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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
962.
Brandau C. Bartsch T. Böhm S. Böhme C. Hoffknecht A. Kieslich S. Knopp H. Schippers S. Shi W. Müller A. Grün N. Scheid W. Steih T. Bosch F. Franzke B. Kozhuharov C. Krämer A. Mokler P. H. Nolden F. Steck M. Stöhlker T. Stachura Z. 《Hyperfine Interactions》2003,146(1-4):41-45
Hyperfine Interactions - An overview of measurements of dielectronic recombination (DR) with the heaviest lithiumlike ions is presented. The experiments have been carried out at the heavy ion... 相似文献
963.
We develop a lattice-dynamical model based on the screw symmetry of single-walled carbon nanotubes that allows for reducing the size of the dynamical matrix to six, for all tube chiralities. The model uses force constants derived from fitting to the phonon dispersion of 2D graphite. We present the calculation procedure in a clear and transparent way, making the model easier to follow. We calculate the phonon dispersions of a number of nanotubes of different chiralities. The splitting of two highest Raman active modes and the radial breathing mode frequency are studied by changing the tube diameter and chirality. 相似文献
964.
Voronezh' Civil-Engineering Institute. Translated from Prikladnaya Mekhanika, Vol. 27, No. 1, pp. 89–95, January, 1991. 相似文献
965.
A. M. Samoilenko 《Ukrainian Mathematical Journal》2007,59(2):243-292
We present results of the investigation of the local behavior of smooth functions in neighborhoods of their regular and critical
points and prove theorems on the mean values of the functions considered similar to the Lagrange finite-increments theorem.
We also study the symmetry of the derivative of an analytic function in the neighborhood of its multiple zero, prove new statements
of the Weierstrass preparation theorem related to the critical point of a smooth function with finite smoothness, determine
a nongradient vector field of a function in the neighborhood of its critical point, and consider one critical case of stability
of an equilibrium position of a nonlinear system.
__________
Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 59, No. 2, pp. 231–267, February, 2007. 相似文献
966.
967.
968.
P.A. Postigo A.R. Alija L.J. Martínez M.L. Dotor D. Golmayo J. Snchez-Dehesa C. Seassal P. Viktorovitch M. Galli A. Politi M. Patrini L.C. Andreani 《Photonics and Nanostructures》2007,5(2-3):79-85
Two-dimensional photonic crystal lasers have been fabricated on III–V semiconductor slabs. Tuning of the spontaneous emission in micro and nanocavities has been achieved by accurate control of the slab thickness. Different structures, some of them of new application to photonic crystal lasers, have been fabricated like the Suzuki-phase or the coupled-cavity ring-like resonators. Laser emission has been obtained by pulsed optical pumping. Optical characterization of the lasing modes have been performed showing one or more laser peaks centred around 1.55 μm. Far field characterization of the emission pattern has been realized showing different patterns depending on the geometrical shape of the structures. These kinds of devices may be used as efficient nanolaser sources for optical communications or optical sensors. 相似文献
969.
970.
We analyse some identifiers which can univocally identify hyperbolic components and Misiurewicz points of one-dimensional quadratic maps. After seeing the equivalence among the different identifiers and how to go from one to another, we show which are the best for some specific tasks. Likewise, we present the analytic expressions, some of them shown for the first time in this paper, to calculate these identifiers. Some experimental considerations are taken into account. 相似文献