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排序方式: 共有10000条查询结果,搜索用时 515 毫秒
991.
E. S. Moskalenko M. Larsson K. F. Karlsson P. O. Holtz B. Monemar W. V. Schoenfeld P. M. Petroff 《Physics of the Solid State》2007,49(10):1995-1998
We report on low-temperature microphotoluminescence (μ-PL) measurements of InAs/GaAs quantum dots (QDs) exposed to a lateral
external electric field. It is demonstrated that the QDs’ PL signal could be increased severalfold by altering the external
and/or the internal electric field, which could be changed by an additional infrared laser. A model which accounts for a substantially
faster lateral transport of the photoexcited carriers achieved in an external electric field is employed to explain the observed
effects. The results obtained suggest that the lateral electric fields play a major role for the dot luminescence intensity
measured in our experiment—a finding which could be used to tailor the properties of QD-based optoelectronic applications.
The text was submitted by the authors in English. 相似文献
992.
A. Speranza 《Russian Journal of Mathematical Physics》2007,14(2):238-242
A mathematical theory for estimating the mobility of localized unstable atmospheric disturbances evolving into vortices is
discussed. 相似文献
993.
N. B. Voznesensky E. V. Gavrilov A. P. Zhevlakov V. K. Kirillovskiĭ P. V. Orlov 《Technical Physics》2007,52(2):271-275
Methods and schemes to inspect the EUV mirror shape are developed on the basis of a point diffraction interferometer with computer processing of interferograms. A measurement accuracy to within 0.001 of a wavelength in the visual range is achieved. 相似文献
994.
A. D. Krisch 《The European Physical Journal A - Hadrons and Nuclei》2007,31(4):417-423
There will be a review of the history of polarized proton beams, and a discussion of the unexpected and still unexplained
large transverse spin effects found in several high-energy proton-proton spin experiments at the ZGS, AGS and Fermilab. Next,
there will be a discussion of present and possible future experiments on the violent elastic collisions of polarized protons
at IHEP-Protvino's 70GeV U-70 accelerator in Russia and the new high-intensity 50GeV J-PARC facility being built at Tokai
in Japan. 相似文献
995.
The major achievements of the G. F. Gauze Scientific-Research Institute of New Antibiotics, Russian Academy of Medical Sciences, over the last 50 years are reviewed. The structures of antibiotics and related compounds discovered at the Institute and important for medical practise and/or of theoretical interest as new compounds with high biological activity are described.Dedicated to the memory of Director of the G. F. Gauze Scientific-Research Institute of New Antibiotics, Russian Academy of Medical Sciences, and Corresponding Member of the Russian Academy of Medical Sciences Prof. Yu. V. Dudnik (1938–2003).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1603–1618, November, 2004. 相似文献
996.
P. Danchev 《Lithuanian Mathematical Journal》2007,47(2):129-134
We prove the following theorem: Any abelian p-group is an n-Σ-group which is a strong ω-elongation of a totally projective group by a p
ω+n
-projective group precisely when it is totally projective. In particular, each p-torsion p
ω+n
-projective n-Σ-group is a direct sum of countable p-groups of length not exceeding ω + n and vice versa. These two claims generalize our recent results in [6] and [7].
Published in Lietuvos Matematikos Rinkinys, Vol. 47, No. 2, pp. 155–162, April–June, 2007. 相似文献
997.
Motivated by the central limit problem for convex bodies, we study normal approximation of linear functionals of high-dimensional
random vectors with various types of symmetries. In particular, we obtain results for distributions which are coordinatewise
symmetric, uniform in a regular simplex, or spherically symmetric. Our proofs are based on Stein’s method of exchangeable
pairs; as far as we know, this approach has not previously been used in convex geometry. The spherically symmetric case is
treated by a variation of Stein’s method which is adapted for continuous symmetries.
This work was done while at Stanford University. 相似文献
998.
999.
Alexander G. Ramm Alexandra B. Smirnova Angelo Favini 《Annali di Matematica Pura ed Applicata》2003,182(1):37-52
A nonlinear operator equation F(x)=0, F:H→H, in a Hilbert space is considered. Continuous Newton’s-type procedures based on a construction of a dynamical system with
the trajectory starting at some initial point x
0 and becoming asymptotically close to a solution of F(x)=0 as t→+∞ are discussed. Well-posed and ill-posed problems are investigated.
Received: June 29, 2001; in final form: February 26, 2002?Published online: February 20, 2003
This paper was finished when AGR was visiting Institute for Theoretical Physics, University of Giessen. The author thanks
DAAD for support 相似文献
1000.