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31.
The domain structure of a thin single-crystal plate of the iron garnet Tb3Fe5O12 has been investigated using the magneto-optical method in the temperature range near the magnetic compensation point of this ferrimagnet T c = 248.6 K. It has been shown that, when the temperature of the sample approaches the magnetic compensation point, the domain width significantly increases, but remains finite at T = T c . The magnetic H-T phase diagram, which determines the boundary between the multidomain and domain-free (uniformly magnetized) states of the sample, has been constructed using the data on visual observations of the transformation of the domain structure with variations in the temperature and external magnetic field. The results obtained have been interpreted in terms of the thermodynamic theory of stability of different magnetic phases of a two-sublattice cubic ferrimagnet near T c . 相似文献
32.
Two ferrocene derivatives containing palladacycles with bidentate (C,N) and tridentate (C,N,N) ligands were successfully used as catalysts for the hydroarylation of norbornene. 相似文献
33.
V. V. Ammosov E. N. Ardashev D. S. Baranov V. I. Hleborad A. A. Ivanilov P. V. Ivanov V. I. Konyushko V. M. Korablev V. A. Korotkov V. V. Makeev A. G. Myagkov N. A. Netyaga A. Yu. Polyarush A. A. Sokolov E. P. Kuznetsov H. -J. Grabosch H. H. Kaufmann U. Krecker R. Nahnhauer S. Nowak S. Schlenstedt H. Vogt SKAT-Collaboration 《Zeitschrift fur Physik C Particles and Fields》1986,30(2):183-189
For charged current neutrino nucleus interactions at energies below 30 GeV, resulting from an experiment with the freon filled bubble chamber SKAT,K 0 and Λ production is investigated. An estimation of the total strange and charm production cross section is made.K 0 and Λ production rates are given in dependence on different inclusive variables. The production properties forK 0′s and Λ′s are discussed in terms of the Quark-Parton-Model. Comparisons with other ν-experiments at higher energies are performed. 相似文献
34.
I. I. Antakov E. V. Zasypkin E. V. Sokolov 《International Journal of Infrared and Millimeter Waves》1993,14(5):1001-1015
Formulas for shifts of gyrotron autooscillation frequency due to change of electron beam parameters are presented. The frequency shifts can be commensurable with the frequency band of the beam-unloaded cavity. The autooscillation frequency is most sensitive to the change of the magnetic field, less to the change of the anode voltage and least to the the change of the beam voltage. Experiments presented are in satisfactory agreement with the theory.The authors wish to thank M.I. Petelin for his interest to the present work. 相似文献
35.
We propose a source of multimode squeezed light that can be used for superresolving microscopy. This source is an optical parametric amplifier with a properly chosen diaphragm on its output and a Fourier lens. We demonstrate that such an arrangement produces squeezed prolate spheroidal waves that are the eigenmodes of the optical imaging scheme used in microscopy and discuss the conditions of the degree of squeezing and of the number of spatial modes in illuminating light. 相似文献
36.
Wang Y Rafailovich M Sokolov J Gersappe D Araki T Zou Y Kilcoyne AD Ade H Marom G Lustiger A 《Physical review letters》2006,96(2):028303
Strong dependence of the crystal orientation, morphology, and melting temperature (Tm) on the substrate is observed in the semicrystalline polyethylene thin films. The Tm decreases with the film thickness decrease when the film is thinner than a certain critical thickness, and the magnitude of the depression increases with increasing surface interaction. We attribute the large Tm depression to the decrease in the overall free energy on melting, which is caused by the substrate attraction force to the chains that competes against the interchain force which drives the chains to crystallization. 相似文献
37.
38.
N. Naumova T. Schlegel V. T. Tikhonchuk C. Labaune I. V. Sokolov G. Mourou 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,55(2):393-398
Short laser pulses at super-high intensities such as those proposed in the Extreme Light Infrastructure (ELI) project
open new prospects for efficient acceleration of ions in overdense plasmas. A simple analytical model and numerical simulations
demonstrate that pulses with intensities exceeding 1022 W/cm2 may efficiently accelerate ions to high energies up to a few GeV.
Maximum ion energy and the energy spectrum of the accelerated ions can be tuned by an appropriate choice of laser pulse intensity
and duration at a given plasma density distribution. 相似文献
39.
S. F. Dubinin V. I. Sokolov V. D. Parkhomenko V. I. Maksimov N. B. Gruzdev 《Physics of the Solid State》2009,51(10):2019-2022
The fine structure of a hexagonal zinc oxide crystal doped with nickel ions of the composition Zn1 − x
Ni
x
O has been studied using neutron diffraction and magnetic measurements. It is established that even at very low doping levels
(x = 0.0004), the crystal undergoes local distortions in basal planes of the initial hexagonal lattice. The local distortions
are assumed to be sources of the formation of ferromagnetism in compounds of this class. 相似文献
40.
Koga T Seo YS Zhang Y Shin K Kusano K Nishikawa K Rafailovich MH Sokolov JC Chu B Peiffer D Occhiogrosso R Satija SK 《Physical review letters》2002,89(12):125506
We report an anomalous swelling of polymer thin films in carbon dioxide (CO(2)) which is associated (in both locus and form) with the density fluctuation ridge that forms along the extension of the coexistence curve of gas and liquid in the P-T phase diagram. Neutron reflectivity results showed that CO(2) could be sorbed to a large extent ( approximately 60%) in thin polymer films even when the bulk miscibility of the polymer with CO(2) is very poor. The anomalous swelling is found to scale with the polymer radius of gyration (R(g)) and extends to a distance approximately 10 R(g). 相似文献