phrase dictionary from these translations,
and used the resulting resource to automatically translate the rest of the thesaurus. Two separate evaluations demonstrate
the acceptability of the automatic translations and the cost-effectiveness of our approach.
相似文献
Jimmy LinEmail: |
35.
K. Levin Y. Zha R. J. Radtke Q. Si M. R. Norman H. -B. Schüttler 《Journal of Superconductivity》1994,7(3):563-570
We review the spin dynamics of the normal state of the cuprates with special emphasis on neutron data in both the YBa2Cu3O7– and La2–x
Sr
x
CuO4 systems. When realistic models of the Fermi surface shapes are incorporated, along with a moderate degree of spin fluctuations, we find good semiquantitative agreement with experiment for both cuprates. Building on the success of this Fermi-liquid-based scheme, we explore the implications ford-wave pairing from a number of vantage points. We conclude that our present experimental and theoretical understanding is inadequate to confirm or refute thed-wave scenario. 相似文献
36.
Gregory N. Gol''tsman Ivan G. Goghidze Pavel B. Kouminov Boris S. Karasik Alexei D. Semenov Evgeni M. Gershenzon 《Journal of Superconductivity》1994,7(4):751-755
The transient voltage response in both epitaxial and granular YBaCuO thin films to 80 ps pulses of YAGNd laser radiation of wavelength 0.63 and 1.54 m was studied. In the normal and resistive states both types of films demonstrate two components: a nonequilibrium picosecond component and a bolometric nanosecond one. The normalized amplitudes are almost the same for all films. In the superconducting state we observed a kinetic inductive response and two-component shape after integration. The normalized amplitude of the response in granular films is up to five orders of magnitude larger than in epitaxial films. We interpret the nonequilibrium response in terms of a suppression of the order parameter by the excess of quasiparticles followed by the change of resistance in the normal and resistive states or kinetic inductance in the superconducting state. The sharp rise of inductive response in granular films is explained both by a diminishing of the cross section for current percolation through the disordered network of Josephson weak links and by a decrease of condensate density in neighboring regions. 相似文献
37.
Marichev A. E. Levin R. V. Gordeeva A. B. Gagis G. S. Kuchinskii V. I. Pushnyi B. V. Prasolov N. D. Shmidt N. M. 《Technical Physics Letters》2017,43(1):88-91
Technical Physics Letters - Specific features of mechanical-stress relaxation in InGaAsP/InP heterostructures for 1064 nm laser radiation converters have been studied. It is established that stress... 相似文献
38.
Technical Physics Letters - Stabilization of a detonation wave in a stoichiometric hydrogen–air mixture flowing at a supersonic velocity into a plane symmetric channel with constriction has... 相似文献
39.
V. A. Levin N. E. Afonina V. G. Gromov I. S. Manuilovich V. V. Markov G. D. Smekhov A. N. Khmelevskii 《High Temperature》2016,54(6):837-841
On the basis of the Navier–Stokes equations, a parametric study of the influence of various factors on the development of initial perturbations caused by starting an air-blown annular nozzle is performed for the laminar model of flow. Flow regimes are found in which the start perturbations accompanying the initiation of the nozzle do not attenuate but pass to a quasi-periodic mode. The frequency Fourier spectrum of pressure fluctuations at the center of the thrust wall and the value of the thrust of the nozzle are determined. Typical pulsed pressure signals obtained in the calculation model and detected in the experiments are presented. 相似文献
40.
I. E. Strelnikova E. E. Grinberg Yu. I. Levin A. E. Amelina V. I. Rakhlin 《Inorganic Materials》2016,52(12):1250-1253
We have studied reactions of metallic magnesium with ethyl cellosolve and a mixture of ethyl cellosolve and tetraethyl orthosilicate and demonstrated the possibility of preparing a mixed magnesium–silicon cellosolvate that can be used as a precursor for the synthesis of forsterite and enstatite. 相似文献