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101.
102.
D. K. Kuznetsov I. S. Baturin V. Ya. Shur N. Menou C. Muller T. Schneller A. Sternberg 《Physics of the Solid State》2006,48(6):1174-1176
The effect of irradiation with electrons and neutrons and of exposure to synchrotron radiation on cyclic switching of polarization in thin films of lead zirconate titanate Pb(Zr,Ti)O3 (PZT) was studied. It is shown that variations in the shape of switching currents are due to the generation of a spatially nonuniform bound internal field with account for an increase in the rate of bulk screening caused by irradiation. A correlation between structural variations and the evolution of the switching current measured during and after irradiation is established. 相似文献
103.
Alexey Yurasov Alexander Granovsky Sergey Tarapov Jean-Pierre Clerc 《Journal of magnetism and magnetic materials》2006
The transmission of millimeter-range electromagnetic waves (30–50 GHz) through a magnetic nanocomposite thin film exhibiting tunnel magnetoresistance (TMR) is calculated. The relative change of transmission coefficient in an applied magnetic field due to the magnetorefractive effect is approximately linear with TMR and strongly depends on nanocomposite resistivity and film thickness. The obtained results are in a good agreement with experiment. 相似文献
104.
Tiago Buckup Timo Lebold Alexander Weigel Wendel Wohlleben Marcus Motzkus 《Journal of photochemistry and photobiology. A, Chemistry》2006,180(3):314-321
Biomolecules very often present complex energy deactivation networks with overlapping electronic absorption bands, making their study a difficult task. This can be especially true in transient absorption spectroscopy when signals from bleach, excited state absorption and stimulated emission contribute to the signal. However, quantum control spectroscopy can be used to discriminate specific electronic states of interest by applying specifically designed laser pulses. Recently, we have shown the control of energy flow in bacterial light-harvesting using shaped pump pulses in the visible and the selective population of pathways in carotenoids using an additional depletion pulse in the transient absorption technique. Here, we apply a closed-loop optimization approach to β-carotene using a spatial light modulator to decipher the energy flow network after a multiphoton excitation with a shaped ultrashort pulse in the near-IR. After excitation, two overlapping bands were detected and identified as the S1 state and the first triplet state T1. Using the transient absorption signal at a specific probe delay as feedback, the triplet signal could be optimized over the singlet contribution. 相似文献
105.
Alexander Kolokolov Nikolay Kosarev 《Journal of Mathematical Modelling and Algorithms》2006,5(2):189-199
In this paper the algorithms for solving the p-median problem based on the Benders decomposition are investigated. A family of problems hard for solving with such algorithms is constructed and then generalized to a special NP-hard case of the p-median problem. It is shown that the effectiveness of the considered algorithms depends on the choice of the optimal values of the dual variables used in Benders cuts. In particular, the depth of the cuts can be equal to one. 相似文献
106.
R. G. Makitra G. G. Midyana E. Ya. Pal’chikova 《Russian Journal of Applied Chemistry》2006,79(1):43-49
The influence of physicochemical properties of organic solvents on the distribution constants of aromatic carboxylic acids between the organic and aqueous phases was examined. 相似文献
107.
108.
Alexander Samsonow 《Colloid and polymer science》1911,8(2):96-97
Ohne Zusammenfassung 相似文献
109.
V. B. Philippov N. Ya. Kirpichnikova A. S. Kirpichnikova 《Journal of Mathematical Sciences》2003,117(2):4028-4033
The problem on the diffraction of the electromagnetic plane wave on a small obstacle included in a layer is investigated. The obstacle is assumed to be an elliptic cylinder whose diameter and focal distance are small in comparison with the length of the incident wave. It is proved that the small obstacle radiates as a point source, and its amplitude is proportional to the area of the cross-section and the jumps of the dielectric and magnetic constants on the interfaces. Bibliography: 5 titles. 相似文献
110.
G.N Hile Alexander Stanoyevitch 《Journal of Mathematical Analysis and Applications》2004,295(2):595-610
We generalize the heat polynomials for the heat equation to more general partial differential equations, of higher order with respect to both the time variable and the space variables. Whereas the heat equation requires only one family of polynomials, for an equation of the ?th order with respect to time we introduce ? families of polynomials. These families correspond to the ? initial conditions specified by the Cauchy problem. 相似文献