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971.
Intense multi- and single-line laser operation is reported from semiconductively preionised atomic fluorine lasers employing an optimised capacitor transfer excitation circuitry. The performance and spectral characteristics of these lasers are discussed and compared to the characteristics of previously described atomic fluorine lasers. The efficiency of one of these lasers described, at optimum conditions, is reaching a value as high as 0.14%. To the best of our knowledge, this is the highest efficiency reported up date, for an atomic fluorine laser. 相似文献
972.
973.
974.
975.
A. L. Ivanovskii 《Theoretical and Experimental Chemistry》2007,43(1):1-27
The present state of research on the production and modeling of nanostructures based on titanium carbide-a typical representative
of an extensive class of carbides of d-and f-metals-is reviewed. Methods for the synthesis of various Ti-C nanostructures
(molecular clusters, nanocrystallites, nanospheres, nanofibers, nanowires) are examined, and their morphology, atomic structure,
and known physicochemical characteristics are described. Theoretical models of the atomic structure and properties of new
types of nanostructures in the titanium-carbon system (endo-and exohedral titanofullerenes, “hybrid” structures based on carbon
nanotubes, the so-called peapods, nanocables, and a number of others) and the prospects for their application as components
of nanoceramics, hydrogen accumulators, materials for spintronics, etc. are discussed.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 1, pp. 1–23, January–February, 2007. 相似文献
976.
S. Simic 《Mathematical Notes》2007,81(5-6):681-685
If f is an entire function of arbitrary finite order and with nonnegative Taylor coefficients, then we prove that its restriction to the positive part of the real axis belongs to de Haan’s class Γ. We also show that f/f′ is a Beurling slowly varying function. 相似文献
977.
We study problems of interpolation of positive linear operators in couples of ordered Banach spaces. From this viewpoint, we study couples of noncommutative spaces L 1, L ∞ associated with weights and traces on von Neumann algebras. 相似文献
978.
We consider a shock-type wave solution of the modified quintic complex Ginzburg-Landau equation and make a numerical study
of its spatiotemporal stability. Discussions related to the behavior of this front wave are introduced and it is shown how
the velocities of the wave can be used to collect information concerning the pattern formation in the system.
Published in Neliniini Kolyvannya, Vol. 10, No. 2, pp. 270–276, April–June, 2007. 相似文献
979.
We show how methods for estimating the concentration function of the sum of independent random variables can be used to obtain estimates of the concentration function for the values of additive functions under suitable conditions. Previously obtained estimates of the concentration function are consequences of the estimate obtained in the present paper for functions from of the class under consideration. 相似文献
980.